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1.
Lancet Microbe ; 5(4): e335-e344, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484748

RESUMO

BACKGROUND: The origin of novel SARS-CoV-2 spike sequences found in wastewater, without corresponding detection in clinical specimens, remains unclear. We sought to determine the origin of one such cryptic wastewater lineage by tracking and characterising its persistence and genomic evolution over time. METHODS: We first detected a cryptic lineage, WI-CL-001, in municipal wastewater in Wisconsin, USA, in January, 2022. To determine the source of WI-CL-001, we systematically sampled wastewater from targeted sub-sewershed lines and maintenance holes using compositing autosamplers. Viral concentrations in wastewater samples over time were measured by RT digital PCR. In addition to using metagenomic 12s rRNA sequencing to determine the virus's host species, we also sequenced SARS-CoV-2 spike receptor binding domains, and, where possible, whole viral genomes to identify and characterise the evolution of this lineage. FINDINGS: We traced WI-CL-001 to its source at a single commercial building. There we detected the cryptic lineage at concentrations as high as 2·7 × 109 genome copies per L. The majority of 12s rRNA sequences detected in wastewater leaving the identified source building were human. Additionally, we generated over 100 viral receptor binding domain and whole-genome sequences from wastewater samples containing the cryptic lineage collected over the 13 consecutive months this virus was detectable (January, 2022, to January, 2023). These sequences contained a combination of fixed nucleotide substitutions characteristic of Pango lineage B.1.234, which circulated in humans in Wisconsin at low levels from October, 2020, to February, 2021. Despite this, mutations in the spike gene and elsewhere resembled those subsequently found in omicron variants. INTERPRETATION: We propose that prolonged detection of WI-CL-001 in wastewater indicates persistent shedding of SARS-CoV-2 from a single human initially infected by an ancestral B.1.234 virus. The accumulation of convergent omicron-like mutations in WI-CL-001's ancestral B.1.234 genome probably reflects persistent infection and extensive within-host evolution. People who shed cryptic lineages could be an important source of highly divergent viruses that sporadically emerge and spread. FUNDING: The Rockefeller Foundation, Wisconsin Department of Health Services, Centers for Disease Control and Prevention, National Institute on Drug Abuse, and the Center for Research on Influenza Pathogenesis and Transmission.


Assuntos
COVID-19 , Águas Residuárias , Estados Unidos , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Centers for Disease Control and Prevention, U.S.
2.
Virus Evol ; 9(2): veac104, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692895

RESUMO

Prolonged infections in immunocompromised individuals may be a source for novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants, particularly when both the immune system and antiviral therapy fail to clear the infection and enable within-host evolution. Here we describe a 486-day case of SARS-CoV-2 infection in an immunocompromised individual. Following monotherapy with the monoclonal antibody Bamlanivimab, the individual's virus acquired resistance, likely via the earliest known occurrence of Spike amino acid variant E484T. Recently, E484T has arisen again as a derivative of E484A in the Omicron Variant of Concern, supporting the hypothesis that prolonged infections can give rise to novel variants long before they become prevalent in the human population.

3.
Environ Sci Technol ; 57(28): 10151-10172, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37364241

RESUMO

Passive sampling devices (PSDs) are increasingly used at contaminated sites to improve the characterization of contaminant transport and assessment of ecological and human health risk at sediment sites and to evaluate the effectiveness of remedial actions. The use of PSDs after full-scale remediation remains limited, however, in favor of evaluation based on conventional metrics, such as bulk sediment concentrations or bioaccumulation. This review has three overall aims: (1) identify sites where PSDs have been used to support cleanup efforts, (2) assess how PSD-derived remedial end points compare to conventional metrics, and (3) perform broad semiquantitative and selective quantitative concurrence analyses to evaluate the magnitude of agreement between metrics. Contaminated sediment remedies evaluated included capping, in situ amendment, dredging and monitored natural recovery (MNR). We identify and discuss 102 sites globally where PSDs were used to determine remedial efficacy resulting in over 130 peer-reviewed scientific publications and numerous technical reports and conference proceedings. The most common conventional metrics assessed alongside PSDs in the peer-reviewed literature were bioaccumulation (39%), bulk sediments (40%), toxicity (14%), porewater grab samples (16%), and water column grab samples (16%), while about 25% of studies used PSDs as the sole metric. In a semiquantitative concurrence analysis, the PSD-based metrics agreed with conventional metrics in about 68% of remedy assessments. A more quantitative analysis of reductions in bioaccumulation after remediation (i.e., remediation was successful) showed that decreases in uptake into PSDs agreed with decreases in bioaccumulation (within a factor of 2) 61% of the time. Given the relatively good agreement between conventional and PSD-based metrics, we propose several practices and areas for further study to enhance the utilization of PSDs throughout the remediation of contaminated sediment sites.


Assuntos
Recuperação e Remediação Ambiental , Poluentes Químicos da Água , Humanos , Benchmarking , Sedimentos Geológicos/análise , Poluentes Químicos da Água/toxicidade , Monitoramento Ambiental
4.
High Educ (Dordr) ; 85(3): 503-520, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35431321

RESUMO

Flipped classrooms have become widely adopted in educational settings (e.g., in higher education) worldwide. However, there is a need for more precise understanding of the ingredients for student satisfaction in a flipped setting. The aim of this paper was to investigate university students' experiences of the factors that create a successful flipped course. Ten measures were used to investigate the hypothesized factors affecting satisfaction, which were chosen based on the results from previous flipped classroom studies and higher educational research. These measures were grouped into three dimensions: (1) pedagogical (five measures), (2) social (three measures), and (3) technological (two measures). Exploratory factor analysis was run to analyze the adequacy of the instruments. Results revealed that the factor structure was as expected and that the instruments measuring all ten factors of teaching and learning in a flipped classroom were adequate. Furthermore, confirmatory factor analysis was used to formally operationalize the hypothesized latent constructs, and to build a structural equation model for predicting the student satisfaction of a flipped classroom. In the end, seven factors were found to predict student satisfaction with flipped courses. The highest predictor was guidance from the dimension of pedagogy, and the second-best predictor was experienced teaching for understanding. The results, limitations, and conclusion are discussed in terms of key issues and the development of a flipped classroom pedagogical design for higher education.

5.
Res Child Adolesc Psychopathol ; 51(4): 557-569, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36580170

RESUMO

Levels of emotional and behavioral problems in children and adolescents demonstrate secular changes over time, warranting ongoing investigation. Prior studies examining secular trends in a range of such problems have been conducted in the U.S. and internationally. Research in this area generally has not fully considered the school setting. This study compared emotional and behavioral problems across two cohorts of students in the U.S. assessed over a 22-year time period as part of measurement development efforts for the Scales for Assessing Emotional Disturbance Rating Scale (SAED-RSRS; Epstein et al., 2020). Specifically, analyses drew from data collected via teacher report on matched cohorts of students for the 1998 (data collected from 1996 to 1997; n = 1,148) and 2020 (data collected from 2016 to 2018; n = 1,148) editions of the SAED-RS. After establishing measurement invariance across cohorts and testing for gender differences, structural equation modeling revealed statistically significant cohort mean differences on two of the five factors of the SAED-RS, suggesting increases over time in Inability to Learn (ß = 0.09, p = .024) and Physical Symptoms and Fears (ß = 0.14, p = .005) that were comparable for girls and boys. There were no statistically significant differences on the remaining factors: Relationship Problems, Inappropriate Behavior, and Unhappiness/Depression. Supplemental item-level tests revealed differences on 8 of the 39 SAED-RS items. Findings suggest increases in specific problem areas that could benefit from ongoing monitoring and targeted interventions to support contemporary students.


Assuntos
Comportamento Problema , Masculino , Criança , Adolescente , Feminino , Humanos , Comportamento Problema/psicologia , Estudos Transversais , Emoções , Estudantes/psicologia , Estudos de Coortes
6.
MAbs ; 14(1): 2146629, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36433737

RESUMO

Self-association governs the viscosity and solubility of therapeutic antibodies in high-concentration formulations used for subcutaneous delivery, yet it is difficult to reliably identify candidates with low self-association during antibody discovery and early-stage optimization. Here, we report a high-throughput protein engineering method for rapidly identifying antibody candidates with both low self-association and high affinity. We find that conjugating quantum dots to IgGs that strongly self-associate (pH 7.4, PBS), such as lenzilumab and bococizumab, results in immunoconjugates that are highly sensitive for detecting other high self-association antibodies. Moreover, these conjugates can be used to rapidly enrich yeast-displayed bococizumab sub-libraries for variants with low levels of immunoconjugate binding. Deep sequencing and machine learning analysis of the enriched bococizumab libraries, along with similar library analysis for antibody affinity, enabled identification of extremely rare variants with co-optimized levels of low self-association and high affinity. This analysis revealed that co-optimizing bococizumab is difficult because most high-affinity variants possess positively charged variable domains and most low self-association variants possess negatively charged variable domains. Moreover, negatively charged mutations in the heavy chain CDR2 of bococizumab, adjacent to its paratope, were effective at reducing self-association without reducing affinity. Interestingly, most of the bococizumab variants with reduced self-association also displayed improved folding stability and reduced nonspecific binding, revealing that this approach may be particularly useful for identifying antibody candidates with attractive combinations of drug-like properties.Abbreviations: AC-SINS: affinity-capture self-interaction nanoparticle spectroscopy; CDR: complementarity-determining region; CS-SINS: charge-stabilized self-interaction nanoparticle spectroscopy; FACS: fluorescence-activated cell sorting; Fab: fragment antigen binding; Fv: fragment variable; IgG: immunoglobulin; QD: quantum dot; PBS: phosphate-buffered saline; VH: variable heavy; VL: variable light.


Assuntos
Imunoconjugados , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Afinidade de Anticorpos , Sítios de Ligação de Anticorpos , Regiões Determinantes de Complementaridade , Aprendizado de Máquina
7.
BMJ Open ; 12(10): e063594, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36270757

RESUMO

PURPOSE: Risk factor-based models struggle to accurately predict the development of cardiovascular disease (CVD) at the level of the individual. Ways of identifying people with low predicted risk who will develop CVD would allow stratified advice and support informed treatment decisions about the initiation or adjustment of preventive medication, and this is the aim of this prospective cohort study. PARTICIPANTS: The Tayside Screening for Cardiac Events (TASCFORCE) study recruited men and women aged≥40 years, free from known CVD, with a predicted 10-year risk of coronary heart disease<20%. If B-type natriuretic peptide (BNP) was greater than their gender median, participants were offered a whole-body contrast-enhanced MRI (WBCE-MRI) scan (cardiac imaging, whole-body angiography to determine left ventricular parameters, delayed gadolinium enhancement, atheroma burden). Blood, including DNA, was stored for future biomarker assays. Participants are being followed up using electronic record-linkage cardiovascular outcomes. FINDINGS TO DATE: 4423 (1740, 39.3% men) were recruited. Mean age was 52.3 years with a median BNP of 7.50 ng/L and 15.30 ng/L for men and women, respectively. 602 had a predicted 10-year risk of 10%-19.9%, with the remainder<10%. Age, female sex, ex-smoking status, lower heart rate, higher high-density lipoprotein and lower total cholesterol were independently associated with higher log10 BNP levels. Mean left ventricular mass was 129.2 g and 87.0 g in men and women, respectively. FUTURE PLANS: The TASCFORCE study is investigating the ability of a screening programme, using BNP and WBCE-MRI, at the time of enrolment, to evaluate prediction of CVD in a population at low/intermediate risk. Blood stored for future biomarker analyses will allow testing/development of novel biomarkers. We believe this could be a new UK Framingham study allowing study for many years to come. CLINICAL TRIAL REGISTRATION: ISRCTN38976321.


Assuntos
Doenças Cardiovasculares , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Peptídeo Natriurético Encefálico , Gadolínio , Meios de Contraste , Fatores de Risco , Fatores de Risco de Doenças Cardíacas , Biomarcadores , Colesterol , Lipoproteínas HDL
8.
Sci Rep ; 12(1): 8699, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35610505

RESUMO

Administration of therapeutic antibodies can elicit adverse immune responses in patients through the generation of anti-drug antibodies that, in turn, reduce the efficacy of the therapeutic. Removal of foreign amino acid content by humanization can lower the immunogenic risk of the therapeutic mAb. We previously developed the ultra-humanization technology "Augmented Binary Substitution" (ABS) which enables single-step CDR germlining of antibodies. The application of ABS to a chicken anti-pTau antibody generated an ultra-humanized variant, anti-pTau C21-ABS, with increased human amino acid content in the CDRs and reduced in-silico predicted immunogenicity risk. Here, we report the high-resolution crystal structure of anti-pTau C21-ABS Fab in complex with the pTau peptide (7KQK). This study examines how ultra-humanization, via CDR germlining, is facilitated while maintaining near-identical antigen affinity (within 1.6-fold). The co-complex structure reveals that the ABS molecule targets the same antigenic epitope, accommodated by structurally-similar changes in the paratope. These findings confirm that ABS enables the germlining of amino acids within CDRs by exploiting CDR plasticity, to reduce non-human amino acid CDR content, with few alterations to the overall mechanism of binding.


Assuntos
Anticorpos , Células Germinativas , Sequência de Aminoácidos , Aminoácidos , Sítios de Ligação de Anticorpos , Humanos , Imidazóis , Sulfonamidas , Tiofenos
9.
PNAS Nexus ; 1(5): pgac263, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36712347

RESUMO

Screening amino acid sequence space via experiments to discover peptides that self-assemble into amyloid fibrils is challenging. We have developed a computational peptide assembly design (PepAD) algorithm that enables the discovery of amyloid-forming peptides. Discontinuous molecular dynamics (DMD) simulation with the PRIME20 force field combined with the FoldAmyloid tool is used to examine the fibrilization kinetics of PepAD-generated peptides. PepAD screening of ∼10,000 7-mer peptides resulted in twelve top-scoring peptides with two distinct hydration properties. Our studies revealed that eight of the twelve in silico discovered peptides spontaneously form amyloid fibrils in the DMD simulations and that all eight have at least five residues that the FoldAmyloid tool classifies as being aggregation-prone. Based on these observations, we re-examined the PepAD-generated peptides in the sequence pool returned by PepAD and extracted five sequence patterns as well as associated sequence signatures for the 7-mer amyloid-forming peptides. Experimental results from Fourier transform infrared spectroscopy (FTIR), thioflavin T (ThT) fluorescence, circular dichroism (CD), and transmission electron microscopy (TEM) indicate that all the peptides predicted to assemble in silico assemble into antiparallel ß-sheet nanofibers in a concentration-dependent manner. This is the first attempt to use a computational approach to search for amyloid-forming peptides based on customized settings. Our efforts facilitate the identification of ß-sheet-based self-assembling peptides, and contribute insights towards answering a fundamental scientific question: "What does it take, sequence-wise, for a peptide to self-assemble?".

10.
iScience ; 24(6): 102554, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34189431

RESUMO

Growth differentiation factor 15 (GDF15) causes anorexia and weight loss in animal models, and higher circulating levels are associated with cachexia and reduced survival in cancer and other chronic diseases such as sepsis. To investigate the role of sepsis-induced GDF15, we examined whether GDF15 neutralization via a validated and highly potent monoclonal antibody, mAB2, modulates lipopolysaccharide (LPS)-induced anorexia, weight loss, and mortality in rodents. LPS injection transiently increased circulating GDF15 in wild-type mice, decreased food intake and body weight, and increased illness behavior and mortality at a high dose. GDF15 neutralization with mAB2 did not prevent or exacerbate any of the effects of LPS. Similarly, in GDF15 knockout mice, the LPS effect on appetite and survival was comparable with that observed in wild-type controls. Therefore, effective inhibition of circulating active GDF15 via an antibody or via gene knockout demonstrated that survival in the LPS acute inflammation model was independent of GDF15.

11.
MAbs ; 13(1): 1883239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33557673

RESUMO

Despite substantial technological advances in antibody library and display platform development, the number of approved biotherapeutics from displayed libraries remains limited. In vivo, 20-50% of peripheral B cells undergo a process of receptor editing, which modifies the variable and junctional regions of light chains to delete auto-reactive clones. However, in vitro antibody evolution relies primarily on interaction with antigen, with no in-built checkpoints to ensure that the selected antibodies have not acquired additional specificities or biophysical liabilities during the optimization process. We had previously observed an enrichment of positive charge in the complementarity-determining regions of an anti-IL-21 R antibody during affinity optimization, which correlated with more potent IL-21 neutralization, but poor in vivo pharmacokinetics (PK). There is an emerging body of data that has correlated antibody nonspecificity with poor PK in vivo, and established a series of screening assays that are predictive of this behavior. In this study we revisit the challenge of developing an anti-IL-21 R antibody that can effectively compete with IL-21 for its highly negatively charged paratope while maintaining favorable biophysical properties. In vitro deselection methods that included an excess of negatively charged membrane preparations, or deoxyribonucleic acid, during phage selection of optimization libraries were unsuccessful in avoiding enrichment of highly charged, nonspecific antibody variants. However, a combination of structure-guided rational library design, next-generation sequencing of library outputs and application of linear regression models resulted in the identification of an antibody that maintained high affinity for IL-21 R and exhibited a desirable stability and biophysical profile.


Assuntos
Anticorpos Neutralizantes/farmacologia , Desenho de Fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Subunidade alfa de Receptor de Interleucina-21/antagonistas & inibidores , Mutagênese , Engenharia de Proteínas , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/metabolismo , Especificidade de Anticorpos , Desenho Assistido por Computador , Estabilidade de Medicamentos , Células HEK293 , Humanos , Subunidade alfa de Receptor de Interleucina-21/imunologia , Subunidade alfa de Receptor de Interleucina-21/metabolismo , Conformação Proteica , Estabilidade Proteica , Relação Estrutura-Atividade
12.
Cell Metab ; 32(6): 938-950.e6, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33207247

RESUMO

Platinum-based cancer therapy is restricted by dose-limiting side effects and is associated with elevation of growth differentiation factor 15 (GDF-15). But whether this elevation contributes to such side effects has been unclear. Here, we explored the effects of GDF-15 blockade on platinum-based chemotherapy-induced emesis, anorexia, and weight loss in mice and/or nonhuman primate models. We found that circulating GDF-15 is higher in subjects with cancer receiving platinum-based chemotherapy and is positively associated with weight loss in colorectal cancer (NCT00609622). Further, chemotherapy agents associated with high clinical emetic score induce circulating GDF-15 and weight loss in mice. Platinum-based treatment-induced anorexia and weight loss are attenuated in GDF-15 knockout mice, while GDF-15 neutralization with the monoclonal antibody mAB1 improves survival. In nonhuman primates, mAB1 treatment attenuates anorexia and emesis. These results suggest that GDF-15 neutralization is a potential therapeutic approach to alleviate chemotherapy-induced side effects and improve the quality of life.


Assuntos
Anorexia/induzido quimicamente , Antineoplásicos/efeitos adversos , Fator 15 de Diferenciação de Crescimento/fisiologia , Neoplasias/terapia , Platina/efeitos adversos , Vômito/induzido quimicamente , Animais , Feminino , Humanos , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos SCID , Redução de Peso
13.
J Thromb Haemost ; 18(6): 1278-1290, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32108991

RESUMO

BACKGROUND: Previous studies have demonstrated that the A1A2A3 domains of von Willebrand factor (VWF) play a key role in regulating macrophage-mediated clearance in vivo. In particular, the A1-domain has been shown to modulate interaction with macrophage low-density lipoprotein receptor-related protein-1 (LRP1) clearance receptor. Furthermore, N-linked glycans within the A2-domain have been shown to protect VWF against premature LRP1-mediated clearance. Importantly, however, the specific regions within A1A2A3 that enable macrophage binding have not been defined. OBJECTIVE AND METHODS: To address this, we utilized site-directed PEGylation and introduced novel targeted N-linked glycosylation within A1A2A3-VWF and subsequently examined VWF clearance. RESULTS: Conjugation with a 40-kDa polyethylene glycol (PEG) moiety significantly extended the half-life of A1A2A3-VWF in VWF-/- mice in a site-specific manner. For example, PEGylation at specific sites within the A1-domain (S1286) and A3-domain (V1803, S1807) attenuated VWF clearance in vivo, compared to wild-type A1A2A3-VWF. Furthermore, PEGylation at these specific sites ablated binding to differentiated THP-1 macrophages and LRP1 cluster II and cluster IV in-vitro. Conversely, PEGylation at other positions (Q1353-A1-domain and M1545-A2-domain) had limited effects on VWF clearance or binding to LRP1.Novel N-linked glycan chains were introduced at N1803 and N1807 in the A3-domain. In contrast to PEGylation at these sites, no significant extension in half-life was observed with these N-glycan variants. CONCLUSIONS: These novel data demonstrate that site specific PEGylation but not site specific N-glycosylation modifies LRP1-dependent uptake of the A1A2A3-VWF by macrophages. This suggests that PEGylation, within the A1- and A3-domains in particular, may be used to attenuate LRP1-mediated clearance of VWF.


Assuntos
Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Fator de von Willebrand , Animais , Glicosilação , Cinética , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Camundongos , Polissacarídeos , Ligação Proteica , Fator de von Willebrand/metabolismo
14.
Blood ; 135(8): 547-557, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-31899794

RESUMO

Erythroferrone (ERFE) is produced by erythroblasts in response to erythropoietin (EPO) and acts in the liver to prevent hepcidin stimulation by BMP6. Hepcidin suppression allows for the mobilization of iron to the bone marrow for the production of red blood cells. Aberrantly high circulating ERFE in conditions of stress erythropoiesis, such as in patients with ß-thalassemia, promotes the tissue iron accumulation that substantially contributes to morbidity in these patients. Here we developed antibodies against ERFE to prevent hepcidin suppression and to correct the iron loading phenotype in a mouse model of ß-thalassemia [Hbb(th3/+) mice] and used these antibodies as tools to further characterize ERFE's mechanism of action. We show that ERFE binds to BMP6 with nanomolar affinity and binds BMP2 and BMP4 with somewhat weaker affinities. We found that BMP6 binds the N-terminal domain of ERFE, and a polypeptide derived from the N terminus of ERFE was sufficient to cause hepcidin suppression in Huh7 hepatoma cells and in wild-type mice. Anti-ERFE antibodies targeting the N-terminal domain prevented hepcidin suppression in ERFE-treated Huh7 cells and in EPO-treated mice. Finally, we observed a decrease in splenomegaly and serum and liver iron in anti-ERFE-treated Hbb(th3/+) mice, accompanied by an increase in red blood cells and hemoglobin and a decrease in reticulocyte counts. In summary, we show that ERFE binds BMP6 directly and with high affinity, and that antibodies targeting the N-terminal domain of ERFE that prevent ERFE-BMP6 interactions constitute a potential therapeutic tool for iron loading anemias.


Assuntos
Anticorpos Neutralizantes/uso terapêutico , Citocinas/antagonistas & inibidores , Hepcidinas/metabolismo , Proteínas Musculares/antagonistas & inibidores , Talassemia/tratamento farmacológico , Animais , Anticorpos Neutralizantes/farmacologia , Linhagem Celular , Citocinas/química , Citocinas/metabolismo , Células HEK293 , Humanos , Ferro/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Domínios Proteicos/efeitos dos fármacos , Talassemia/metabolismo
15.
J Fam Psychol ; 34(1): 79-89, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31599602

RESUMO

This study conducted a randomized trial to examine the efficacy of the Boys Town In-Home Family Services (IHFS) program for families of high-risk youth. Participants were recruited from a state helpline for families struggling with poor family functioning and child emotional or behavioral issues. Consent was obtained for 300 of which 152 were randomly assigned to participate in IHFS for 3-4 months and 148 were assigned to the services as usual comparison group. For the families in the treatment group, 18% did not participant in the intervention, and 66% of families received 20 or more service hours. Parent report data were collected at intake, post, as well 6 and 12 months after post data collection. Data were collected on constructs such as caregiver strain, family functioning, parenting, family resources, and parent report of child behavior. Piecewise analyses of the intake to post data indicated significantly greater reductions in caregiver strain for the treatment condition. Given the conservative corrections for the use of multiple tests, no other measures demonstrated significant differences. For the piecewise model of the maintenance phase, there were no significant differences between groups aside from caregiver strain that showed a significant improvement for the comparison condition. Supplementary dose-response analyses indicated that for most families there was an ideal dosage of about 25-75 hr to bring about the largest improvements in caregiver strain, parenting skills, and child behavior. (PsycINFO Database Record (c) 2020 APA, all rights reserved).


Assuntos
Cuidadores/psicologia , Terapia Familiar/métodos , Visita Domiciliar , Poder Familiar/psicologia , Pais/educação , Comportamento Problema/psicologia , Adolescente , Adulto , Cuidadores/estatística & dados numéricos , Criança , Comportamento Infantil , Família/psicologia , Feminino , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Relações Pais-Filho , Pais/psicologia
17.
J Behav Health Serv Res ; 46(2): 306-318, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29956072

RESUMO

For parents of youth with emotional and behavioral disorders, activation, or having the knowledge, skills, and confidence to access and engage in appropriate services for their children, is important for managing their child's mental health care. The Parent Activation Measure (PAM) was modified to create the Parent Patient Activation Measure-Mental Health (P-PAM-MH) to measure activation as part of a randomized controlled trial of a peer parent support intervention for parents of youth with emotional and behavioral problems. Results from this study provide initial support for use of the P-PAM-MH as a measure of activation in this population and for the reliability and validity of the measure. Implications of the findings from this study for research and practice in behavioral health are discussed.


Assuntos
Sintomas Afetivos/psicologia , Transtornos do Comportamento Infantil/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Pais/psicologia , Autocuidado , Inquéritos e Questionários/normas , Adolescente , Adulto , Idoso , Cuidadores/psicologia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Meio-Oeste dos Estados Unidos , Psicometria , Autocuidado/métodos , Autocuidado/psicologia , Apoio Social
18.
Blood ; 132(14): 1473-1477, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30097509

RESUMO

Decreased hepcidin mobilizes iron, which facilitates erythropoiesis, but excess iron is pathogenic in ß-thalassemia. Erythropoietin (EPO) enhances erythroferrone (ERFE) synthesis by erythroblasts, and ERFE suppresses hepatic hepcidin production through an unknown mechanism. The BMP/SMAD pathway in the liver is critical for hepcidin control, and we show that EPO suppressed hepcidin and other BMP target genes in vivo in a partially ERFE-dependent manner. Furthermore, recombinant ERFE suppressed the hepatic BMP/SMAD pathway independently of changes in serum and liver iron. In vitro, ERFE decreased SMAD1, SMAD5, and SMAD8 phosphorylation and inhibited expression of BMP target genes. ERFE specifically abrogated the induction of hepcidin by BMP5, BMP6, and BMP7 but had little or no effect on hepcidin induction by BMP2, BMP4, BMP9, or activin B. A neutralizing anti-ERFE antibody prevented ERFE from inhibiting hepcidin induction by BMP5, BMP6, and BMP7. Cell-free homogeneous time-resolved fluorescence assays showed that BMP5, BMP6, and BMP7 competed with anti-ERFE for binding to ERFE. We conclude that ERFE suppresses hepcidin by inhibiting hepatic BMP/SMAD signaling via preferentially impairing an evolutionarily closely related BMP subgroup of BMP5, BMP6, and BMP7. ERFE can act as a natural ligand trap generated by stimulated erythropoiesis to regulate the availability of iron.


Assuntos
Proteína Morfogenética Óssea 6/metabolismo , Citocinas/metabolismo , Hepcidinas/metabolismo , Proteínas Musculares/metabolismo , Animais , Linhagem Celular , Células Hep G2 , Humanos , Ferro/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Transdução de Sinais , Proteínas Smad/metabolismo
19.
Radiology ; 287(3): 795-804, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29714681

RESUMO

Purpose To quantify the burden and distribution of asymptomatic atherosclerosis in a population with a low to intermediate risk of cardiovascular disease. Materials and Methods Between June 2008 and February 2013, 1528 participants with 10-year risk of cardiovascular disease less than 20% were prospectively enrolled. They underwent whole-body magnetic resonance (MR) angiography at 3.0 T by using a two-injection, four-station acquisition technique. Thirty-one arterial segments were scored according to maximum stenosis. Scores were summed and normalized for the number of assessable arterial segments to provide a standardized atheroma score (SAS). Multiple linear regression was performed to assess effects of risk factors on atheroma burden. Results A total of 1513 participants (577 [37.9%] men; median age, 53.5 years; range, 40-83 years) completed the study protocol. Among 46 903 potentially analyzable segments, 46 601 (99.4%) were interpretable. Among these, 2468 segments (5%) demonstrated stenoses, of which 1649 (3.5%) showed stenosis less than 50% and 484 (1.0%) showed stenosis greater than or equal to 50%. Vascular stenoses were distributed throughout the body with no localized distribution. Seven hundred forty-seven (49.4%) participants had at least one stenotic vessel, and 408 (27.0%) participants had multiple stenotic vessels. At multivariable linear regression, SAS correlated with age (B = 3.4; 95% confidence interval: 2.61, 4.20), heart rate (B = 1.23; 95% confidence interval: 0.51, 1.95), systolic blood pressure (B = 0.02; 95% confidence interval: 0.01, 0.03), smoking status (B = 0.79; 95% confidence interval: 0.44, 1.15), and socioeconomic status (B = -0.06; 95% confidence interval: -0.10, -0.02) (P < .01 for all). Conclusion Whole-body MR angiography identifies early vascular disease at a population level. Although disease prevalence is low on a per-vessel level, vascular disease is common on a per-participant level, even in this low- to intermediate-risk cohort. © RSNA, 2018 Online supplemental material is available for this article.


Assuntos
Aterosclerose/diagnóstico por imagem , Aterosclerose/epidemiologia , Angiografia por Ressonância Magnética/métodos , Imagem Corporal Total/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Risco , Escócia/epidemiologia
20.
J Cardiovasc Magn Reson ; 20(1): 7, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29382349

RESUMO

BACKGROUND: Arteriosclerosis (arterial stiffening) is associated with future cardiovascular events, with this effect postulated to be due to its effect on cardiac afterload, atherosclerosis (plaque formation) progression or both, but with limited evidence examining these early in disease formation. The aim of the current study is to examine the association between arteriosclerosis, atherosclerosis and ventricular remodelling in a population at low-intermediate cardiovascular risk. METHODS: One thousand six hundred fifty-one subjects free of clinical cardiovascular disease and with a < 20% 10 year cardiovascular risk score underwent a cardiovascular magnetic resonance (CMR) study and whole body CMR angiogram. Arteriosclerosis was measured using total arterial compliance (TAC) - calculated as the indexed stroke volume divided by the pulse pressure. Atherosclerosis was quantified using a standardised atheroma score (SAS) which was calculated by scoring 30 arterial segments within the body based on the degree of stenosis, summating these scores and normalising it to the number of assessable segments. Left ventricular remodelling was measured using left ventricular mass to volume ratio (LVMVR). RESULTS: One thousand five hundred fifteen (38% male, 53.8 ± 8.2 years old) completed the study. On univariate analysis TAC was associated with SAS but this was lost after accounting for cardiovascular risk factors in both males (B = - 0.001 (- 0.004-0.002),p = 0.62) and females (B = 0.000(95%CI -0.002--0.002),p = 0.78). In contrast compliance correlated with LVMVR after accounting for cardiovascular risk factors (B = - 0.12(95%CI -0.16--0.091),p < 0.001 in males; B = - 0.12(95%CI -0.15--0.086),p < 0.001 in females). CONCLUSION: Systemic arteriosclerosis is associated with left ventricular remodelling but not atherosclerosis. Future efforts in cardiovascular risk prevention should thus seek to address both arteriosclerosis and atherosclerosis individually.


Assuntos
Arteriosclerose/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Angiografia por Ressonância Magnética , Imagem Cinética por Ressonância Magnética , Doença Arterial Periférica/diagnóstico por imagem , Rigidez Vascular , Função Ventricular Esquerda , Remodelação Ventricular , Arteriosclerose/fisiopatologia , Estudos de Casos e Controles , Feminino , Cardiopatias/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/fisiopatologia , Placa Aterosclerótica , Valor Preditivo dos Testes , Prognóstico , Imagem Corporal Total
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