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1.
Diabet Med ; : e15326, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890775

RESUMO

AIMS: The direct cost of diabetes to the UK health system was estimated at around £10 billion in 2012. This analysis updates that estimate using more recent and accurate data sources. METHODS: A pragmatic review of relevant data sources for UK nations was conducted, including population-level data sets and published literature, to generate estimates of costs separately for Type 1, Type 2 and gestational diabetes. A comprehensive cost framework, developed in collaboration with experts, was used to create a population-based cost of illness model. The key driver of the analysis was prevalence of diabetes and its complications. Estimates were made of the excess costs of diagnosis, treatment and diabetes-related complications compared with the general UK population. Estimates of the indirect costs of diabetes focused on productivity losses due to absenteeism and premature mortality. RESULTS: The direct costs of diabetes in 2021/22 for the UK were estimated at £10.7 billion, of which just over 40% related to diagnosis and treatment, with the rest relating to the excess costs of complications. Indirect costs were estimated at £3.3 billion. CONCLUSIONS: Diabetes remains a considerable cost burden in the UK, and the majority of those costs are still spent on potentially preventable complications. Although rates of some complications are reducing, prevalence continues to increase and effective approaches to primary and secondary prevention continue to be needed. Improvements in data capture, data quality and reporting, and further research on the human and financial implications of increasing incidence of Type 2 diabetes in younger people are recommended.

2.
AIDS Care ; 36(4): 432-441, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37011383

RESUMO

Although HIV incidence and mortality rates have declined over the past 20 years, HIV health disparities continue to persist among patients living in urban communities. Barriers to proficient health outcomes for persons with HIV (PWH) in urban communities include lack of access to care, resulting from limited transportation or clinic availability. While healthcare systems in rural communities provide telemedicine (TM) services to PWH to eliminate transportation and accessibility barriers, few examples exist regarding TM use for PWH in urban communities. This project's goal was to increase the provision of healthcare services in an urban setting to PWH, using TM. As guided by "Integration of Healthcare Delivery Service" theories and key principles, we created an integration framework comprised of several simultaneous, overlapping activities to include: (1) capacity building (2) clinical standardization (3) community and patient engagement and (4) evaluation performance and measurements. This paper describes major activities involved with developing, implementing and evaluating a TM program for PWH. We discuss results, challenges, and lessons learned from integrating this program into our existing healthcare system.


Assuntos
Infecções por HIV , Telemedicina , Humanos , Infecções por HIV/terapia , Atenção à Saúde , Instituições de Assistência Ambulatorial
3.
Mol Syst Biol ; 18(11): e10886, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36366891

RESUMO

During development, cell state transitions are coordinated through changes in the identity of molecular regulators in a cell type- and dose-specific manner. The ability to rationally engineer such transitions in human pluripotent stem cells (hPSC) will enable numerous applications in regenerative medicine. Herein, we report the generation of synthetic gene circuits that can detect a desired cell state using AND-like logic integration of endogenous miRNAs (classifiers) and, upon detection, produce fine-tuned levels of output proteins using an miRNA-mediated output fine-tuning technology (miSFITs). Specifically, we created an "hPSC ON" circuit using a model-guided miRNA selection and circuit optimization approach. The circuit demonstrates robust PSC-specific detection and graded output protein production. Next, we used an empirical approach to create an "hPSC-Off" circuit. This circuit was applied to regulate the secretion of endogenous BMP4 in a state-specific and fine-tuned manner to control the composition of differentiating hPSCs. Our work provides a platform for customized cell state-specific control of desired physiological factors in hPSC, laying the foundation for programming cell compositions in hPSC-derived tissues and beyond.


Assuntos
MicroRNAs , Células-Tronco Pluripotentes , Humanos , Genes Sintéticos , Diferenciação Celular/genética , Células-Tronco Pluripotentes/metabolismo , Redes Reguladoras de Genes , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas/metabolismo
4.
Neuropathol Appl Neurobiol ; 49(4): e12925, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37465879

RESUMO

AIMS: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with complex aetiology. Despite evidence of neuromuscular junction (NMJ) denervation and 'dying-back' pathology in models of SOD1-dependent ALS, evidence in other genetic forms of ALS is limited by a lack of suitable animal models. TDP-43, a key mediator protein in ALS, is overexpressed in neurons in Thy1-hTDP-43WT mice. We therefore aimed to comprehensively analyse NMJ pathology in this model of ALS. METHODS: Expression of TDP-43 was assessed via western blotting. Immunohistochemistry techniques, alongside NMJ-morph quantification, were used to analyse motor neuron number, NMJ denervation status and terminal Schwann cell morphology. RESULTS: We present a time course of progressive, region-specific motor neuron pathology in Thy1-hTDP-43WT mice. Thy1-driven hTDP-43 expression increased steadily, correlating with developing hindlimb motor weakness and associated motor neuron loss in the spinal cord with a median survival of 21 days. Pronounced NMJ denervation was observed in hindlimb muscles, mild denervation in cranial muscles but no evidence of denervation in either forelimb or trunk muscles. NMJ pathology was restricted to motor nerve terminals, with denervation following the same time course as motor neuron loss. Terminal Schwann cells were lost from NMJs in hindlimb muscles, directly correlating with denervation status. CONCLUSIONS: Thy1-hTDP-43WT mice represent a severe model of ALS, with NMJ pathology/denervation of distal muscles and motor neuron loss, as observed in ALS patients. This model therefore provides an ideal platform to investigate mechanisms of dying-back pathology, as well as NMJ-targeting disease-modifying therapies in ALS.


Assuntos
Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Camundongos , Animais , Esclerose Lateral Amiotrófica/patologia , Doenças Neurodegenerativas/patologia , Junção Neuromuscular/patologia , Neurônios Motores/patologia , Células de Schwann/metabolismo , Células de Schwann/patologia , Denervação , Proteínas de Ligação a DNA/metabolismo , Camundongos Transgênicos , Modelos Animais de Doenças
5.
J Cell Physiol ; 237(11): 4303-4316, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36166694

RESUMO

Vascular calcification is associated with aging, type 2 diabetes, and atherosclerosis, and increases the risk of cardiovascular morbidity and mortality. It is an active, highly regulated process that resembles physiological bone formation. It has previously been established that pharmacological doses of metformin alleviate arterial calcification through adenosine monophosphate-activated protein kinase (AMPK)-activated autophagy, however the specific pathway remains elusive. In the present study we hypothesized that metformin protects against arterial calcification through the direct autophagic degradation of runt-related transcription factor 2 (Runx2). Calcification was blunted in vascular smooth muscle cells (VSMCs) by metformin in a dose-dependent manner (0.5-1.5 mM) compared to control cells (p < 0.01). VSMCs cultured under high-phosphate (Pi) conditions in the presence of metformin (1 mM) showed a significant increase in LC3 puncta following bafilomycin-A1 (Baf-A; 5 nM) treatment compared to control cells (p < 0.001). Furthermore, reduced expression of Runx2 was observed in the nuclei of metformin-treated calcifying VSMCs (p < 0.0001). Evaluation of the functional role of autophagy through Atg3 knockdown in VSMCs showed aggravated Pi-induced calcification (p < 0.0001), failure to induce autophagy (punctate LC3) (p < 0.001) and increased nuclear Runx2 expression (p < 0.0001) in VSMCs cultured under high Pi conditions in the presence of metformin (1 mM). Mechanistic studies employing three-way coimmunoprecipitation with Runx2, p62, and LC3 revealed that p62 binds to both LC3 and Runx2 upon metformin treatment in VSMCs. Furthermore, immunoblotting with LC3 revealed that Runx2 specifically binds with p62 and LC3-II in metformin-treated calcified VSMCs. Lastly, we investigated the importance of the autophagy pathway in vascular calcification in a clinical setting. Ex vivo clinical analyses of calcified diabetic lower limb artery tissues highlighted a negative association between Runx2 and LC3 in the vascular calcification process. These studies suggest that exploitation of metformin and its analogues may represent a novel therapeutic strategy for clinical intervention through the induction of AMPK/Autophagy Related 3 (Atg3)-dependent autophagy and the subsequent p62-mediated autophagic degradation of Runx2.


Assuntos
Metformina , Calcificação Vascular , Humanos , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Metformina/efeitos adversos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Transdução de Sinais , Calcificação Vascular/tratamento farmacológico , Calcificação Vascular/prevenção & controle
6.
Hum Mol Genet ; 29(16): 2647-2661, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32686835

RESUMO

Amyotrophic lateral sclerosis (ALS) is an incurable neurological disease with progressive loss of motor neuron (MN) function in the brain and spinal cord. Mutations in TARDBP, encoding the RNA-binding protein TDP-43, are one cause of ALS, and TDP-43 mislocalization in MNs is a key pathological feature of >95% of ALS cases. While numerous studies support altered RNA regulation by TDP-43 as a major cause of disease, specific changes within MNs that trigger disease onset remain unclear. Here, we combined translating ribosome affinity purification (TRAP) with RNA sequencing to identify molecular changes in spinal MNs of TDP-43-driven ALS at motor symptom onset. By comparing the MN translatome of hTDP-43A315T mice to littermate controls and to mice expressing wild type hTDP-43, we identified hundreds of mRNAs that were selectively up- or downregulated in MNs. We validated the deregulated candidates Tex26, Syngr4, and Plekhb1 mRNAs in an independent TRAP experiment. Moreover, by quantitative immunostaining of spinal cord MNs, we found corresponding protein level changes for SYNGR4 and PLEKHB1. We also observed these changes in spinal MNs of an independent ALS mouse model caused by a different patient mutant allele of TDP-43, suggesting that they are general features of TDP-43-driven ALS. Thus, we identified SYNGR4 and PLEKHB1 to be deregulated in MNs at motor symptom onset in TDP-43-driven ALS models. This spatial and temporal pattern suggests that these proteins could be functionally important for driving the transition to the symptomatic phase of the disease.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteínas de Ligação a DNA/genética , Proteínas de Membrana/genética , Sinaptogirinas/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Transgênicos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Biossíntese de Proteínas/genética , RNA-Seq , Medula Espinal/metabolismo , Medula Espinal/patologia
7.
J Anat ; 241(5): 1120-1132, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36056593

RESUMO

The aetiology and pathophysiology of many diseases of the motor unit remain poorly understood and the role of the neuromuscular junction (NMJ) in this group of disorders is particularly overlooked, especially in humans, when these diseases are comparatively rare. However, elucidating the development, function and degeneration of the NMJ is essential to uncover its contribution to neuromuscular disorders, and to explore potential therapeutic avenues to treat these devastating diseases. Until now, an understanding of the role of the NMJ in disease pathogenesis has been hindered by inherent differences between rodent and human NMJs: stark contrasts in body size and corresponding differences in associated axon length underpin some of the translational issues in animal models of neuromuscular disease. Comparative studies in large mammalian models, including examination of naturally occurring, highly prevalent animal diseases and evaluation of their treatment, might provide more relevant insights into the pathogenesis and therapy of equivalent human diseases. This review argues that large animal models offer great potential to enhance our understanding of the neuromuscular system in health and disease, and in particular, when dealing with diseases for which nerve length dependency might underly the pathogenesis.


Assuntos
Axônios , Junção Neuromuscular , Animais , Humanos , Mamíferos , Junção Neuromuscular/patologia
8.
J Anat ; 241(5): 1133-1147, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36087283

RESUMO

Morphological study of the neuromuscular junction (NMJ), a specialised peripheral synapse formed between a lower motor neuron and skeletal muscle fibre, has significantly contributed to the understanding of synaptic biology and neuromuscular disease pathogenesis. Rodent NMJs are readily accessible, and research into conditions such as amyotrophic lateral sclerosis (ALS), Charcot-Marie-Tooth disease (CMT), and spinal muscular atrophy (SMA) has relied heavily on experimental work in these small mammals. However, given that nerve length dependency is an important feature of many peripheral neuropathies, these rodent models have clear shortcomings; large animal models might be preferable, but their size presents novel anatomical challenges. Overcoming these constraints to study the NMJ morphology of large mammalian distal limb muscles is of prime importance to increase cross-species translational neuromuscular research potential, particularly in the study of long motor units. In the past, NMJ phenotype analysis of large muscle bodies within the equine distal pelvic limb, such as the tibialis cranialis, or within muscles of high fibrous content, such as the soleus, has posed a distinct experimental hurdle. We optimised a technique for NMJ location and dissection from equine pelvic limb muscles. Using a quantification method validated in smaller species, we demonstrate their morphology and show that equine NMJs can be reliably dissected, stained and analysed. We reveal that the NMJs within the equine soleus have distinctly different morphologies when compared to the extensor digitorum longus and tibialis cranialis muscles. Overall, we demonstrate that equine distal pelvic limb muscles can be regionally dissected, with samples whole-mounted and their innervation patterns visualised. These methods will allow the localisation and analysis of neuromuscular junctions within the muscle bodies of large mammals to identify neuroanatomical and neuropathological features.


Assuntos
Corantes , Doenças do Sistema Nervoso Periférico , Animais , Cavalos , Mamíferos , Neurônios Motores/patologia , Fibras Musculares Esqueléticas , Músculo Esquelético/patologia , Junção Neuromuscular/patologia , Doenças do Sistema Nervoso Periférico/patologia
9.
Nucleic Acids Res ; 47(18): e106, 2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31372658

RESUMO

Biological research is relying on increasingly complex genetic systems and circuits to perform sophisticated operations in living cells. Performing these operations often requires simultaneous delivery of many genes, and optimizing the stoichiometry of these genes can yield drastic improvements in performance. However, sufficiently sampling the large design space of gene expression stoichiometries in mammalian cells using current methods is cumbersome, complex, or expensive. We present a 'poly-transfection' method as a simple yet high-throughput alternative that enables comprehensive evaluation of genetic systems in a single, readily-prepared transfection sample. Each cell in a poly-transfection represents an independent measurement at a distinct gene expression stoichiometry, fully leveraging the single-cell nature of transfection experiments. We first benchmark poly-transfection against co-transfection, showing that titration curves for commonly-used regulators agree between the two methods. We then use poly-transfections to efficiently generate new insights, for example in CRISPRa and synthetic miRNA systems. Finally, we use poly-transfection to rapidly engineer a difficult-to-optimize miRNA-based cell classifier for discriminating cancerous cells. One-pot evaluation enabled by poly-transfection accelerates and simplifies the design of genetic systems, providing a new high-information strategy for interrogating biology.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Transfecção/métodos , Animais , Sistemas CRISPR-Cas/genética , Expressão Gênica/genética , Humanos , MicroRNAs/genética
10.
Appetite ; 166: 105429, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062175

RESUMO

African American women, in particular, have learned to navigate through a food consumption landscape that purposefully, and often aggressively, limits their choices and stigmatizes their resulting physical appearance, and renders them collectively unattractive and unworthy. While American women are challenged to subscribe to traditional slim body standards, a faction of Americans have differing opinions. African American (AA) women celebrate larger body types and defy weight stigma. When African Americans make food choices, taste and cost are not the only factors influencing those choices; the cultural role of food is also considered. We conducted semi-structured interviews with 12 African American girls to identify some of the consequences of this consumption practice that challenges what we argue is a hegemonic taste regime surrounding body size. This work further elucidates the ways in which the African American community has operationalized the concept of cultural capital around the issues of body image to create what we suggest is a type of emotional well-being. In addition to uncovering marketing channels promoting anti-obesity campaigns that would be more likely to capture their attention, our findings also reveal that AA girls embrace shapely bodies, despite not necessarily having one themselves, and overall possess a more positive body image than their Caucasian peers. Having shapely bodies was deemed more attractive among romantic interests and acceptable overall in the AA community regardless of the associated health risks associated with consuming unhealthy foods.


Assuntos
Negro ou Afro-Americano , População Branca , Imagem Corporal , Feminino , Preferências Alimentares , Humanos , Obesidade
11.
J Fish Biol ; 99(3): 856-874, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33913166

RESUMO

Tracking 47 post-spawned adult Atlantic salmon Salmo salar L. in a hydropower-regulated river through autumn, winter and spring revealed that winter survival was 56% and 75% in two study years, respectively, with higher mortality of males than females (50% vs. 33% and 100% vs. 13%, respectively). Some kelts (n = 7) displayed nondirected movements that were interpreted as a reconditioning period for an average of 9-17 days prior to directed downstream movements indicating the initiation of migration. Survival after the initiation of migration in spring was 83% and 94% to the hydropower dam in the first and second study years, and decreased to 60 and 63%, respectively, after dam passage. There were no further losses in the downriver reach in the second year, with the first year having a cumulative survival estimate of 53% to the river mouth. Kelts approached the dam when the spillway gates were available as a passage option most of the time (64%-75%), but some kelts arrived at the dam or had not yet passed when spillways were closed (n = 6) and the only remaining passage option was restricted to the turbines. However, all but one kelt that must have passed via turbine were successful in reaching the river mouth. Migratory delay presumably due to searching behaviour caused by low water flow was estimated at approximately 6 days as migration rates were significantly slower in the reservoir (median ± s.e. 8.5 ± 2.5 km day-1 ) than up- (29.7 ± 5.0 km day-1 ) or downriver (22.1 ± 3.1 km day-1 ). The proportion of time (median 30%) that kelts spent swimming upstream (searching behaviour) in the reservoir was a significant variable for migration success.


Assuntos
Salmo salar , Migração Animal , Animais , Feminino , Masculino , Rios , Estações do Ano , Natação
12.
Am J Hum Genet ; 100(5): 706-724, 2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-28413018

RESUMO

During neurotransmission, synaptic vesicles undergo multiple rounds of exo-endocytosis, involving recycling and/or degradation of synaptic proteins. While ubiquitin signaling at synapses is essential for neural function, it has been assumed that synaptic proteostasis requires the ubiquitin-proteasome system (UPS). We demonstrate here that turnover of synaptic membrane proteins via the endolysosomal pathway is essential for synaptic function. In both human and mouse, hypomorphic mutations in the ubiquitin adaptor protein PLAA cause an infantile-lethal neurodysfunction syndrome with seizures. Resulting from perturbed endolysosomal degradation, Plaa mutant neurons accumulate K63-polyubiquitylated proteins and synaptic membrane proteins, disrupting synaptic vesicle recycling and neurotransmission. Through characterization of this neurological intracellular trafficking disorder, we establish the importance of ubiquitin-mediated endolysosomal trafficking at the synapse.


Assuntos
Epilepsia/genética , Proteínas/genética , Espasmos Infantis/genética , Transmissão Sináptica , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Modelos Animais de Doenças , Epilepsia/diagnóstico , Fibroblastos/metabolismo , Técnicas de Genotipagem , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Camundongos , Camundongos Transgênicos , Mutação , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Conformação Proteica , Proteínas/metabolismo , Células de Purkinje/metabolismo , Espasmos Infantis/diagnóstico , Vesículas Sinápticas/metabolismo , Transcriptoma , Ubiquitina/genética , Ubiquitina/metabolismo
13.
J Anat ; 237(5): 827-836, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32573802

RESUMO

The neuromuscular junction (NMJ)-a synapse formed between lower motor neuron and skeletal muscle fibre-represents a major focus of both basic neuroscience research and clinical neuroscience research. Although the NMJ is known to play an important role in many neurodegenerative conditions affecting humans, the vast majority of anatomical and physiological data concerning the NMJ come from lower mammalian (e.g. rodent) animal models. However, recent findings have demonstrated major differences between the cellular anatomy and molecular anatomy of human and rodent NMJs. Therefore, we undertook a comparative morphometric analysis of the NMJ across several larger mammalian species in order to generate baseline inter-species anatomical reference data for the NMJ and to identify animal models that better represent the morphology of the human NMJ in vivo. Using a standardized morphometric platform ('NMJ-morph'), we analysed 5,385 individual NMJs from lower/pelvic limb muscles (EDL, soleus and peronei) of 6 mammalian species (mouse, cat, dog, sheep, pig and human). There was marked heterogeneity of NMJ morphology both within and between species, with no overall relationship found between NMJ morphology and muscle fibre diameter or body size. Mice had the largest NMJs on the smallest muscle fibres; cats had the smallest NMJs on the largest muscle fibres. Of all the species examined, the sheep NMJ had the most closely matched morphology to that found in humans. Taken together, we present a series of comprehensive baseline morphometric data for the mammalian NMJ and suggest that ovine models are likely to best represent the human NMJ in health and disease.


Assuntos
Mamíferos/anatomia & histologia , Junção Neuromuscular/anatomia & histologia , Animais , Gatos , Cães , Humanos , Camundongos
14.
J Sports Sci ; 37(12): 1338-1346, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30563419

RESUMO

The aim of the current study was to investigate positional specific physical performance and external load responses to short term fixture congestion in English professional soccer. A total of 515 match observations were categorised as G1: the first game in a week with >4 days following a previous game, G2: the second game in a week played <4 days since G1, and G3: the third game in a week played with <4 days between each of the previous games. Global positioning system and accelerometer-based metrics were partitioned into fifteen-minute epochs. These data were then analysed using a linear mixed model to assess both the within and between game positional differences. Total, low-intensity (<4.0 m·s-1), medium-intensity (MID; 4.0-5.5 m·s-1), and sprint distance (>7.0 m·s-1) were significantly different across games. No between game positional differences were identified; however, within match position specific differences were observed for measures of MID and HID. No significant differences were evident for accelerometer derived metrics between games or across positions. The current data suggests that the use of fifteen minute within game epochs enables the detection of alterations in physical output during congested schedules. The observed within game positional differences has implications for player specific conditioning and squad rotation strategies.


Assuntos
Desempenho Atlético/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Adulto , Comportamento Competitivo , Inglaterra , Sistemas de Informação Geográfica , Humanos , Modelos Lineares , Masculino , Adulto Jovem
15.
J Fish Biol ; 94(1): 40-52, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30357836

RESUMO

The diet of repeat-spawner Atlantic salmon Salmo salar was investigated using carbon and nitrogen stable-isotope values from the outer growth band of scales, which reflect the fish's consumption and growth during their most recent marine phase. Isotope values for S. salar displaying different spawning strategies were compared between and within the Miramichi and Nashwaak Rivers, New Brunswick, Canada and a Bayesian mixing model was used to infer dietary contributions from potential prey items. Significant differences in the stable-isotope values were found among spawning strategies and between rivers, indicating differences in diet and feeding area, consistent with hypotheses. Bayesian mixing model results inferred the main prey items consumed during marine feeding by S. salar to consist of hyperiid amphipods and capelin Mallotus villosus for repeat alternate spawners from both rivers, sandlance Ammodytes sp. for repeat consecutive spawners from the Miramichi River and amphipods for repeat consecutive spawners from the Nashwaak River. These results demonstrate the diversity of feeding tactics among S. salar spawning strategies from the same river and between populations from different rivers. Accounting for differences in prey availability and the subsequent impact on S. salar diet and spawner return rates (i.e., marine survival) will facilitate the application of ecosystem-based management practices, such as ensuring that fisheries for forage species do not indirectly adversely affect S. salar return rates.


Assuntos
Dieta , Salmo salar/fisiologia , Comportamento Sexual Animal , Animais , Teorema de Bayes , Isótopos de Carbono/análise , Ecossistema , Novo Brunswick , Isótopos de Nitrogênio/análise , Osmeriformes , Rios
16.
Hum Mol Genet ; 25(13): 2853-2861, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27170316

RESUMO

Spinal muscular atrophy (SMA) is a neuromuscular disease caused by low levels of SMN protein, primarily affecting lower motor neurons. Recent evidence from SMA and related conditions suggests that glial cells can influence disease severity. Here, we investigated the role of glial cells in the peripheral nervous system by creating SMA mice selectively overexpressing SMN in myelinating Schwann cells (Smn-/-;SMN2tg/0;SMN1SC). Restoration of SMN protein levels restricted solely to Schwann cells reversed myelination defects, significantly improved neuromuscular function and ameliorated neuromuscular junction pathology in SMA mice. However, restoration of SMN in Schwann cells had no impact on motor neuron soma loss from the spinal cord or ongoing systemic and peripheral pathology. This study provides evidence for a defined, intrinsic contribution of glial cells to SMA disease pathogenesis and suggests that therapies designed to include Schwann cells in their target tissues are likely to be required in order to rescue myelination defects and associated disease symptoms.


Assuntos
Neuroglia/metabolismo , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Proteína 1 de Sobrevivência do Neurônio Motor/metabolismo , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Neurônios Motores/metabolismo , Atrofia Muscular Espinal/metabolismo , Bainha de Mielina/metabolismo , Degeneração Neural/patologia , Doenças Neuromusculares/patologia , Junção Neuromuscular/metabolismo , Células de Schwann/metabolismo , Medula Espinal/metabolismo , Proteína 2 de Sobrevivência do Neurônio Motor/genética , Proteína 2 de Sobrevivência do Neurônio Motor/metabolismo
17.
Hum Mol Genet ; 25(20): 4389-4404, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28173151

RESUMO

Rett syndrome (RTT) is a severe genetic disorder resulting from mutations in the X-linked MECP2 gene. MeCP2 protein is highly expressed in the nervous system and deficiency in the mouse central nervous system alone recapitulates many features of the disorder. This suggests that RTT is primarily a neurological disorder, although the protein is reportedly widely expressed throughout the body. To determine whether aspects of the RTT phenotype that originate in non-neuronal tissues might have been overlooked, we generated mice in which Mecp2 remains at near normal levels in the nervous system, but is severely depleted elsewhere. Comparison of these mice with wild type and globally MeCP2-deficient mice showed that the majority of RTT-associated behavioural, sensorimotor, gait and autonomic (respiratory and cardiac) phenotypes are absent. Specific peripheral phenotypes were observed, however, most notably hypo-activity, exercise fatigue and bone abnormalities. Our results confirm that the brain should be the primary target for potential RTT therapies, but also strongly suggest that some less extreme but clinically significant aspects of the disorder arise independently of defects in the nervous system.


Assuntos
Encéfalo/metabolismo , Proteína 2 de Ligação a Metil-CpG/genética , Fenótipo , Síndrome de Rett/metabolismo , Síndrome de Rett/patologia , Animais , Encéfalo/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Especificidade de Órgãos , Síndrome de Rett/genética
18.
Clin Gastroenterol Hepatol ; 15(11): 1758-1767.e11, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28625816

RESUMO

BACKGROUND & AIMS: On the basis of the Next Accreditation System, trainee assessment should occur on a continuous basis with individualized feedback. We aimed to validate endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) learning curves among advanced endoscopy trainees (AETs) by using a large national sample of training programs and to develop a centralized database that allows assessment of performance in relation to peers. METHODS: ASGE recognized training programs were invited to participate, and AETs were graded on ERCP and EUS exams by using a validated competency assessment tool that assesses technical and cognitive competence in a continuous fashion. Grading for each skill was done by using a 4-point scoring system, and a comprehensive data collection and reporting system was built to create learning curves by using cumulative sum analysis. Individual results and benchmarking to peers were shared with AETs and trainers quarterly. RESULTS: Of the 62 programs invited, 20 programs and 22 AETs participated in this study. At the end of training, median number of EUS and ERCP performed/AET was 300 (range, 155-650) and 350 (125-500), respectively. Overall, 3786 exams were graded (EUS, 1137; ERCP-biliary, 2280; ERCP-pancreatic, 369). Learning curves for individual end points and overall technical/cognitive aspects in EUS and ERCP demonstrated substantial variability and were successfully shared with all programs. The majority of trainees achieved overall technical (EUS, 82%; ERCP, 60%) and cognitive (EUS, 76%; ERCP, 100%) competence at conclusion of training. CONCLUSIONS: These results demonstrate the feasibility of establishing a centralized database to report individualized learning curves and confirm the substantial variability in time to achieve competence among AETs in EUS and ERCP. ClinicalTrials.gov: NCT02509416.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/métodos , Competência Clínica , Endossonografia/métodos , Gastroenterologia/educação , Gastroenteropatias/diagnóstico , Curva de Aprendizado , Humanos , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos
19.
J Chem Phys ; 147(21): 214306, 2017 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-29221376

RESUMO

Increasing interest in the thermodynamics of small and/or isolated systems, in combination with recent observations of negative temperatures of atoms in ultracold optical lattices, has stimulated the need for estimating the conventional, canonical temperature Tcconv of systems in equilibrium with heat baths using eigenstate-specific temperatures (ESTs). Four distinct ESTs-continuous canonical, discrete canonical, continuous microcanonical, and discrete microcanonical-are accordingly derived for two-level paramagnetic spin lattices (PSLs) in external magnetic fields. At large N, the four ESTs are intensive, equal to Tcconv, and obey all four laws of thermodynamics. In contrast, for N < 1000, the ESTs of most PSL eigenstates are non-intensive, differ from Tcconv, and violate each of the thermodynamic laws. Hence, in spite of their similarities to Tcconv at large N, the ESTs are not true thermodynamic temperatures. Even so, each of the ESTs manifests a unique functional dependence on energy which clearly specifies the magnitude and direction of their deviation from Tcconv; the ESTs are thus good temperature estimators for small PSLs. The thermodynamic uncertainty relation is obeyed only by the ESTs of small canonical PSLs; it is violated by large canonical PSLs and by microcanonical PSLs of any size. The ESTs of population-inverted eigenstates are negative (positive) when calculated using Boltzmann (Gibbs) entropies; the thermodynamic implications of these entropically induced differences in sign are discussed in light of adiabatic invariance of the entropies. Potential applications of the four ESTs to nanothermometers and to systems with long-range interactions are discussed.

20.
Res Sports Med ; 25(4): 437-450, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28795591

RESUMO

To investigate the anatomical distribution of linear and rotational forces during the tackle scenario, male rugby players performed a total of 48 trials, as ball carrier or tackler. Participants wore headgear accommodating three global positioning system units measuring uniaxial acceleration at the occipital region (OR), left tempero-parietal (LT-PR) and right tempero-parietal region (RT-PR). An additional unit was located at the cervico-thoracic spinal region in a custom vest. There was a significant main effect for tackle condition (P < 0.001), with the tackler exposed to significantly greater load than the ball carrier, supporting epidemiological observations. A repeated measure general linear model also revealed a significant (P < 0.001) main effect for unit location upon 3D load, with significantly higher load at the CSR (1.63 ± 0.54 a.u.) and OR (1.67 ± 0.94 a.u.) units when compared to the LT-PR (1.23 ± 0.39 a.u.) and RT-PR (1.21 ± 0.44 a.u.) units. The anatomical specificity in loading supports epidemiological observations and provides an insight into potential concussion aetiology.


Assuntos
Concussão Encefálica/etiologia , Futebol Americano/lesões , Suporte de Carga , Aceleração , Fenômenos Biomecânicos , Cabeça , Dispositivos de Proteção da Cabeça , Humanos , Modelos Lineares , Masculino , Pescoço , Fatores de Risco , Rotação , Coluna Vertebral , Adulto Jovem
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