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1.
Nature ; 592(7856): 732-736, 2021 04.
Article in English | MEDLINE | ID: mdl-33911271

ABSTRACT

Cratons are Earth's ancient continental land masses that remain stable for billions of years. The mantle roots of cratons are renowned as being long-lived, stable features of Earth's continents, but there is also evidence of their disruption in the recent1-6 and more distant7-9 past. Despite periods of lithospheric thinning during the Proterozoic and Phanerozoic eons, the lithosphere beneath many cratons seems to always 'heal', returning to a thickness of 150 to 200 kilometres10-12; similar lithospheric thicknesses are thought to have existed since Archaean times3,13-15. Although numerous studies have focused on the mechanism for lithospheric destruction2,5,13,16-19, the mechanisms that recratonize the lithosphere beneath cratons and thus sustain them are not well understood. Here we study kimberlite-borne mantle xenoliths and seismology across a transect of the cratonic lithosphere of Arctic Canada, which includes a region affected by the Mackenzie plume event 1.27 billion years ago20. We demonstrate the important role of plume upwelling in the destruction and recratonization of roughly 200-kilometre-thick cratonic lithospheric mantle in the northern portion of the Slave craton. Using numerical modelling, we show how new, buoyant melt residues produced by the Mackenzie plume event are captured in a region of thinned lithosphere between two thick cratonic blocks. Our results identify a process by which cratons heal and return to their original lithospheric thickness after substantial disruption of their roots. This process may be widespread in the history of cratons and may contribute to how cratonic mantle becomes a patchwork of mantle peridotites of different age and origin.

2.
J Neurosci ; 43(47): 7913-7928, 2023 11 22.
Article in English | MEDLINE | ID: mdl-37802657

ABSTRACT

Numerous rare variants that cause neurodevelopmental disorders (NDDs) occur within genes encoding synaptic proteins, including ionotropic glutamate receptors. However, in many cases, it remains unclear how damaging missense variants affect brain function. We determined the physiological consequences of an NDD causing missense mutation in the GRIK2 kainate receptor (KAR) gene, that results in a single amino acid change p.Ala657Thr in the GluK2 receptor subunit. We engineered this mutation in the mouse Grik2 gene, yielding a GluK2(A657T) mouse, and studied mice of both sexes to determine how hippocampal neuronal function is disrupted. Synaptic KAR currents in hippocampal CA3 pyramidal neurons from heterozygous A657T mice exhibited slow decay kinetics, consistent with incorporation of the mutant subunit into functional receptors. Unexpectedly, CA3 neurons demonstrated elevated action potential spiking because of downregulation of the small-conductance Ca2+ activated K+ channel (SK), which mediates the post-spike afterhyperpolarization. The reduction in SK activity resulted in increased CA3 dendritic excitability, increased EPSP-spike coupling, and lowered the threshold for the induction of LTP of the associational-commissural synapses in CA3 neurons. Pharmacological inhibition of SK channels in WT mice increased dendritic excitability and EPSP-spike coupling, mimicking the phenotype in A657T mice and suggesting a causative role for attenuated SK activity in aberrant excitability observed in the mutant mice. These findings demonstrate that a disease-associated missense mutation in GRIK2 leads to altered signaling through neuronal KARs, pleiotropic effects on neuronal and dendritic excitability, and implicate these processes in neuropathology in patients with genetic NDDs.SIGNIFICANCE STATEMENT Damaging mutations in genes encoding synaptic proteins have been identified in various neurodevelopmental disorders, but the functional consequences at the cellular and circuit level remain elusive. By generating a novel knock-in mutant mouse, this study examined the role of a pathogenic mutation in the GluK2 kainate receptor (KAR) subunit, a subclass of ionotropic glutamate receptors. Analyses of hippocampal CA3 pyramidal neurons determined elevated action potential firing because of an increase in dendritic excitability. Increased dendritic excitability was attributable to reduced activity of a Ca2+ activated K+ channel. These results indicate that a pathogenic KAR mutation results in dysregulation of dendritic K+ channels, which leads to an increase in synaptic integration and backpropagation of action potentials into distal dendrites.


Subject(s)
Mutation, Missense , Receptors, Kainic Acid , Male , Female , Humans , Mice , Animals , Receptors, Kainic Acid/genetics , Receptors, Kainic Acid/metabolism , Neurons/physiology , Hippocampus/physiology , Pyramidal Cells/physiology
3.
BMC Cancer ; 24(1): 171, 2024 Feb 03.
Article in English | MEDLINE | ID: mdl-38310262

ABSTRACT

BACKGROUND: Radiotherapy delivery regimens can vary between a single fraction (SF) and multiple fractions (MF) given daily for up to several weeks depending on the location of the cancer or metastases. With limited evidence comparing fractionation regimens for oligometastases, there is support to explore toxicity levels to nearby organs at risk as a primary outcome while using SF and MF stereotactic ablative radiotherapy (SABR) as well as explore differences in patient-reported quality of life and experience. METHODS: This study will randomize 598 patients in a 1:1 ratio between the standard arm (MF SABR) and the experimental arm (SF SABR). This trial is designed as two randomized controlled trials within one patient population for resource efficiency. The primary objective of the first randomization is to determine if SF SABR is non-inferior to MF SABR, with respect to healthcare provider (HCP)-reported grade 3-5 adverse events (AEs) that are related to SABR. Primary endpoint is toxicity while secondary endpoints include lesional control rate (LCR), and progression-free survival (PFS). The second randomization (BC Cancer sites only) will allocate participants to either complete quality of life (QoL) questionnaires only; or QoL questionnaires and a symptom-specific survey with symptom-guided HCP intervention. The primary objective of the second randomization is to determine if radiation-related symptom questionnaire-guided HCP intervention results in improved reported QoL as measured by the EuroQoL-5-dimensions-5levels (EQ-5D-5L) instrument. The primary endpoint is patient-reported QoL and secondary endpoints include: persistence/resolution of symptom reporting, QoL, intervention cost effectiveness, resource utilization, and overall survival. DISCUSSION: This study will compare SF and MF SABR in the treatment of oligometastases and oligoprogression to determine if there is non-inferior toxicity for SF SABR in selected participants with 1-5 oligometastatic lesions. This study will also compare patient-reported QoL between participants who receive radiation-related symptom-guided HCP intervention and those who complete questionnaires alone. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT05784428. Date of Registration: 23 March 2023.


Subject(s)
Neoplasms , Radiosurgery , Humans , Neoplasms/mortality , Neoplasms/pathology , Neoplasms/radiotherapy , Progression-Free Survival , Quality of Life , Radiosurgery/adverse effects , Radiosurgery/methods , Equivalence Trials as Topic
4.
Dis Aquat Organ ; 157: 95-106, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38546193

ABSTRACT

Parasitic sea lice (Copepoda: Caligidae) colonising marine salmonid (Salmoniformes: Salmonidae) aquaculture production facilities have been implicated as a possible pressure on wild salmon and sea trout populations. This investigation uses monitoring data from the mainland west coast and Western Isles of Scotland to estimate the association of the abundance of adult female Lepeophtheirus salmonis (Krøyer) colonising farmed Atlantic salmon Salmo salar L. with the occurrence of juvenile and mobile L. salmonis on wild sea trout, anadromous S. trutta L. The associations were evaluated using generalised linear mixed models incorporating farmed adult female salmon louse abundances which are temporally lagged relative to dependent wild trout values. The pattern of lags, which is consistent with time for L. salmonis development between egg and infective stage, was evaluated using model deviances. A significant positive association is identified between adult female L. salmonis abundance on farms and juvenile L. salmonis on wild trout. This association is consistent with a causal relationship in which increases in the number of L. salmonis copepodids originating from lice colonising farmed Atlantic salmon cause an increase of L. salmonis abundance on wild sea trout.


Subject(s)
Copepoda , Fish Diseases , Salmo salar , Animals , Female , Trout , Aquaculture , Scotland/epidemiology , Fish Diseases/epidemiology , Fish Diseases/parasitology
5.
J Fish Biol ; 2024 Apr 28.
Article in English | MEDLINE | ID: mdl-38679466

ABSTRACT

The migratory behavior of Atlantic salmon (Salmo salar) post-smolts in coastal waters is poorly understood. In this collaborative study, 1914 smolts, from 25 rivers, in four countries were tagged with acoustic transmitters during a single seasonal migration. In total, 1105 post-smolts entered the marine study areas and 438 (39.6%) were detected on a network of 414 marine acoustic receivers and an autonomous underwater vehicle. Migration pathways (defined as the shortest distance between two detections) of up to 575 km and over 100 days at sea were described for all 25 populations. Post-smolts from different rivers, as well as individuals from the same river, used different pathways in coastal waters. Although difficult to generalize to all rivers, at least during the year of this study, no tagged post-smolts from rivers draining into the Irish Sea were detected entering the areas of sea between the Hebrides and mainland Scotland, which is associated with a high density of finfish aquaculture. An important outcome of this study is that a high proportion of post-smolts crossed through multiple legislative jurisdictions and boundaries during their migration. This study provides the basis for spatially explicit assessment of the impact risk of coastal pressures on salmon during their first migration to sea.

6.
Healthc Manage Forum ; 37(2): 86-89, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37731265

ABSTRACT

Mass casualty events can cause patient surges within healthcare facilities. These surges can be limited to hours or continue for days or weeks. As emergency departments are the front doors to the healthcare system, it is critical that they are prepared to accept patient surges. Focusing plans on optimizing space, staff, and supplies is critical to a successful response. Boarded or non-emergent patients must be diverted, discharged, and decanted from the emergency department to expand resuscitation space. If inadequate, non-clinical space may be required for patient care. Staff call-in lists should be maintained, and in-house berthing for staff during prolonged responses may be necessary. Further, identifying the spectrum of care, from conventional to crisis, is necessary to thrive during a disaster response: staff must understand that business as usual will not be compatible with austere disaster response before levels of care begin to decline.


Subject(s)
Disaster Planning , Mass Casualty Incidents , Humans , Surge Capacity , Emergency Service, Hospital , Critical Care
7.
Br J Cancer ; 128(4): 576-585, 2023 02.
Article in English | MEDLINE | ID: mdl-36482188

ABSTRACT

BACKGROUND: The efficacy and safety of primary re-irradiation for MSCC are not known. Our aim was to establish the efficacy and safety of biologically effective dose-based re-irradiation. METHODS: Patients presenting with MSCC at a previously irradiated spine segment, and not proceeding with surgical decompression, were eligible. A 3 Gray per fraction experimental schedule (minimum 18 Gy/6 fractions, maximum 30 Gy/10 fractions) was used, delivering a maximum cumulative spinal dose of 100 Gy2 if the interval since the last radiotherapy was within 6 months, or 130 Gy2 if longer. The primary outcome was a change in mobility from week 1 to week 5 post-treatment, as assessed by the Tomita score. The RTOG SOMA score was used to screen for spinal toxicity, and an MRI performed to assess for radiation-induced myelopathy (RIM). RESULTS: Twenty-two patients were enroled, of whom eleven were evaluable for the primary outcome. Nine of eleven (81.8%) had stable or improved Tomita scores at 5 weeks. One of eight (12.5%) evaluable for late toxicity developed RIM. CONCLUSIONS: Re-irradiation is an efficacious treatment for MSCC. There is a risk of RIM with a cumulative dose of 120 Gy2. CLINICAL TRIAL REGISTRATION: Cancer Trials Ireland (ICORG 07-11); NCT00974168.


Subject(s)
Radiation Injuries , Re-Irradiation , Spinal Cord Compression , Spinal Cord Neoplasms , Humans , Spinal Cord Compression/radiotherapy , Dose Fractionation, Radiation , Spinal Cord Neoplasms/radiotherapy , Treatment Outcome , Radiotherapy Dosage
8.
J Surg Res ; 291: 17-24, 2023 11.
Article in English | MEDLINE | ID: mdl-37331188

ABSTRACT

INTRODUCTION: Crises like the COVID-19 pandemic create blood product shortages. Patients requiring transfusions are placed at risk and institutions may need to judiciously administer blood during massive blood transfusions protocols (MTP). The purpose of this study is to provide data-driven guidance for the modification of MTP when the blood supply is severely limited. METHODS: This is a retrospective cohort study of 47 Level I and II trauma centers (TC) within a single healthcare system whose patients received MTP from 2017 to 2019. All TC used a unifying MTP protocol for balanced blood product transfusions. The primary outcome was mortality as a function of volume of blood transfused and age. Hemoglobin thresholds and measures of futility were also estimated. Risk-adjusted analyses were performed using multivariable and hierarchical regression to account for confounders and hospital variation. RESULTS: Proposed MTP maximum volume thresholds for three age groupings are as follows: 60 units for ages 16-30 y, 48 units for ages 31-55 y, and 24 units for >55 y. The range of mortality under the transfusion threshold was 30%-36% but doubled to 67-77% when the threshold was exceeded. Hemoglobin concentration differences relative to survival were clinically nonsignificant. Prehospital measures of futility were prehospital cardiac arrest and nonreactive pupils. In hospital risk factors of futility were mid-line shift on brain CT and cardiopulmonary arrest. CONCLUSIONS: Establishing MTP threshold practices under blood shortage conditions, such as the COVID pandemic, could sustain blood availability by following relative thresholds for MTP use according to age groups and key risk factors.


Subject(s)
COVID-19 , Wounds and Injuries , Humans , Retrospective Studies , Pandemics , COVID-19/therapy , Blood Transfusion/methods , Clinical Protocols , Trauma Centers
9.
J Fish Biol ; 102(2): 537-541, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36448734

ABSTRACT

Future warming scenarios are predicted to result in an increased frequency of high, and potentially stressful, temperatures in aquatic ecosystems. Here we examined whether the performance of wild underyearling Atlantic salmon (Salmo salar) in Scottish streams stocked with identical egg densities was influenced by thermal stress. Biomass and density declined with degree hours exceeding 23°C, indicating apparent mortality or emigration as a possible result of exposure to high temperatures. These results strengthen the need for further action such as riparian tree planting to reduce stream summer temperatures.


Subject(s)
Salmo salar , Animals , Temperature , Rivers , Ecosystem , Seasons
10.
Lancet Oncol ; 23(10): 1308-1320, 2022 10.
Article in English | MEDLINE | ID: mdl-36113498

ABSTRACT

BACKGROUND: Localised prostate cancer is commonly treated with external beam radiotherapy and moderate hypofractionation is non-inferior to longer schedules. Stereotactic body radiotherapy (SBRT) allows shorter treatment courses without impacting acute toxicity. We report 2-year toxicity findings from PACE-B, a randomised trial of conventionally fractionated or moderately hypofractionated radiotherapy versus SBRT. METHODS: PACE is an open-label, multicohort, randomised, controlled, phase 3 trial conducted at 35 hospitals in the UK, Ireland, and Canada. In PACE-B, men aged 18 years and older with a WHO performance status 0-2 and low-risk or intermediate-risk histologically-confirmed prostate adenocarcinoma (Gleason 4 + 3 excluded) were randomly allocated (1:1) by computerised central randomisation with permuted blocks (size four and six), stratified by centre and risk group to control radiotherapy (CRT; 78 Gy in 39 fractions over 7·8 weeks or, following protocol amendment on March 24, 2016, 62 Gy in 20 fractions over 4 weeks) or SBRT (36·25 Gy in five fractions over 1-2 weeks). Androgen deprivation was not permitted. Co-primary outcomes for this toxicity analysis were Radiation Therapy Oncology Group (RTOG) grade 2 or worse gastrointestinal and genitourinary toxicity at 24 months after radiotherapy. Analysis was by treatment received and included all patients with at least one fraction of study treatment assessed for late toxicity. Recruitment is complete. Follow-up for oncological outcomes continues. The trial is registered with ClinicalTrials.gov, NCT01584258. FINDINGS: We enrolled and randomly assigned 874 men between Aug 7, 2012, and Jan 4, 2018 (441 to CRT and 433 to SBRT). In this analysis, 430 patients were analysed in the CRT group and 414 in the SBRT group; a total of 844 (97%) of 874 randomly assigned patients. At 24 months, RTOG grade 2 or worse genitourinary toxicity was seen in eight (2%) of 381 participants assigned to CRT and 13 (3%) of 384 participants assigned to SBRT (absolute difference 1·3% [95% CI -1·3 to 4·0]; p=0·39); RTOG grade 2 or worse gastrointestinal toxicity was seen in 11 (3%) of 382 participants in the CRT group versus six (2%) of 384 participants in the SBRT group (absolute difference -1·3% [95% CI -3·9 to 1·1]; p=0·32). No serious adverse events (defined as RTOG grade 4 or worse) or treatment-related deaths were reported within the analysis timeframe. INTERPRETATION: In the PACE-B trial, 2-year RTOG toxicity rates were similar for five fraction SBRT and conventional schedules of radiotherapy. Prostate SBRT was found to be safe and associated with low rates of side-effects. Biochemical outcomes are awaited. FUNDING: Accuray.


Subject(s)
Prostatic Neoplasms , Radiosurgery , Radiotherapy, Intensity-Modulated , Androgens , Humans , Male , Prostatic Neoplasms/pathology , Radiosurgery/adverse effects , Radiotherapy, Intensity-Modulated/adverse effects , Radiotherapy, Intensity-Modulated/methods , Treatment Outcome
11.
Lancet Oncol ; 23(2): 304-316, 2022 02.
Article in English | MEDLINE | ID: mdl-35051385

ABSTRACT

BACKGROUND: Randomised trials have investigated various androgen deprivation therapy (ADT) intensification strategies in men receiving radiotherapy for the treatment of prostate cancer. This individual patient data meta-analysis of relevant randomised trials aimed to quantify the benefit of these interventions in aggregate and in clinically relevant subgroups. METHODS: For this meta-analysis, we performed a systematic literature search in MEDLINE, Embase, trial registries, the Web of Science, Scopus, and conference proceedings to identify trials with results published in English between Jan 1, 1962, and Dec 30, 2020. Multicentre randomised trials were eligible if they evaluated the use or prolongation of ADT (or both) in men with localised prostate cancer receiving definitive radiotherapy, reported or collected distant metastasis and survival data, and used ADT for a protocol-defined finite duration. The Meta-Analysis of Randomized trials in Cancer of the Prostate (MARCAP) Consortium was accessed to obtain individual patient data from randomised trials. The primary outcome was metastasis-free survival. Hazard ratios (HRs) were obtained through stratified Cox models for ADT use (radiotherapy alone vs radiotherapy plus ADT), neoadjuvant ADT extension (ie, extension of total ADT duration in the neoadjuvant setting from 3-4 months to 6-9 months), and adjuvant ADT prolongation (ie, prolongation of total ADT duration in the adjuvant setting from 4-6 months to 18-36 months). Formal interaction tests between interventions and metastasis-free survival were done for prespecified subgroups defined by age, National Comprehensive Cancer Network (NCCN) risk group, and radiotherapy dose. This meta-analysis is registered with PROSPERO, CRD42021236855. FINDINGS: Our search returned 12 eligible trials that provided individual patient data (10 853 patients) with a median follow-up of 11·4 years (IQR 9·0-15·0). The addition of ADT to radiotherapy significantly improved metastasis-free survival (HR 0·83 [95% CI 0·77-0·89], p<0·0001), as did adjuvant ADT prolongation (0·84 [0·78-0·91], p<0·0001), but neoadjuvant ADT extension did not (0·95 [0·83-1·09], p=0·50). Treatment effects were similar irrespective of radiotherapy dose, patient age, or NCCN risk group. INTERPRETATION: Our findings provide the strongest level of evidence so far to the magnitude of the benefit of ADT treatment intensification with radiotherapy for men with localised prostate cancer. Adding ADT and prolonging the portion of ADT that follows radiotherapy is associated with improved metastasis-free survival in men, regardless of risk group, age, and radiotherapy dose delivered; however, the magnitude of the benefit could vary and shared decision making with patients is recommended. FUNDING: University Hospitals Seidman Cancer Center, Prostate Cancer Foundation, and the American Society for Radiation Oncology.


Subject(s)
Androgen Antagonists/therapeutic use , Prostatic Neoplasms/therapy , Age Factors , Aged , Aged, 80 and over , Humans , Male , Middle Aged , Prostatic Neoplasms/mortality , Prostatic Neoplasms/pathology , Radiotherapy Dosage , Time Factors
12.
Int J Mol Sci ; 22(19)2021 Sep 30.
Article in English | MEDLINE | ID: mdl-34638945

ABSTRACT

The quest for the discovery and validation of radiosensitivity biomarkers is ongoing and while conventional bioassays are well established as biomarkers, molecular advances have unveiled new emerging biomarkers. Herein, we present the validation of a new 4-gene signature panel of CDKN1, FDXR, SESN1 and PCNA previously reported to be radiation-responsive genes, using the conventional G2 chromosomal radiosensitivity assay. Radiation-induced G2 chromosomal radiosensitivity at 0.05 Gy and 0.5 Gy IR is presented for a healthy control (n = 45) and a prostate cancer (n = 14) donor cohort. For the prostate cancer cohort, data from two sampling time points (baseline and Androgen Deprivation Therapy (ADT)) is provided, and a significant difference (p > 0.001) between 0.05 Gy and 0.5 Gy was evident for all donor cohorts. Selected donor samples from each cohort also exposed to 0.05 Gy and 0.5 Gy IR were analysed for relative gene expression of the 4-gene signature. In the healthy donor cohort, there was a significant difference in gene expression between IR dose for CDKN1, FXDR and SESN1 but not PCNA and no significant difference found between all prostate cancer donors, unless they were classified as radiation-induced G2 chromosomal radiosensitive. Interestingly, ADT had an effect on radiation response for some donors highlighting intra-individual heterogeneity of prostate cancer donors.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p21/genetics , Heat-Shock Proteins/genetics , Mitochondrial Proteins/genetics , Oxidoreductases Acting on Sulfur Group Donors/genetics , Proliferating Cell Nuclear Antigen/genetics , Prostatic Neoplasms/genetics , Radiation Tolerance/genetics , Transcriptome , Adult , Aged , Aged, 80 and over , Androgen Antagonists/pharmacology , Androgen Antagonists/therapeutic use , Case-Control Studies , Chromosomes/radiation effects , Cohort Studies , Humans , Male , Middle Aged , Multiplex Polymerase Chain Reaction/methods , Prognosis , Prostatic Neoplasms/blood , Prostatic Neoplasms/drug therapy , Radiation Dosage , Radiation Tolerance/drug effects , Real-Time Polymerase Chain Reaction/methods , Young Adult
13.
Br J Cancer ; 122(9): 1315-1323, 2020 04.
Article in English | MEDLINE | ID: mdl-32157242

ABSTRACT

BACKGROUND: The optimal EBRT schedule for MSCC is undetermined. Our aim was to determine whether a single fraction (SF) was non-inferior to five daily fractions (5Fx), for functional motor outcome. METHODS: Patients not proceeding with surgical decompression in this multicentre non-inferiority, Phase 3 trial were randomised to 10 Gy/SF or 20 Gy/5Fx. A change in mobility from baseline to 5 weeks for each patient, was evaluated by a Modified Tomita score: 1 = 'Walk unaided', 2 = 'With walking aid' and 3 = 'Bed-bound'. The margin used to establish non-inferiority was a detrimental change of -0.4 in the mean difference between arms. RESULTS: One-hundred and twelve eligible patients were enrolled. Seventy-three patients aged 30-87 were evaluated for the primary analysis. The 95% CI for the difference in the mean change in mobility scores between arms was -0.12 to 0.6. Since -0.4 is not included in the interval, there is evidence that 10 Gy/SF is non-inferior to 20 Gy/5Fx. One grade 3 AE was reported in the 5Fx arm. Twelve (26%) patients in the 5Fx arm had a Grade 2-3 AE compared with six (11%) patients in the SF arm (p = 0.093). CONCLUSION: For mobility preservation, one 10-Gy fraction is non-inferior to 20 Gy in five fractions, in patients with MSCC not proceeding with surgical decompression. CLINICAL TRIAL REGISTRATION: Cancer Trials Ireland ICORG 05-03; NCT00968643; EU-20952.


Subject(s)
Dose Fractionation, Radiation , Spinal Cord Compression/radiotherapy , Spinal Cord Neoplasms/radiotherapy , Adult , Aged , Aged, 80 and over , Female , Humans , Ireland/epidemiology , Male , Middle Aged , Radiotherapy/adverse effects , Risk Factors , Spinal Cord Compression/pathology , Spinal Cord Neoplasms/pathology , Treatment Outcome
14.
Am Nat ; 195(4): 678-690, 2020 04.
Article in English | MEDLINE | ID: mdl-32216673

ABSTRACT

Life-history theory predicts that investment per offspring should correlate negatively with the quality of the environment that offspring are anticipated to encounter; parents may use their own experience as juveniles to predict this environment and may modulate offspring traits, such as growth capacity and initial size. We manipulated nutrient levels in the juvenile habitat of wild Atlantic salmon (Salmo salar) to investigate the hypothesis that the egg size that maximizes juvenile growth and survival depends on environmental quality. We also tested whether offspring traits were related to parental growth trajectory. Mothers that grew fast when young produced more offspring and smaller offspring than mothers that grew slowly to reach the same size. Despite their size disadvantage, offspring of faster-growing mothers grew faster than those of slower-growing mothers in all environments, counter to the expectation that they would be competitively disadvantaged. However, they had lower relative survival in environments where the density of older predatory/competitor fish was relatively high. These links between maternal (but not paternal) growth trajectory and offspring survival rate were independent of egg size, underscoring that mothers may be adjusting egg traits other than size to suit the environment their offspring are anticipated to face.


Subject(s)
Body Size , Ecosystem , Salmo salar/growth & development , Animals , Female , Male , Ovum/cytology , Phenotype , Predatory Behavior , Salmo salar/physiology
15.
Am Nat ; 196(2): 132-144, 2020 08.
Article in English | MEDLINE | ID: mdl-32673096

ABSTRACT

Ecological pressures such as competition can lead individuals within a population to partition resources or habitats, but the underlying intrinsic mechanisms that determine an individual's resource use are not well understood. Here we show that an individual's own energy demand and associated competitive ability influence its resource use, but only when food is more limiting. We tested whether intraspecific variation in metabolic rate leads to microhabitat partitioning among juvenile Atlantic salmon (Salmo salar) in natural streams subjected to manipulated nutrient levels and subsequent per capita food availability. We found that individual salmon from families with a higher baseline (standard) metabolic rate (which is associated with greater competitive ability) tended to occupy faster-flowing water, but only in streams with lower per capita food availability. Faster-flowing microhabitats yield more food, but high metabolic rate fish only benefited from faster growth in streams with high food levels, presumably because in low-food environments the cost of a high metabolism offsets the benefits of acquiring a productive microhabitat. The benefits of a given metabolic rate were thus context dependent. These results demonstrate that intraspecific variation in metabolic rate can interact with resource availability to determine the spatial structuring of wild populations.


Subject(s)
Basal Metabolism/physiology , Ecosystem , Salmon/metabolism , Animals , Behavior, Animal/physiology , Female , Invertebrates , Male , Rivers , Water Movements
16.
Clin Proteomics ; 17(1): 41, 2020 Nov 20.
Article in English | MEDLINE | ID: mdl-33292167

ABSTRACT

Following the introduction of routine Prostate Specific Antigen (PSA) screening in the early 1990's, Prostate Cancer (PCa) is often detected at an early stage. There are also a growing number of treatment options available and so the associated mortality rate is generally low. However, PCa is an extremely complex and heterogenous disease and many patients suffer disease recurrence following initial therapy. Disease recurrence commonly results in metastasis and metastatic PCa has an average survival rate of just 3-5 years. A significant problem in the clinical management of PCa is being able to differentiate between patients who will respond to standard therapies and those who may benefit from more aggressive intervention at an earlier stage. It is also acknowledged that for many men the disease is not life threatenting. Hence, there is a growing desire to identify patients who can be spared the significant side effects associated with PCa treatment until such time (if ever) their disease progresses to the point where treatment is required. To these important clinical needs, current biomarkers and clinical methods for patient stratification and personlised treatment are insufficient. This review provides a comprehensive overview of the complexities of PCa pathology and disease management. In this context it is possible to review current biomarkers and proteomic technologies that will support development of biomarker-driven decision tools to meet current important clinical needs. With such an in-depth understanding of disease pathology, the development of novel clinical biomarkers can proceed in an efficient and effective manner, such that they have a better chance of improving patient outcomes.

17.
J Am Acad Dermatol ; 83(3): 839-846, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32344071

ABSTRACT

BACKGROUND: An Investigator Global Assessment (IGA) is recommended by health agencies for drug registration in atopic dermatitis (AD). Current IGA scales lack standardization. OBJECTIVES: To develop an IGA scale, training module, and clinical certification examination for use in AD trials; establish content validity; and assess reliability. METHODS: Expert dermatologists participated in the development of the validated IGA for AD (vIGA-ADTM). Reliability (interrater and intrarater) was assessed by 2 web-based surveys. Clinical certification for investigators consisted of a training module and examination. RESULTS: Expert consensus was achieved around a 5-point IGA scale including morphologic descriptions, and content validity was established. Survey 1 showed strong interrater reliability (Kendall's coefficient of concordance W [Kendall's W], 0.809; intraclass correlation [ICC], 0.817) and excellent agreement (weighted kappa, 0.857). Survey 2, completed 5 months after training of dermatologists, showed improvements in scale reliability (Kendall's W, 0.819; ICC, 0.852; weighted kappa, 0.889). In this study, 627 investigators completed vIGA-AD training and certification. LIMITATIONS: Ratings were assessed on photographs. CONCLUSION: A validated IGA scale and training module were developed with the intent of harmonizing assessment of disease severity in AD trials. Strong reliability and excellent agreement between assessments were observed.


Subject(s)
Consensus , Dermatitis, Atopic/diagnosis , Outcome Assessment, Health Care/standards , Severity of Illness Index , Adult , Child , Consensus Development Conferences as Topic , Dermatitis, Atopic/therapy , Dermatologists/standards , Dermatologists/statistics & numerical data , Humans , Observer Variation , Photography , Reproducibility of Results , Skin/diagnostic imaging , Surveys and Questionnaires/statistics & numerical data , Telecommunications
18.
BMC Neurosci ; 20(1): 57, 2019 12 10.
Article in English | MEDLINE | ID: mdl-31823725

ABSTRACT

BACKGROUND: Mammalian Shc (Src homology and collagen) proteins comprise a family of four phosphotyrosine adaptor molecules which exhibit varied spatiotemporal expression and signaling functions. ShcD is the most recently discovered homologue and it is highly expressed in the developing central nervous system (CNS) and adult brain. Presently however, its localization within specific cell types of mature neural structures has yet to be characterized. RESULTS: In the current study, we examine the expression profile of ShcD in the adult rat CNS using immunohistochemistry, and compare with those of the neuronally enriched ShcB and ShcC proteins. ShcD shows relatively widespread distribution in the adult brain and spinal cord, with prominent levels of staining throughout the olfactory bulb, as well as in sub-structures of the cerebellum and hippocampus, including the subgranular zone. Co-localization studies confirm the expression of ShcD in mature neurons and progenitor cells. ShcD immunoreactivity is primarily localized to axons and somata, consistent with the function of ShcD as a cytoplasmic adaptor. Regional differences in expression are observed among neural Shc proteins, with ShcC predominating in the hippocampus, cerebellum, and some fiber tracts. Interestingly, ShcD is uniquely expressed in the olfactory nerve layer and in glomeruli of the main olfactory bulb. CONCLUSIONS: Together our findings suggest that ShcD may provide a distinct signaling contribution within the olfactory system, and that overlapping expression of ShcD with other Shc proteins may allow compensatory functions in the brain.


Subject(s)
Central Nervous System/metabolism , Shc Signaling Adaptor Proteins/metabolism , Animals , Central Nervous System/cytology , Immunohistochemistry , Male , Neural Stem Cells/cytology , Neural Stem Cells/metabolism , Neurons/cytology , Neurons/metabolism , Rats, Sprague-Dawley , Src Homology 2 Domain-Containing, Transforming Protein 2/metabolism , Src Homology 2 Domain-Containing, Transforming Protein 3/metabolism
19.
Ecol Lett ; 21(2): 287-295, 2018 02.
Article in English | MEDLINE | ID: mdl-29243313

ABSTRACT

Organisms can modify their surrounding environment, but whether these changes are large enough to feed back and alter their evolutionary trajectories is not well understood, particularly in wild populations. Here we show that nutrient pulses from decomposing Atlantic salmon (Salmo salar) parents alter selection pressures on their offspring with important consequences for their phenotypic and genetic diversity. We found a strong survival advantage to larger eggs and faster juvenile metabolic rates in streams lacking carcasses but not in streams containing this parental nutrient input. Differences in selection intensities led to significant phenotypic divergence in these two traits among stream types. Stronger selection in streams with low parental nutrient input also decreased the number of surviving families compared to streams with high parental nutrient levels. Observed effects of parent-derived nutrients on selection pressures provide experimental evidence for key components of eco-evolutionary feedbacks in wild populations.


Subject(s)
Biological Evolution , Nutrients , Salmon , Animals , Phenotype , Selection, Genetic
20.
Mol Ecol ; 27(3): 804-814, 2018 02.
Article in English | MEDLINE | ID: mdl-29274177

ABSTRACT

The importance of parental contributions to offspring development and subsequent performance is self-evident at a genomic level; however, parents can also affect offspring fitness by indirect genetic and environmental routes. The life history strategy that an individual adopts will be influenced by both genes and environment; and this may have important consequences for offspring. Recent research has linked telomere dynamics (i.e., telomere length and loss) in early life to future viability and longevity. Moreover, a number of studies have reported a heritable component to telomere length across a range of vertebrates, although the effects of other parental contribution pathways have been far less studied. Using wild Atlantic salmon with different parental life histories in an experimental split-brood in vitro fertilization mating design and rearing the resulting families under standardized conditions, we show that there can be significant links between parental life history and offspring telomere length (studied at the embryo and fry stage). Maternal life history traits, in particular egg size, were most strongly related to offspring telomere length at the embryonic stage, but then became weaker through development. In contrast, paternal life history traits, such as the father's growth rate in early life, had a greater association in the later stages of offspring development. However, offspring telomere length was not significantly related to either maternal or paternal age at reproduction, nor to paternal sperm telomere length. This study demonstrates both the complexity and the importance of parental factors that can influence telomere length in early life.


Subject(s)
Salmo salar/growth & development , Salmo salar/metabolism , Telomere Homeostasis , Telomere/metabolism , Animals , Embryo, Nonmammalian/metabolism , Fertilization , Linear Models , Male , Salmo salar/embryology , Spermatozoa/metabolism
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