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Millisecond-scale temporal spiking patterns encode sensory information in the periphery, but their role in the neocortex remains controversial. The sense of touch provides a window into temporal coding because tactile neurons often exhibit precise, repeatable, and informative temporal spiking patterns. In the somatosensory cortex (S1), responses to skin vibrations exhibit phase locking that faithfully carries information about vibratory frequency. However, the respective roles of spike timing and rate in frequency coding are confounded because vibratory frequency shapes both the timing and rates of responses. To disentangle the contributions of these two neural features, we measured S1 responses as rhesus macaques performed frequency discrimination tasks in which differences in frequency were accompanied by orthogonal variations in amplitude. We assessed the degree to which the strength and timing of responses could account for animal performance. First, we showed that animals can discriminate frequency, but their performance is biased by amplitude variations. Second, rate-based representations of frequency are susceptible to changes in amplitude but in ways that are inconsistent with the animals' behavioral biases, calling into question a rate-based neural code for frequency. In contrast, timing-based representations are highly informative about frequency but impervious to changes in amplitude, which is also inconsistent with the animals' behavior. We account for the animals' behavior with a model wherein frequency coding relies on a temporal code, but frequency judgments are biased by perceived magnitude. We conclude that information about vibratory frequency is not encoded in S1 firing rates but primarily in temporal patterning on millisecond timescales.
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Macaca mulatta , Córtex Somatossensorial , Vibração , Animais , Córtex Somatossensorial/fisiologia , Masculino , Potenciais de Ação/fisiologia , Fatores de Tempo , Estimulação Física , Tato/fisiologia , Discriminação Psicológica/fisiologia , Percepção do Tato/fisiologia , Neurônios/fisiologia , Tempo de Reação/fisiologia , FemininoRESUMO
Humans and other animals readily transition from externally to internally focused attention, and these transitions are accompanied by activation of the default mode network (DMN). The DMN was considered a cortical network, yet recent evidence suggests subcortical structures are also involved. We investigated the role of ventral pallidum (VP) and mediodorsal thalamus (MD) in DMN regulation in tree shrew, a close relative of primates. Electrophysiology and deep learning-based classification of behavioral states revealed gamma oscillations in VP and MD coordinated with gamma in anterior cingulate (AC) cortex during DMN states. Cross-frequency coupling between gamma and delta oscillations was higher during DMN than other behaviors, underscoring the engagement of MD, VP and AC. Our findings highlight the importance of VP and MD in DMN regulation, extend homologies in DMN regulation among mammals, and underline the importance of thalamus and basal forebrain to the regulation of DMN.
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Prosencéfalo Basal , Rede de Modo Padrão , Animais , Rede de Modo Padrão/fisiologia , Prosencéfalo Basal/fisiologia , Tupaiidae/fisiologia , Masculino , Tálamo/fisiologia , Giro do Cíngulo/fisiologia , Feminino , Núcleo Mediodorsal do Tálamo/fisiologiaRESUMO
BACKGROUND: The Veterans Health Administration (VA) implemented academic detailing (AD) to support safer opioid prescribing and overdose prevention initiatives. METHODS: Patient-level data were extracted monthly from VA's electronic health record to evaluate whether AD implementation was associated with changes in all-cause mortality, opioid poisoning inpatient admissions, and opioid poisoning emergency department (ED) visits in an observational cohort of patients with long-term opioid prescriptions (≥45-day supply of opioids 6 months prior to a given month with ≤15 days between prescriptions). A single-group interrupted time series analysis using segmented logistic regression for mortality and Poisson regression for counts of inpatient admissions and ED visits was used to identify whether the level and slope of these outcomes changed in response to AD implementation. RESULTS: Among 955 376 unique patients (19 431 241 person-months), there were 53 369 deaths (29 025 pre-AD; 24 344 post-AD), 1927 opioid poisoning inpatient admissions (610 pre-AD; 1317 post-AD), and 408 opioid poisoning ED visits (207 pre-AD; 201 post-AD). Immediately after AD implementation, there was a 5.8% reduction in the odds of all-cause mortality (95% confidence interval [CI]: 0.897, 0.990). However, patients had a significantly increased incidence rate of inpatient admissions for opioid poisoning immediately after AD implementation (incidence rate ratio = 1.523; 95% CI: 1.118, 2.077). No significant differences in ED visits for opioid poisoning were observed. CONCLUSIONS: AD was associated with decreased all-cause mortality but increased inpatient hospitalization for opioid poisoning among patients prescribed long-term opioids. Mechanisms via which AD's efforts influenced opioid-related outcomes should be explored.
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Analgésicos Opioides , Serviço Hospitalar de Emergência , United States Department of Veterans Affairs , Humanos , Analgésicos Opioides/efeitos adversos , Analgésicos Opioides/intoxicação , Analgésicos Opioides/uso terapêutico , Estados Unidos/epidemiologia , Masculino , Feminino , United States Department of Veterans Affairs/estatística & dados numéricos , Pessoa de Meia-Idade , Adulto , Serviço Hospitalar de Emergência/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Overdose de Opiáceos/mortalidade , Overdose de Opiáceos/epidemiologia , Idoso , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Transtornos Relacionados ao Uso de Opioides/mortalidade , Análise de Séries Temporais Interrompida , Registros Eletrônicos de Saúde/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricosRESUMO
Periprosthetic joint infection (PJI) following revision total knee arthroplasty (TKA) for aseptic failure is associated with poor outcomes, patient morbidity, and high health care expenditures. The aim of this study was to develop novel machine learning algorithms for the prediction of PJI following revision TKA for patients with aseptic indications for revision surgery. A single-institution database consisting of 1,432 consecutive revision TKA patients with aseptic etiologies was retrospectively identified. The patient cohort included 208 patients (14.5%) who underwent re-revision surgery for PJI. Three machine learning algorithms (artificial neural networks, support vector machines, k-nearest neighbors) were developed to predict this outcome and these models were assessed by discrimination, calibration, and decision curve analysis. This is a retrospective study. Among the three machine learning models, the neural network model achieved the best performance across discrimination (area under the receiver operating characteristic curve = 0.78), calibration, and decision curve analysis. The strongest predictors for PJI following revision TKA for aseptic reasons were prior open procedure prior to revision surgery, drug abuse, obesity, and diabetes. This study utilized machine learning as a tool for the prediction of PJI following revision TKA for aseptic failure with excellent performance. The validated machine learning models can aid surgeons in patient-specific risk stratifying to assist in preoperative counseling and clinical decision making for patients undergoing aseptic revision TKA.
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Artrite Infecciosa , Artroplastia do Joelho , Infecções Relacionadas à Prótese , Humanos , Artroplastia do Joelho/efeitos adversos , Estudos Retrospectivos , Inteligência Artificial , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/cirurgia , Artrite Infecciosa/cirurgia , Reoperação/efeitos adversosRESUMO
AIMS: To evaluate the clinical safety, tolerability, and pharmacokinetic and pharmacodynamic profile of the novel cannabinoid receptor-1 (CB1R) inverse agonist, INV-202, in adults with features of metabolic syndrome. MATERIALS AND METHODS: This was a multicentre, randomized, double-blind, placebo-controlled, 28-day repeat-dose (INV-202 [25 mg] or placebo, once-daily oral tablet), parallel-group study in 37 participants aged 18 to 65 years (46% female, mean age 55 years, glycated haemoglobin 5.7% [39 mmol/mol], body mass index [BMI] 38.1 kg/m2 ) with features of metabolic syndrome and glucose intolerance. An oral glucose tolerance test (OGTT) was performed at baseline and at the end of the study. Lipid profiles, weight, waist circumference and biomarkers were assessed weekly. Statistical comparisons were performed post hoc. RESULTS: INV-202 was well tolerated with no serious or severe treatment-emergent adverse events; the most common events related to known effects of CB1R blockade in the gastrointestinal tract. INV-202 produced a significant mean weight loss of 3.5 kg (3.3% compared with placebo participants who gained a mean 0.6 kg [0.5%]). INV-202 also exhibited significant reductions in waist circumference and BMI (P ≤ 0.03). There was no significant difference in OGTT 0- to 3-hour area under the curve for INV-202 versus placebo: least squares mean 29.38 versus 30.25 h*mmol/L, with an INV-202: placebo ratio of 97.1% (95% confidence interval 90.2, 105.6; P = 0.43). CONCLUSIONS: INV-202 was well tolerated, producing a signal for rapid weight loss with improvements in other metabolic syndrome markers in this population. These findings support further exploration and long-term assessment of cardiometabolic effects.
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Diabetes Mellitus Tipo 2 , Síndrome Metabólica , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Síndrome Metabólica/tratamento farmacológico , Agonismo Inverso de Drogas , Hemoglobinas Glicadas , Teste de Tolerância a Glucose , Método Duplo-Cego , Redução de Peso , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Resultado do TratamentoRESUMO
BACKGROUND AND OBJECTIVES: Piflufolastat F 18 is a novel prostate-specific membrane antigen (PSMA)-targeted positron emission tomography (PET) radiotracer that is superior to standard of care (SOC) imaging for the initial staging of prostate cancer and the detection of biochemical recurrence. As piflufolastat F 18 has been approved in the United States (US) for this indication, this modeling study assessed the cost effectiveness of piflufolastat F 18 versus fluciclovine F-18, gallium68-PSMA-11 (PSMA 11), and SOC imaging (a mix of bone scans, computed tomography, and magnetic resonance imaging) for the diagnosis and staging of prostate cancer from a US healthcare system perspective. PERSPECTIVE: A US third-party payer perspective was used, which for this population reflects a mix of commercial and Medicare, considering only direct healthcare costs. SETTING: This study utilized a tertiary healthcare setting. METHODS: A decision tree was used to map the diagnostic/treatment pathway, consisting of the proportion of patients with local, regional, distant, or no disease; prostate-specific antigen (PSA) ≤ 1.0 or > 1.0; and accuracy of imaging modalities. A Markov model predicted the long-term outcomes of disease progression according to treatment decisions. Inputs to the model were informed by data from the OSPREY and CONDOR clinical trials, public data, and the literature. Treatment mix included active surveillance, radiation therapy, prostatectomy, androgen deprivation therapy (ADT), and radiation therapy + ADT, informed by expert opinion. Outcomes included life-years (LY), quality-adjusted life-years (QALY), and the incremental cost-effectiveness ratio (ICER). All costs were reported in 2021 US dollars, using the US Bureau of Labor Statistics Consumer Price Index. A willingness-to-pay (WTP) threshold of $150,000 was considered cost effective, consistent with the upper range used as the standard for price benchmarks by the Institute for Clinical and Economic Review. The robustness of the base-case results was assessed in deterministic and probabilistic sensitivity analyses. RESULTS: Over a lifetime horizon, piflufolastat F 18 had the greatest effectiveness in terms of LYs (6.80) and QALYs (5.33); for the comparators, LYs ranged from 6.58 (SOC) to 6.76 (PSMA 11) and QALYs ranged from 5.12 (SOC) and 5.30 (PSMA 11). Piflufolastat F 18 was more cost effective compared with fluciclovine F 18, PSMA 11, and SOC, with ICERs of $21,122, $55,836, and $124,330 per QALY gained, respectively. Piflufolastat F 18 was associated with the greatest net monetary benefit ($627,918) compared with the other options at a WTP threshold of $150,000. The results of the deterministic and probabilistic sensitivity analyses supported the robustness of the base-case results. CONCLUSIONS: This study suggests that piflufolastat F 18 is a cost-effective diagnostic option for men with prostate cancer in the US, with higher associated LY, QALY, and greater net monetary benefit than fluciclovine F 18, PSMA 11, and SOC imaging.
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Ácidos Carboxílicos , Ciclobutanos , Radioisótopos de Gálio , Neoplasias da Próstata , Masculino , Humanos , Idoso , Estados Unidos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Análise Custo-Benefício , Análise de Custo-Efetividade , Próstata/patologia , Antagonistas de Androgênios , Medicare , Tomografia por Emissão de Pósitrons , Anos de Vida Ajustados por Qualidade de VidaRESUMO
Biodiversity loss is a major global challenge and minimizing extinction rates is the goal of several multilateral environmental agreements. Policy decisions require comprehensive, spatially explicit information on species' distributions and threats. We present an analysis of the conservation status of 14,669 European terrestrial, freshwater and marine species (ca. 10% of the continental fauna and flora), including all vertebrates and selected groups of invertebrates and plants. Our results reveal that 19% of European species are threatened with extinction, with higher extinction risks for plants (27%) and invertebrates (24%) compared to vertebrates (18%). These numbers exceed recent IPBES (Intergovernmental Platform on Biodiversity and Ecosystem Services) assumptions of extinction risk. Changes in agricultural practices and associated habitat loss, overharvesting, pollution and development are major threats to biodiversity. Maintaining and restoring sustainable land and water use practices is crucial to minimize future biodiversity declines.
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Conservação dos Recursos Naturais , Ecossistema , Animais , Biodiversidade , Vertebrados , Invertebrados , Plantas , Extinção Biológica , Espécies em Perigo de ExtinçãoRESUMO
Introduction: Changing population demographics and the recent SARS-CoV-2 pandemic have forever changed healthcare, with increasing demands on straining systems. The economic cost is yet to be fully realised, with growing concerns around the current system's ability to accommodate the ageing comorbid population. Consequently, a paradigm shift has taken place in healthcare systems, prioritizing cost accountability. In the absence of established guidelines or robust literature, the use of laboratory tests postoperatively is often guided solely by clinician preference. This study presents a retrospective analysis that investigates the utility and cost implications of routine postoperative investigation following robotic-assisted radical prostatectomies. The findings aim to emphasise the importance of evidence-based practices and cost-effective approaches in postoperative care. Materials/Methods: A retrospective analysis was performed on all robotic-assisted radical prostatectomies (RARP) identified from a single institution between 29th June 2017 to 28th June 2019. This interval was chosen in an attempt to avoid bias or confounding variables associated with the SRS-CoV-2 pandemic. A single clinician conducted a comprehensive medical record review using unit record numbers corresponding to identified procedural codes. Demographics and variables were recorded, including postoperative test results, hospital length of stay and 30-day readmission rates. Patients were assigned to either 'Routine Postoperative tests' (RPOT) or 'No Routine Postoperative tests' (No RPOT) and a comparative analysis was performed. Using the Australian National Pharmaceutical Benefits Scheme (PBS) pricing guide, total expenditure was calculated. Results: A total of 319 patients were included in the study with an average of 2.5 tests per patient within the first 24 hours. Routine postoperative tests had no bearing on outcomes, with comparable readmission rates between cohorts, and a significantly shorter length of stay in the "No routine postoperative tests" group when compared to the "Routine Postoperative Tests". A total of 1028 tests were performed within the first 48 hours following surgery with expenditure on routine testing totalling $20,516 based on the Australian PBS pricing schedule. Abnormal results were returned on 96% of patients. In the RPOT group, 18 out of the 20 common interventions occurred from 302 RARP. Among the patients in the RPOT group, eight individuals underwent blood transfusions. However, none of these patients met the hospital-specific criteria for transfusion, which require a hemoglobin level below 70 or symptomatic presentation with a hemoglobin level below 80. Conclusion: The data suggests routine postoperative laboratory has no bearing on re-admission rates, with patients experiencing significantly shorter hospital stays. Furthermore, our results indicate inefficient use of routine postoperative laboratory, with few clinical interventions, frequent abnormal results, and significant accumulative expenses.
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The lateral geniculate nucleus (LGN), a retinotopic relay center where visual inputs from the retina are processed and relayed to the visual cortex, has been proposed as a potential target for artificial vision. At present, it is unknown whether optogenetic LGN stimulation is sufficient to elicit behaviorally relevant percepts, and the properties of LGN neural responses relevant for artificial vision have not been thoroughly characterized. Here, we demonstrate that tree shrews pretrained on a visual detection task can detect optogenetic LGN activation using an AAV2-CamKIIα-ChR2 construct and readily generalize from visual to optogenetic detection. Simultaneous recordings of LGN spiking activity and primary visual cortex (V1) local field potentials (LFPs) during optogenetic LGN stimulation show that LGN neurons reliably follow optogenetic stimulation at frequencies up to 60 Hz and uncovered a striking phase locking between the V1 LFP and the evoked spiking activity in LGN. These phase relationships were maintained over a broad range of LGN stimulation frequencies, up to 80 Hz, with spike field coherence values favoring higher frequencies, indicating the ability to relay temporally precise information to V1 using light activation of the LGN. Finally, V1 LFP responses showed sensitivity values to LGN optogenetic activation that were similar to the animal's behavioral performance. Taken together, our findings confirm the LGN as a potential target for visual prosthetics in a highly visual mammal closely related to primates.
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Optogenética , Tálamo , Animais , Tálamo/fisiologia , Corpos Geniculados/fisiologia , Visão Ocular , Neurônios/fisiologia , Estimulação Luminosa , Vias Visuais/fisiologia , MamíferosRESUMO
During chronic schistosome infections, a complex regulatory network is induced to regulate the host immune system, in which IL-10-producing regulatory B (Breg) cells play a significant role. Schistosoma mansoni soluble egg antigens (SEA) are bound and internalized by B cells and induce both human and mouse IL-10 producing Breg cells. To identify Breg-inducing proteins in SEA, we fractionated SEA by size exclusion chromatography and found 6 fractions able to induce IL-10 production by B cells (out of 18) in the high, medium and low molecular weight (MW) range. The high MW fractions were rich in heavily glycosylated molecules, including multi-fucosylated proteins. Using SEA glycoproteins purified by affinity chromatography and synthetic glycans coupled to gold nanoparticles, we investigated the role of these glycan structures in inducing IL-10 production by B cells. Then, we performed proteomics analysis on active low MW fractions and identified a number of proteins with putative immunomodulatory properties, notably thioredoxin (SmTrx1) and the fatty acid binding protein Sm14. Subsequent splenic murine B cell stimulations and hock immunizations with recombinant SmTrx1 and Sm14 showed their ability to dose-dependently induce IL-10 production by B cells both in vitro and in vivo. Identification of unique Breg cells-inducing molecules may pave the way to innovative therapeutic strategies for inflammatory and auto-immune diseases.
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Linfócitos B Reguladores , Nanopartículas Metálicas , Esquistossomose mansoni , Humanos , Animais , Camundongos , Schistosoma mansoni , Esquistossomose mansoni/prevenção & controle , Interleucina-10/genética , Ouro , Fatores Imunológicos , Tiorredoxinas/genética , Antígenos de HelmintosRESUMO
The acanthocephalan Macracanthorhynchus ingens (von Linstow 1879) (Acanthocephala: Archiacanthocephala) is a parasite that infects the gut of carnivores (racoons, coyotes, wolves, foxes, badgers, skunks, opossum, mink and bears) as an adult and the body cavity of lizards, snakes, and frogs as a cystacanth in the Americas. In this study, adults and cystacanths of M. ingens from southeastern Mexico and southern Florida, USA, were identified morphologically by having a cylindrical proboscis armed with 6 rows of hooks each with 6 hooks. Hologenophores were used to sequence the small (SSU) and large (LSU) subunits of ribosomal DNA and cytochrome c oxidase subunit 1 (cox 1) from mitochondrial DNA. Phylogenetic analysis of the new SSU and LSU sequences of M. ingens placed them in a clade with other sequences available in GenBank identified as M. ingens. The cox 1 tree showed that the nine new sequences and six previously published sequences of M. ingens from the USA form a clade with other sequences previously identified as M. ingens from GenBank. The intraspecific genetic divergence among isolates from the Americas ranged from 0 to 2%, and in combination with the phylogenetic trees confirmed that the isolates belonged to the same species. The cox 1 haplotype network inferred with 15 sequences revealed 10 haplotypes separated from each other by a few substitutions. Rio Grande Leopard Frogs and Vaillant´s Frogs harbored cystacanths with low prevalence, 28% and 37% respectively, in Mexico. Brown Basilisks, an invasive lizard in Florida, USA, had high values of prevalence, 92% and 93% in males and females, respectively. Females harbored more cystacanths than males (0-39 vs 0-21) for unknown reasons that may, however, be related to ecological differences.
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Acantocéfalos , Helmintíase Animal , Feminino , Masculino , Animais , México , Filogenia , Helmintíase Animal/epidemiologia , Helmintíase Animal/parasitologia , Especificidade da EspécieRESUMO
ABSTRACTStructural competency is a recent framework for understanding and addressing the structural drivers of disease. Latin American Social Medicine and Collective Health is a decades-long movement similarly concerned with the study and transformation of social structures to achieve health equity. In this paper, we put insights from Latin American Social Medicine and Collective Health into conversation with the developing structural competency framework. We focus specifically on insights from Jaime Breilh's new article summarising his theoretical work on medical ethics and rights in this special issue and his new book, Critical Epidemiology and the People's Health. This paper is comprised of three parts. Part 1 provides an introduction to the structural competency framework. Part 2 provides an overview of the Latin American Social Medicine and Collective Health movement, along with a summary of the social determination of health paradigm. Part 3 places insights from these works into conversation with structural competency and considers ways in which Latin American Social Medicine and Collective Health might inform the further development of structural competency, and potentially vice versa. The paper closes by calling for greater attention to Latin American Social Medicine and Collective Health among those committed to health equity within the anglophone world.
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Medicina Social , Humanos , América LatinaRESUMO
Understanding the factors that govern variation in genetic structure across species is key to the study of speciation and population genetics. Genetic structure has been linked to several aspects of life history, such as foraging strategy, habitat association, migration distance, and dispersal ability, all of which might influence dispersal and gene flow. Comparative studies of population genetic data from species with differing life histories provide opportunities to tease apart the role of dispersal in shaping gene flow and population genetic structure. Here, we examine population genetic data from sets of bird species specialized on a series of Amazonian habitat types hypothesized to filter for species with dramatically different dispersal abilities: stable upland forest, dynamic floodplain forest, and highly dynamic riverine islands. Using genome-wide markers, we show that habitat type has a significant effect on population genetic structure, with species in upland forest, floodplain forest, and riverine islands exhibiting progressively lower levels of structure. Although morphological traits used as proxies for individual-level dispersal ability did not explain this pattern, population genetic measures of gene flow are elevated in species from more dynamic riverine habitats. Our results suggest that the habitat in which a species occurs drives the degree of population genetic structuring via its impact on long-term fluctuations in levels of gene flow, with species in highly dynamic habitats having particularly elevated gene flow. These differences in genetic variation across taxa specialized in distinct habitats may lead to disparate responses to environmental change or habitat-specific diversification dynamics over evolutionary time scales.
A compreensão dos fatores que governam a variação da estrutura genética entre as espécies é fundamental para o estudo da especiação e da genética das populações. A estrutura genética tem sido ligada a vários aspectos da história da vida, tais como estratégia de forrageio, associação ao habitat, distância de migração e capacidade de dispersão, os quais poderiam influenciar a dispersão e o fluxo gênico. Estudos comparativos usando espécies que diferem nas suas histórias de vida oferecem uma oportunidade para desvendar o papel da dispersão no estabelecimento do fluxo gênico e da estrutura genética da população. Aqui examinamos dados genéticos populacionais de diversas espécies de aves com diferentes capacidades de dispersão especializadas em três habitats amazônicos, incluindo florestas de terra-firme, florestas de várzea e ilhas fluviais, cujos ambientes ripários são altamente dinâmicos. Utilizando dados genômicos que incluem milhares de loci, mostramos que o tipo de habitat tem um efeito significativo na estruturação genética das populações; espécies de florestas de terra-firme, florestas de várzea e ilhas fluviais exibem níveis de estruturação progressivamente menores. Embora os traços morfológicos frequentemente usados como indicadores da capacidade de dispersão a nível individual não expliquem este padrão, as medidas genéticas populacionais de fluxo gênico são altas em espécies associadas a habitats ribeirinhos mais dinâmicos. Nossos resultados sugerem que o habitat no qual uma espécie é encontrada determina o grau de estruturação genética da população através de seu impacto nas flutuações de longo prazo do fluxo gênico, com espécies em habitats altamente dinâmicos tendo um fluxo gênico particularmente alto. As diferenças na variação genética dos táxons especializados em diferentes habitats podem resultar em respostas díspares às mesmas mudanças ambientais, ou dinâmicas de diversificação específicas a um determinado habitat ao longo de escalas de tempo evolutivas.
Comprender los factores que rigen la variación de la estructura genética entre especies es clave para el estudio de la especiación y la genética de poblaciones. La estructura genética se ha relacionado con varios aspectos de la historia vital, como la estrategia de búsqueda de alimento, la asociación de hábitats, la distancia de migración y la capacidad de dispersión, factores todos ellos que podrían influir en la dispersión y el flujo genético. Los estudios comparativos de datos genéticos poblacionales de especies con historias vitales diferentes ofrecen la oportunidad de desentrañar el papel de la dispersión en la conformación del flujo genético y la estructura genética poblacional. En este trabajo examinamos los datos genéticos de poblaciones de especies de aves especializadas en una serie de hábitats amazónicos que, según la hipótesis, filtran especies con capacidades de dispersión radicalmente diferentes: bosques estables de tierras altas, bosques dinámicos de llanuras aluviales e islas fluviales altamente dinámicas. Utilizando marcadores genómicos, demostramos que el tipo de hábitat tiene un efecto significativo en la estructura genética de la población, y que las especies de los bosques de tierras altas, los bosques inundables y las islas fluviales presentan niveles de estructura progresivamente más bajos. Aunque los rasgos morfológicos utilizados como indicadores de la capacidad de dispersión individual no explican este patrón, las medidas genéticas poblacionales del flujo genético son más elevadas en las especies de hábitats fluviales más dinámicos. Nuestros resultados sugieren que el hábitat en el que se encuentra una especie determina el grado de estructuración genética de la población a través de su impacto en las fluctuaciones a largo plazo de los niveles de flujo genético, siendo las especies de hábitats muy dinámicos las que presentan un flujo genético particularmente elevado. Estas diferencias en la variación genética entre taxones especializados en hábitats distintos pueden dar lugar a respuestas dispares al cambio ambiental o a dinámicas de diversificación específicas del hbitat a lo largo de escalas temporales evolutivas.
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Ecossistema , Fluxo Gênico , Animais , Florestas , Aves/genética , Genética Populacional , Variação GenéticaRESUMO
OBJECTIVES: To provide a comprehensive narrative review of the published data on the impact of hydrogel spacers on rectal dosimetry and toxicity and to outline the practicalities of inserting hydrogel spacers. RESULTS: A growing body of evidence suggests that the administration of hydrogel spacers is safe and is associated with limited peri-operative morbidity. The impact on rectal dosimetry has been clearly established and use of hydrogel spacers is associated with reduced rectal morbidity. These results have been corroborated by several Phase II and III clinical trials and subsequent meta-analysis. There are several areas for future research, including the role of hydrogel spacers in prostate stereotactic beam radiotherapy and post-radiotherapy local recurrence. CONCLUSIONS: Hydrogel spacers provide a low-morbidity method to potential reduce rectal toxicity after radiation therapy in men with prostate cancer. Data outlining sexual function and oncological outcomes are limited to date. Future studies, currently being conducted, may provide further clarification of the role of hydrogel spacers in prostate cancer management.
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Hidrogéis , Neoplasias da Próstata , Humanos , Masculino , Próstata , Neoplasias da Próstata/cirurgia , Radiometria , Dosagem Radioterapêutica , RetoRESUMO
BACKGROUND: Patient-reported outcome measures (PROMs) are increasingly used as quality benchmark in total hip and knee arthroplasty (THA; TKA) due to bundled payment systems that aim to provide a patient-centered, value-based treatment approach. However, there is a paucity of predictive tools for postoperative PROMs. Therefore, this study aimed to develop and validate machine learning models for the prediction of numerous patient-reported outcome measures following primary hip and knee total joint arthroplasty. METHODS: A total of 4526 consecutive patients (2137 THA; 2389 TKA) who underwent primary hip and knee total joint arthroplasty and completed both pre- and postoperative PROM scores was evaluated in this study. The following PROM scores were included for analysis: HOOS-PS, KOOS-PS, Physical Function SF10A, PROMIS SF Physical and PROMIS SF Mental. Patient charts were manually reviewed to identify patient demographics and surgical variables associated with postoperative PROM scores. Four machine learning algorithms were developed to predict postoperative PROMs following hip and knee total joint arthroplasty. Model assessment was performed through discrimination, calibration and decision curve analysis. RESULTS: The factors most significantly associated with the prediction of postoperative PROMs include preoperative PROM scores, Charlson Comorbidity Index, American Society of Anaesthesiology score, insurance status, age, length of hospital stay, body mass index and ethnicity. The four machine learning models all achieved excellent performance across discrimination (AUC > 0.83), calibration and decision curve analysis. CONCLUSION: This study developed machine learning models for the prediction of patient-reported outcome measures at 1-year following primary hip and knee total joint arthroplasty. The study findings show excellent performance on discrimination, calibration and decision curve analysis for all four machine learning models, highlighting the potential of these models in clinical practice to inform patients prior to surgery regarding their expectations of postoperative functional outcomes following primary hip and knee total joint arthroplasty. LEVEL OF EVIDENCE: Level III, case control retrospective analysis.
Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Humanos , Estudos Retrospectivos , Aprendizado de Máquina , Algoritmos , Medidas de Resultados Relatados pelo Paciente , Resultado do TratamentoRESUMO
The hydrolysis of xenobiotic glucuronides by gut bacterial glucuronidases reactivates previously detoxified compounds resulting in severe gut toxicity for the host. Selective bacterial ß-glucuronidase inhibitors can mitigate this toxicity but their impact on wider host metabolic processes has not been studied. To investigate this the inhibitor 4-(8-(piperazin-1-yl)-1,2,3,4-tetrahydro-[1,2,3]triazino[4',5':4,5]thieno[2,3-c]isoquinolin-5-yl)morpholine (UNC10201652, Inh 9) was administered to mice to selectively inhibit a narrow range of bacterial ß-glucuronidases in the gut. The metabolomic profiles of the intestinal contents, biofluids, and several tissues involved in the enterohepatic circulation were measured and compared to control animals. No biochemical perturbations were observed in the plasma, liver or gall bladder. In contrast, the metabolite profiles of urine, colon contents, feces and gut wall were altered compared to the controls. Changes were largely restricted to compounds derived from gut microbial metabolism. This work establishes that inhibitors targeted towards bacterial ß-glucuronidases modulate the functionality of the intestinal microbiota without adversely impacting the host metabolic system.
Assuntos
Microbioma Gastrointestinal , Glucuronidase , Camundongos , Animais , Glucuronidase/metabolismo , Microbioma Gastrointestinal/fisiologia , Xenobióticos , Bactérias/metabolismo , MorfolinasRESUMO
The concept of the social determinants of health has become increasingly accepted and mainstream in anglophone public health over the past three decades. Moreover, it has been widely adopted into diverse geographic, sociocultural, and linguistic contexts. By recognizing the role of social conditions in influencing health inequalities, the concept challenges narrow behavioral and reductive biological understandings of health. Despite this, scholars and activists have critiqued the concept of the social determinants of health for being incomplete and even misrepresenting the true nature of health inequities. Arguably, these critiques have been most thoroughly developed among those working in the Latin American social medicine and collective health traditions who formulated the "social determination of health" paradigm and the concept of interculturality decades prior to the advent of the social determinants of health. We draw on Jaime Breilh's main works, with a focus on the recently published book, Critical Epidemiology and the People's Health, to (1) provide a broad overview of the social determination of health paradigm and its approach to interculturality and (2) clarify how these ideas and the broader collective health movement challenge assumptions within the social determinants of health concept.