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Dental enamel is a principal component of teeth1, and has evolved to bear large chewing forces, resist mechanical fatigue and withstand wear over decades2. Functional impairment and loss of dental enamel, caused by developmental defects or tooth decay (caries), affect health and quality of life, with associated costs to society3. Although the past decade has seen progress in our understanding of enamel formation (amelogenesis) and the functional properties of mature enamel, attempts to repair lesions in this material or to synthesize it in vitro have had limited success4-6. This is partly due to the highly hierarchical structure of enamel and additional complexities arising from chemical gradients7-9. Here we show, using atomic-scale quantitative imaging and correlative spectroscopies, that the nanoscale crystallites of hydroxylapatite (Ca5(PO4)3(OH)), which are the fundamental building blocks of enamel, comprise two nanometric layers enriched in magnesium flanking a core rich in sodium, fluoride and carbonate ions; this sandwich core is surrounded by a shell with lower concentration of substitutional defects. A mechanical model based on density functional theory calculations and X-ray diffraction data predicts that residual stresses arise because of the chemical gradients, in agreement with preferential dissolution of the crystallite core in acidic media. Furthermore, stresses may affect the mechanical resilience of enamel. The two additional layers of hierarchy suggest a possible new model for biological control over crystal growth during amelogenesis, and hint at implications for the preservation of biomarkers during tooth development.
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Amelogênese , Esmalte Dentário/química , Ácidos/química , Cálcio/química , Carbonatos/química , Cristalização , Teoria da Densidade Funcional , Esmalte Dentário/ultraestrutura , Durapatita/química , Fluoretos/química , Humanos , Magnésio/química , Microscopia Eletrônica de Transmissão e Varredura , Sódio/química , Tomografia , Difração de Raios XRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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BACKGROUND: Despite widespread use of learning collaboratives, few randomized trials have evaluated their effectiveness as a strategy for implementing evidence based practices. This randomized trial evaluated the effectiveness of a virtual learning collaborative (VLC) in the implementation of a health promotion program for persons with serious mental illness (SMI) aimed at reducing cardiovascular risk reduction in routine mental health settings, compared to routine technical assistance (TA). METHODS: Fifty-five mental health provider organizations were recruited to participate in a Hybrid Type 3 cluster randomized implementation-effectiveness trial of the InSHAPE health promotion program for persons with SMI. Sites were stratified by size and randomized prior to implementation to an 18-month group-based VLC with monthly learning sessions or individual site TA with four scheduled conference calls over 18 months. Primary implementation and service outcomes were InSHAPE program fidelity, participation, and reach. Primary clinical outcomes were weight loss, cardiorespiratory fitness, and cardiovascular risk reduction (≥ 5% weight loss or > 50 m increase on the 6-Minute Walk Test). Program fidelity was assessed at 6, 12, and 24 months; program participation and participant-level outcomes were assessed at 3, 6, 9, and 12 months. RESULTS: VLC (N = 27) and TA (N = 28) sites were similar in organizational characteristics (all p > 0.05). At 12-month follow-up mean program fidelity score was higher in VLC compared to TA (90.5 vs. 79.1; p = 0.002), with over double the proportion with good fidelity (VLC = 73.9% vs. TA = 34.8%; p = 0.009). Over half of individuals in both VLC and TA achieved cardiovascular risk-reduction at 6-month follow-up (VLC: 51.0%; TA: 53.5%; p = 0.517) and at 12-month follow-up (62% VLC and TA; p = 0.912). At 12-month follow-up VLC compared to TA was associated with greater participation (VLC 69.5% vs. TA 56.4% attending at least 50% of sessions, p = 0.002); larger caseloads (VLC = 16 vs. TA = 11; p = 0.024); greater reach consisting of 45% greater number of participants receiving InSHAPE (VLC = 368 vs. TA = 253), and 58% greater number of participants achieving cardiovascular risk reduction (VLC = 150 vs. TA = 95). CONCLUSION: Virtual learning collaboratives compared to routine technical assistance as an implementation strategy for evidence-based health promotion promote greater intervention fidelity, greater levels of intervention participation, greater reach, and a greater number of participants achieving clinically significant risk reduction outcomes, while achieving similarly high levels of intervention effectiveness for participants who completed at least 6 months of the program.
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Educação a Distância , Saúde Mental , Humanos , Promoção da Saúde , Redução de Peso , Prática Clínica Baseada em EvidênciasRESUMO
The oncoproteins of the small DNA tumor viruses interact with a plethora of cellular regulators to commandeer control of the infected cell. During infection, adenovirus E1A deregulates cAMP signalling and repurposes it for activation of viral gene expression. We show that E1A structurally and functionally mimics a cellular A-kinase anchoring protein (AKAP). E1A interacts with and relocalizes protein kinase A (PKA) to the nucleus, likely to virus replication centres, via an interaction with the regulatory subunits of PKA. Binding to PKA requires the N-terminus of E1A, which bears striking similarity to the amphipathic α-helical domain present in cellular AKAPs. E1A also targets the same docking-dimerization domain of PKA normally bound by cellular AKAPs. In addition, the AKAP like motif within E1A could restore PKA interaction to a cellular AKAP in which its normal interaction motif was deleted. During infection, E1A successfully competes with endogenous cellular AKAPs for PKA interaction. E1A's role as a viral AKAP contributes to viral transcription, protein expression and progeny production. These data establish HAdV E1A as the first known viral AKAP. This represents a unique example of viral subversion of a crucial cellular regulatory pathway via structural mimicry of the PKA interaction domain of cellular AKAPs.
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Proteínas de Ancoragem à Quinase A/metabolismo , Proteínas E1A de Adenovirus/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Mimetismo Molecular , Proteínas de Ancoragem à Quinase A/química , Adenoviridae/química , Adenoviridae/metabolismo , Proteínas E1A de Adenovirus/química , Sequência de Aminoácidos , Linhagem Celular , Imunoprecipitação da Cromatina , Proteínas Quinases Dependentes de AMP Cíclico/química , Imunofluorescência , Técnicas de Silenciamento de Genes , Humanos , Processamento de Imagem Assistida por Computador , Imunoprecipitação , Simulação de Acoplamento Molecular , Ligação Proteica , Estrutura Secundária de Proteína , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
UNLABELLED: During infection by human adenovirus (HAdV), the proteins encoded by the early region 1A (E1A) gene bind and appropriate components of the cellular transcriptional machinery to activate the transcription of viral early genes. Previously, we identified roles for the human Bre1 (hBre1) and hPaf1 complexes in E1A-mediated transcriptional activation of HAdV early genes. Here we show that E1A binds hBre1 directly and that this complex targets the hPaf1 complex via the Rtf1 subunit. Depletion of hPaf1 reduces E1A-dependent activation of transcription from the E2e, E3, and E4 viral transcription units, and this does not result from a reduced ability of RNA polymerase II to be recruited to the promoter-proximal regions of these genes. In contrast, depletion of hPaf1 reduces the occupancy of RNA polymerase II across these transcription units. This is accompanied by reductions in the level of H3K36 trimethylation, a posttranslational histone modification associated with efficient transcriptional elongation, and the number of full-length transcripts from these genes. Together, these results indicate that E1A uses hBre1 to recruit the hPaf1 complex in order to optimally activate viral early transcription by enhancing transcriptional elongation. IMPORTANCE: This work provides the mechanism by which the hPaf1 complex contributes to E1A-dependent activation of early gene transcription. The work also demonstrates that E1A induces gene expression by stimulating transcriptional elongation, in addition to its better-characterized effects on transcriptional initiation.
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Proteínas E1A de Adenovirus/metabolismo , Adenovírus Humanos/fisiologia , Interações Hospedeiro-Patógeno , Proteínas Nucleares/metabolismo , Transcrição Gênica , Adenovírus Humanos/genética , Linhagem Celular , Células Epiteliais/virologia , Regulação Viral da Expressão Gênica , Humanos , Ligação Proteica , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Upon infection, human adenovirus (HAdV) must activate the expression of its early genes to reprogram the cellular environment to support virus replication. This activation is orchestrated in large part by the first HAdV gene expressed during infection, early region 1A (E1A). E1A binds and appropriates components of the cellular transcriptional machinery to modulate cellular gene transcription and activate viral early genes transcription. Previously, we identified hBre1/RNF20 as a target for E1A. The interaction between E1A and hBre1 antagonizes the innate antiviral response by blocking H2B monoubiquitination, a chromatin modification necessary for the interferon (IFN) response. Here, we describe a second distinct role for the interaction of E1A with hBre1 in transcriptional activation of HAdV early genes. Furthermore, we show that E1A changes the function of hBre1 from a ubiquitin ligase involved in substrate selection to a scaffold which recruits hPaf1 as a means to stimulate transcription and transcription-coupled histone modifications. By using hBre1 to recruit hPaf1, E1A is able to optimally activate viral early transcription and begin the cycle of viral replication. The ability of E1A to target hBre1 to simultaneously repress cellular IFN dependent transcription while activating viral transcription, represents an elegant example of the incredible economy of action accomplished by a viral regulatory protein through a single protein interaction.
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Infecções por Adenoviridae/metabolismo , Adenoviridae/fisiologia , Proteínas E1A de Adenovirus/metabolismo , Imunidade Inata , Proteínas Nucleares/metabolismo , Ativação Transcricional , Ubiquitina-Proteína Ligases/metabolismo , Replicação Viral/fisiologia , Infecções por Adenoviridae/genética , Infecções por Adenoviridae/imunologia , Proteínas E1A de Adenovirus/genética , Proteínas E1A de Adenovirus/imunologia , Linhagem Celular Tumoral , Histonas/genética , Histonas/imunologia , Histonas/metabolismo , Humanos , Interferons/genética , Interferons/imunologia , Interferons/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/imunologia , Processamento de Proteína Pós-Traducional/genética , Processamento de Proteína Pós-Traducional/imunologia , Fatores de Transcrição , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/imunologiaRESUMO
Metastable precursors are thought to play a major role in the ability of organisms to create mineralized tissues. Of particular interest are the hard and abrasion-resistant teeth formed by chitons, a class of rock-grazing mollusks. The formation of chiton teeth relies on the precipitation of metastable ferrihydrite (Fh) in an organic scaffold as a precursor to magnetite. Inâ vitro synthesis of Fh under physiological conditions has been challenging. Using a combination of X-ray absorption and electron paramagnetic resonance spectroscopy, we show that, prior to Fh formation in the chiton tooth, iron ions are complexed by the organic matrix. Inâ vitro experiments demonstrate that such complexes facilitate the formation of Fh under physiological conditions. These results indicate that acidic molecules may be integral to controlling Fh formation in the chiton tooth. This biological approach to polymorph selection is not limited to specialized proteins and can be expropriated using simple chemistry.
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Compostos Férricos/síntese química , Poliplacóforos/química , Animais , Espectroscopia de Ressonância de Spin Eletrônica , Espectroscopia por Absorção de Raios X , Difração de Raios XRESUMO
Early region 1A (E1A) of human adenovirus (HAdV) has been the focus of over 30 years of investigation and is required for the oncogenic capacity of HAdV in rodents. Alternative splicing of the E1A transcript generates mRNAs encoding multiple E1A proteins. The 55-residue (55R) E1A protein, which is encoded by the 9S mRNA, is particularly interesting due to the unique properties it displays relative to all other E1A isoforms. 55R E1A does not contain any of the conserved regions (CRs) present in the other E1A isoforms. The C-terminal region of the 55R E1A protein contains a unique sequence compared to all other E1A isoforms, which results from a frameshift generated by alternative splicing. The 55R E1A protein is thought to be produced preferentially at the late stages of infection. Here we report the first study to directly investigate the function of the species C HAdV 55R E1A protein during infection. Polyclonal rabbit antibodies (Abs) have been generated that are capable of immunoprecipitating HAdV-2 55R E1A. These Abs can also detect HAdV-2 55R E1A by immunoblotting and indirect immunofluorescence assay. These studies indicate that 55R E1A is expressed late and is localized to the cytoplasm and to the nucleus. 55R E1A was able to activate the expression of viral genes during infection and could also promote productive replication of species C HAdV. 55R E1A was also found to interact with the S8 component of the proteasome, and knockdown of S8 was detrimental to viral replication dependent on 55R E1A.
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Proteínas E1A de Adenovirus/genética , Proteínas E1A de Adenovirus/metabolismo , Adenovírus Humanos/genética , RNA Mensageiro/química , RNA Viral/química , Adenosina Trifosfatases/metabolismo , Proteínas E1A de Adenovirus/imunologia , Adenovírus Humanos/imunologia , Sequência de Aminoácidos , Anticorpos Antivirais/imunologia , Linhagem Celular , Núcleo Celular/metabolismo , Inibição de Contato , Citoplasma/metabolismo , Regulação Viral da Expressão Gênica , Humanos , Dados de Sequência Molecular , Ligação Proteica , Transporte Proteico , Transcrição Gênica , Replicação Viral/genéticaRESUMO
During the write-up of the meeting summary reports from the 2019 dissolution similarity workshop held at the University of Maryland's Center of Excellence in Regulatory Science and Innovation (M-CERSI), several coauthors continued their discussions to develop a "best-practice" document defining the steps required to assess dissolution profiles in support of certain biowaivers and postapproval changes. In previous reports, current challenges related to dissolution profile studies were discussed such that the steps outlined in the two flow charts ("decision trees") presented here can be applied. These decision trees include both recommendations for the use of equivalence procedures between reference and test products as well as application of the dissolution safe space concept. Common approaches towards establishing dissolution safe spaces are described. This paper encourages the preparation of protocols clearly describing why and how testing is performed along with the expected pass/fail criteria prior to generating data on the materials to be evaluated. The target audience of this manuscript includes CMC regulatory scientists, laboratory analysts, as well as statisticians from industry and regulatory health agencies involved in the assessment of product quality via in vitro dissolution testing. Building upon previous publications, this manuscript provides a solution to the current ambiguity related to dissolution profile comparison. The principles outlined in this and previous manuscripts provide a basis for global regulatory alignment in the application of dissolution profile assessment to support manufacturing changes and biowaiver requests.
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SolubilidadeRESUMO
The adenovirus E1A proteins function via protein-protein interactions. By making many connections with the cellular protein network, individual modules of this virally encoded hub reprogram numerous aspects of cell function and behavior. Although many of these interactions have been thoroughly studied, those mediated by the C-terminal region of E1A are less well understood. This review focuses on how this region of E1A affects cell cycle progression, apoptosis, senescence, transformation, and conversion of cells to an epithelial state through interactions with CTBP1/2, DYRK1A/B, FOXK1/2, and importin-α. Furthermore, novel potential pathways that the C-terminus of E1A influences through these connections with the cellular interaction network are discussed.
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Proteínas E1A de Adenovirus/metabolismo , Mapeamento de Interação de Proteínas , Adenoviridae/fisiologia , Proteínas E1A de Adenovirus/química , Proteínas E1B de Adenovirus/metabolismo , Animais , Fenômenos Fisiológicos Celulares , Transformação Celular Neoplásica , Interações Hospedeiro-Patógeno , Humanos , Ligação Proteica , Domínios e Motivos de Interação entre ProteínasRESUMO
The immunologic mechanisms underlying the faster progression of hepatitis C virus (HCV) disease in the presence of human immunodeficiency virus (HIV) coinfection are not clearly understood. T-cell cross-reactivity between HCV and influenza virus-specific epitopes has been associated with rapid progression of HCV disease (S. Urbani, B. Amadei, P. Fisicaro, M. Pilli, G. Missale, A. Bertoletti, and C. Ferrari, J. Exp. Med. 201:675-680, 2005). We asked whether T-cell cross-reactivity between HCV and HIV could exist during HCV/HIV coinfection and affect pathogenesis. Our search for amino acid sequence homology between the HCV and HIV proteomes revealed two similar HLA-A2-restricted epitopes, HIV-Gag (SLYNTVATL [HIV-SL9]) and HCV-NS5b (ALYDVVSKL [HCV-AL9]). We found that 4 out of 20 HLA-A2-positive (HLA-A2(+)) HIV-infected individuals had CD8(+) T cells that recognized both the HIV-SL9 and HCV-AL9 epitopes. However, the AL9 epitope was generally shown to be a weak agonist. Although HCV-monoinfected individuals in our study did not show AL9-specific responses, we found that about half of HCV/HIV-coinfected individuals had dual responses to both epitopes. High dual T-cell recognition among coinfected subjects was usually due to separate T-cell populations targeting each epitope, as determined by pentamer staining. The one individual demonstrating cross-reactive T cells to both epitopes showed the most advanced degree of liver disease. In coinfected individuals, we observed a positive correlation between the magnitudes of T-cell responses to both the SL9 and the AL9 epitopes, which was also positively associated with the clinical parameter of liver damage. Thus, we find that HIV infection induces T cells that can cross-react to heterologous viruses or prime for T cells that are closely related in sequence. However, the induction of cross-reactive T cells may not be associated with control of disease caused by the heterologous virus. This demonstrates that degeneracy of HIV-specific T cells may play a role in the immunopathology of HCV/HIV coinfection.
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Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Produtos do Gene gag/imunologia , Infecções por HIV/complicações , Antígeno HLA-A2/metabolismo , Hepatite C/complicações , Proteínas não Estruturais Virais/imunologia , Sequência de Aminoácidos , Linfócitos T CD8-Positivos/virologia , Reações Cruzadas , Epitopos de Linfócito T/química , Epitopos de Linfócito T/genética , Produtos do Gene gag/química , Produtos do Gene gag/genética , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Antígeno HLA-A2/genética , Hepacivirus/imunologia , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Dados de Sequência Molecular , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genéticaRESUMO
This report summarizes podium presentations and breakout sessions from the second day of the 2019 M-CERSI workshop on In Vitro Dissolution Similarity Assessment in Support of Drug Product Quality: What, How, and When? Presenters from the U.S. Food and Drug Administration (FDA), Health Canada (HC), European Medicines Agency (EMA), Brazilian Health Surveillance Agency (ANVISA), and the pharmaceutical industry shared experiences/concerns with dissolution profile similarity assessment supporting minor/moderate Chemistry, Manufacturing and Control (CMC) changes. Members from regulatory agencies explained that dissolution profile similarity testing is only part of the overall assessment of the acceptability of the proposed changes; decisions are usually made based on aggregate weight of evidence. Scientific shortcomings of f2 were highlighted but no proposal on how to replace it was made. Controlling dissolution timepoint variability and application of pairwise batch-to-batch comparisons (PBC) of dissolution profiles caused considerable debate. Several industry participants suggested increased sample sizes to raise confidence in decision-making and to avoid PBC. They proposed identification of a single mathematical method with predefined acceptance criteria and suggested that dissolution timepoint selection should follow EMA and HC guidance. A majority of meeting attendees favored applying clinically relevant dissolution specifications (CRDS) and dissolution safe space to determine the impact of minor/moderate CMC changes as opposed to dissolution profile similarity assessment via statistical methods. Day 2 of the workshop highlighted the need and opportunities for global harmonization including variability, timepoint selection, role of CRDS, and statistical methods to address the ambiguity globally operating pharmaceutical companies are currently facing.
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Indústria Farmacêutica , Motivação , Humanos , Preparações Farmacêuticas , Solubilidade , Estados Unidos , United States Food and Drug AdministrationRESUMO
In yeast, many proteins are found in both the cytoplasmic and extracellular compartments, and consequently it can be difficult to distinguish nonconventional secretion from cellular leakage. Therefore, we monitored the extracellular glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity of intact cells as a specific marker for nonconventional secretion. Extracellular GAPDH activity was proportional to the number of cells assayed, increased with incubation time, and was dependent on added substrates. Preincubation of intact cells with 100 µM dithiothreitol increased the reaction rate, consistent with increased access of the enzyme after reduction of cell wall disulfide cross-links. Such treatment did not increase cell permeability to propidium iodide, in contrast to effects of higher concentrations of reducing agents. An amine-specific membrane-impermeant biotinylation reagent specifically inactivated extracellular GAPDH. The enzyme was secreted again after a 30- to 60-min lag following the inactivation, and there was no concomitant increase in propidium iodide staining. There were about 4 × 104 active GAPDH molecules per cell at steady state, and secretion studies showed replenishment to that level 1 h after inactivation. These results establish conditions for specific quantitative assays of cell wall proteins in the absence of cytoplasmic leakage and for subsequent quantification of secretion rates in intact cells.IMPORTANCE Eukaryotic cells secrete many proteins, including many proteins that do not follow the classical secretion pathway. Among these, the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is unexpectedly found in the walls of yeasts and other fungi and in extracellular space in mammalian cell cultures. It is difficult to quantify extracellular GAPDH, because leakage of just a little of the very large amount of cytoplasmic enzyme can invalidate the determinations. We used enzymatic assays of intact cells while also maintaining membrane integrity. The results lead to estimates of the amount of extracellular enzyme and its rate of secretion to the wall in intact cells. Therefore, enzyme assays under controlled conditions can be used to investigate nonconventional secretion more generally.
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Parede Celular/enzimologia , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Saccharomyces cerevisiae/metabolismo , Secreções Corporais/metabolismo , Permeabilidade da Membrana Celular , Citoplasma/enzimologia , Citometria de Fluxo , Gliceraldeído-3-Fosfato Desidrogenases/química , Saccharomyces cerevisiae/crescimento & desenvolvimentoRESUMO
Proteins are secreted from eukaryotic cells by several mechanisms besides the well-characterized classical secretory system. Proteins destined to enter the classical secretory system contain a signal peptide for translocation into the endoplasmic reticulum. However, many proteins lacking a signal peptide are secreted nonetheless. Contrary to conventional belief, these proteins are not just released as a result of membrane damage leading to cell leakage, but are actively packaged for secretion in alternative pathways. They are called unconventionally secreted proteins, and the best-characterized are from fungi and mammals. These proteins have extracellular functions including cell signaling, immune modulation, as well as moonlighting activities different from their well-described intracellular functions. Among the pathways for unconventional secretion are direct transfer across the plasma membrane, release within plasma membrane-derived microvesicles, use of elements of autophagy, or secretion from endosomal/multivesicular body-related components. We review the fungal and metazoan unconventional secretory pathways and their regulation, and propose experimental criteria to identify their mode of secretion.
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BACKGROUND: Despite widespread use of learning collaboratives in health care, few randomized trials have evaluated their effectiveness. The primary aim of this cluster randomized implementation trial is to evaluate the effectiveness of a virtual learning collaborative (VLC) in the implementation of a lifestyle intervention for persons with serious mental illness (SMI) in routine mental health settings, compared to standard individual technical assistance. METHODS: Forty-eight mental health provider organizations from across the United States will be recruited to participate in the trial. The evidence-based practice to be implemented is the InSHAPE health promotion intervention for persons with SMI. Sites will be stratified by size and randomized to receive an 18-month intensive group-based VLC with monthly learning sessions or individual technical assistance with four scheduled conference calls over 18â¯months. Sites will be enrolled in three blocks of 16 sites each. The primary outcomes are InSHAPE program participation and fidelity, and participant weight loss; secondary outcomes are program operation, program uptake, participant health behaviors of physical activity and nutrition, organizational change, and program sustainment. Implementation outcomes are measured at 3, 6, 12, 18, and 24â¯months after the program start-up. Participant-level outcomes are measured at fixed intervals every 3â¯months after each participant enrolls in the study. DISCUSSION: This study will determine whether VLCs are an effective implementation strategy among resource-limited providers when the new practice necessitates a shift in mission, scope of practice, type of services delivered, and new financing. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03891368 Registered 25 March 2019, retrospectively registered. https://clinicaltrials.gov/ct2/show/NCT03891368?term=NCT03891368&rank=1.
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Instrução por Computador/métodos , Comportamentos Relacionados com a Saúde , Educação em Saúde/métodos , Transtornos Mentais/epidemiologia , Serviços de Saúde Mental/organização & administração , Comportamento Cooperativo , Dieta , Exercício Físico , Humanos , Capacitação em Serviço , Cooperação do Paciente , Estados Unidos/epidemiologia , Redução de PesoRESUMO
This manuscript represents the perspective of the Dissolution Working Group of the International Consortium for Innovation and Quality in Pharmaceutical Development (IQ) and of two focus groups of the American Association of Pharmaceutical Scientists (AAPS): Process Analytical Technology (PAT) and In Vitro Release and Dissolution Testing (IVRDT). The intent of this manuscript is to show recent progress in the field of in vitro predictive dissolution modeling and to provide recommended general approaches to developing in vitro predictive dissolution models for both early- and late-stage formulation/process development and batch release. Different modeling approaches should be used at different stages of drug development based on product and process understanding available at those stages. Two industry case studies of current approaches used for modeling tablet dissolution are presented. These include examples of predictive model use for product development within the space explored during formulation and process optimization, as well as of dissolution models as surrogate tests in a regulatory filing. A review of an industry example of developing a dissolution model for real-time release testing (RTRt) and of academic case studies of enabling dissolution RTRt by near-infrared spectroscopy (NIRS) is also provided. These demonstrate multiple approaches for developing data-rich empirical models in the context of science- and risk-based process development to predict in vitro dissolution. Recommendations of modeling best practices are made, focused primarily on immediate-release (IR) oral delivery products for new drug applications. A general roadmap is presented for implementation of dissolution modeling for enhanced product understanding, robust control strategy, batch release testing, and flexibility toward post-approval changes.
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Química Farmacêutica/métodos , Desenvolvimento de Medicamentos/métodos , Liberação Controlada de Fármacos , Modelos Biológicos , Administração Oral , Cápsulas , ComprimidosRESUMO
This publication summarizes the proceedings and key outcomes of the first day ("Day 1") of the 3-day workshop on "Dissolution and Translational Modeling Strategies Enabling Patient-Centric Product Development." The overall aims of the workshop were to foster a productive dialog between industry and regulatory agencies and to discuss current strategies toward the development and implementation of clinically relevant dissolution specifications as an integral part of enhanced drug product understanding and effective drug product life-cycle management. The Day 1 podium presentations covered existing challenges and concerns for implementing highly valuable, yet often unique and novel experimental dissolution setups as quality control tools. In addition, several podium presentations highlighted opportunities to replace conventional dissolution testing with surrogate test methods to enable robust drug product and process understanding within the context of quality by design (QbD), new manufacturing technologies, and real-time release testing (RTRT). The topics covered on Day 1 laid the foundation for subsequent discussions which focused on the challenges related to establishing an in vitro-in vivo link and approaches for establishing clinically relevant drug product specifications which are becoming an expectation in regulatory submissions. Clarification of dissolution-related terminology used inconsistently among the scientific community, and the purpose of various testing approaches were key discussion topics of the Day 1 breakout sessions. The outcome of these discussions along with creative ways to overcome challenges related to bridging "exploratory dissolution approaches" with methods suitable for end-product control testing are captured within this report.
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Desenvolvimento de Medicamentos/métodos , Controle de Qualidade , Animais , Congressos como Assunto , Desenvolvimento de Medicamentos/normas , Humanos , SolubilidadeRESUMO
Evidence suggests that executed, imagined, and observed movements share neural substrates, however, brain activation during the performance of these three tasks has not yet been examined during lower extremity movements. Functional MRI was performed in 10 healthy right-footed participants during imagined, executed, and observed right ankle movements. Task compliance was high, confirmed via behavioral assessment and electromyographic measurements. Each task was also associated with its own profile of regional activation, however, overall, regional activation showed substantial overlap across the three lower extremity motor tasks. The findings suggest the utility of continued efforts to develop motor imagery and observation programs for improving lower extremity function in a range of clinical settings.
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Mapeamento Encefálico , Córtex Cerebral/fisiologia , Pé/fisiologia , Imagens, Psicoterapia , Destreza Motora/fisiologia , Adulto , Eletromiografia , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , MasculinoRESUMO
This article intends to summarize the current views of the IQ Consortium Dissolution Working Group, which comprises various industry companies, on the roles of dissolution testing throughout pharmaceutical product development, registration, commercialization, and beyond. Over the past 3 decades, dissolution testing has evolved from a routine and straightforward test as a component of end-product release into a comprehensive set of tools that the developer can deploy at various stages of the product life cycle. The definitions of commonly used dissolution approaches, how they relate to one another and how they may be applied in modern drug development, and life cycle management is described in this article. Specifically, this article discusses the purpose, advantages, and limitations of quality control, biorelevant, and clinically relevant dissolution methods.
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Preparações Farmacêuticas/química , Animais , Química Farmacêutica/métodos , Humanos , Controle de Qualidade , SolubilidadeRESUMO
OBJECTIVE: The purpose of this study was to evaluate health outcomes of a state-supported implementation in community mental health settings of an evidence-based lifestyle intervention for overweight and obese adults with serious mental illness. METHODS: Weight and fitness outcomes were evaluated for 122 overweight or obese adults with serious mental illness in four community mental health centers (CMHCs) that were participating in a phased statewide implementation of the In SHAPE lifestyle intervention. Six- and 12-month outcomes were compared between two CMHCs that implemented In SHAPE in the first 12 months and two CMHCs with similar characteristics that implemented In SHAPE in a subsequent phase in the statewide implementation 12 months later. RESULTS: Participants in the two In SHAPE sites (N=63 participants) lost significantly more weight (p=.003) and showed greater improvement in fitness (p=.011) compared with participants at the two usual care control sites (N=59 participants). At six months, nearly half (49%) of In SHAPE participants and at 12 months more than half (60%) of In SHAPE participants showed clinically significant cardiovascular risk reduction defined as ≥5% weight loss or improved fitness (>50 m [164 feet] increase on the six-minute walk test). The difference between the In SHAPE and control groups was not statistically significant. CONCLUSIONS: This natural experiment demonstrated promising public health benefits of a practical implementation of health promotion programming for overweight and obese adults with serious mental illness and offers a potential model for reducing risk of early mortality among individuals served by state-funded mental health centers nationwide.