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1.
Nat Immunol ; 25(7): 1231-1244, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38898157

RESUMO

To understand the role of T cells in the pathogenesis of ulcerative colitis (UC), we analyzed colonic T cells isolated from patients with UC and controls. Here we identified colonic CD4+ and CD8+ T lymphocyte subsets with gene expression profiles resembling stem-like progenitors, previously reported in several mouse models of autoimmune disease. Stem-like T cells were increased in inflamed areas compared to non-inflamed regions from the same patients. Furthermore, TCR sequence analysis indicated stem-like T cells were clonally related to proinflammatory T cells, suggesting their involvement in sustaining effectors that drive inflammation. Using an adoptive transfer colitis model in mice, we demonstrated that CD4+ T cells deficient in either BCL-6 or TCF1, transcription factors that promote T cell stemness, had decreased colon T cells and diminished pathogenicity. Our results establish a strong association between stem-like T cell populations and UC pathogenesis, highlighting the potential of targeting this population to improve clinical outcomes.


Assuntos
Colite Ulcerativa , Fator 1-alfa Nuclear de Hepatócito , Colite Ulcerativa/imunologia , Colite Ulcerativa/patologia , Humanos , Animais , Camundongos , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Fator 1-alfa Nuclear de Hepatócito/genética , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD4-Positivos/imunologia , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6/genética , Células-Tronco/imunologia , Células-Tronco/metabolismo , Feminino , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Camundongos Knockout , Colo/imunologia , Colo/patologia , Masculino , Camundongos Endogâmicos C57BL , Transferência Adotiva , Modelos Animais de Doenças , Adulto , Pessoa de Meia-Idade
2.
Nature ; 617(7959): 61-66, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37076625

RESUMO

Experiments on disordered alloys1-3 suggest that spin glasses can be brought into low-energy states faster by annealing quantum fluctuations than by conventional thermal annealing. Owing to the importance of spin glasses as a paradigmatic computational testbed, reproducing this phenomenon in a programmable system has remained a central challenge in quantum optimization4-13. Here we achieve this goal by realizing quantum-critical spin-glass dynamics on thousands of qubits with a superconducting quantum annealer. We first demonstrate quantitative agreement between quantum annealing and time evolution of the Schrödinger equation in small spin glasses. We then measure dynamics in three-dimensional spin glasses on thousands of qubits, for which classical simulation of many-body quantum dynamics is intractable. We extract critical exponents that clearly distinguish quantum annealing from the slower stochastic dynamics of analogous Monte Carlo algorithms, providing both theoretical and experimental support for large-scale quantum simulation and a scaling advantage in energy optimization.

3.
J Mol Evol ; 92(3): 317-328, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38814340

RESUMO

Snakes in the family Elapidae largely produce venoms rich in three-finger toxins (3FTx) that bind to the α 1 subunit of nicotinic acetylcholine receptors (nAChRs), impeding ion channel activity. These neurotoxins immobilize the prey by disrupting muscle contraction. Coral snakes of the genus Micrurus are specialist predators who produce many 3FTx, making them an interesting system for examining the coevolution of these toxins and their targets in prey animals. We used a bio-layer interferometry technique to measure the binding interaction between 15 Micrurus venoms and 12 taxon-specific mimotopes designed to resemble the orthosteric binding region of the muscular nAChR subunit. We found that Micrurus venoms vary greatly in their potency on this assay and that this variation follows phylogenetic patterns rather than previously reported patterns of venom composition. The long-tailed Micrurus tend to have greater binding to nAChR orthosteric sites than their short-tailed relatives and we conclude this is the likely ancestral state. The repeated loss of this activity may be due to the evolution of 3FTx that bind to other regions of the nAChR. We also observed variations in the potency of the venoms depending on the taxon of the target mimotope. Rather than a pattern of prey-specificity, we found that mimotopes modeled after snake nAChRs are less susceptible to Micrurus venoms and that this resistance is partly due to a characteristic tryptophan → serine mutation within the orthosteric site in all snake mimotopes. This resistance may be part of a Red Queen arms race between coral snakes and their prey.


Assuntos
Cobras Corais , Venenos Elapídicos , Filogenia , Receptores Nicotínicos , Venenos Elapídicos/genética , Venenos Elapídicos/metabolismo , Venenos Elapídicos/química , Animais , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/genética , Cobras Corais/metabolismo , Cobras Corais/genética , Interferometria , Comportamento Predatório/fisiologia , Elapidae/genética , Elapidae/metabolismo
4.
PLoS Pathog ; 18(6): e1010573, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35679349

RESUMO

Powassan virus (POWV) is an emerging tick borne flavivirus (TBFV) that causes severe neuroinvasive disease. Currently, there are no approved treatments or vaccines to combat POWV infection. Here, we generated and characterized a nanoparticle immunogen displaying domain III (EDIII) of the POWV E glycoprotein. Immunization with POWV EDIII presented on nanoparticles resulted in significantly higher serum neutralizing titers against POWV than immunization with monomeric POWV EDIII. Furthermore, passive transfer of EDIII-reactive sera protected against POWV challenge in vivo. We isolated and characterized a panel of EDIII-specific monoclonal antibodies (mAbs) and identified several that potently inhibit POWV infection and engage distinct epitopes within the lateral ridge and C-C' loop of the EDIII. By creating a subunit-based nanoparticle immunogen with vaccine potential that elicits antibodies with protective activity against POWV infection, our findings enhance our understanding of the molecular determinants of antibody-mediated neutralization of TBFVs.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Nanopartículas , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , Camundongos
5.
J Urol ; 211(1): 111-123, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37796776

RESUMO

PURPOSE: Overactive bladder (OAB) may be attributed to dysfunction in supraspinal brain circuits. Overactive bladder participants enrolled in the LURN (Symptoms of Lower Urinary Tract Dysfunction Research Network) study reported sensations of urinary urgency during a bladder-filling paradigm while undergoing brain functional MRI to map supraspinal dysfunction. MATERIALS AND METHODS: OAB participants and controls (CONs) completed 2 resting-state functional MRI scans following consumption of 350 mL water. Scans were conducted at fuller and emptier bladder states, interleaved with voiding. Urgency ratings (0-10) were assessed. Patterns of urgency during bladder filling were investigated using latent class trajectory models. Clusters of participants encompassing each pattern (ie, subtype) were derived from aggregated groups of OAB and CON independent of diagnosis. RESULTS: Two distinct patterns of urgency trajectories were revealed: first subtype with OAB and CON who were unresponsive to bladder filling (OAB-1 and CON-1) and second highly responsive subtype predominantly containing OAB (OAB-2). OAB-2 participants scored significantly higher on urinary symptoms but not pain or psychosocial measures. Neuroimaging analyses showed change in urgency due to both bladder filling and voided volume related to multiple loci of brain network connectivity in OAB-2, and in some cases, different than OAB-1 and/or CON-1. Sensorimotor to dorsomedial/dorsolateral prefrontal connectivity mediated the relationship between stimulus (voided volume) and percept (urgency) in OAB-2. CONCLUSIONS: Our results reveal different OAB subtypes with latent class trajectory models of urgency ratings during natural bladder filling. Functional MRI revealed differences in pathophysiology between subtypes, namely sensorimotor-prefrontal connectivity is a key locus in OAB patients with higher urinary symptoms.


Assuntos
Sintomas do Trato Urinário Inferior , Bexiga Urinária Hiperativa , Humanos , Bexiga Urinária/diagnóstico por imagem , Micção , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética
6.
Nat Rev Neurosci ; 20(1): 34-48, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30464208

RESUMO

Emerging evidence now indicates that mitochondria are central regulators of neural stem cell (NSC) fate decisions and are crucial for both neurodevelopment and adult neurogenesis, which in turn contribute to cognitive processes in the mature brain. Inherited mutations and accumulated damage to mitochondria over the course of ageing serve as key factors underlying cognitive defects in neurodevelopmental disorders and neurodegenerative diseases, respectively. In this Review, we explore the recent findings that implicate mitochondria as crucial regulators of NSC function and cognition. In this respect, mitochondria may serve as targets for stem-cell-based therapies and interventions for cognitive defects.


Assuntos
Encéfalo/metabolismo , Diferenciação Celular/fisiologia , Cognição/fisiologia , Mitocôndrias/metabolismo , Células-Tronco Neurais/metabolismo , Animais , Encéfalo/citologia , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/patologia , Humanos , Células-Tronco Neurais/citologia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Neurogênese/fisiologia
7.
Nature ; 560(7719): 456-460, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30135527

RESUMO

The work of Berezinskii, Kosterlitz and Thouless in the 1970s1,2 revealed exotic phases of matter governed by the topological properties of low-dimensional materials such as thin films of superfluids and superconductors. A hallmark of this phenomenon is the appearance and interaction of vortices and antivortices in an angular degree of freedom-typified by the classical XY model-owing to thermal fluctuations. In the two-dimensional Ising model this angular degree of freedom is absent in the classical case, but with the addition of a transverse field it can emerge from the interplay between frustration and quantum fluctuations. Consequently, a Kosterlitz-Thouless phase transition has been predicted in the quantum system-the two-dimensional transverse-field Ising model-by theory and simulation3-5. Here we demonstrate a large-scale quantum simulation of this phenomenon in a network of 1,800 in situ programmable superconducting niobium flux qubits whose pairwise couplings are arranged in a fully frustrated square-octagonal lattice. Essential to the critical behaviour, we observe the emergence of a complex order parameter with continuous rotational symmetry, and the onset of quasi-long-range order as the system approaches a critical temperature. We describe and use a simple approach to statistical estimation with an annealing-based quantum processor that performs Monte Carlo sampling in a chain of reverse quantum annealing protocols. Observations are consistent with classical simulations across a range of Hamiltonian parameters. We anticipate that our approach of using a quantum processor as a programmable magnetic lattice will find widespread use in the simulation and development of exotic materials.

8.
Neuroimage ; 273: 120097, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37031827

RESUMO

The neurobiology of the psychedelic experience is not fully understood. Identifying common brain network changes induced by both classical (i.e., acting at the 5-HT2 receptor) and non-classical psychedelics would provide mechanistic insight into state-specific characteristics. We analyzed whole-brain functional connectivity based on resting-state fMRI data in humans, acquired before and during the administration of nitrous oxide, ketamine, and lysergic acid diethylamide. We report that, despite distinct molecular mechanisms and modes of delivery, all three psychedelics reduced within-network functional connectivity and enhanced between-network functional connectivity. More specifically, all three drugs increased connectivity between right temporoparietal junction and bilateral intraparietal sulcus as well as between precuneus and left intraparietal sulcus. These regions fall within the posterior cortical "hot zone," posited to mediate the qualitative aspects of experience. Thus, both classical and non-classical psychedelics modulate networks within an area of known relevance for consciousness, identifying a biologically plausible candidate for their subjective effects.


Assuntos
Alucinógenos , Ketamina , Humanos , Alucinógenos/farmacologia , Dietilamida do Ácido Lisérgico/farmacologia , Encéfalo , Ketamina/farmacologia , Estado de Consciência
9.
Emerg Infect Dis ; 29(9)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37610295

RESUMO

During 2006-2021, Canada had 55 laboratory-confirmed outbreaks of foodborne botulism, involving 67 cases. The mean annual incidence was 0.01 case/100,000 population. Foodborne botulism in Indigenous communities accounted for 46% of all cases, which is down from 85% of all cases during 1990-2005. Among all cases, 52% were caused by botulinum neurotoxin type E, but types A (24%), B (16%), F (3%), and AB (1%) also occurred; 3% were caused by undetermined serotypes. Four outbreaks resulted from commercial products, including a 2006 international outbreak caused by carrot juice. Hospital data indicated that 78% of patients were transferred to special care units and 70% required mechanical ventilation; 7 deaths were reported. Botulinum neurotoxin type A was associated with much longer hospital stays and more time spent in special care than types B or E. Foodborne botulism often is misdiagnosed. Increased clinician awareness can improve diagnosis, which can aid epidemiologic investigations and patient treatment.


Assuntos
Botulismo , Humanos , Botulismo/diagnóstico , Botulismo/epidemiologia , Canadá/epidemiologia , Surtos de Doenças , Hospitais , Laboratórios
10.
Epidemiol Infect ; 151: e154, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37675600

RESUMO

Clostridium botulinum causes infant botulism by colonising the intestines and producing botulinum neurotoxin in situ. Previous reports have linked infant botulism cases to C. botulinum spores in household dust, yet the baseline incidence of C. botulinum spores in residential households is currently unknown. Vacuum cleaner dust from 963 households in 13 major Canadian cities was tested for C. botulinum using a novel real-time PCR assay directed against all known subtypes of the botulinum neurotoxin gene. None of the samples tested positive for C. botulinum. Analysis of a random subset of samples by MALDI Biotyper revealed that the most common anaerobic bacterial isolates were of the genus Clostridium and the most common species recovered overall was Clostridium perfringens. Dust that was spiked with C. botulinum spores of each toxin type successfully produced positive real-time PCR reactions. These control experiments indicate that this is a viable method for the detection of C. botulinum spores in household dust. We make several recommendations for future work that may help discover a common environmental source of C. botulinum spores that could lead to effective preventative measures for this rare but deadly childhood disease.


Assuntos
Toxinas Botulínicas , Botulismo , Clostridium botulinum , Humanos , Lactente , Criança , Clostridium botulinum/genética , Botulismo/etiologia , Botulismo/microbiologia , Poeira/análise , Cidades , Esporos Bacterianos/química , Canadá/epidemiologia , Toxinas Botulínicas/genética
11.
Pain Med ; 24(Suppl 1): S81-S94, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-36069660

RESUMO

Management of patients suffering from low back pain (LBP) is challenging and requires development of diagnostic techniques to identify specific patient subgroups and phenotypes in order to customize treatment and predict clinical outcome. The Back Pain Consortium (BACPAC) Research Program Spine Imaging Working Group has developed standard operating procedures (SOPs) for spinal imaging protocols to be used in all BACPAC studies. These SOPs include procedures to conduct spinal imaging assessments with guidelines for standardizing the collection, reading/grading (using structured reporting with semi-quantitative evaluation using ordinal rating scales), and storage of images. This article presents the approach to image acquisition and evaluation recommended by the BACPAC Spine Imaging Working Group. While the approach is specific to BACPAC studies, it is general enough to be applied at other centers performing magnetic resonance imaging (MRI) acquisitions in patients with LBP. The herein presented SOPs are meant to improve understanding of pain mechanisms and facilitate patient phenotyping by codifying MRI-based methods that provide standardized, non-invasive assessments of spinal pathologies. Finally, these recommended procedures may facilitate the integration of better harmonized MRI data of the lumbar spine across studies and sites within and outside of BACPAC studies.


Assuntos
Degeneração do Disco Intervertebral , Dor Lombar , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Região Lombossacral , Dor Lombar/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
12.
Pain Med ; 24(Suppl 1): S95-S104, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-36721327

RESUMO

OBJECTIVE: One aim of the Back Pain Consortium (BACPAC) Research Program is to develop an integrated model of chronic low back pain that is informed by combined data from translational research and clinical trials. We describe efforts to maximize data harmonization and accessibility to facilitate Consortium-wide analyses. METHODS: Consortium-wide working groups established harmonized data elements to be collected in all studies and developed standards for tabular and nontabular data (eg, imaging and omics). The BACPAC Data Portal was developed to facilitate research collaboration across the Consortium. RESULTS: Clinical experts developed the BACPAC Minimum Dataset with required domains and outcome measures to be collected by use of questionnaires across projects. Other nonrequired domain-specific measures are collected by multiple studies. To optimize cross-study analyses, a modified data standard was developed on the basis of the Clinical Data Interchange Standards Consortium Study Data Tabulation Model to harmonize data structures and facilitate integration of baseline characteristics, participant-reported outcomes, chronic low back pain treatments, clinical exam, functional performance, psychosocial characteristics, quantitative sensory testing, imaging, and biomechanical data. Standards to accommodate the unique features of chronic low back pain data were adopted. Research units submit standardized study data to the BACPAC Data Portal, developed as a secure cloud-based central data repository and computing infrastructure for researchers to access and conduct analyses on data collected by or acquired for BACPAC. CONCLUSIONS: BACPAC harmonization efforts and data standards serve as an innovative model for data integration that could be used as a framework for other consortia with multiple, decentralized research programs.


Assuntos
Dor Lombar , Humanos , Dor Lombar/terapia , Avaliação de Resultados em Cuidados de Saúde , Projetos de Pesquisa
13.
Pain Med ; 24(Suppl 1): S126-S138, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-36708026

RESUMO

Evidence-based treatments for chronic low back pain (cLBP) typically work well in only a fraction of patients, and at present there is little guidance regarding what treatment should be used in which patients. Our central hypothesis is that an interventional response phenotyping study can identify individuals with different underlying mechanisms for their pain who thus respond differentially to evidence-based treatments for cLBP. Thus, we will conduct a randomized controlled Sequential, Multiple Assessment, Randomized Trial (SMART) design study in cLBP with the following three aims. Aim 1: Perform an interventional response phenotyping study in a cohort of cLBP patients (n = 400), who will receive a sequence of interventions known to be effective in cLBP. For 4 weeks, all cLBP participants will receive a web-based pain self-management program as part of a run-in period, then individuals who report no or minimal improvement will be randomized to: a) mindfulness-based stress reduction, b) physical therapy and exercise, c) acupressure self-management, and d) duloxetine. After 8 weeks, individuals who remain symptomatic will be re-randomized to a different treatment for an additional 8 weeks. Using those data, we will identify the subsets of participants that respond to each treatment. In Aim 2, we will show that currently available, clinically derived measures, can predict differential responsiveness to the treatments. In Aim 3, a subset of participants will receive deeper phenotyping (n = 160), to identify new experimental measures that predict differential responsiveness to the treatments, as well as to infer mechanisms of action. Deep phenotyping will include functional neuroimaging, quantitative sensory testing, measures of inflammation, and measures of autonomic tone.


Assuntos
Dor Crônica , Dor Lombar , Humanos , Dor Crônica/terapia , Dor Lombar/terapia , Modalidades de Fisioterapia , Projetos de Pesquisa , Cloridrato de Duloxetina , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
J Craniofac Surg ; 34(5): 1420-1426, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37101317

RESUMO

PURPOSE: Orbital volume increase has been previously linked with post-traumatic enophthalmos. However, this varies and some studies show no correlation. This systematic review and meta-analysis aimed to synthesize the correlation between orbital volume and enophthalmos and to determine if surgical intervention, enophthalmos measurement method, fracture location, or timing affect this correlation. METHODS: Automation tools were used to assist in this review of 6 databases. Searches were performed across all dates. Included studies quantitatively reported orbital volume and enophthalmos following traumatic orbital wall fractures in at least 5 adult subjects. Correlational data were extracted or calculated. Random-effects meta-analysis was used with subgroup analyses for each of the secondary aims. RESULTS: Twenty-five articles describing 648 patients were included. The pooled correlation between orbital volume and enophthalmos was r =0.71 ( R2 =0.50, P <0.001). Operative status, enophthalmos measurement method, and fracture location did not affect pooled correlation. The delay between trauma or surgery and enophthalmos measurement was not shown to modulate correlation for unoperated patients ( R2 =0.05, P =0.22) but showed a negative relationship for postoperative patients ( z =-0.0281, SE=0.0128, R2 =0.63, P =0.03), but this was heavily influenced by a single article. All results had high residual heterogeneity. Studies were rated as moderate, low, or very low quality with few stating explicit hypotheses or limitations. CONCLUSIONS: Bony orbital volume expansion accounts for around 50% of post-traumatic enophthalmos. The other half is probably explained by soft tissue or geometric bony, rather than volumetric, changes.


Assuntos
Enoftalmia , Traumatismos Oculares , Fraturas Orbitárias , Adulto , Humanos , Enoftalmia/etiologia , Enoftalmia/complicações , Fraturas Orbitárias/complicações , Fraturas Orbitárias/diagnóstico por imagem , Fraturas Orbitárias/cirurgia , Traumatismos Oculares/complicações , Automação , Órbita/cirurgia , Estudos Retrospectivos
15.
Neuromodulation ; 26(5): 999-1008, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34309138

RESUMO

OBJECTIVES: Although primary motor cortex (M1) transcranial direct current stimulation (tDCS) has an analgesic effect in fibromyalgia (FM), its neural mechanism remains elusive. We investigated whether M1-tDCS modulates a regional temporal variability of blood-oxygenation-level-dependent (BOLD) signals, an indicator of the brain's flexibility and efficiency and if this change is associated with pain improvement. MATERIALS AND METHODS: In a within-subjects cross-over design, 12 female FM patients underwent sham and active tDCS on five consecutive days, respectively. Each session was performed with an anode placed on the left M1 and a cathode on the contralateral supraorbital region. The subjects also participated in resting-state functional magnetic resonance imaging (fMRI) at baseline and after sham and active tDCS. We compared the BOLD signal variability (SDBOLD), defined as the standard deviation of the BOLD time-series, between the tDCS conditions. Baseline SDBOLD was compared to 15 healthy female controls. RESULTS: At baseline, FM patients showed reduced SDBOLD in the ventromedial prefrontal cortex (vmPFC), lateral PFC, and anterior insula and increased SDBOLD in the posterior insula compared to healthy controls. After active tDCS, compared to sham, we found an increased SDBOLD in the left rostral anterior cingulate cortex (rACC), lateral PFC, and thalamus. After sham tDCS, compared to baseline, we found a decreased SDBOLD in the dorsomedial PFC and posterior cingulate cortex/precuneus. Interestingly, after active tDCS compared to sham, pain reduction was correlated with an increased SDBOLD in the rACC/vmPFC but with a decreased SDBOLD in the posterior insula. CONCLUSION: Our findings suggest that M1-tDCS might revert temporal variability of fMRI signals in the rACC/vmPFC and posterior insula linked to FM pain. Changes in neural variability would be part of the mechanisms underlying repetitive M1-tDCS analgesia in FM.


Assuntos
Fibromialgia , Estimulação Transcraniana por Corrente Contínua , Feminino , Humanos , Fibromialgia/diagnóstico por imagem , Fibromialgia/terapia , Imageamento por Ressonância Magnética , Dor , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Estudos Cross-Over
16.
J Cancer Educ ; 38(6): 1871-1878, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37526910

RESUMO

Dietary supplements are commonly used among cancer survivors. Oncology providers rarely receive training about dietary supplements. We evaluated whether e-learning modules could improve oncology providers' dietary supplement knowledge. Oncology providers participated in the National Cancer Institute funded Integrative Oncology Scholars (IOS) program. We used posttest readiness assurance tests (RAT) to measure knowledge acquisition from modules. One cohort completed a pre and posttest RAT to assess change in knowledge. Multivariate linear regression models adjusted for gender, race, profession, and years in practice were used to determine if these characteristics were associated with posttest RAT performance and change in pre to posttest RAT scores. Scholars (N = 101) included 86% (N = 87) females; age 44 ± 10 years; 72% (N = 73) Non-Hispanic White; years in practice mean range 11-15 ± 10. There were 37 physicians, 11 physician assistants, 23 nurses, 21 social workers, 2 psychologists, 4 pharmacists, and 2 physical therapists. The posttest dietary supplement and antioxidant RAT scores for all Scholars were 67 ± 18% and 71 ± 14%. In adjusted models there were no significant associations between dietary supplement and antioxidant posttest RAT scores with Scholar characteristics. Change in RAT scores for dietary supplement and antioxidants were 25% ± 23 and 26% ± 27 (P < 0.0001). In adjusted models, there were no significant predictors of change in dietary supplement RATs. For antioxidant RATs, profession was associated with change in scores (P = 0.021). Improvement in Scholar's test scores demonstrate the IOS program can significantly increase oncology providers' knowledge of dietary supplements and antioxidants.


Assuntos
Oncologia Integrativa , Médicos , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Antioxidantes , Suplementos Nutricionais
17.
BMC Biol ; 19(1): 253, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34823526

RESUMO

BACKGROUND: Snakes and primates have a multi-layered coevolutionary history as predators, prey, and competitors with each other. Previous work has explored the Snake Detection Theory (SDT), which focuses on the role of snakes as predators of primates and argues that snakes have exerted a selection pressure for the origin of primates' visual systems, a trait that sets primates apart from other mammals. However, primates also attack and kill snakes and so snakes must simultaneously avoid primates. This factor has been recently highlighted in regard to the movement of hominins into new geographic ranges potentially exerting a selection pressure leading to the evolution of spitting in cobras on three independent occasions. RESULTS: Here, we provide further evidence of coevolution between primates and snakes, whereby through frequent encounters and reciprocal antagonism with large, diurnally active neurotoxic elapid snakes, Afro-Asian primates have evolved an increased resistance to α-neurotoxins, which are toxins that target the nicotinic acetylcholine receptors. In contrast, such resistance is not found in Lemuriformes in Madagascar, where venomous snakes are absent, or in Platyrrhini in the Americas, where encounters with neurotoxic elapids are unlikely since they are relatively small, fossorial, and nocturnal. Within the Afro-Asian primates, the increased resistance toward the neurotoxins was significantly amplified in the last common ancestor of chimpanzees, gorillas, and humans (clade Homininae). Comparative testing of venoms from Afro-Asian and American elapid snakes revealed an increase in α-neurotoxin resistance across Afro-Asian primates, which was likely selected against cobra venoms. Through structure-activity studies using native and mutant mimotopes of the α-1 nAChR receptor orthosteric site (loop C), we identified the specific amino acids responsible for conferring this increased level of resistance in hominine primates to the α-neurotoxins in cobra venom. CONCLUSION: We have discovered a pattern of primate susceptibility toward α-neurotoxins that supports the theory of a reciprocal coevolutionary arms-race between venomous snakes and primates.


Assuntos
Adaptação Fisiológica , Elapidae , Neurotoxinas , Animais , Venenos Elapídicos , Haplorrinos , Primatas
18.
Neuroimage ; 226: 117504, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33293261

RESUMO

Neuroimaging has enhanced our understanding of the neural correlates of pain. Yet, how neural circuits interact and contribute to persistent pain remain largely unknown. Here, we investigate the mesoscale organization of the brain through intrinsic functional communities generated from resting state functional MRI data from two independent datasets, a discovery cohort of 43 Fibromyalgia (FM) patients and 20 healthy controls (HC) as well as a replication sample of 34 FM patients and 21 HC. Using normalized mutual information, we found that the global network architecture in chronic pain patients is less stable (more variable). Subsequent analyses of node community assignment revealed the composition of the communities differed between FM and HC. Furthermore, differences in network organization were associated with the changes in the composition of communities between patients with varying levels of clinical pain. Together, this work demonstrates that intrinsic network communities differ substantially between patients with FM and controls. These differences may represent a novel aspect of the pathophysiology of chronic nociplastic pain.


Assuntos
Encéfalo/fisiopatologia , Dor Crônica/fisiopatologia , Fibromialgia/fisiopatologia , Interpretação de Imagem Assistida por Computador/métodos , Rede Nervosa/fisiopatologia , Adulto , Dor Crônica/etiologia , Feminino , Fibromialgia/complicações , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Neuroimagem/métodos , Adulto Jovem
19.
Anal Chem ; 93(7): 3403-3410, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33556238

RESUMO

Rapid, quantitative, and group-targeting detection of total benzodiazepines (BZDs) is critical to create an accurate judgement in emergent medical and forensic settings. Large-size (111) faceted Ag nanosheets decorated with small ZnO nanoparticles were designed as the prominent surface-enhanced Raman scattering substrate, which possessed advantages of specific metal facets and additional charge-transfer (CT) effect from the semiconductor. The vital and bridge role of ZnO in the CT effect was systematically studied via experimental investigations and molecular dynamics simulation, which proves the essentiality of an appropriate ZnO decoration density. Upon determining optimal Ag NS/ZnO hybrids, a calibration curve of estazolam was established with a 0.5 nM detection limit. Based on the obtained curve, group-targeting screening was achieved toward total concentrations of five BZDs (estazolam, oxazepam, alprazolam, triazolam, and lorazepam). Importantly, the total concentrations of BZDs in mice serum were accurately monitored with changing analytical time during the metabolic process, which was in agreement with the tendency measured by liquid chromatography with tandem mass spectrometry.

20.
Proc Biol Sci ; 288(1942): 20202703, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33434458

RESUMO

The evolution of venom resistance through coevolutionary chemical arms races has arisen multiple times throughout animalia. Prior documentation of resistance to snake venom α-neurotoxins consists of the N-glycosylation motif or the hypothesized introduction of arginine at positions 187 at the α-1 nicotinic acetylcholine receptor orthosteric site. However, no further studies have investigated the possibility of other potential forms of resistance. Using a biolayer interferometry assay, we first confirm that the previously hypothesized resistance conferred by arginine at position 187 in the honey badger does reduce binding to α-neurotoxins, which has never been functionally tested. We further discovered a novel form of α-neurotoxin resistance conferred by charge reversal mutations, whereby a negatively charged amino acid is replaced by the positively charged amino acid lysine. As venom α-neurotoxins have evolved strong positive charges on their surface to facilitate binding to the negatively charged α-1 orthosteric site, these mutations result in a positive charge/positive charge interaction electrostatically repelling the α-neurotoxins. Such a novel mechanism for resistance has gone completely undiscovered, yet this form of resistance has convergently evolved at least 10 times within snakes. These coevolutionary innovations seem to have arisen through convergent phenotypes to ultimately evolve a similar biophysical mechanism of resistance across snakes.


Assuntos
Neurotoxinas , Receptores Nicotínicos , Sequência de Aminoácidos , Animais , Mutação , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Eletricidade Estática
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