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1.
Cell ; 170(2): 249-259.e25, 2017 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-28669536

RESUMO

Widespread resistance to first-line TB drugs is a major problem that will likely only be resolved through the development of new drugs with novel mechanisms of action. We have used structure-guided methods to develop a lead molecule that targets the thioesterase activity of polyketide synthase Pks13, an essential enzyme that forms mycolic acids, required for the cell wall of Mycobacterium tuberculosis. Our lead, TAM16, is a benzofuran class inhibitor of Pks13 with highly potent in vitro bactericidal activity against drug-susceptible and drug-resistant clinical isolates of M. tuberculosis. In multiple mouse models of TB infection, TAM16 showed in vivo efficacy equal to the first-line TB drug isoniazid, both as a monotherapy and in combination therapy with rifampicin. TAM16 has excellent pharmacological and safety profiles, and the frequency of resistance for TAM16 is ∼100-fold lower than INH, suggesting that it can be developed as a new antitubercular aimed at the acute infection. PAPERCLIP.


Assuntos
Antituberculosos/farmacologia , Benzofuranos/farmacologia , Desenho de Fármacos , Farmacorresistência Bacteriana , Mycobacterium tuberculosis/efeitos dos fármacos , Piperidinas/farmacologia , Tuberculose/microbiologia , Animais , Antituberculosos/química , Benzofuranos/química , Benzofuranos/farmacocinética , Linhagem Celular , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Piperidinas/química , Piperidinas/farmacocinética , Organismos Livres de Patógenos Específicos
2.
Proc Natl Acad Sci U S A ; 120(41): e2305180120, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37788314

RESUMO

Robots are notoriously difficult to design because of complex interdependencies between their physical structure, sensory and motor layouts, and behavior. Despite this, almost every detail of every robot built to date has been manually determined by a human designer after several months or years of iterative ideation, prototyping, and testing. Inspired by evolutionary design in nature, the automated design of robots using evolutionary algorithms has been attempted for two decades, but it too remains inefficient: days of supercomputing are required to design robots in simulation that, when manufactured, exhibit desired behavior. Here we show de novo optimization of a robot's structure to exhibit a desired behavior, within seconds on a single consumer-grade computer, and the manufactured robot's retention of that behavior. Unlike other gradient-based robot design methods, this algorithm does not presuppose any particular anatomical form; starting instead from a randomly-generated apodous body plan, it consistently discovers legged locomotion, the most efficient known form of terrestrial movement. If combined with automated fabrication and scaled up to more challenging tasks, this advance promises near-instantaneous design, manufacture, and deployment of unique and useful machines for medical, environmental, vehicular, and space-based tasks.

3.
J Biol Chem ; 300(3): 105747, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38354783

RESUMO

Glycosyltransferases (GT) catalyze the glycosylation of bioactive natural products, including peptides and proteins, flavonoids, and sterols, and have been extensively used as biocatalysts to generate glycosides. However, the often narrow substrate specificity of wild-type GTs requires engineering strategies to expand it. The GT-B structural family is constituted by GTs that share a highly conserved tertiary structure in which the sugar donor and acceptor substrates bind in dedicated domains. Here, we have used this selective binding feature to design an engineering process to generate chimeric glycosyltransferases that combine auto-assembled domains from two different GT-B enzymes. Our approach enabled the generation of a stable dimer with broader substrate promiscuity than the parent enzymes that were related to relaxed interactions between domains in the dimeric GT-B. Our findings provide a basis for the development of a novel class of heterodimeric GTs with improved substrate promiscuity for applications in biotechnology and natural product synthesis.


Assuntos
Biocatálise , Glicosiltransferases , Flavonoides/química , Glicosilação , Glicosiltransferases/química , Glicosiltransferases/genética , Especificidade por Substrato , Domínios Proteicos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Bioengenharia/métodos
4.
J Biol Chem ; 299(6): 104740, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37088134

RESUMO

Plexin-B1 is a receptor for the cell surface semaphorin, Sema4D. This signaling system has been implicated in a variety of human diseases, including cancer, multiple sclerosis and osteoporosis. While inhibitors of the Plexin-B1:Sema4D interaction have been previously reported, understanding their mechanism has been hindered by an incomplete structural view of Plexin-B1. In this study, we have raised and characterized a pair of nanobodies that are specific for mouse Plexin-B1 and which inhibit the binding of Sema4D to mouse Plexin-B1 and its biological activity. Structural studies of these nanobodies reveal that they inhibit the binding of Sema4D in an allosteric manner, binding to epitopes not previously reported. In addition, we report the first unbound structure of human Plexin-B1, which reveals that Plexin-B1 undergoes a conformational change on Sema4D binding. These changes mirror those seen upon binding of allosteric peptide modulators, which suggests a new model for understanding Plexin-B1 signaling and provides a potential innovative route for therapeutic modulation of Plexin-B1.


Assuntos
Moléculas de Adesão Celular , Semaforinas , Anticorpos de Domínio Único , Animais , Camundongos , Receptores de Superfície Celular/metabolismo , Semaforinas/metabolismo , Transdução de Sinais , Moléculas de Adesão Celular/metabolismo
5.
J Virol ; 97(11): e0042423, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37929963

RESUMO

IMPORTANCE: SARS-CoV-2 has caused a worldwide health and economic crisis. During the course of the pandemic, genetic changes occurred in the virus, which have resulted in new properties of the virus-particularly around gains in transmission and the ability to partially evade either natural or vaccine-acquired immunity. Some of these viruses have been labeled Variants of Concern (VoCs). At the root of all VoCs are two mutations, one in the viral spike protein that has been very well characterized and the other in the virus polymerase (NSP12). This is the viral protein responsible for replicating the genome. We show that NSP12 associates with host cell proteins that act as a scaffold to facilitate the function of this protein. Furthermore, we found that different variants of NSP12 interact with host cell proteins in subtle and different ways, which affect function.


Assuntos
COVID-19 , RNA-Polimerase RNA-Dependente de Coronavírus , Proteína 2 com Domínio MARVEL , SARS-CoV-2 , Humanos , Imunidade Adaptativa , COVID-19/virologia , Citosol , Mutação , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , RNA-Polimerase RNA-Dependente de Coronavírus/genética , Proteína 2 com Domínio MARVEL/genética
6.
Environ Sci Technol ; 58(18): 8020-8031, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38629457

RESUMO

Cyanobacterial blooms introduce autochthonous dissolved organic matter (DOM) into aquatic environments, but their impact on surface water photoreactivity has not been investigated through collaborative field sampling with comparative laboratory assessments. In this work, we quantified the apparent quantum yields (Φapp,RI) of reactive intermediates (RIs), including excited triplet states of dissolved organic matter (3DOM*), singlet oxygen (1O2), and hydroxyl radicals (•OH), for whole water samples collected by citizen volunteers from more than 100 New York lakes. Multiple comparisons tests and orthogonal partial least-squares analysis identified the level of cyanobacterial chlorophyll a as a key factor in explaining the enhanced photoreactivity of whole water samples sourced from bloom-impacted lakes. Laboratory recultivation of bloom samples in bloom-free lake water demonstrated that apparent increases in Φapp,RI during cyanobacterial growth were likely driven by the production of photoreactive moieties through the heterotrophic transformation of freshly produced labile bloom exudates. Cyanobacterial proliferation also altered the energy distribution of 3DOM* and contributed to the accelerated transformation of protriptyline, a model organic micropollutant susceptible to photosensitized reactions, under simulated sunlight conditions. Overall, our study provides insights into the relationship between the photoreactivity of surface waters and the limnological characteristics and trophic state of lakes and highlights the relevance of cyanobacterial abundance in predicting the photoreactivity of bloom-impacted surface waters.


Assuntos
Cianobactérias , Lagos , Lagos/microbiologia , New York , Eutrofização , Monitoramento Ambiental
7.
Nucleic Acids Res ; 50(6): 3475-3489, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35244721

RESUMO

The SARS-CoV-2 virus has a complex transcriptome characterised by multiple, nested subgenomic RNAsused to express structural and accessory proteins. Long-read sequencing technologies such as nanopore direct RNA sequencing can recover full-length transcripts, greatly simplifying the assembly of structurally complex RNAs. However, these techniques do not detect the 5' cap, thus preventing reliable identification and quantification of full-length, coding transcript models. Here we used Nanopore ReCappable Sequencing (NRCeq), a new technique that can identify capped full-length RNAs, to assemble a complete annotation of SARS-CoV-2 sgRNAs and annotate the location of capping sites across the viral genome. We obtained robust estimates of sgRNA expression across cell lines and viral isolates and identified novel canonical and non-canonical sgRNAs, including one that uses a previously un-annotated leader-to-body junction site. The data generated in this work constitute a useful resource for the scientific community and provide important insights into the mechanisms that regulate the transcription of SARS-CoV-2 sgRNAs.


Assuntos
COVID-19 , Nanoporos , RNA Guia de Cinetoplastídeos/química , COVID-19/genética , Genoma Viral/genética , Humanos , Capuzes de RNA , RNA Viral/genética , RNA Viral/metabolismo , SARS-CoV-2/genética
8.
J Biol Chem ; 298(9): 102265, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35850304

RESUMO

Osteoporosis and multiple sclerosis are highly prevalent diseases with limited treatment options. In light of these unmet medical needs, novel therapeutic approaches are urgently sought. Previously, the activation of the transmembrane receptor Plexin-B1 by its ligand semaphorin 4D (Sema4D) has been shown to suppress bone formation and promote neuroinflammation in mice. However, it is unclear whether inhibition of this receptor-ligand interaction by an anti-Plexin-B1 antibody could represent a viable strategy against diseases related to these processes. Here, we raised and systematically characterized a monoclonal antibody directed against the extracellular domain of human Plexin-B1, which specifically blocks the binding of Sema4D to Plexin-B1. In vitro, we show that this antibody inhibits the suppressive effects of Sema4D on human osteoblast differentiation and mineralization. To test the therapeutic potential of the antibody in vivo, we generated a humanized mouse line, which expresses transgenic human Plexin-B1 instead of endogenous murine Plexin-B1. Employing these mice, we demonstrate that the anti-Plexin-B1 antibody exhibits beneficial effects in mouse models of postmenopausal osteoporosis and multiple sclerosis in vivo. In summary, our data identify an anti-Plexin-B1 antibody as a potential therapeutic agent for the treatment of osteoporosis and multiple sclerosis.


Assuntos
Anticorpos Monoclonais , Antígenos CD , Esclerose Múltipla , Proteínas do Tecido Nervoso , Osteoporose Pós-Menopausa , Receptores de Superfície Celular , Semaforinas , Animais , Anticorpos Monoclonais/uso terapêutico , Antígenos CD/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Ligantes , Camundongos , Esclerose Múltipla/terapia , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/metabolismo , Osteoporose Pós-Menopausa/terapia , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/metabolismo , Semaforinas/antagonistas & inibidores , Semaforinas/metabolismo
9.
BMC Med ; 21(1): 25, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658548

RESUMO

BACKGROUND: Predicting the likely size of future SARS-CoV-2 waves is necessary for public health planning. In England, voluntary "plan B" mitigation measures were introduced in December 2021 including increased home working and face coverings in shops but stopped short of restrictions on social contacts. The impact of voluntary risk mitigation behaviours on future SARS-CoV-2 burden is unknown. METHODS: We developed a rapid online survey of risk mitigation behaviours ahead of the winter 2021 festive period and deployed in two longitudinal cohort studies in the UK (Avon Longitudinal Study of Parents and Children (ALSPAC) and TwinsUK/COVID Symptom Study (CSS) Biobank) in December 2021. Using an individual-based, probabilistic model of COVID-19 transmission between social contacts with SARS-CoV-2 Omicron variant parameters and realistic vaccine coverage in England, we predicted the potential impact of the SARS-CoV-2 Omicron wave in England in terms of the effective reproduction number and cumulative infections, hospital admissions and deaths. Using survey results, we estimated in real-time the impact of voluntary risk mitigation behaviours on the Omicron wave in England, if implemented for the entire epidemic wave. RESULTS: Over 95% of survey respondents (NALSPAC = 2686 and NTwins = 6155) reported some risk mitigation behaviours, with vaccination and using home testing kits reported most frequently. Less than half of those respondents reported that their behaviour was due to "plan B". We estimate that without risk mitigation behaviours, the Omicron variant is consistent with an effective reproduction number between 2.5 and 3.5. Due to the reduced vaccine effectiveness against infection with the Omicron variant, our modelled estimates suggest that between 55% and 60% of the English population could be infected during the current wave, translating into between 12,000 and 46,000 cumulative deaths, depending on assumptions about severity and vaccine effectiveness. The actual number of deaths was 15,208 (26 November 2021-1 March 2022). We estimate that voluntary risk reduction measures could reduce the effective reproduction number to between 1.8 and 2.2 and reduce the cumulative number of deaths by up to 24%. CONCLUSIONS: Predicting future infection burden is affected by uncertainty in disease severity and vaccine effectiveness estimates. In addition to biological uncertainty, we show that voluntary measures substantially reduce the projected impact of the SARS-CoV-2 Omicron variant but that voluntary measures alone would be unlikely to completely control transmission.


Assuntos
COVID-19 , SARS-CoV-2 , Estados Unidos , Criança , Humanos , Estudos Longitudinais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Inglaterra/epidemiologia
10.
PLoS Pathog ; 17(11): e1009820, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34807954

RESUMO

Interferons play a critical role in regulating host immune responses to SARS-CoV-2, but the interferon (IFN)-stimulated gene (ISG) effectors that inhibit SARS-CoV-2 are not well characterized. The IFN-inducible short isoform of human nuclear receptor coactivator 7 (NCOA7) inhibits endocytic virus entry, interacts with the vacuolar ATPase, and promotes endo-lysosomal vesicle acidification and lysosomal protease activity. Here, we used ectopic expression and gene knockout to demonstrate that NCOA7 inhibits infection by SARS-CoV-2 as well as by lentivirus particles pseudotyped with SARS-CoV-2 Spike in lung epithelial cells. Infection with the highly pathogenic, SARS-CoV-1 and MERS-CoV, or seasonal, HCoV-229E and HCoV-NL63, coronavirus Spike-pseudotyped viruses was also inhibited by NCOA7. Importantly, either overexpression of TMPRSS2, which promotes plasma membrane fusion versus endosomal fusion of SARS-CoV-2, or removal of Spike's polybasic furin cleavage site rendered SARS-CoV-2 less sensitive to NCOA7 restriction. Collectively, our data indicate that furin cleavage sensitizes SARS-CoV-2 Spike to the antiviral consequences of endosomal acidification by NCOA7, and suggest that the acquisition of furin cleavage may have favoured the co-option of cell surface TMPRSS proteases as a strategy to evade the suppressive effects of IFN-induced endo-lysosomal dysregulation on virus infection.


Assuntos
COVID-19/virologia , Furina/metabolismo , Coativadores de Receptor Nuclear/metabolismo , SARS-CoV-2/fisiologia , Serina Endopeptidases/metabolismo , Linhagem Celular , Endossomos/metabolismo , Furina/genética , Expressão Gênica , Humanos , Evasão da Resposta Imune , Interferons/metabolismo , Lisossomos/enzimologia , Coativadores de Receptor Nuclear/genética , Isoformas de Proteínas , Proteólise , Serina Endopeptidases/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Pseudotipagem Viral , Internalização do Vírus
11.
Mol Psychiatry ; 27(2): 840-848, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34776512

RESUMO

One of the hallmarks of Alzheimer's disease (AD) are deposits of amyloid-beta (Aß) protein in amyloid plaques in the brain. The Aß peptide exists in several forms, including full-length Aß1-42 and Aß1-40 - and the N-truncated species, pyroglutamate Aß3-42 and Aß4-42, which appear to play a major role in neurodegeneration. We previously identified a murine antibody (TAP01), which binds specifically to soluble, non-plaque N-truncated Aß species. By solving crystal structures for TAP01 family antibodies bound to pyroglutamate Aß3-14, we identified a novel pseudo ß-hairpin structure in the N-terminal region of Aß and show that this underpins its unique binding properties. We engineered a stabilised cyclic form of Aß1-14 (N-Truncated Amyloid Peptide AntibodieS; the 'TAPAS' vaccine) and showed that this adopts the same 3-dimensional conformation as the native sequence when bound to TAP01. Active immunisation of two mouse models of AD with the TAPAS vaccine led to a striking reduction in amyloid-plaque formation, a rescue of brain glucose metabolism, a stabilisation in neuron loss, and a rescue of memory deficiencies. Treating both models with the humanised version of the TAP01 antibody had similar positive effects. Here we report the discovery of a unique conformational epitope in the N-terminal region of Aß, which offers new routes for active and passive immunisation against AD.


Assuntos
Doença de Alzheimer , Vacinas , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Anticorpos/metabolismo , Encéfalo/metabolismo , Camundongos , Fragmentos de Peptídeos/metabolismo , Placa Amiloide/metabolismo , Ácido Pirrolidonocarboxílico/metabolismo , Vacinas/metabolismo
12.
J Exp Biol ; 226(23)2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37947155

RESUMO

The vertebrate immune system provides an impressively effective defense against parasites and pathogens. However, these benefits must be balanced against a range of costly side-effects including energy loss and risks of auto-immunity. These costs might include biomechanical impairment of movement, but little is known about the intersection between immunity and biomechanics. Here, we show that a fibrosis immune response to Schistocephalus solidus infection in freshwater threespine stickleback (Gasterosteus aculeatus) has collateral effects on their locomotion. Although fibrosis is effective at reducing infection, some populations of stickleback actively suppress this immune response, possibly because the costs of fibrosis outweigh the benefits. We quantified the locomotor effects of the fibrosis immune response in the absence of parasites to investigate whether there are incidental costs of fibrosis that could help explain why some fish forego this effective defense. To do this, we induced fibrosis in stickleback and then tested their C-start escape performance. Additionally, we measured the severity of fibrosis, body stiffness and body curvature during the escape response. We were able to estimate performance costs of fibrosis by including these variables as intermediates in a structural equation model. This model revealed that among control fish without fibrosis, there is a performance cost associated with increased body stiffness. However, fish with fibrosis did not experience this cost but rather displayed increased performance with higher fibrosis severity. This result demonstrates that the adaptive landscape of immune responses can be complex with the potential for wide-reaching and unexpected fitness consequences.


Assuntos
Cestoides , Infecções por Cestoides , Doenças dos Peixes , Parasitos , Smegmamorpha , Animais , Doenças dos Peixes/parasitologia , Peixes , Cestoides/fisiologia , Imunidade , Interações Hospedeiro-Parasita , Infecções por Cestoides/parasitologia
13.
Diabetes Obes Metab ; 25(10): 3020-3029, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37435776

RESUMO

AIM: To explore whether the beneficial cardiovascular (CV) effect of sodium-glucose co-transporter-2 (SGLT-2) inhibitors is consistent with or without concurrent use of CV medications in patients with type 2 diabetes, heart failure (HF) or chronic kidney disease. METHODS: We searched Medline and Embase up to September 2022 for CV outcomes trials. The primary endpoint was the composite of cardiovascular (CV) death or hospitalization for HF. Secondary outcomes included the individual components of CV death, hospitalization for HF, death from any cause, major adverse CV events or renal events, volume depletion and hyperkalaemia. We pooled hazard ratios (HRs) and risk ratios alongside 95% confidence intervals (CIs). RESULTS: We included 12 trials comprising 83 804 patients. SGLT-2 inhibitors reduced the risk of CV death or hospitalization for HF regardless of background use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEIs/ARBs), angiotensin receptor-neprilysin inhibitors (ARNIs), b-blockers, diuretics, mineralocorticoid receptor antagonists (MRAs), or triple combination therapy of either an ACEI/ARB plus b-blocker plus MRA, or an ARNI plus b-blocker plus MRA (HRs ranged from 0.61 to 0.83; P > .1 for each subgroup interaction). Similarly, no subgroup differences were evident for most analyses for the secondary outcomes of CV death, hospitalization for HF, all-cause mortality, major adverse CV or renal events, hyperkalaemia and volume depletion rate. CONCLUSIONS: The benefit of SGLT-2 inhibitors seems to be additive to background use of CV medications in a broad population of patients. These findings should be interpreted as hypothesis generating because most of the subgroups analysed were not prespecified.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Hiperpotassemia , Inibidores do Transportador 2 de Sódio-Glicose , Simportadores , Humanos , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Antagonistas de Receptores de Angiotensina/uso terapêutico , Insuficiência Cardíaca/complicações , Simportadores/uso terapêutico , Glucose/uso terapêutico , Sódio , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/complicações
14.
15.
Nature ; 544(7650): 309-315, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28405027

RESUMO

The 2013-2016 West African epidemic caused by the Ebola virus was of unprecedented magnitude, duration and impact. Here we reconstruct the dispersal, proliferation and decline of Ebola virus throughout the region by analysing 1,610 Ebola virus genomes, which represent over 5% of the known cases. We test the association of geography, climate and demography with viral movement among administrative regions, inferring a classic 'gravity' model, with intense dispersal between larger and closer populations. Despite attenuation of international dispersal after border closures, cross-border transmission had already sown the seeds for an international epidemic, rendering these measures ineffective at curbing the epidemic. We address why the epidemic did not spread into neighbouring countries, showing that these countries were susceptible to substantial outbreaks but at lower risk of introductions. Finally, we reveal that this large epidemic was a heterogeneous and spatially dissociated collection of transmission clusters of varying size, duration and connectivity. These insights will help to inform interventions in future epidemics.


Assuntos
Ebolavirus/genética , Ebolavirus/fisiologia , Genoma Viral/genética , Doença pelo Vírus Ebola/transmissão , Doença pelo Vírus Ebola/virologia , Clima , Surtos de Doenças/estatística & dados numéricos , Ebolavirus/isolamento & purificação , Geografia , Doença pelo Vírus Ebola/epidemiologia , Humanos , Internacionalidade , Modelos Lineares , Epidemiologia Molecular , Filogenia , Viagem/legislação & jurisprudência , Viagem/estatística & dados numéricos
16.
Sensors (Basel) ; 23(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36850742

RESUMO

This paper reports a series of experimental and modeling investigations on two piezoelectric arrays made of polyvinylidene fluoride (PVDF) films. They were embedded inside rubber cylinders and used to directly measure the internal stresses generated by various external excitations applied to the top surface of the cylinder. Corresponding finite element (FE) models were established to reveal the relationship between the PVDF output and the stress field applied to it. This research improves the understanding of the output mechanism of the embedded PVDF and provides useful information for the design of PVDF sensors.

17.
Diabetologia ; 65(8): 1251-1261, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35579691

RESUMO

AIMS/HYPOTHESIS: Tirzepatide is a novel dual glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide-1 receptor agonist (GLP-1 RA) currently under review for marketing approval. Individual trials have assessed the clinical profile of tirzepatide vs different comparators. We conducted a systematic review and meta-analysis to assess the efficacy and safety of tirzepatide for type 2 diabetes. METHODS: We searched PubMed, Embase, Cochrane and ClinicalTrials.gov up until 27 October 2021 for randomised controlled trials with a duration of at least 12 weeks that compared once-weekly tirzepatide 5, 10 or 15 mg with placebo or other glucose-lowering drugs in adults with type 2 diabetes irrespective of their background glucose-lowering treatment. The primary outcome was change in HbA1c from baseline. Secondary efficacy outcomes included change in body weight, proportion of individuals reaching the HbA1c target of <53 mmol/mol (<7.0%), ≤48 mmol/mol (≤6.5%) or <39 mmol/mol (<5.7%), and proportion of individuals with body weight loss of at least 5%, 10% or 15%. Safety outcomes included hypoglycaemia, gastrointestinal adverse events, treatment discontinuation due to adverse events, serious adverse events, and mortality. We used version 2 of the Cochrane risk-of-bias tool for randomised trials to assess risk of bias for the primary outcome. RESULTS: Seven trials (6609 participants) were included. A dose-dependent superiority in lowering HbA1c was evident with all three tirzepatide doses vs all comparators, with mean differences ranging from -17.71 mmol/mol (-1.62%) to -22.35 mmol/mol (-2.06%) vs placebo, -3.22 mmol/mol (-0.29%) to -10.06 mmol/mol (-0.92%) vs GLP-1 RAs, and -7.66 mmol/mol (-0.70%) to -12.02 mmol/mol (-1.09%) vs basal insulin regimens. Tirzepatide was more efficacious in reducing body weight; reductions vs GLP-1 RAs ranged from 1.68 kg with tirzepatide 5 mg to 7.16 kg with tirzepatide 15 mg. Incidence of hypoglycaemia with tirzepatide was similar vs placebo and lower vs basal insulin. Nausea was more frequent with tirzepatide vs placebo, especially with tirzepatide 15 mg (OR 5.60 [95% CI 3.12, 10.06]), associated with higher incidence of vomiting (OR 5.50 [95% CI 2.40, 12.59]) and diarrhoea (OR 3.31 [95% CI 1.40, 7.85]). Odds of gastrointestinal events were similar between tirzepatide and GLP-1 RAs, except for diarrhoea with tirzepatide 10 mg (OR 1.51 [95% CI 1.07, 2.15]). Tirzepatide 15 mg led to higher discontinuation rate of study medication due to adverse events regardless of comparator, while all tirzepatide doses were safe in terms of serious adverse events and mortality. CONCLUSIONS/INTERPRETATION: A dose-dependent superiority on glycaemic efficacy and body weight reduction was evident with tirzepatide vs placebo, GLP-1 RAs and basal insulin. Tirzepatide did not increase the odds of hypoglycaemia but was associated with increased incidence of gastrointestinal adverse events. Study limitations include presence of statistical heterogeneity in the meta-analyses for change in HbA1c and body weight, assessment of risk of bias solely for the primary outcome, and generalisation of findings mainly to individuals who are overweight or obese and already on metformin-based background therapy. PROSPERO registration no. CRD42021283449.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemia , Insulinas , Glicemia , Peso Corporal , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diarreia/induzido quimicamente , Diarreia/complicações , Diarreia/tratamento farmacológico , Polipeptídeo Inibidor Gástrico/uso terapêutico , Peptídeo 1 Semelhante ao Glucagon/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemia/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Insulinas/uso terapêutico , Resultado do Tratamento
18.
Liver Int ; 42(7): 1503-1516, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35289467

RESUMO

BACKGROUND AND AIMS: High unit prices of treatments limit access. For epidemics like that of hepatitis C virus (HCV), reduced treatment access increases prevalence and incidence, making the infectious disease increasingly difficult to manage. The objective of the current study was to construct and test an alternative pricing model, the Payer License Agreement (PLA), and determine whether it could improve outcomes, cut costs and incentivize innovation versus the current unit-based pricing model. METHODS: We built and used computational models of hepatitis C disease progression, treatment, and pricing in historical and future scenarios and quantitatively analyzed their economic and epidemiological impact in three high-income countries. RESULTS: This study had three key results regarding HCV treatment. First, if the PLA model had been implemented when interferon-free direct-acting antiviral (DAA) combinations launched, the number of patients treated and cured would have more than doubled in the first three years, while the liver-related deaths (LRDs) would have decreased by around 40%. Second, if the PLA model had been implemented beginning in 2018, the year that several Netflix-like payment models were under implementation, the number of treated and cured patients would nearly double, and the LRDs would decline by more than 55%. Third, implementing the PLA model would result in a decline in total payer costs of more than 25%, with an increase to pharmaceutical manufacturer revenues of 10%. These results were true across the three healthcare landscapes studied, the USA, the UK and Italy, and were robust against variations to critical model parameters through sensitivity analysis. CONCLUSIONS AND RELEVANCE: These results suggest that implementation of the PLA model in high-income countries across a variety of health system contexts would improve patient outcomes at lower payer cost with more stable revenue for pharmaceutical manufacturers. Health policy-makers in high-income countries should consider the PLA model for application to more cost-effective management of HCV, and explore its application for other infectious diseases with curative therapies available now or soon.


Assuntos
Hepatite C Crônica , Hepatite C , Antivirais/uso terapêutico , Análise Custo-Benefício , Hepacivirus , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C Crônica/epidemiologia , Humanos , Preparações Farmacêuticas , Poliésteres/uso terapêutico
19.
Am J Public Health ; 112(S4): S444-S451, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35763732

RESUMO

Objectives. To create causal loop diagrams that characterize intersectional stigma experiences among Black, gay, bisexual, same gender-loving, and other men who have sex with men and to identify intervention targets to reduce stigma and increase testing and prevention access. Methods. Between January and July 2020, we conducted focus groups and in-depth interviews with 80 expert informants in New York City, which were transcribed, coded, and analyzed. These qualitative insights were developed iteratively, visualized, and validated in a causal loop diagram (CLD) using Vensim software. Results. The CLD revealed 3 key feedback loops-medical mistrust and HIV transmission, serosorting and marginalization of Black and gay individuals, and family support and internalized homophobia-that contribute to intersectional HIV and related stigmas, homophobia, and systemic racism. On the basis of these results, we designed 2 novel intervention components to integrate into an existing community-level anti-HIV stigma and homophobia intervention. Conclusions. HIV stigma, systemic racism, and homophobia work via feedback loops to reduce access to and uptake of HIV testing, prevention, and treatment. Public Health Implications. The CLD method yielded unique insights into reciprocal feedback structures that, if broken, could interrupt stigmatization and discrimination cycles that impede testing and prevention uptake. (Am J Public Health. 2022;112(S4):S444-S451. https://doi.org/10.2105/AJPH.2022.306725).


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Infecções por HIV/prevenção & controle , Seleção por Sorologia para HIV , Homossexualidade Masculina , Humanos , Masculino , Cidade de Nova Iorque , Confiança
20.
Diabetes Obes Metab ; 24(1): 106-114, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34545668

RESUMO

AIM: To assess the efficacy and safety of sotagliflozin in patients with type 2 diabetes. METHODS: We searched Medline, Embase, the Cochrane Library, and grey literature sources up to August 2021 for randomized controlled trials (RCTs) that compared sotagliflozin with placebo or other antidiabetic agents in patients with type 2 diabetes. Our primary outcome was change in HbA1c from baseline. We additionally assessed three secondary efficacy and 15 safety outcomes. We synthesized data using weighted mean differences (WMDs) and odds ratios (ORs), along with 95% confidence intervals (CIs). RESULTS: We included 11 RCTs comprising 16 411 subjects in the meta-analysis. Compared with placebo, sotagliflozin reduced HbA1c (WMD -0.42%, 95% CI -0.56 to -0.29), body weight (WMD -1.33 kg, 95% CI -1.57 to -1.09), and systolic blood pressure (WMD -2.44 mmHg, 95% CI -2.81 to -2.07). No difference was evident against other active comparators. Sotagliflozin reduced myocardial infarction (OR 0.72, 95% CI 0.54 to 0.97) and heart failure (OR 0.68, 95% CI 0.58 to 0.79) compared with placebo, and had a neutral effect on all-cause mortality, cardiovascular mortality, and stroke. Treatment with sotagliflozin was safe regarding the incidence of serious adverse events, hypoglycaemia, and diabetic ketoacidosis. Nevertheless, it was associated with an increased incidence of diarrhoea, genital infections, and volume depletion events. CONCLUSIONS: Sotagliflozin reduces blood glucose, body weight, and systolic blood pressure, and demonstrates a beneficial effect on heart failure and myocardial infarction. Its overall safety profile is comparable with other sodium-glucose co-transporter-2 inhibitors.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores do Transportador 2 de Sódio-Glicose , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glicosídeos/efeitos adversos , Humanos , Hipoglicemiantes/efeitos adversos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos
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