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1.
Nature ; 628(8006): 195-203, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38480879

RESUMO

Sustained smouldering, or low-grade activation, of myeloid cells is a common hallmark of several chronic neurological diseases, including multiple sclerosis1. Distinct metabolic and mitochondrial features guide the activation and the diverse functional states of myeloid cells2. However, how these metabolic features act to perpetuate inflammation of the central nervous system is unclear. Here, using a multiomics approach, we identify a molecular signature that sustains the activation of microglia through mitochondrial complex I activity driving reverse electron transport and the production of reactive oxygen species. Mechanistically, blocking complex I in pro-inflammatory microglia protects the central nervous system against neurotoxic damage and improves functional outcomes in an animal disease model in vivo. Complex I activity in microglia is a potential therapeutic target to foster neuroprotection in chronic inflammatory disorders of the central nervous system3.


Assuntos
Complexo I de Transporte de Elétrons , Inflamação , Microglia , Doenças Neuroinflamatórias , Animais , Feminino , Humanos , Masculino , Camundongos , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Modelos Animais de Doenças , Transporte de Elétrons/efeitos dos fármacos , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Complexo I de Transporte de Elétrons/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Multiômica , Células Mieloides/metabolismo , Células Mieloides/patologia , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/patologia , Espécies Reativas de Oxigênio/metabolismo
2.
J Theor Biol ; 581: 111745, 2024 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-38272110

RESUMO

Migrating cells traverse a range of topographic configurations presented by the native extracellular environment to conduct their physiologic functions. It is well documented cells can modulate their behaviour in response to different topographic features, finding promising applications in biomaterial and bioimplant design. It is useful, in these areas of research, to be able to predict which topographic arrangements could be used to promote certain patterns of migration prior to laboratory experimentation. Despite a profusion of study and interest shown in these fields by experimentalists, the related modelling literature is as yet relatively sparse and tend to focus more on either cell-matrix interaction or morphological responses of cells. We propose a mathematical model for individual cell migration based on an Ornstein-Uhlenbeck process, and set out to see if the model can be used to predict migration patterns on 2-d isotropic and anisotropic topographies, whose characteristics can be broadly described as either uniform flat, uniform linear with variable ridge density or non-uniform disordered with variable feature density. Results suggest the model is capable of producing realistic patterns of migration for flat and linear topographic patterns, with calibrated output closely approximating NIH3T3 fibroblast migration behaviour derived from an experimental dataset, in which migration linearity increased with ridge density and average speed was highest at intermediate ridge densities. Exploratory results for non-uniform disordered topographies suggest cell migration patterns may adopt disorderedness present in the topography and that 'distortion' introduced to linear topographic patterns may not impede linear guidance of migration, given its magnitude is bounded within certain limits. We conclude that an Ornstein-Uhlenbeck based model for topographically influenced migration may be useful to predict patterns of migration behaviour for certain isotropic (flat) and anisotropic (linear) topographies in the NIH3T3 fibroblast cell line, but additional investigation is required to predict with confidence migration patterns for non-uniform disordered topographic arrangements.


Assuntos
Células NIH 3T3 , Camundongos , Animais , Movimento Celular
4.
Animal ; 18(8): 101256, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39106555

RESUMO

There is a balance between DM yield and feed value when choosing types of grasses on a farm depending on the acreages of farmland and types of ruminants to be fed. Therefore, optimisation of the harvest strategy for grass silage is important for profitable dairy farming. Tall fescue has high DM yield and can replace traditional grasses, such as timothy, in Northern Europe in a changing climate as it has been shown to be more drought tolerant. As differences in climate responses previously have been related to differences in cell wall structure between grass species and, consequently, in digestibility, it is highly relevant to compare these species at similar maturity stages and to investigate if a very early harvest date will diminish potential differences between the species. This study evaluated the effects of harvest date and forage species on the concentration of hydroxycinnamic acids in silages and its relationship to feed efficiency of dairy cows. Tall fescue and timothy were harvested at very early date on May 25 or at early date on May 31 in the spring growth cycle. Forty lactating dairy cows were used in a block design. Cows received 1 of 4 treatments: (1) tall fescue harvested at very early date, (2) timothy harvested at very early date, (3) tall fescue harvested at early date, and (4) timothy harvested at early date. Diets were formulated to have the same forage-to-concentrate ratio (49:51 on DM basis). Tall fescue silages showed greater concentrations of DM, ash, and CP than timothy silages. Grasses harvested at early date showed greater concentrations of NDF, ADL, and cell wall than grasses harvested at very early date. Tall fescue silages showed greater concentration of p-coumaric acid and lower in vitro organic matter digestibility (IVOMD) compared to timothy silages. Milk production and composition were not affected by treatments but cows fed tall fescue-based diets showed lower milk protein yield and greater milk urea nitrogen than when timothy-based diets were fed. Furthermore, cows receiving timothy-based diets showed greater feed efficiency compared to cows receiving tall fescue-based diets. Thus, the lower concentration of p-coumaric acid and the higher IVOMD was associated with greater feed efficiency of cows fed timothy-based diets compared to tall fescue-based diets.


Assuntos
Ração Animal , Parede Celular , Dieta , Silagem , Animais , Bovinos/fisiologia , Feminino , Silagem/análise , Ração Animal/análise , Dieta/veterinária , Phleum , Indústria de Laticínios/métodos , Lactação , Leite/química , Leite/metabolismo , Festuca , Poaceae , Fenômenos Fisiológicos da Nutrição Animal , Digestão/fisiologia
5.
Anim Conserv ; 27(2): 212-225, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38933688

RESUMO

Umbrella species and other surrogate-species approaches to conservation provide an appealing framework to extend the reach of conservation efforts beyond single species. For the umbrella species concept to be effective, populations of multiple species of concern must persist in areas protected on behalf of the umbrella species. Most assessments of the concept, however, focus exclusively on geographic overlap among umbrella and background species, and not measures that affect population persistence (e.g., habitat quality or fitness). We quantified the congruence between the habitat preferences and nesting success of a high-profile umbrella species (greater sage-grouse, Centrocercus urophasianus, hereafter "sage-grouse"), and three sympatric species of declining songbirds (Brewer's sparrow Spizella breweri, sage thasher Oreoscoptes montanus, and vesper sparrow Pooecetes gramineus) in central Wyoming, USA during 2012 - 2013. We used machine-learning methods to create data-driven predictions of sage-grouse nest-site selection and nest survival probabilities by modeling field-collected sage-grouse data relative to habitat attributes. We then used field-collected songbird data to assess whether high-quality sites for songbirds aligned with those of sage-grouse. Nest sites selected by songbirds did not coincide with sage-grouse nesting preferences, with the exception that Brewer's sparrows preferred similar nest sites to sage-grouse in 2012. Moreover, the areas that produced higher rates of songbird nest survival were unrelated to those for sage-grouse. Our findings suggest that management actions at local scales that prioritize sage-grouse nesting habitat will not necessarily enhance the reproductive success of sagebrush-associated songbirds. Measures implemented to conserve sage-grouse and other purported umbrella species at broad spatial scales likely overlap the distribution of many species, however, broad-scale overlap may not translate to fine-scale conservation benefit beyond the umbrella species itself. The maintenance of microhabitat heterogeneity important for a diversity of species of concern will be critical for a more-holistic application of the umbrella species concept.

6.
Patient Educ Couns ; 126: 108322, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38772095

RESUMO

AIM: To conduct a pilot randomized trial of an intervention to improve adolescent question-asking and provider education during paediatric diabetes visits. METHODS: Adolescents aged 11 to 17 with type 1 diabetes and their parents were enrolled from two urban tertiary paediatric clinics. Adolescents were randomised to the intervention group or control group. Adolescent consultations were audio-recorded, their HbA1c level was recorded, and they completed surveys after three clinic appointments. The intervention group completed a question prompt list and watched a video on a tablet with their parents before meeting their doctor and completed a short evaluation after each visit. RESULTS: Six consultant endocrinologists and ninety-nine adolescents and their parents participated. The intervention increased adolescents' question asking and provider education in diabetes encounters. Total patient question-asking across the 3 consultations and a higher baseline HbA1c at time one was significantly associated with HbA1c at time three. CONCLUSIONS: Question prompt lists and an educational video are useful tools to increase adolescents' question-asking and communication between adolescents and their providers. PRACTICE IMPLICATIONS: Interventions that encourage adolescents' question-asking in healthcare encounters may lead to more meaningful providers-adolescents' communication and tailored education. Interventions to improve professionals' listening, communication and educational skills are also required.


Assuntos
Comunicação , Diabetes Mellitus Tipo 1 , Relações Médico-Paciente , Humanos , Adolescente , Masculino , Projetos Piloto , Feminino , Diabetes Mellitus Tipo 1/terapia , Criança , Hemoglobinas Glicadas/análise , Educação de Pacientes como Assunto/métodos , Pais/psicologia , Inquéritos e Questionários
7.
Sleep ; 47(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38512801

RESUMO

Accumulation of amyloid-ß (Aß) plays an important role in Alzheimer's disease (AD) pathology. There is growing evidence that disordered sleep may accelerate AD pathology by impeding the physiological clearance of Aß from the brain that occurs in normal sleep. Therapeutic strategies for improving sleep quality may therefore help slow disease progression. It is well documented that the composition and dynamics of sleep are sensitive to ambient temperature. We therefore compared Aß pathology and sleep metrics derived from polysomnography in 12-month-old female 3xTg-AD mice (n = 8) exposed to thermoneutral temperatures during the light period over 4 weeks to those of age- and sex-matched controls (n = 8) that remained at normal housing temperature (22°C) during the same period. The treated group experienced greater proportions of slow wave sleep (SWS)-i.e. epochs of elevated 0.5-2 Hz EEG slow wave activity during non-rapid eye movement (NREM) sleep-compared to controls. Assays performed on mouse brain tissue harvested at the end of the experiment showed that exposure to thermoneutral temperatures significantly reduced levels of DEA-soluble (but not RIPA- or formic acid-soluble) Aß40 and Aß42 in the hippocampus, though not in the cortex. With both groups pooled together and without regard to treatment condition, NREM sleep continuity and any measure of SWS within NREM at the end of the treatment period were inversely correlated with DEA-soluble Aß40 and Aß42 levels, again in the hippocampus but not in the cortex. These findings suggest that experimental manipulation of SWS could offer useful clues into the mechanisms and treatment of AD.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Modelos Animais de Doenças , Camundongos Transgênicos , Polissonografia , Sono de Ondas Lentas , Animais , Doença de Alzheimer/fisiopatologia , Camundongos , Peptídeos beta-Amiloides/metabolismo , Sono de Ondas Lentas/fisiologia , Feminino , Temperatura , Eletroencefalografia , Encéfalo/fisiopatologia , Encéfalo/metabolismo
8.
J Alzheimers Dis ; 100(s1): S291-S304, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39121129

RESUMO

Background: Exposure to lead (Pb) is a major public health problem that could occur through contaminated soil, air, food, or water, either during the course of everyday life, or while working in hazardous occupations. Although Pb has long been known as a neurodevelopmental toxicant in children, a recent and growing body of epidemiological research indicates that cumulative, low-level Pb exposure likely drives age-related neurologic dysfunction in adults. Environmental Pb exposure in adulthood has been linked to risk of late-onset Alzheimer's disease (AD) and dementia. Objective: Although the biological mechanism underlying this link is unknown, it has been proposed that Pb exposure may increase the risk of AD via altering the expression of AD-related genes and, possibly, by activating the molecular pathways underlying AD-related pathology. Methods: We investigated Pb exposure using a line of genetically modified mice with AD-causing knock-in mutations in the amyloid precursor protein and presenilin 1 (APPΔNL/ΔNL x PS1P264L/P264L) that had been crossed with Leprdb/db mice to impart vulnerability to vascular pathology. Results: Our data show that although Pb exposure in adult mice impairs cognitive function, this effect is not related to either an increase in amyloid pathology or to changes in the expression of common AD-related genes. Pb exposure also caused a significant increase in blood pressure, a well known effect of Pb. Interestingly, although the increase in blood pressure was unrelated to genotype, only mice that carried AD-related mutations developed cognitive dysfunction, in spite of showing no significant change in cerebrovascular pathology. Conclusions: These results raise the possibility that the increased risk of dementia associated with Pb exposure in adults may be tied to its subsequent interaction with either pre-existing or developing AD-related neuropathology.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Água Potável , Chumbo , Camundongos Transgênicos , Presenilina-1 , Animais , Chumbo/toxicidade , Chumbo/sangue , Chumbo/efeitos adversos , Camundongos , Doença de Alzheimer/genética , Doença de Alzheimer/induzido quimicamente , Precursor de Proteína beta-Amiloide/genética , Presenilina-1/genética , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/genética , Masculino , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos C57BL
9.
J Rare Dis (Berlin) ; 3(1): 24, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39165678

RESUMO

Background: Tuberous sclerosis complex (TSC) is a rare approximate 1:6000 birth incidence, a genetic disease with a wide variability of physical and neuropsychiatric symptoms. Patients require lifelong care from multiple healthcare specialities, for which International and United Kingdom (UK) TSC consensus recommendations exist. Personalised care delivered by a centralised coordinated team of TSC experts is recommended. There is no such service for the estimated 600 TSC patients in the Republic of Ireland (ROI) and there is a paucity of information regarding the healthcare of this group. Purpose: Evaluate the baseline care of patients with TSC attending epilepsy services in the Republic of Ireland (ROI) against UK TSC consensus recommendations. Methods: Patients with a diagnosis of TSC attending 12 adult and paediatric epilepsy centres in the ROI were identified. Clinical audits measured the baseline care of a subset of these patients against UK, TSC clinical recommendations. Data was anonymised and analysed at Trinity College Dublin. Results: One hundred thirty-five TSC patients attending twelve epilepsy centres were identified. Adults (n = 67) paediatric (n = 68). The care of 83 patients was audited (n = 63 ≥ 18 years) and (n = 20 < 18 years). Many baseline tests were completed, however, they required intra or interhospital referral. Care appears fragmented and there was no evidence of formal disease surveillance plans. Conclusions: The number of TSC patients attending epilepsy services is lower than expected (n = 135). Specialist services and treatments for TSC are available through informal referral pathways. Although UK, TSC consensus baseline recommendations are roughly adhered to, care is fragmented. Increased coordination of care could benefit disease management. Supplementary Information: The online version contains supplementary material available at 10.1007/s44162-024-00049-8.

10.
bioRxiv ; 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38260262

RESUMO

Sustained smouldering, or low grade, activation of myeloid cells is a common hallmark of several chronic neurological diseases, including multiple sclerosis (MS) 1 . Distinct metabolic and mitochondrial features guide the activation and the diverse functional states of myeloid cells 2 . However, how these metabolic features act to perpetuate neuroinflammation is currently unknown. Using a multiomics approach, we identified a new molecular signature that perpetuates the activation of myeloid cells through mitochondrial complex II (CII) and I (CI) activity driving reverse electron transport (RET) and the production of reactive oxygen species (ROS). Blocking RET in pro-inflammatory myeloid cells protected the central nervous system (CNS) against neurotoxic damage and improved functional outcomes in animal disease models in vivo . Our data show that RET in myeloid cells is a potential new therapeutic target to foster neuroprotection in smouldering inflammatory CNS disorders 3 .

11.
J Orthop Trauma ; 38(1): 49-55, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37559208

RESUMO

OBJECTIVE: To identify technical factors associated with nonunion after operative treatment with lateral locked plating. DESIGN: Retrospective cohort study. SETTING: Ten Level I trauma centers. PATIENT SELECTION CRITERIA: Adult patients with supracondylar distal femur fractures (OTA/AO type 33A or C) treated with lateral locked plating from 2010 through 2019. OUTCOME MEASURES AND COMPARISONS: Surgery for nonunion stratified by risk for nonunion. RESULTS: The cohort included 615 patients with supracondylar distal femur fractures. The median patient age was 61 years old (interquartile range: 46 -72years) and 375 (61%) were female. Observed were nonunion rates of 2% in a low risk of nonunion group (n = 129), 4% in a medium-risk group (n = 333), and 14% in a high-risk group (n = 153). Varus malreduction with an anatomic lateral distal femoral angle greater than 84 degrees, was associated with double the odds of nonunion compared to those without such varus [odds ratio, 2.1; 95% confidence interval (CI), 1.1-4.2; P = 0.03]. Malreduction by medial translation of the articular block increased the odds of nonunion, with 30% increased odds per 4 mm of medial translation (95% CI, 1.0-1.6; P = 0.03). Working length increased the odds of nonunion in the medium risk group, with an 18% increase in nonunion per 10-mm increase in working length (95% CI, 1.0-1.4; P = 0.01). Increased proximal screw density was protective against nonunion (odds ratio, 0.71; 95% CI, 0.53-0.92; P = 0.02) but yielded lower mRUST scores with each 0.1 increase in screw density associated with a 0.4-point lower mRUST (95% CI, -0.55 to -0.15; P < 0.001). Lateral plate length and type of plate material were not associated with nonunion. ( P > 0.05). CONCLUSIONS: Malreduction is a surgeon-controlled variable associated with nonunion after lateral locked plating of supracondylar distal femur fractures. Longer working lengths were associated with nonunion, suggesting that bridge plating may be less likely to succeed for longer fractures. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Fraturas Femorais Distais , Fraturas do Fêmur , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Fraturas do Fêmur/cirurgia , Fraturas do Fêmur/etiologia , Fatores de Risco , Fixação Interna de Fraturas/efeitos adversos , Placas Ósseas/efeitos adversos , Fêmur
12.
Niger Med J ; 64(1): 4-12, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38887434

RESUMO

Monkeypox/Mpox is an Orthopoxvirus infection of the skin and mucous membranes in the same family as smallpox virus. Infection mainly affects the skin, but the eyes, lungs, brain, gastrointestinal tract, and other organs may also be involved to varying degrees. This narrative review on the systematic and dermatologic impact of Mpox is meant for healthcare workers, providers of social services, community leaders, religious leaders, staff of schools, influencers, and institutions. This is in a bid to bring them up to date with the clinical protocol involved in the diagnosis, management, and prevention of the spread of Mpox. Data and other pieces of information used in this review were accessed from PubMed, Google Scholar, and situation reports from the website of the Nigerian Centre for Disease Control (NCDC), the World Health Organization (WHO), and the Centre for Disease Control and Prevention (CDC). The search date was from 1980 to May 2022. Prompt recognition and diagnosis were found to be predicated on a high index of clinical suspicion while diagnosis can be confirmed through viral DNA polymerase chain reaction tests. The management of Mpox involves a multidisciplinary approach with Dermatologists playing a central role alongside other specialists and experts as it affects diagnosis, management, and follow-up. The Government should provide an enabling environment for surveillance, notification, and research of this global infection. Since the clinical presentation of Mpox is regularly changing, a regular review of the available guidelines is recommended.

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