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1.
Nat Immunol ; 24(12): 2108-2120, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37932457

RESUMO

Regulatory T cells (Treg cells) are instrumental in establishing immunological tolerance. However, the precise effector mechanisms by which Treg cells control a specific type of immune response in a given tissue remains unresolved. By simultaneously studying Treg cells from different tissue origins under systemic autoimmunity, in the present study we show that interleukin (IL)-27 is specifically produced by intestinal Treg cells to regulate helper T17 cell (TH17 cell) immunity. Selectively increased intestinal TH17 cell responses in mice with Treg cell-specific IL-27 ablation led to exacerbated intestinal inflammation and colitis-associated cancer, but also helped protect against enteric bacterial infection. Furthermore, single-cell transcriptomic analysis has identified a CD83+CD62Llo Treg cell subset that is distinct from previously characterized intestinal Treg cell populations as the main IL-27 producers. Collectively, our study uncovers a new Treg cell suppression mechanism crucial for controlling a specific type of immune response in a particular tissue and provides further mechanistic insights into tissue-specific Treg cell-mediated immune regulation.


Assuntos
Interleucina-27 , Linfócitos T Reguladores , Camundongos , Animais , Linfócitos T Auxiliares-Indutores , Tolerância Imunológica , Imunidade Celular , Células Th17
2.
Proc Natl Acad Sci U S A ; 120(10): e2217564120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36853942

RESUMO

The field of plant science has grown dramatically in the past two decades, but global disparities and systemic inequalities persist. Here, we analyzed ~300,000 papers published over the past two decades to quantify disparities across nations, genders, and taxonomy in the plant science literature. Our analyses reveal striking geographical biases-affluent nations dominate the publishing landscape and vast areas of the globe have virtually no footprint in the literature. Authors in Northern America are cited nearly twice as many times as authors based in Sub-Saharan Africa and Latin America, despite publishing in journals with similar impact factors. Gender imbalances are similarly stark and show remarkably little improvement over time. Some of the most affluent nations have extremely male biased publication records, despite supposed improvements in gender equality. In addition, we find that most studies focus on economically important crop and model species, and a wealth of biodiversity is underrepresented in the literature. Taken together, our analyses reveal a problematic system of publication, with persistent imbalances that poorly capture the global wealth of scientific knowledge and biological diversity. We conclude by highlighting disparities that can be addressed immediately and offer suggestions for long-term solutions to improve equity in the plant sciences.


Assuntos
Biodiversidade , Equidade de Gênero , Feminino , Masculino , Humanos , Geografia , Conhecimento , América do Norte
3.
BMC Biol ; 22(1): 9, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233809

RESUMO

BACKGROUND: How novel phenotypes originate from conserved genes, processes, and tissues remains a major question in biology. Research that sets out to answer this question often focuses on the conserved genes and processes involved, an approach that explicitly excludes the impact of genetic elements that may be classified as clade-specific, even though many of these genes are known to be important for many novel, or clade-restricted, phenotypes. This is especially true for understudied phyla such as mollusks, where limited genomic and functional biology resources for members of this phylum have long hindered assessments of genetic homology and function. To address this gap, we constructed a chromosome-level genome for the gastropod Berghia stephanieae (Valdés, 2005) to investigate the expression of clade-specific genes across both novel and conserved tissue types in this species. RESULTS: The final assembled and filtered Berghia genome is comparable to other high-quality mollusk genomes in terms of size (1.05 Gb) and number of predicted genes (24,960 genes) and is highly contiguous. The proportion of upregulated, clade-specific genes varied across tissues, but with no clear trend between the proportion of clade-specific genes and the novelty of the tissue. However, more complex tissue like the brain had the highest total number of upregulated, clade-specific genes, though the ratio of upregulated clade-specific genes to the total number of upregulated genes was low. CONCLUSIONS: Our results, when combined with previous research on the impact of novel genes on phenotypic evolution, highlight the fact that the complexity of the novel tissue or behavior, the type of novelty, and the developmental timing of evolutionary modifications will all influence how novel and conserved genes interact to generate diversity.


Assuntos
Gastrópodes , Animais , Gastrópodes/genética , Filogenia , Evolução Molecular , Moluscos/genética , Cromossomos , Fenótipo , Expressão Gênica
4.
J Exp Bot ; 75(11): 3612-3623, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38511472

RESUMO

Desiccation tolerance evolved recurrently across diverse plant lineages to enable survival in water-limited conditions. Many resurrection plants are polyploid, and several groups have hypothesized that polyploidy contributed to the evolution of desiccation tolerance. However, due to the vast phylogenetic distance between resurrection plant lineages, the rarity of desiccation tolerance, and the prevalence of polyploidy in plants, this hypothesis has been difficult to test. Here, we surveyed natural variation in morphological, reproductive, and desiccation tolerance traits across several cytotypes of a single species to test for links between polyploidy and increased resilience. We sampled multiple natural populations of the resurrection grass Microchloa caffra across an environmental gradient ranging from mesic to xeric in South Africa. We describe two distinct ecotypes of M. caffra that occupy different extremes of the environmental gradient and exhibit consistent differences in ploidy, morphological, reproductive, and desiccation tolerance traits in both field and common growth conditions. Interestingly, plants with more polyploid genomes exhibited consistently higher recovery from desiccation, were less reproductive, and were larger than plants with smaller genomes and lower ploidy. These data indicate that selective pressures in increasingly xeric sites may play a role in maintaining and increasing desiccation tolerance and are mediated by changes in ploidy.


Assuntos
Poaceae , Poliploidia , Poaceae/genética , Poaceae/fisiologia , África do Sul , Dessecação , Adaptação Fisiológica/genética
5.
Microb Pathog ; 190: 106608, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38503396

RESUMO

The occurrence of bacterial resistance has been increasing, compromising the treatment of various infections. The high virulence of Staphylococcus aureus allows for the maintenance of the infectious process, causing many deaths and hospitalizations. The MepA and NorA efflux pumps are transporter proteins responsible for expelling antimicrobial agents such as fluoroquinolones from the bacterial cell. Coumarins are phenolic compounds that have been studied for their diverse biological actions, including against bacteria. A pharmacokinetic in silico characterization of compounds C10, C11, C13, and C14 was carried out according to the principles of Lipinski's Rule of Five, in addition to searching for similarity in ChemBL and subsequent search for publications in CAS SciFinder. All compounds were evaluated for their in vitro antibacterial and modulatory activity against standard and multidrug-resistant Gram-positive and Gram-negative strains. The effect of coumarins C9, C10, C11, C13, and C14 as efflux pump inhibitors in Staphylococcus aureus strains was evaluated using the microdilution method (MepA or NorA) and fluorimetry (NorA). The behavior of coumarins regarding the efflux pump was determined from their interaction properties with the membrane and coumarin-protein using molecular docking and molecular dynamics simulations. Only the isolated coumarin compound C13 showed antibacterial activity against standard strains of Staphylococcus aureus and Escherichia coli. However, the other tested coumarins showed modulatory capacity for fluoroquinolone and aminoglycoside antibacterials. Compounds C10, C13, and C14 were effective in reducing the MIC of both antibiotics for both multidrug-resistant strains, while C11 potentiated the effect of norfloxacin and gentamicin for Gram-positive and Gram-negative bacteria and only norfloxacin for Gram-negative. Only coumarin C14 produced synergistic effects when associated with ciprofloxacin in MepA-carrying strains. All tested coumarins have the ability to inhibit the NorA efflux pump present in Staphylococcus aureus, both in reducing the MIC and inducing increased ethidium bromide fluorescence emission in fluorimetry. The findings of this study offer an atomistic perspective on the potential of coumarins as active inhibitors of the NorA pump, highlighting their specific mode of action mainly targeting protein inhibition. In molecular docking, it was observed that coumarins are capable of interacting with various amino acid residues of the NorA pump. The simulation showed that coumarin C10 can cross the bilayer; however, the other coumarins interacted with the membrane but were unable to cross it. Coumarins demonstrated their potentiating role in the effect of norfloxacin through a dual mechanism: efflux pump inhibition through direct interaction with the protein (C9, C10, C11, and C13) and increased interaction with the membrane (C10 and C13). In the context of pharmacokinetic prediction studies, the studied structures have a suitable chemical profile for possible oral use. We suggest that coumarin derivatives may be an interesting alternative in the future for the treatment of resistant bacterial infections, with the possibility of a synergistic effect with other antibacterials, although further studies are needed to characterize their therapeutic effects and toxicity.


Assuntos
Antibacterianos , Proteínas de Bactérias , Cumarínicos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Staphylococcus aureus , Cumarínicos/farmacologia , Cumarínicos/química , Cumarínicos/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas/efeitos dos fármacos , Proteínas de Membrana Transportadoras/metabolismo
6.
Toxicol Appl Pharmacol ; : 117046, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39084266

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a progressive liver disease, affecting 32% of adults globally. If left untreated, NAFLD may progress to more advanced forms of the disease, including non-alcoholic steatohepatitis (NASH), liver cirrhosis, and fibrosis. Early NAFLD detection is critical to prevent disease progression. Using an obesogenic high-fat and high-sucrose (HF/HS) diet, we characterized the progression of NAFLD in male and female Collaborative Cross CC042 mice at 20-, 40-, and 60-week intervals of chronic HF/HS diet feeding. The incidence and severity of liver steatosis, inflammation, and fibrosis increased in both sexes over time, with male mice progressing to a NASH-like disease state faster than female mice, as indicated by earlier and more pronounced changes in liver steatosis. Histopathological indication of macrovesicular steatosis and gene expression changes of key lipid metabolism genes were found to be elevated in both sexes after 20 weeks of HF/HS diet. Measurement of circulating markers of inflammation (CXCL10 and TNF-α), histopathological analysis of immune cell infiltrates, and gene expression changes in inflammation-related genes indicated significant liver inflammation after 40 and 60 weeks of HF/HS diet exposure in both sexes. Liver fibrosis, as assessed by Picosirius red and Masson's trichrome staining and changes in expression of key fibrosis related genes indicated significant changes after 40 and 60 weeks of HF/HS diet exposure. In conclusion, we present a preclinical animal model of dietary NAFLD progression, which recapitulates human pathophysiological and pathomorphological changes, that could be used to better understand the progression of NAFLD and support development of new therapeutics.

7.
J Chem Phys ; 161(1)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38958156

RESUMO

Force Field X (FFX) is an open-source software package for atomic resolution modeling of genetic variants and organic crystals that leverages advanced potential energy functions and experimental data. FFX currently consists of nine modular packages with novel algorithms that include global optimization via a many-body expansion, acid-base chemistry using polarizable constant-pH molecular dynamics, estimation of free energy differences, generalized Kirkwood implicit solvent models, and many more. Applications of FFX focus on the use and development of a crystal structure prediction pipeline, biomolecular structure refinement against experimental datasets, and estimation of the thermodynamic effects of genetic variants on both proteins and nucleic acids. The use of Parallel Java and OpenMM combines to offer shared memory, message passing, and graphics processing unit parallelization for high performance simulations. Overall, the FFX platform serves as a computational microscope to study systems ranging from organic crystals to solvated biomolecular systems.


Assuntos
Software , Simulação de Dinâmica Molecular , Variação Genética , Algoritmos , Termodinâmica , Proteínas/química , Cristalização , Ácidos Nucleicos/química
8.
Nurs Educ Perspect ; 45(4): E25-E27, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38625709

RESUMO

ABSTRACT: This study used a quantitative descriptive survey with a sample of 92 participants to assess perceived nurse faculty competency in their role at Saudi Arabian universities. Participants' perceptions overall were highly positive in the areas of teaching, scholarship, and service competencies. Participants reported less competence in the areas of scholarship and service when they started in their role. Orientation and a mentor relationship with senior faculty were reported to aid in their transition to the faculty role. The findings of the study identify strategies to support the new nurse educator.


Assuntos
Docentes de Enfermagem , Humanos , Arábia Saudita , Docentes de Enfermagem/psicologia , Feminino , Masculino , Adulto , Inquéritos e Questionários , Competência Profissional/normas , Pessoa de Meia-Idade
9.
Augment Altern Commun ; 40(2): 69-73, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38487933

RESUMO

On February 2 2023, one of the guiding lights in the field of augmentative and alternative communication (AAC) for more than four decades, David E. Yoder, passed away at the age of 90. A voracious reader and gifted storyteller, David was particularly fond of a quote from George Bernard Shaw's Back to Methuselah, "You see things; and you say 'Why?' but I dream things that never were; and I say 'Why not?'" That vision led him to take on multiple leadership roles and influence the field of AAC in multiple ways. He played a pivotal role in establishing both the International Society for Augmentative and Alternative Communication (ISAAC) and the United States Society for Augmentative and Alternative Communication (USSAAC). Additionally, he chaired the panel for the National Institute on Disability and Rehabilitation Research (NIDRR)'s inaugural Consensus Validation Conference on AAC, advocated for the American Speech-Language-Hearing Association to recognize AAC within the profession's scope of practice, and served as the first editor for the Augmentative and Alternative Communication journal. In this tribute, we describe David's diverse and unique contributions to improving the lives of people with communication challenges with a focus on some of his central insights and actions.


Assuntos
Auxiliares de Comunicação para Pessoas com Deficiência , Auxiliares de Comunicação para Pessoas com Deficiência/história , Humanos , História do Século XXI , História do Século XX , Estados Unidos , Transtornos da Comunicação/reabilitação , Transtornos da Comunicação/história
10.
J Infect Dis ; 228(9): 1253-1262, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37439701

RESUMO

BACKGROUND: We compared homologous and heterologous boosting in adults in the Philippines primed with 2 or 3 doses of CoronaVac, with recombinant protein vaccine, SCB-2019. METHODS: CoronaVac-immunized adults (18-72 years) received a homologous or heterologous full or half dose SCB-2019 booster. We assessed all neutralizing antibody (NAb) responses against prototype SARS-CoV-2 after 15 days and NAb against SARS-CoV-2 Delta and Omicron variants in subsets (30‒50 per arm). Participants recorded adverse events. RESULTS: In 2-dose CoronaVac-primed adults prototype NAb geometric mean titers (GMT) were 203 IU/mL (95% confidence interval [CI], 182-227) and 939 IU/mL (95% CI, 841-1049) after CoronaVac and SCB-2019 boosters; the GMT ratio (4.63; 95% CI, 3.95-5.41) met predefined noninferiority and post-hoc superiority criteria. After 3-dose CoronaVac-priming prototype NAb GMTs were 279 IU/mL (95% CI, 240-325), 1044 IU/mL (95% CI, 898-1213), and 668 IU/mL (95% CI, 520-829) following CoronaVac, full and half-dose SCB-2019 boosters, respectively. NAb GMT ratios against Delta and Omicron comparing SCB-2019 with CoronaVac were all greater than 2. Mild to moderate reactogenicity was evenly balanced between groups. No vaccine-related serious adverse events were reported. CONCLUSIONS: Full or half dose SCB-2019 boosters were well tolerated with superior immunogenicity than homologous CoronaVac, particularly against newly emerged variants. Clinical Trials Registration. NCT05188677.


Assuntos
COVID-19 , Humanos , Adulto , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Imunogenicidade da Vacina
11.
Am J Physiol Gastrointest Liver Physiol ; 324(3): G232-G243, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36625475

RESUMO

Nonalcoholic fatty liver disease (NAFLD), the most prevalent chronic liver disease, is characterized by substantial variations in case-level severity. In this study, we used a genetically diverse Collaborative Cross (CC) mouse population model to analyze the global transcriptome and clarify the molecular mechanisms involved in hepatic fat accumulation that determine the level and severity of NAFLD. Twenty-four strains of male CC mice were maintained on a high-fat/high-sucrose (HF/HS) diet for 12 wk, and their hepatic gene expression profiles were determined by next-generation RNA sequencing. We found that the development of the nonalcoholic fatty liver (NAFL) phenotype in CC mice coincided with significant changes in the expression of hepatic genes at the population level, evidenced by the presence of 724 differentially expressed genes involved in lipid and carbohydrate metabolism, cell morphology, vitamin and mineral metabolism, energy production, and DNA replication, recombination, and repair. Importantly, expression of 68 of these genes strongly correlated with the extent of hepatic lipid accumulation in the overall population of HF/HS diet-fed male CC mice. Results of partial least squares (PLS) modeling showed that these derived hepatic gene expression signatures help to identify the individual mouse strains that are highly susceptible to the development of NAFLD induced by an HF/HS diet. These findings imply that gene expression profiling, combined with a PLS modeling approach, may be a useful tool to predict NAFLD severity in genetically diverse patient populations.NEW & NOTEWORTHY Feeding male Collaborative Cross mice an obesogenic diet allows modeling NAFLD at the population level. The development of NAFLD coincided with significant hepatic transcriptomic changes in this model. Genes (724) were differentially expressed and expression of 68 genes strongly correlated with the extent of hepatic lipid accumulation. Partial least squares modeling showed that derived hepatic gene expression signatures may help to identify individual mouse strains that are highly susceptible to the development of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Masculino , Humanos , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/metabolismo , Transcriptoma , Camundongos de Cruzamento Colaborativo/genética , Sacarose/metabolismo , Fígado/metabolismo , Dieta Hiperlipídica , Lipídeos , Camundongos Endogâmicos C57BL , Metabolismo dos Lipídeos
12.
Hum Genet ; 142(6): 819-834, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37086329

RESUMO

Hearing loss is the leading sensory deficit, affecting ~ 5% of the population. It exhibits remarkable heterogeneity across 223 genes with 6328 pathogenic missense variants, making deafness-specific expertise a prerequisite for ascribing phenotypic consequences to genetic variants. Deafness-implicated variants are curated in the Deafness Variation Database (DVD) after classification by a genetic hearing loss expert panel and thorough informatics pipeline. However, seventy percent of the 128,167 missense variants in the DVD are "variants of uncertain significance" (VUS) due to insufficient evidence for classification. Here, we use the deep learning protein prediction algorithm, AlphaFold2, to curate structures for all DVD genes. We refine these structures with global optimization and the AMOEBA force field and use DDGun3D to predict folding free energy differences (∆∆GFold) for all DVD missense variants. We find that 5772 VUSs have a large, destabilizing ∆∆GFold that is consistent with pathogenic variants. When also filtered for CADD scores (> 25.7), we determine 3456 VUSs are likely pathogenic at a probability of 99.0%. Of the 224 genes in the DVD, 166 genes (74%) exhibit one or more missense variants predicted to cause a pathogenic change in protein folding stability. The VUSs prioritized here affect 119 patients (~ 3% of cases) sequenced by the OtoSCOPE targeted panel. Approximately half of these patients previously received an inconclusive report, and reclassification of these VUSs as pathogenic provides a new genetic diagnosis for six patients.


Assuntos
Surdez , Perda Auditiva , Humanos , Proteoma/genética , Perda Auditiva/genética , Mutação de Sentido Incorreto , Surdez/genética
13.
Lancet ; 399(10323): 461-472, 2022 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-35065705

RESUMO

BACKGROUND: A range of safe and effective vaccines against SARS CoV 2 are needed to address the COVID 19 pandemic. We aimed to assess the safety and efficacy of the COVID-19 vaccine SCB-2019. METHODS: This ongoing phase 2 and 3 double-blind, placebo-controlled trial was done in adults aged 18 years and older who were in good health or with a stable chronic health condition, at 31 sites in five countries (Belgium, Brazil, Colombia, Philippines, and South Africa). The participants were randomly assigned 1:1 using a centralised internet randomisation system to receive two 0·5 mL intramuscular doses of SCB-2019 (30 µg, adjuvanted with 1·50 mg CpG-1018 and 0·75 mg alum) or placebo (0·9% sodium chloride for injection supplied in 10 mL ampoules) 21 days apart. All study staff and participants were masked, but vaccine administrators were not. Primary endpoints were vaccine efficacy, measured by RT-PCR-confirmed COVID-19 of any severity with onset from 14 days after the second dose in baseline SARS-CoV-2 seronegative participants (the per-protocol population), and the safety and solicited local and systemic adverse events in the phase 2 subset. This study is registered on EudraCT (2020-004272-17) and ClinicalTrials.gov (NCT04672395). FINDINGS: 30 174 participants were enrolled from March 24, 2021, until the cutoff date of Aug 10, 2021, of whom 30 128 received their first assigned vaccine (n=15 064) or a placebo injection (n=15 064). The per-protocol population consisted of 12 355 baseline SARS-CoV-2-naive participants (6251 vaccinees and 6104 placebo recipients). Most exclusions (13 389 [44·4%]) were because of seropositivity at baseline. There were 207 confirmed per-protocol cases of COVID-19 at 14 days after the second dose, 52 vaccinees versus 155 placebo recipients, and an overall vaccine efficacy against any severity COVID-19 of 67·2% (95·72% CI 54·3-76·8), 83·7% (97·86% CI 55·9-95·4) against moderate-to-severe COVID-19, and 100% (97·86% CI 25·3-100·0) against severe COVID-19. All COVID-19 cases were due to virus variants; vaccine efficacy against any severity COVID-19 due to the three predominant variants was 78·7% (95% CI 57·3-90·4) for delta, 91·8% (44·9-99·8) for gamma, and 58·6% (13·3-81·5) for mu. No safety issues emerged in the follow-up period for the efficacy analysis (median of 82 days [IQR 63-103]). The vaccine elicited higher rates of mainly mild-to-moderate injection site pain than the placebo after the first (35·7% [287 of 803] vs 10·3% [81 of 786]) and second (26·9% [189 of 702] vs 7·4% [52 of 699]) doses, but the rates of other solicited local and systemic adverse events were similar between the groups. INTERPRETATION: Two doses of SCB-2019 vaccine plus CpG and alum provides notable protection against the entire severity spectrum of COVID-19 caused by circulating SAR-CoV-2 viruses, including the predominating delta variant. FUNDING: Clover Biopharmaceuticals and the Coalition for Epidemic Preparedness Innovations.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Vacinas contra COVID-19/uso terapêutico , COVID-19/prevenção & controle , Glicoproteína da Espícula de Coronavírus/uso terapêutico , Adolescente , Adulto , Idoso , Compostos de Alúmen/uso terapêutico , Bélgica , Brasil , Colômbia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oligodesoxirribonucleotídeos/uso terapêutico , Filipinas , Multimerização Proteica , Proteínas Recombinantes/uso terapêutico , Risco , SARS-CoV-2 , África do Sul , Eficácia de Vacinas , Adulto Jovem
14.
Langmuir ; 39(4): 1414-1424, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36688667

RESUMO

Biocompatible tripeptide self-assembled monolayers (SAMs) are designed with a carboxylate group on the terminal amino acid (glutamate, aspartate, or amino adipate) to electrostatically attract the lysine groups around the heme crevice in horse heart cytochrome c (cyt c), creating an electroactive protein/tripeptide/Au interfacial structure. Exposing the peptide/Au electrode to cyt c resulted in an 11 ± 3 pmol/cm2 electroactive protein surface coverage. Topographical images of the interfacial structure are obtained down to single-protein resolution by atomic force microscopy. Uniform protein monolayer assemblies are formed on the Au electrode with no major surface roughness changes. The cyt c/peptide/Au electrode systems were examined electrochemically to probe surface charge effects on the redox thermodynamics and kinetics of cyt c. Neutralization of protein surface charge due to adsorption on anionic COOH-terminated SAMs was found to change the formal potential, as determined by cyclic voltammetry. The cyt c/peptide/Au electrodes exhibit formal potentials shifted to more positive values, have a surface carboxylic acid pKa of 6 or higher, and produce effective cyt c surface charges (Zox) of -6 to -14. The Marcus theory is utilized to determine the protein electron transfer rates, which are ∼5 times faster for cyt c/tripeptide/Au compared to cyt c/11-mercaptoundecanoic acid SAMs of similar chain lengths.


Assuntos
Citocromos c , Proteínas , Animais , Cavalos , Citocromos c/química , Eletroquímica , Oxirredução , Transporte de Elétrons , Peptídeos , Eletrodos , Ouro/química
15.
Br J Nutr ; 130(2): 268-275, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34895361

RESUMO

This was a longitudinal study utilising the Irish Longitudinal Study on Ageing (n 3849 aged ≥ 50 years) and investigated the relationship between blood plasma folate and B12 levels at baseline (wave 1) and incident depressive symptoms at 2 and 4 years (waves 2 and 3). A score ≥ 9 on the Center for Epidemiological Studies Depression Scale-8 at wave 2 or 3 was indicative of incident depressive symptoms. B12 status profiles (pmol/l) were defined as < 185, deficient low; 185 to < 258, low normal; > 258-601, normal and > 601 high. Folate status profiles (nmol/l) were defined as ≤ 10·0, deficient low; > 10-23·0, low normal; > 23·0-45·0, normal; >45·0, high. Logistic regression models were used to analyse the longitudinal associations. Both B12 and folate plasma concentrations were lower in the group with incident depressive symptoms v. non-depressed (folate: 21·4 v. 25·1 nmol/l; P = 0·0003; B12:315·7 v. 335·9 pmol/l; P = 0·0148). Regression models demonstrated that participants with deficient-low B12 status at baseline had a significantly higher likelihood of incident depression 4 years later (OR 1·51, 95 % CI 1·01, 2·27, P = 0·043). This finding remained robust after controlling for relevant covariates. No associations of folate status with incident depression were observed. Older adults with deficient-low B12 status had a 51 % increased likelihood of developing depressive symptoms over 4 years. The findings highlight the need to further explore the low-cost benefits of optimising vitamin B12 status for depression in older adults.


Assuntos
Depressão , Ácido Fólico , Humanos , Idoso , Estudos Longitudinais , Depressão/epidemiologia , Vida Independente , Vitaminas
16.
BMC Pregnancy Childbirth ; 23(1): 128, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36855094

RESUMO

BACKGROUND: As a teratogen, alcohol exposure during pregnancy can impact fetal development and result in adverse birth outcomes. Despite the clinical and social importance of prenatal alcohol use, limited routinely collected information or epidemiological data exists in Canada. The aim of this study was to pool data from multiple Canadian cohort studies to identify sociodemographic characteristics before and during pregnancy that were associated with alcohol consumption during pregnancy and to assess the impact of different patterns of alcohol use on birth outcomes. METHODS: We harmonized information collected (e.g., pregnant women's alcohol intake, infants' gestational age and birth weight) from five Canadian pregnancy cohort studies to consolidate a large sample (n = 11,448). Risk factors for any alcohol use during pregnancy, including any alcohol use prior to pregnancy recognition, and binge drinking, were estimated using binomial regressions including fixed effects of pregnancy cohort membership and multiple maternal risk factors. Impacts of alcohol use during pregnancy on birth outcomes (preterm birth and low birth weight for gestational) were also estimated using binomial regression models. RESULTS: In analyses adjusting for multiple risk factors, women's alcohol use during pregnancy, both any use and any binge drinking, was associated with drinking prior to pregnancy, smoking during pregnancy, and white ethnicity. Higher income level was associated with any drinking during pregnancy. Neither drinking during pregnancy nor binge drinking during pregnancy was significantly associated with preterm delivery or low birth weight for gestational age in our sample. CONCLUSIONS: Pooling data across pregnancy cohort studies allowed us to create a large sample of Canadian women and investigate the risk factors for alcohol consumption during pregnancy. We suggest that future pregnancy and birth cohorts should always include questions related to the frequency and amount of alcohol consumed before and during pregnancy that are prospectively harmonized to support data reusability and collaborative research.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas , Nascimento Prematuro , Efeitos Tardios da Exposição Pré-Natal , Recém-Nascido , Gravidez , Lactente , Feminino , Humanos , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Consumo Excessivo de Bebidas Alcoólicas/epidemiologia , Canadá/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Estudos de Coortes , Etanol
17.
Artif Organs ; 47(9): 1442-1451, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37376726

RESUMO

BACKGROUND: Extracorporeal organ assist devices provide lifesaving functions for acutely and chronically ill patients suffering from respiratory and renal failure, but their availability and use is severely limited by an extremely high level of operational complexity. While current hollow fiber-based devices provide high-efficiency blood gas transfer and waste removal in extracorporeal membrane oxygenation (ECMO) and hemodialysis, respectively, their impact on blood health is often highly deleterious and difficult to control. Further challenges are encountered when integrating multiple organ support functions, as is often required when ECMO and ultrafiltration (UF) are combined to deal with fluid overload in critically ill patients, necessitating an unwieldy circuit containing two separate cartridges. METHODS: We report the first laboratory demonstration of simultaneous blood gas oxygenation and fluid removal in single microfluidic circuit, an achievement enabled by the microchannel-based blood flow configuration of the device. Porcine blood is flowed through a stack of two microfluidic layers, one with a non-porous, gas-permeable silicone membrane separating blood and oxygen chambers, and the other containing a porous dialysis membrane separating blood and filtrate compartments. RESULTS: High levels of oxygen transfer are measured across the oxygenator, while tunable rates of fluid removal, governed by the transmembrane pressure (TMP), are achieved across the UF layer. Key parameters including the blood flow rate, TMP and hematocrit are monitored and compared with computationally predicted performance metrics. CONCLUSIONS: These results represent a model demonstration of a potential future clinical therapy where respiratory support and fluid removal are both realized through a single monolithic cartridge.


Assuntos
Oxigenação por Membrana Extracorpórea , Microfluídica , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Oxigênio , Hemodinâmica/fisiologia , Silicones
18.
Proc Natl Acad Sci U S A ; 117(41): 25722-25731, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32958655

RESUMO

Asymptomatic carriers of Plasmodium parasites hamper malaria control and eradication. Achieving malaria eradication requires ultrasensitive diagnostics for low parasite density infections (<100 parasites per microliter blood) that work in resource-limited settings (RLS). Sensitive point-of-care diagnostics are also lacking for nonfalciparum malaria, which is characterized by lower density infections and may require additional therapy for radical cure. Molecular methods, such as PCR, have high sensitivity and specificity, but remain high-complexity technologies impractical for RLS. Here we describe a CRISPR-based diagnostic for ultrasensitive detection and differentiation of Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, and Plasmodium malariae, using the nucleic acid detection platform SHERLOCK (specific high-sensitivity enzymatic reporter unlocking). We present a streamlined, field-applicable, diagnostic comprised of a 10-min SHERLOCK parasite rapid extraction protocol, followed by SHERLOCK for 60 min for Plasmodium species-specific detection via fluorescent or lateral flow strip readout. We optimized one-pot, lyophilized, isothermal assays with a simplified sample preparation method independent of nucleic acid extraction, and showed that these assays are capable of detection below two parasites per microliter blood, a limit of detection suggested by the World Health Organization. Our P. falciparum and P. vivax assays exhibited 100% sensitivity and specificity on clinical samples (5 P. falciparum and 10 P. vivax samples). This work establishes a field-applicable diagnostic for ultrasensitive detection of asymptomatic carriers as well as a rapid point-of-care clinical diagnostic for nonfalciparum malaria species and low parasite density P. falciparum infections.


Assuntos
Portador Sadio/diagnóstico , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Técnicas e Procedimentos Diagnósticos , Técnicas Genéticas , Malária/diagnóstico , Plasmodium/genética , Plasmodium/isolamento & purificação , Portador Sadio/parasitologia , Humanos , Malária/parasitologia , Plasmodium/classificação , Plasmodium/fisiologia
19.
Harm Reduct J ; 20(1): 81, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37380995

RESUMO

OBJECTIVES: Fentanyl has contributed to a sharp rise in the toxicity of the unregulated drug supply and fatal overdoses in Canada. It has also changed injection practices. Injection frequency has increased as a result and so has equipment sharing and health-related risks. The aim of this analysis was to explore the impact of safer supply programs on injection practices from the perspective of clients and providers in Ontario, Canada. METHODS: The data set included qualitative interviews with 52 clients and 21 providers that were conducted between February and October 2021 across four safer supply programs. Interview excerpts discussing injection practices were extracted, screened, coded and then grouped into themes. RESULTS: We identified three themes, each theme corresponding to a change in injection practices. The first change was a decrease in the amount of fentanyl used and a decrease in injection frequency. The second change involved switching to injecting hydromorphone tablets instead of fentanyl. Finally, the third change was stopping injecting altogether and taking safer supply medications orally. CONCLUSION: Safer supply programs can contribute to reducing injection-related health risks in addition to overdose risks. More specifically, they have the potential to address disease prevention and health promotion gaps that stand-alone downstream harm reduction interventions cannot address, by working upstream and providing a safer alternative to fentanyl.


Assuntos
Overdose de Drogas , Humanos , Ontário , Overdose de Drogas/prevenção & controle , Fentanila , Redução do Dano , Promoção da Saúde
20.
J Clin Psychol Med Settings ; 30(4): 909-923, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36869987

RESUMO

Providing effective healthy behavior change interventions within primary care presents numerous challenges. Obesity, tobacco use, and sedentary lifestyle negatively impact the health quality of numerous medical patients, particularly in underserved patient populations with limited resources. Primary Care Behavioral Health (PCBH) models, which incorporate a Behavioral Health Consultant (BHC), can offer point-of-contact psychological consultation, treatment, and also provide opportunities for interdisciplinary psychologist-physician clinical partnerships to pair a BHC's health behavior change expertise with the physician's medical care. Such models can also enhance medical training programs by providing resident physicians with live, case-based learning opportunities when partnered with a BHC to address patient health behaviors. We will describe the development, implementation, and preliminary outcomes of a PCBH psychologist-physician interdisciplinary health behavior change clinic within a Family Medicine residency program. Patient outcomes revealed significant reductions (p < .01) in weight, BMI, and tobacco use. Implications and future directions are discussed.


Assuntos
Atenção Primária à Saúde , Psiquiatria , Humanos , Comportamentos Relacionados com a Saúde , Modelos Teóricos
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