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1.
Dev Biol ; 512: 35-43, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710381

RESUMEN

The larval stage of the Drosophila melanogaster life cycle is characterized by rapid growth and nutrient storage that occur over three instar stages separated by molts. In the third instar, the steroid hormone ecdysone drives key developmental processes and behaviors that occur in a temporally-controlled sequence and prepare the animal to undergo metamorphosis. Accurately staging Drosophila larvae within the final third instar is critical due to the rapid developmental progress at this stage, but it is challenging because the rate of development varies widely across a population of animals even if eggs are laid within a short period of time. Moreover, many methods to stage third instar larvae are cumbersome, and inherent variability in the rate of development confounds some of these approaches. Here we demonstrate the usefulness of the Sgs3-GFP transgene, a fusion of the Salivary gland secretion 3 (Sgs3) and GFP proteins, for staging third instar larvae. Sgs3-GFP is expressed in the salivary glands in an ecdysone-dependent manner from the midpoint of the third instar, and its expression pattern changes reproducibly as larvae progress through the third instar. We show that Sgs3-GFP can easily be incorporated into experiments, that it allows collection of developmentally-equivalent individuals from a mixed population of larvae, and that its use enables precise assessment of changing levels of hormones, metabolites, and gene expression during the second half of the third instar.

2.
Animal ; 18(3): 101095, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38367311

RESUMEN

Milk markers have the potential to aid in the detection of cow disease in early lactation if the automation of milk analysis becomes commonplace. Characterising temporal profiles of milk markers in dairy cows will improve the understanding of basal concentrations in clinically healthy cows. The objective of this observational study was to characterise the variation and temporal profiles of colostrum and milk haptoglobin (Hp) and substance P concentrations within 21 days postcalving in clinically healthy multiparous Holstein dairy cows. Ninety Holstein dairy cows from a commercial dairy herd were included. Milk samples were collected on the day of calving (day 0), and on days 1 to 4, 7, 14, and 21 postcalving and concentrations of Hp and substance P in colostrum (days 0 to 3) and milk (days 4, 7, 14, and 21) were determined using Enzyme Linked Immunosorbent assay. Haptoglobin and substance P concentrations were, on average (raw means ± SD), 0.40 ± 0.26 µg/ml and 56.2 ± 38.7 pg/ml in colostrum, respectively, and 0.23 ± 0.23 µg/ml and 37.1 ± 27.8 pg/ml in milk, respectively. Haptoglobin and substance P were elevated and greatest 1 day postcalving (least squares mean ± SE of the mean; 0.53 ± 0.05 µg/ml and 46.5 ± 3.64 pg/ml, respectively) and substance P varied widely within 21 days postcalving. The presence of substance P in dairy cow colostrum was not documented previously. Elevated concentrations of Hp and substance P immediately postcalving may be due to physiological roles these inflammatory markers have in the dairy cow or neonate or may simply represent an accumulation in colostrum before the first milk is removed.


Asunto(s)
Calostro , Leche , Embarazo , Femenino , Bovinos , Animales , Haptoglobinas , Sustancia P , Lactancia/fisiología
3.
J Immunol ; 212(1): 43-56, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37955416

RESUMEN

Serum Ab concentrations, selection for higher affinity BCRs, and generation of higher Ab affinities are important elements of immune response optimization and functions of germinal center (GC) reactions. B cell proliferation requires nutrients to support the anabolism inherent in clonal expansion. Glucose usage by mouse GC B cells has been reported to contribute little to their energy needs, with questions raised as to whether glucose uptake or glycolysis increases in GC B cells compared with their naive precursors. Indeed, metabolism can be highly flexible, such that supply shortage along one pathway may be compensated by increased flux on others. We now show that reduction of the glucose transporter GLUT1 in mice after establishment of a preimmune B cell repertoire, even after initiation of the GC B cell gene expression program, decreased initial GC B cell population numbers, affinity maturation, and plasma cell outputs. Glucose oxidation was heightened in GC B cells, but this hexose flowed more into the pentose phosphate pathway, whose activity was important in controlling reactive oxygen species (ROS) and Ab-secreting cell production. In modeling how glucose usage by B cells promotes the Ab response, the control of ROS appeared insufficient. Surprisingly, the combination of galactose, which mitigated ROS, with provision of mannose, an efficient precursor to glycosylation, supported robust production of and normal Ab secretion by Ab-secreting cells under glucose-free conditions. Collectively, the findings indicate that GCs depend on normal glucose influx, especially in plasma cell production, but reveal an unexpected metabolic flexibility in hexose requirements.


Asunto(s)
Centro Germinal , Glucosa , Ratones , Animales , Glucosa/metabolismo , Especies Reactivas de Oxígeno , Anticuerpos , Diferenciación Celular
4.
Biosens Bioelectron ; 248: 115971, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38154328

RESUMEN

Apomorphine is a dopamine agonist that is used for the management of Parkinson's disease and has been proven to effectively decrease the off-time duration, where the symptoms recur, in Parkinson's disease patients. This paper describes the design and fabrication of the first potentiometric sensor for the determination of apomorphine in bulk and human plasma samples. The fabrication protocol involves stereolithographic 3D printing, which is a unique tool for the rapid fabrication of low-cost sensors. The solid-contact apomorphine ion-selective electrode combines a carbon-mesh/thermoplastic composite as the ion-to-electron transducer and a 3D printed ion-selective membrane, doped with the ionophore calix[6]arene. The sensor selectively measures apomorphine in the presence of other biologically present cations - sodium, potassium, magnesium, and calcium - as well as the commonly prescribed Parkinson's pharmaceutical, levodopa (L-Dopa). The sensor demonstrated a linear, Nernstian response, with a slope of 58.8 mV/decade over the range of 5.0 mM-9.8 µM, which covers the biologically (and pharmaceutically) relevant ranges, with a limit of detection of 2.51 µM. Moreover, the apomorphine sensor exhibited good stability (minimal drift of just 188 µV/hour over 10 h) and a shelf-life of almost 4 weeks. Experiments performed in the presence of albumin, the main plasma protein to which apomorphine binds, demonstrate that the sensor responds selectively to free-apomorphine (i.e., not bound or complexed forms). The utility of the sensor was confirmed through the successful determination of apomorphine in spiked human plasma samples.


Asunto(s)
Técnicas Biosensibles , Enfermedad de Parkinson , Humanos , Apomorfina , Enfermedad de Parkinson/tratamiento farmacológico , Electrodos de Iones Selectos , Preparaciones Farmacéuticas , Potenciometría
5.
R Soc Open Sci ; 10(10): 230968, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37830017

RESUMEN

Most living reptile diversity is concentrated in Squamata (lizards, including snakes), which have poorly known origins in space and time. Recently, †Cryptovaranoides microlanius from the Late Triassic of the United Kingdom was described as the oldest crown squamate. If true, this result would push back the origin of all major lizard clades by 30-65 Myr and suggest that divergence times for reptile clades estimated using genomic and morphological data are grossly inaccurate. Here, we use computed tomography scans and expanded phylogenetic datasets to re-evaluate the phylogenetic affinities of †Cryptovaranoides and other putative early squamates. We robustly reject the crown squamate affinities of †Cryptovaranoides, and instead resolve †Cryptovaranoides as a potential member of the bird and crocodylian total clade, Archosauromorpha. Bayesian total evidence dating supports a Jurassic origin of crown squamates, not Triassic as recently suggested. We highlight how features traditionally linked to lepidosaurs are in fact widespread across Triassic reptiles. Our study reaffirms the importance of critically choosing and constructing morphological datasets and appropriate taxon sampling to test the phylogenetic affinities of problematic fossils and calibrate the Tree of Life.

6.
bioRxiv ; 2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37745429

RESUMEN

Antibody secretion into sera, selection for higher affinity BCR, and the generation of higher Ab affinities are important elements of immune response optimization, and a core function of germinal center reactions. B cell proliferation requires nutrients to support the anabolism inherent in clonal expansion. Glucose usage by GC B cells has been reported to contribute little to their energy needs, with questions raised as to whether or not glucose uptake or glycolysis increases in GC B cells compared to their naïve precursors. Indeed, metabolism can be highly flexible, such that supply shortage along one pathway may be compensated by increased flux on others. We now show that elimination of the glucose transporter GLUT1 after establishment of a pre-immune B cell repertoire, even after initiation of the GC B cell gene expression program, decreased initial GC B cell population numbers, affinity maturation, and PC outputs. Glucose oxidation was heightened in GC B cells, but this hexose flowed more into the pentose phosphate pathway (PPP), whose activity was important in controlling reactive oxygen (ROS) and ASC production. In modeling how glucose usage by B cells promotes the Ab response, the control of ROS appeared insufficient. Surprisingly, the combination of galactose, which mitigated ROS, with provision of mannose - an efficient precursor to glycosylation - supported robust production of and normal Ab secretion by ASC under glucose-free conditions. Collectively, the findings indicate that GC depend on normal glucose influx, especially in PC production, but reveal an unexpected metabolic flexibility in hexose requirements. KEY POINTS: Glucose influx is critical for GC homeostasis, affinity maturation and the generation of Ab-secreting cells.Plasma cell development uses the Pentose Phosphate Pathway, and hexose sugars maintain redox homeostasis.PCs can develop and achieve robust Ab secretion in the absence of glucose using a combination of hexose alternatives.

7.
Digit Health ; 9: 20552076231183555, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37426589

RESUMEN

Objective: Mild traumatic brain injuries (mTBIs) are common and may result in persisting symptoms. Mobile health (mHealth) applications enhance treatment access and rehabilitation. However, there is limited evidence to support mHealth applications for individuals with an mTBI. The primary purpose of this study was to evaluate user experiences and perceptions of the Parkwood Pacing and Planning™ application, an mHealth application developed to help individuals manage their symptoms following an mTBI. The secondary purpose of this study was to identify strategies to improve the application. This study was conducted as part of the development process for this application. Methods: A mixed methods co-design encompassing an interactive focus group and a follow-up survey was conducted with patient and clinician-participants (n = 8, four per group). Each group participated in a focus group consisting of an interactive scenario-based review of the application. Additionally, participants completed the Internet Evaluation and Utility Questionnaire (UQ). Qualitative analysis on the interactive focus group recordings and notes was performed using phenomenological reflection through thematic analyses. Quantitative analysis included descriptive statistics of demographic information and UQ responses. Results: On average, clinician and patient-participants positively rated the application on the UQ (4.0 ± .3, 3.8 ± .2, respectively). User experiences and recommendations for improving the application were categorized into four themes: simplicity, adaptability, conciseness, and familiarity. Conclusion: Preliminary analyses indicates patients and clinicians have a positive experience when using the Parkwood Pacing and Planning™ application. However, modifications that improve simplicity, adaptability, conciseness, and familiarity may further improve the user's experience.

8.
BMC Neurol ; 23(1): 266, 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37442947

RESUMEN

BACKGROUND: Most individuals living with spinal cord injuries/diseases (SCI/D) or stroke experience at least one fall each year; hence, the development of interventions and technologies that target balance control is needed. The purpose of this study was to identify and explore the priorities for balance-focused interventions and technologies from the perspectives of end-users to assist with the design of an intervention that combines functional electrical stimulation (FES) with visual feedback training for standing balance. METHODS: Two individuals with SCI/D, one individual with stroke, two physical therapists (PT) and one hospital administrator were recruited. Participants attended three focus group meetings that followed a participatory co-design approach. A semi-structured interview guide, developed from the FAME (Feasibility, Appropriateness, Meaningfulness, Effectiveness, Economic Evidence) framework, was used to lead the discussion, querying participants' experiences with balance deficits and interventions, and FES. Meetings were audio-recorded and transcribed verbatim. An iterative and reflexive inductive thematic analysis was applied to the transcripts by three researchers. RESULTS: Four themes were identified: (1) Balance is meaningful for daily life and rehabilitation. Participants acknowledged various factors influencing balance control and how balance deficits interfered with participation in activities. End-users stressed the importance of continuing to work on one's balance after discharge from hospital-based rehabilitation. (2) Desired characteristics of balance interventions. Participants explained that balance interventions should be tailored to an individual's unique needs and goals, relevant to their lives, balance their safety and risk, and be engaging. (3) Prior experiences with FES to inform future therapeutic use. Participants with stroke or SCI/D described initial apprehension with FES, but experienced numerous benefits that motivated them to continue with FES. Challenges with FES were mentioned, including wires, cost, and time of set up. (4) Potential role of FES in balance interventions. Participants felt that FES would complement balance interventions; however, they had not experienced this combination of therapies previously. CONCLUSIONS: End-users described how their experiences with balance deficits, rehabilitation, and FES informed their priorities for balance interventions. The findings inform the design and implementation of future balance interventions for individuals with SCI/D or stroke, including an intervention involving FES and visual feedback training.


Asunto(s)
Terapia por Estimulación Eléctrica , Traumatismos de la Médula Espinal , Accidente Cerebrovascular , Humanos , Traumatismos de la Médula Espinal/rehabilitación , Terapia por Ejercicio , Accidente Cerebrovascular/terapia , Estimulación Eléctrica
9.
Anal Chim Acta ; 1273: 341546, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37423672

RESUMEN

Parkinson's disease (PD) is one of the leading neurological disorders negatively impacting health on a global scale. Patients diagnosed with PD require frequent monitoring, prescribed medications, and therapy for extended periods as symptom severity worsens. The primary pharmaceutical treatment for PD patients is levodopa (L-Dopa) which reduces many symptoms experienced by PD patients (e.g., tremors, cognitive ability, motor dysfunction, etc.) through the regulation of dopamine levels in the body. Herein, the first detection of L-Dopa in human sweat using a low-cost 3D printed sensor with a simple and rapid fabrication protocol combined with a portable potentiostat wirelessly connected to a smartphone via Bluetooth is reported. By combining saponification and electrochemical activation into a single protocol, the optimized 3D printed carbon electrodes were able to simultaneously detect uric acid and L-Dopa throughout their biologically relevant ranges. The optimized sensors provided a sensitivity of 83 ± 3 nA/µM from 24 µM to 300 nM L-Dopa. Common physiological interferents found in sweat (e.g., ascorbic acid, glucose, caffeine) showed no influence on the response for L-Dopa. Lastly, a percent recovery of L-Dopa in human sweat using a smartphone-assisted handheld potentiostat resulted in the recovery of 100 ± 8%, confirming the ability of this sensor to accurately detect L-Dopa in sweat.


Asunto(s)
Levodopa , Enfermedad de Parkinson , Humanos , Sudor , Teléfono Inteligente , Enfermedad de Parkinson/tratamiento farmacológico , Impresión Tridimensional
10.
J Phys Chem B ; 127(26): 5772-5788, 2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-37357785

RESUMEN

Fluorescent proteins (FPs) have had an enormous impact on molecular and cellular biology and are employed in a wide range of studies of molecular structure and dynamics. Yet, only a modest number of papers have published molecular dynamics (MD) parameters describing FPs. And despite the development of a wide range of FPs, there has been no careful development of MD parameters across a series of FPs. In this work, we present MD parameters describing six fluorescent protein chromophores (EGFP, EBFP, EYFP, ECFP, mCherry, and DsRed) for use with the Cornell et al. ( J. Am. Chem. Soc. 1995, 117, 5179-5197) family of AMBER force fields, including ff14SB and ff19SB. We explore a wide range of solvent dielectric constants for determining the chromophore equilibrium geometry and evaluate the impact of the modeled solvent on the final atomic charges. We also present our methodological approach in which we considered all six chromophores together with a focus on modularity, transferability, and balance with existing force fields. The parameters given here make it easy to employ MD simulations to study any of the six systems, whereas the methodology makes it easy for anyone to extend this work to develop consistent parameters for additional fluorescent proteins. The results of our own MD simulations are presented, showing that the classical MD parameters yield chromophore structural distributions that compare well with QM/MM simulations.


Asunto(s)
Simulación de Dinámica Molecular , Estructura Molecular , Solventes
11.
Curr Opin Clin Nutr Metab Care ; 26(3): 210-218, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36942895

RESUMEN

PURPOSE OF REVIEW: Systemic cancer therapy-associated skeletal muscle wasting is emerging as a powerful impetus to the overall loss of skeletal muscle experienced by patients with cancer. This review explores the clinical magnitude and biological mechanisms of muscle wasting during systemic cancer therapy to illuminate this adverse effect. Emerging strategies for mitigation are also discussed. RECENT FINDINGS: Clinical findings include precise, specific measures of muscle loss over the course of chemotherapy, targeted therapy and immunotherapy. All these therapeutic classes associate with quantitatively important muscle loss, independent of tumor response. Parallel experimental studies provide understanding of the specific molecular basis of wasting, which can include inhibition of protein synthesis, proliferation and differentiation, and activation of inflammation, reactive oxygen species, autophagy, mitophagy, apoptosis, protein catabolism, fibrosis and steatosis in muscle. Strategies to mitigate these muscle-specific adverse effects of cancer therapy remain in the earliest stages of development. SUMMARY: The adverse side effect of cancer therapy on skeletal muscle has been largely ignored in the development of cancer therapeutics. Given the extent to which loss of muscle mass and function can bear on patients' function and quality of life, protection/mitigation of these side effects is a research priority.


Asunto(s)
Miotoxicidad , Neoplasias , Humanos , Miotoxicidad/metabolismo , Miotoxicidad/patología , Calidad de Vida , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Neoplasias/metabolismo
12.
Spinal Cord Ser Cases ; 9(1): 1, 2023 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-36646680

RESUMEN

STUDY DESIGN: Cross-sectional equipment inventory. OBJECTIVES: The objective of this study was to describe the equipment used in activity-based therapy (ABT) programs for individuals with spinal cord injury or disorder (SCI/D) across Canada. SETTINGS: Publicly funded and private SCI/D care settings. METHODS: A survey on equipment available for ABT for different therapeutic goals was answered by Canadian sites providing SCI/D rehabilitation. Information about the setting and type of client were also collected. The survey results were compiled into an inventory of the reported types and use of ABT related equipment, with equipment grouped into varying levels of technology. Descriptive statistics and qualitative descriptive analysis were used to answer the questions: (1) 'who' used the equipment, (2) 'what' types of equipment are used, (3) 'why' (i.e., for which therapeutic goals), and (4) 'how' it is used. RESULTS: Twenty-two sites from eight Canadian provinces completed the survey. Reported equipment was classified into 5 categories (from low to high-tech). Most equipment reported was used to train balance. The high-tech equipment reported as available, was mostly used for walking training and strengthening of the lower limbs. Low-tech equipment was reported as being used most frequently, while high-tech devices, although available, were reported as infrequently or rarely used. CONCLUSIONS: A large spectrum of equipment with varying levels of technology were reported as available, but were inconsistently used to provide ABT interventions across sites. In order to increase the clinical use of available equipment for ABT, education tools such as protocols regarding ABT principles and implementation are needed.


Asunto(s)
Traumatismos de la Médula Espinal , Caminata , Humanos , Estudios Transversales , Canadá , Traumatismos de la Médula Espinal/rehabilitación , Tecnología
13.
Physiother Theory Pract ; 39(2): 395-404, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34895020

RESUMEN

BACKGROUND: Parkinson's disease (PD) can affect hand function since the beginning of the motor symptoms. OBJECTIVE: To compare the ability of different hand function tests to: 1) distinguish individuals with PD from healthy controls; 2) differentiate stages of the disease; and 3) indicate changes over time due to disease progression. METHODS: Twenty-four individuals with PD (Hoehn and Yahr: I-III) and 24 age- and sex-matched controls performed the Jebsen-Taylor Hand Function Test (JTHFT), the Nine-Hole Peg Test (9HPT), and the maximum grip and the maximum pinch strength tests using their right and left hands. Eight individuals with PD (six females and two males) were reassessed after 18 months. The ROC analyses and Mann-Whitney U tests (for disease progression) using the average performance of the hands were done. RESULTS: Individuals with PD presented worse test performances than controls, except for the writing subtest of the JTHFT and the grip strength test. The JTHFT without the writing subtest (JTHFTnoW) was the most accurate to discriminate PD from controls (AUC = 0.899; sensitivity 75% and specificity 95.8%). The 9HPT and the simulated feeding and moving large, light objects JTHFT subtests were sensitive to distinguish stages, while the 9HPT, the moving small, common objects JTHFT subtest, and the grip strength were sensitive to changes with disease progression. CONCLUSION: The JTHFTnoW was highly discriminative of the hand function impairments in PD. TwoJTHFT subtests were the most sensitives to distinguish PD stages (i.e. simulated feeding JTHFT subtest) and disease progression (i.e. moving small, common objects JTHFT subtest).


Asunto(s)
Enfermedad de Parkinson , Femenino , Humanos , Masculino , Mano , Fuerza de la Mano , Enfermedad de Parkinson/diagnóstico , Extremidad Superior , Destreza Motora , Estudios de Casos y Controles
14.
J Spinal Cord Med ; 46(1): 6-25, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-33596167

RESUMEN

CONTEXT: Endocrine-metabolic disease (EMD) is associated with functional disability, social isolation, hospitalization and even death in individuals living with a chronic spinal cord injury (SCI). There is currently very low-quality evidence that rehabilitation interventions can reduce EMD risk during chronic SCI. Non-randomized trials and alternative study designs are excluded from traditional knowledge synthesis. OBJECTIVE: To characterize evidence from level 3-4 studies evaluating rehabilitation interventions for their effectiveness to improve EMD risk in community-dwelling adults with chronic SCI. METHODS: Systematic searches of MEDLINE PubMed, EMBASE Ovid, CINAHL, Cochrane Database of Systematic Reviews, and PsychInfo were completed. All longitudinal trials, prospective cohort, case-control studies, and case series evaluating the effectiveness of rehabilitation/therapeutic interventions to modify/associate with EMD outcomes in adults with chronic SCI were eligible. Two authors independently selected studies and abstracted data. Mean changes from baseline were reported for EMD outcomes. The Downs and Black Checklist was used to rate evidence quality. RESULTS: Of 489 articles identified, 44 articles (N = 842) were eligible for inclusion. Individual studies reported statistically significant effects of electrical stimulation-assisted training on lower-extremity bone outcomes, and the combined effects of exercise and dietary interventions to improve body composition and cardiometabolic biomarkers (lipid profiles, glucose regulation). In contrast, there were also reports of no clinically important changes in EMD outcomes, suggesting lower quality evidence (study bias, inconsistent findings). CONCLUSION: Longitudinal multicentre pragmatic studies involving longer-term exercise and dietary intervention and follow-up periods are needed to fully understand the impact of these rehabilitation approaches to mitigate EMD risk. Our broad evaluation of prospective cohort and case-control studies provides new perspectives on alternative study designs, a multi-impairment paradigm approach of studying EMD outcomes, and knowledge gaps related to SCI rehabilitation.


Asunto(s)
Enfermedades del Sistema Endocrino , Enfermedades Metabólicas , Traumatismos de la Médula Espinal , Adulto , Humanos , Terapia por Ejercicio , Estudios Prospectivos , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/rehabilitación , Revisiones Sistemáticas como Asunto
15.
J Laryngol Otol ; 137(5): 506-514, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35995754

RESUMEN

OBJECTIVE: This study aimed to analyse whether referral for specialist balance testing influences diagnosis and management of patients with dizziness. METHOD: This was a retrospective study examining patients referred for vestibular function testing between 1 January 2018 and 30 June 2018. RESULTS: A total of 101 patients were referred, with 69 patients (68.3 per cent) receiving a preliminary 'pre-vestibular function testing balance diagnosis', which included benign paroxysmal positional vertigo (32.7 per cent), Ménière's disease (13.8 per cent) and migraine (14.9 per cent). Following vestibular function testing, revised diagnoses were achieved for 54 patients (53.5 per cent), including benign paroxysmal positional vertigo (14.9 per cent), Ménière's disease (3.0 per cent) and migraine (10.9 per cent). Pre-vestibular function testing balance diagnoses were confirmed for 32.4 per cent of patients. If no pre-vestibular function testing suspected diagnosis was provided, vestibular function testing was significantly more likely to be inconclusive. Following vestibular function testing, 38.6 per cent were discharged, 21.7 per cent were referred to another specialty and treatment was commenced for 17.8 per cent of patients. CONCLUSION: Referral for vestibular function testing has a role when attempting to answer a clear clinical question. Diagnosing the underlying aetiology of complex imbalance is challenging, but diagnosis can be assisted by judicious use of vestibular function testing.


Asunto(s)
Enfermedad de Meniere , Trastornos Migrañosos , Humanos , Vértigo Posicional Paroxístico Benigno/diagnóstico , Estudios Retrospectivos , Mareo/diagnóstico , Mareo/etiología , Trastornos Migrañosos/diagnóstico , Trastornos Migrañosos/complicaciones
16.
Immunohorizons ; 6(12): 837-850, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36547387

RESUMEN

Hematopoiesis integrates cytokine signaling, metabolism, and epigenetic modifications to regulate blood cell generation. These processes are linked, as metabolites provide essential substrates for epigenetic marks. In this study, we demonstrate that ATP citrate lyase (Acly), which metabolizes citrate to generate cytosolic acetyl-CoA and is of clinical interest, can regulate chromatin accessibility to limit myeloid differentiation. Acly was tested for a role in murine hematopoiesis by small-molecule inhibition or genetic deletion in lineage-depleted, c-Kit-enriched hematopoietic stem and progenitor cells from Mus musculus. Treatments increased the abundance of cell populations that expressed the myeloid integrin CD11b and other markers of myeloid differentiation. When single-cell RNA sequencing was performed, we found that Acly inhibitor-treated hematopoietic stem and progenitor cells exhibited greater gene expression signatures for macrophages and enrichment of these populations. Similarly, the single-cell assay for transposase-accessible chromatin sequencing showed increased chromatin accessibility at genes associated with myeloid differentiation, including CD11b, CD11c, and IRF8. Mechanistically, Acly deficiency altered chromatin accessibility and expression of multiple C/EBP family transcription factors known to regulate myeloid differentiation and cell metabolism, with increased Cebpe and decreased Cebpa and Cebpb. This effect of Acly deficiency was accompanied by altered mitochondrial metabolism with decreased mitochondrial polarization but increased mitochondrial content and production of reactive oxygen species. The bias to myeloid differentiation appeared due to insufficient generation of acetyl-CoA, as exogenous acetate to support alternate compensatory pathways to produce acetyl-CoA reversed this phenotype. Acly inhibition thus can promote myelopoiesis through deprivation of acetyl-CoA and altered histone acetylome to regulate C/EBP transcription factor family activity for myeloid differentiation.


Asunto(s)
ATP Citrato (pro-S)-Liasa , Ensamble y Desensamble de Cromatina , Epigénesis Genética , Mielopoyesis , Animales , Ratones , Acetilcoenzima A/genética , Acetilcoenzima A/metabolismo , ATP Citrato (pro-S)-Liasa/deficiencia , ATP Citrato (pro-S)-Liasa/genética , Cromatina/metabolismo , Mielopoyesis/genética
17.
Commun Biol ; 5(1): 1366, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36513703

RESUMEN

Cellular metabolism influences immune cell function, with mitochondrial fatty acid ß-oxidation and oxidative phosphorylation required for multiple immune cell phenotypes. Carnitine palmitoyltransferase 1a (Cpt1a) is considered the rate-limiting enzyme for mitochondrial metabolism of long-chain fatty acids, and Cpt1a deficiency is associated with infant mortality and infection risk. This study was undertaken to test the hypothesis that impairment in Cpt1a-dependent fatty acid oxidation results in increased susceptibility to infection. Screening the Cpt1a gene for common variants predicted to affect protein function revealed allele rs2229738_T, which was associated with pneumonia risk in a targeted human phenome association study. Pharmacologic inhibition of Cpt1a increases mortality and impairs control of the infection in a murine model of bacterial pneumonia. Susceptibility to pneumonia is associated with blunted neutrophilic responses in mice and humans that result from impaired neutrophil trafficking to the site of infection. Chemotaxis responsible for neutrophil trafficking requires Cpt1a-dependent mitochondrial fatty acid oxidation for amplification of chemoattractant signals. These findings identify Cpt1a as a potential host determinant of infection susceptibility and demonstrate a requirement for mitochondrial fatty acid oxidation in neutrophil biology.


Asunto(s)
Carnitina O-Palmitoiltransferasa , Metabolismo de los Lípidos , Neutrófilos , Animales , Humanos , Lactante , Ratones , Carnitina O-Palmitoiltransferasa/genética , Carnitina O-Palmitoiltransferasa/metabolismo , Ácidos Grasos/metabolismo , Mitocondrias/metabolismo , Neutrófilos/metabolismo
18.
Nat Commun ; 13(1): 7087, 2022 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-36446761

RESUMEN

Squamata is the most diverse clade of terrestrial vertebrates. Although the origin of pan-squamates lies in the Triassic, the oldest undisputed members of extant clades known from nearly complete, uncrushed material come from the Cretaceous. Here, we describe three-dimensionally preserved partial skulls of two new crown lizards from the Late Jurassic of North America. Both species are placed at the base of the skink, girdled, and night lizard clade Pan-Scincoidea, which consistently occupies a position deep inside the squamate crown in both morphological and molecular phylogenies. The new lizards show that several features uniting pan-scincoids with another major lizard clade, the pan-lacertoids, in trees using morphology were convergently acquired as predicted by molecular analyses. Further, the palate of one new lizard bears a handful of ancestral saurian characteristics lost in nearly all extant squamates, revealing an underappreciated degree of complex morphological evolution in the early squamate crown. We find strong evidence for close relationships between the two new species and Cretaceous taxa from Eurasia. Together, these results suggest that early crown squamates had a wide geographic distribution and experienced complicated morphological evolution even while the Rhynchocephalia, now solely represented by the tuatara, was the dominant clade of lepidosaurs.


Asunto(s)
Lagartos , Animales , Lagartos/genética , América del Norte , Cráneo , Árboles
19.
J Anat ; 241(6): 1441-1458, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36168715

RESUMEN

The rapid radiation and dispersal of crown reptiles following the end-Permian mass extinction characterizes the earliest phase of the Mesozoic. Phylogenetically, this early radiation is difficult to interpret, with polytomies near the crown node, long ghost lineages, and enigmatic origins for crown group clades. Better understanding of poorly known taxa from this time can aid in our understanding of this radiation and Permo-Triassic ecology. Here, we describe an Early Triassic specimen of the diapsid Palacrodon from the Fremouw Formation of Antarctica. While Palacrodon is known throughout the Triassic and exhibits a cosmopolitan geographic range, little is known of its evolutionary relationships. We recover Palacrodon outside of crown reptiles (Sauria) but more crownward than Youngina capensis and other late Permian diapsids. Furthermore, Palacrodon possesses anatomical features that add clarity to the evolution of the stapes within the reptilian lineage, as well as incipient adaptations for arboreality and herbivory during the earliest phases of the Permo-Triassic recovery.


Asunto(s)
Evolución Biológica , Fósiles , Animales , Regiones Antárticas , Filogenia , Extinción Biológica , Reptiles/anatomía & histología
20.
Am J Physiol Regul Integr Comp Physiol ; 323(5): R670-R681, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36121142

RESUMEN

Placenta ischemia, the initiating event in preeclampsia (PE), is associated with fetal growth restriction. Inhibition of the agonistic autoantibody against the angiotensin type 1 receptor AT1-AA, using an epitope-binding inhibitory peptide ('n7AAc') attenuates increased blood pressure at gestational day (G)19 in the clinically relevant reduced uterine perfusion pressure (RUPP) model of PE. Thus we tested the hypothesis that maternal administration of 'n7AAc' does not transfer to the fetus, improves uterine blood flow and fetal growth, and attenuates elevated placental expression of miRNAs implicated in PE and FGR. Sham or RUPP surgery was performed at G14 with vehicle or 'n7AAc' (144 µg/day) administered via an osmotic pump from G14 to G20. Maternal plasma levels of the peptide on G20 were 16.28 ± 4.4 nM, and fetal plasma levels were significantly lower at 1.15 ± 1.7 nM (P = 0.0007). The uterine artery resistance index was significantly elevated in RUPP (P < 0.0001) but was not increased in 'n7AAc'-RUPP or 'n7AAc'-Sham versus Sham. A significant reduction in fetal weight at G20 in RUPP (P = 0.003) was not observed in 'n7AAc'-RUPP. Yet, percent survival was reduced in RUPP (P = 0.0007) and 'n7AAc'-RUPP (P < 0.0002). Correlation analysis indicated the reduction in percent survival during gestation was specific to the RUPP (r = 0.5342, P = 0.043) and independent of 'n7AAc'. Placental miR-155 (P = 0.0091) and miR-181a (P = 0.0384) expression was upregulated in RUPP at G20 but was not elevated in 'n7AAc'-RUPP. Collectively, our results suggest that maternal administration of 'n7AAc' does not alter fetal growth in the RUPP implicating its potential as a therapeutic for the treatment of PE.NEW & NOTEWORTHY The seven amino acid inhibitory peptide to the AT1-AA ('n7AAc') has limited transfer to the fetus at gestational day 20, improves uterine blood flow and fetal growth in the reduced uterine perfusion pressure model of preeclampsia (PE), and does not impair fetal survival during gestation in sham-operated or placental ischemic rats. Collectively, these findings suggest that maternal administration of 'n7AAc' as an effective strategy for the treatment of PE is associated with improved outcomes in the fetus.


Asunto(s)
MicroARNs , Preeclampsia , Animales , Femenino , Humanos , Embarazo , Ratas , Aminoácidos/metabolismo , Autoanticuerpos/metabolismo , Presión Sanguínea/fisiología , Modelos Animales de Enfermedad , Epítopos/metabolismo , Desarrollo Fetal , Isquemia , MicroARNs/metabolismo , Péptidos/farmacología , Placenta/metabolismo , Ratas Sprague-Dawley , Receptor de Angiotensina Tipo 1/metabolismo , Arteria Uterina
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