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1.
PLoS Genet ; 20(5): e1011273, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38728357

RESUMO

Existing imaging genetics studies have been mostly limited in scope by using imaging-derived phenotypes defined by human experts. Here, leveraging new breakthroughs in self-supervised deep representation learning, we propose a new approach, image-based genome-wide association study (iGWAS), for identifying genetic factors associated with phenotypes discovered from medical images using contrastive learning. Using retinal fundus photos, our model extracts a 128-dimensional vector representing features of the retina as phenotypes. After training the model on 40,000 images from the EyePACS dataset, we generated phenotypes from 130,329 images of 65,629 British White participants in the UK Biobank. We conducted GWAS on these phenotypes and identified 14 loci with genome-wide significance (p<5×10-8 and intersection of hits from left and right eyes). We also did GWAS on the retina color, the average color of the center region of the retinal fundus photos. The GWAS of retina colors identified 34 loci, 7 are overlapping with GWAS of raw image phenotype. Our results establish the feasibility of this new framework of genomic study based on self-supervised phenotyping of medical images.


Assuntos
Fundo de Olho , Estudo de Associação Genômica Ampla , Fenótipo , Retina , Humanos , Estudo de Associação Genômica Ampla/métodos , Retina/diagnóstico por imagem , Masculino , Polimorfismo de Nucleotídeo Único , Feminino , Processamento de Imagem Assistida por Computador/métodos
2.
Sci Rep ; 14(1): 7938, 2024 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575779

RESUMO

Natural killer (NK) cells destroy tissue that have been opsonized with antibodies. Strategies to generate or identify cells with increased potency are expected to enhance NK cell-based immunotherapies. We previously generated NK cells with increased antibody-dependent cell mediated cytotoxicity (ADCC) following treatment with kifunensine, an inhibitor targeting mannosidases early in the N-glycan processing pathway. Kifunensine treatment also increased the antibody-binding affinity of Fc γ receptor IIIa/CD16a. Here we demonstrate that inhibiting NK cell N-glycan processing increased ADCC. We reduced N-glycan processing with the CRIPSR-CAS9 knockdown of MGAT1, another early-stage N-glycan processing enzyme, and showed that these cells likewise increased antibody binding affinity and ADCC. These experiments led to the observation that NK cells with diminished N-glycan processing capability also revealed a clear phenotype in flow cytometry experiments using the B73.1 and 3G8 antibodies binding two distinct CD16a epitopes. We evaluated this "affinity profiling" approach using primary NK cells and identified a distinct shift and differentiated populations by flow cytometry that correlated with increased ADCC.


Assuntos
Células Matadoras Naturais , Receptores de IgG , Humanos , Receptores de IgG/metabolismo , Citometria de Fluxo , Citotoxicidade Celular Dependente de Anticorpos , Polissacarídeos/metabolismo
3.
J Biomol NMR ; 78(2): 125-132, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38407675

RESUMO

A large proportion of human proteins contain post-translational modifications that cannot be synthesized by prokaryotes. Thus, mammalian expression systems are often employed to characterize structure/function relationships using NMR spectroscopy. Here we define the selective isotope labeling of secreted, post-translationally modified proteins using human embryonic kidney (HEK)293 cells. We determined that alpha-[15N]- atoms from 10 amino acids experience minimal metabolic scrambling (C, F, H, K, M, N, R, T, W, Y). Two more interconvert to each other (G, S). Six others experience significant scrambling (A, D, E, I, L, V). We also demonstrate that tuning culture conditions suppressed V and I scrambling. These results define expectations for 15N-labeling in HEK293 cells.


Assuntos
Aminoácidos , Marcação por Isótopo , Isótopos de Nitrogênio , Ressonância Magnética Nuclear Biomolecular , Humanos , Células HEK293 , Ressonância Magnética Nuclear Biomolecular/métodos , Aminoácidos/química , Marcação por Isótopo/métodos , Processamento de Proteína Pós-Traducional
4.
Trends Ecol Evol ; 39(2): 188-198, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37802667

RESUMO

Color signals which mediate behavioral interactions across taxa and contexts are often thought of as color 'patches' - parts of an animal that appear colorful compared to other parts of that animal. Color patches, however, cannot be considered in isolation because how a color is perceived depends on its visual background. This is of special relevance to the function and evolution of signals because backgrounds give rise to a fundamental tradeoff between color signal detectability and discriminability: as its contrast with the background increases, a color patch becomes more detectable, but discriminating variation in that color becomes more difficult. Thus, the signal function of color patches can only be fully understood by considering patch and background together as an integrated whole.


Assuntos
Comportamento Predatório , Animais , Cor
5.
J Biomol NMR ; 78(1): 9-18, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37989910

RESUMO

Despite the prevalence and importance of glycoproteins in human biology, methods for isotope labeling suffer significant limitations. Common prokaryotic platforms do not produce mammalian post-translation modifications that are essential to the function of many human glycoproteins, including immunoglobulin G1 (IgG1). Mammalian expression systems require complex media and thus introduce significant costs to achieve uniform labeling. Expression with Pichia is available, though expertise and equipment requirements surpass E. coli culture. We developed a system utilizing Saccharomyces cerevisiae, [13C]-glucose, and [15N]-ammonium chloride with complexity comparable to E. coli. Here we report two vectors for expressing the crystallizable fragment (Fc) of IgG1 for secretion into the culture medium, utilizing the ADH2 or DDI2 promoters. We also report a strategy to optimize the expression yield using orthogonal Taguchi arrays. Lastly, we developed two different media formulations, a standard medium which provides 86-92% 15N and 30% 13C incorporation into the polypeptide, or a rich medium which provides 98% 15N and 95% 13C incorporation as determined by mass spectrometry. This advance represents an expression and optimization strategy accessible to experimenters with the capability to grow and produce proteins for NMR-based experiments using E. coli.


Assuntos
Escherichia coli , Saccharomyces cerevisiae , Animais , Humanos , Ressonância Magnética Nuclear Biomolecular/métodos , Glicoproteínas/química , Fragmentos Fc das Imunoglobulinas/química , Imunoglobulina G/química , Mamíferos
6.
Am J Cardiol ; 205: 445-450, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37666016

RESUMO

Atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF) are frequent co-morbid conditions. In patients with symptomatic AF and preserved left ventricular ejection fraction the clinical diagnosis of HFpEF may be difficult, as history, examination, and echocardiography are not sensitive or specific. This study sought to assess the prevalence of HFpEF in patients undergoing AF ablation utilizing resting and post-tachycardia pacing left atrial pressure (LAP) measurements. This retrospective cohort study consisted of consecutive patients with symptomatic AF and preserved left ventricular ejection fraction who had invasive hemodynamic assessment (IHA) of LAP under resting and post-tachycardia pacing conditions while undergoing AF ablation from 2020 to 2022 at a tertiary care academic medical center. Elevated LAP was defined as ≥15 mm Hg at rest and ≥15 mm Hg post-tachycardia pacing. Patients were stratified into 3 groups: (1) normal resting and post-tachycardia pacing LAP (control group), (2) elevated resting LAP (apparent HFpEF), (3) normal resting but elevated post-tachycardia pacing LAP (occult HFpEF). A total of 78 patients were included with age 64.6 ± 9.1 years, 28 (36%) female, body mass index 33.3 ± 6.5 kg/m2, 5 (6%) paroxysmal and 73 (94%) persistent AF, and CHA2DS2-VASc 3.0 ± 1.5. IHA categorized 31 (40%), 32 (41%), and 15 patients (19%) into groups 1, 2, and 3 respectively. Notably, while only 9 patients (12%) were diagnosed with HFpEF based on clinical evaluation, 47 patients (60%) were diagnosed by IHA. IHA in patients undergoing AF ablation suggests a high prevalence of clinically undiagnosed HFpEF through a novel methodology measuring resting and post-tachycardia pacing LAP.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/cirurgia , Volume Sistólico , Pressão Atrial , Insuficiência Cardíaca/epidemiologia , Prevalência , Estudos Retrospectivos , Função Ventricular Esquerda , Taquicardia
7.
Cornea ; 42(10): 1301-1305, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37404102

RESUMO

PURPOSE: The purpose of this study was to describe the management of a case of recurrent scleritis and Acanthamoeba -positive scleral abscess in a patient after the use of miltefosine for recalcitrant Acanthamoeba keratitis. METHODS: This is a case study. RESULTS: In this study, we report a case of advanced Acanthamoeba keratitis with resultant corneal perforation with therapeutic keratoplasty and associated scleritis who later developed a scleral abscess after treatment with oral miltefosine. The scleral abscess was positive for Acanthamoeba cysts and trophozoites, and after treatment for an additional several months, the patient had complete resolution of her disease. CONCLUSIONS: Acanthamoeba scleritis is a rare complication associated with Acanthamoeba keratitis. It has traditionally been treated as an immune reaction and associated inflammation, especially with the use of miltefosine. Management can require a multitude of different approaches, and in this situation, it has been demonstrated that scleritis can be infectious and that conservative management can be effective.


Assuntos
Ceratite por Acanthamoeba , Acanthamoeba , Doenças da Esclera , Esclerite , Humanos , Feminino , Ceratite por Acanthamoeba/tratamento farmacológico , Esclerite/complicações , Abscesso
8.
Cell Rep ; 42(6): 112596, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37269288

RESUMO

Neural progenitor cells lengthen their cell cycle to prime themselves for differentiation as development proceeds. It is currently not clear how they counter this lengthening and avoid being halted in the cell cycle. We show that N6-methyladenosine (m6A) methylation of cell-cycle-related mRNAs ensures the proper cell-cycle progression of late-born retinal progenitor cells (RPCs), which are born toward the end of retinogenesis and have long cell-cycle length. Conditional deletion of Mettl14, which is required for depositing m6A, led to delayed cell-cycle exit of late-born RPCs but has no effect on retinal development prior to birth. m6A sequencing and single-cell transcriptomics revealed that mRNAs involved in elongating the cell cycle were highly enriched for m6A, which could target them for degradation and guarantee proper cell-cycle progression. In addition, we identified Zfp292 as a target of m6A and potent inhibitor of RPC cell-cycle progression.


Assuntos
Células-Tronco Neurais , Retina , Retina/metabolismo , Diferenciação Celular , Divisão Celular , Organogênese
9.
Am J Ophthalmol Case Rep ; 32: 101905, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38161516

RESUMO

Purpose: To report a unique case of bilateral punctate keratitis consistent with hurricane keratopathy during apremilast therapy. Observations: A 49-year-old female presented with severe, painful, bilateral, punctate keratitis following five months of apremilast therapy. The past ocular history was noncontributory. The past medical history included psoriasis refractory to topical corticosteroids. The patient subsequently received systemic apremilast therapy and noted improvement in her psoriatic rash. Five months later the patient presented to an outside eye care provider complaining of three weeks of progressive photophobia associated with pain and redness in both eyes. On examination, the patient had decreased visual acuity with diffuse conjunctival injection and punctate epithelial erosions in a whorl-like pattern in both eyes. The remainder of the ophthalmic exam was unremarkable. The patient was started on topical moxifloxacin drops, erythromycin ointment, and preservative free artificial tears, but did not improve. Apremilast was then discontinued and topical prednisolone was added once per day. Ten weeks after discontinuation of apremilast and topical steroid therapy, the patient had recovered normal vision with an intact and normal corneal epithelium. Conclusions and Importance: This is the first case report of cornea epithelial keratitis resembling hurricane keratopathy associated with apremilast treatment and should be recognized as a possible side effect of therapy with this class of drug.

10.
Nanoscale Horiz ; 8(1): 95-107, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36426604

RESUMO

Over the last few years it has been understood that the interface between living cells and the underlying materials can be a powerful tool to manipulate cell functions. In this study, we explore the hypothesis that the electrical cell/material interface can regulate the differentiation of cancer stem-like cells (CSCs). Electrospun polymer fibres, either polyamide 66 or poly(lactic acid), with embedded graphene nanoplatelets (GnPs), have been fabricated as CSC scaffolds, providing both the 3D microenvironment and a suitable electrical environment favorable for CSCs adhesion, growth and differentiation. We have investigated the impact of these scaffolds on the morphological, immunostaining and electrophysiological properties of CSCs extracted from human glioblastoma multiform (GBM) tumor cell line. Our data provide evidence in favor of the ability of GnP-incorporating scaffolds to promote CSC differentiation to the glial phenotype. Numerical simulations support the hypothesis that the electrical interface promotes the hyperpolarization of the cell membrane potential, thus triggering the CSC differentiation. We propose that the electrical cell/material interface can regulate endogenous bioelectrical cues, through the membrane potential manipulation, resulting in the differentiation of CSCs. Material-induced differentiation of stem cells and particularly of CSCs, can open new horizons in tissue engineering and new approaches to cancer treatment, especially GBM.


Assuntos
Glioblastoma , Humanos , Eletricidade Estática , Engenharia Tecidual/métodos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Diferenciação Celular , Microambiente Tumoral
11.
Risk Anal ; 2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36115696

RESUMO

Upon shutting down operations in early 2020 due to the COVID-19 pandemic, the movie industry assembled teams of experts to help develop guidelines for returning to operation. It resulted in a joint report, The Safe Way Forward, which was created in consultation with union members and provided the basis for negotiations with the studios. A centerpiece of the report was a set of heatmaps displaying SARS-CoV-2 risks for a shoot, as a function of testing rate, community infection prevalence, community transmission rate (R0), and risk measure (either expected number of cases or probability of at least one case). We develop and demonstrate a methodology for evaluating such complex displays, in terms of how well they inform potential users, in this case, workers deciding whether the risks of a shoot are acceptable. We ask whether individuals making hypothetical return-to-work decisions can (a) read display entries, (b) compare display entries, and (c) make inferences based on display entries. Generally speaking, respondents recruited through the Amazon MTurk platform could interpret the display information accurately and make coherent decisions, suggesting that heatmaps can communicate complex risks to lay audiences. Although these heatmaps were created for practical, rather than theoretical, purposes, these results provide partial support for theoretical accounts of visual information processing and identify challenges in applying them to complex settings.

12.
BMC Womens Health ; 22(1): 386, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36131336

RESUMO

BACKGROUND: Digital mobile health (mHealth) applications are a popular form of prenatal education and care delivery in the U.S.; yet there are few Spanish language options for native speakers. Furthermore, existing applications do not consider cultural differences and disparities in healthcare access, including those specific to emerging Latino communities. OBJECTIVE: To adapt and translate an English-language pregnancy mobile health app to meet the language and cultural needs of Spanish-speaking Latino immigrants living in the United States. METHODS: We use a multi-step process, grounded in implementation science frameworks, to adapt and translate the contents of an existing pregnancy app. Interviews with stakeholders (n = 12) who advocate for the needs of pregnant individuals in an emerging Latino community were used to identify domains of possible disparities in access to prenatal care. We then conducted semi-structured interviews with peripartum Spanish-speaking Latino users (n = 14) to understand their perspectives within those domains. We identified a list of topics to create educational material for the modified app and implemented a systematic translation approach to ensure that the new version was acceptable for immigrants from different countries in Latin America. RESULTS: The interviews with stakeholders revealed seven critical domains that need to be addressed in an adapted prenatal app: language and communication, financial concerns, social support, immigration status, cultural differences, healthcare navigation, and connection to population-specific community resources that offer Spanish language services. The interviews with peripartum Spanish-speaking Latino women informed how the existing content in the app could be adjusted or built upon to address these issues, including providing information on accessing care offered in their native language and community support. Finally, we used a systematic approach to translate the existing application and create new content. CONCLUSION: This work illustrates a process to adapt an mHealth pregnancy app to the needs of an emerging Latino community, by incorporating culturally sensitive Spanish language content while focusing on addressing existing health disparities.


Assuntos
Idioma , Aplicativos Móveis , Feminino , Humanos , Gravidez , Hispânico ou Latino , Ciência da Implementação , Tradução , Estados Unidos
13.
J Biomol NMR ; 76(4): 95-105, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35802275

RESUMO

The predominant protein expression host for NMR spectroscopy is Escherichia coli, however, it does not synthesize appropriate post-translation modifications required for mammalian protein function and is not ideal for expressing naturally secreted proteins that occupy an oxidative environment. Mammalian expression platforms can address these limitations; however, these are not amenable to cost-effective uniform 15 N labeling resulting from highly complex growth media requirements. Yeast expression platforms combine the simplicity of bacterial expression with the capabilities of mammalian platforms, however yeasts require optimization prior to isotope labeling. Yeast expression will benefit from methods to boost protein expression levels and developing labeling conditions to facilitate growth and high isotope incorporation within the target protein. In this work, we describe a novel platform based on the yeast Saccharomyces cerevisiae that simultaneously expresses the Kar2p chaperone and protein disulfide isomerase in the ER to facilitate the expression of secreted proteins. Furthermore, we developed a growth medium for uniform 15 N labeling. We recovered 2.2 mg/L of uniformly 15 N-labeled human immunoglobulin (Ig)G1 Fc domain with 90.6% 15 N labeling. NMR spectroscopy revealed a high degree of similarity between the yeast and mammalian-expressed IgG1 Fc domains. Furthermore, we were able to map the binding interaction between IgG1 Fc and the Z domain through chemical shift perturbations. This platform represents a novel cost-effective strategy for 15 N-labeled immunoglobulin fragments.


Assuntos
Fragmentos Fc das Imunoglobulinas , Saccharomyces cerevisiae , Animais , Escherichia coli/metabolismo , Glicosilação , Humanos , Fragmentos Fc das Imunoglobulinas/química , Imunoglobulina G/química , Imunoglobulina G/metabolismo , Marcação por Isótopo/métodos , Mamíferos/metabolismo , Ressonância Magnética Nuclear Biomolecular/métodos , Saccharomyces cerevisiae/metabolismo
14.
Cureus ; 14(4): e24563, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35664402

RESUMO

Background and objective The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus that causes coronavirus disease 2019 (COVID-19) infection, with symptoms ranging from mild upper respiratory illness to multisystem organ failure, and even death. Since its discovery in December 2019, the SARS-CoV-2 virus has led to a global pandemic, rapidly spreading to countries around the world, with millions of reported deaths to date. As researchers around the world continue to analyze and interpret the data gathered regarding the novel virus, it is evident that its co-infection with various bacterial pathogens is associated with a worse overall prognosis. One such bacterial pathogen, Mycoplasma pneumoniae (M. pneumoniae), has been associated with an increase in inpatient mortality, length of hospital stay, and need for mechanical ventilation. The aim of this study was to evaluate the characteristics and outcomes of patients co-infected with SARS-CoV-2 and M. pneumoniae. We sought to determine if this co-infection led to increased incidence of ventilatory support, intensive care unit (ICU) stay, and mortality. Materials and Methods A multi-center retrospective study was conducted involving patients aged 18 years and older. We compared the incidence of in-hospital mortality, ICU stay, and mechanical ventilation support between COVID-19-positive patients with and without M. pneumoniae co-infection. Based on the collected data, a binary logistic regression model was implemented to assess the correlation between mortality and ventilatory support, while linear regression was used to study the length of stay (LOS) independent variable. Results A total of 1,208 patients with a positive SARS-CoV-2 test were identified. Among them, 604 (50%) had an M. pneumoniae co-infection. LOS (95% CI for the coefficient estimate [0.86, 1.05], p<0.001), need for mechanical ventilation (95% CI for the odds ratio [2.60, 6.02], p<0.001), and inpatient mortality (95% CI for the odds ratio [1.43, 2.97], p<0.001) among those co-infected were significantly higher compared to COVID-19 patients without concomitant M. pneumoniae infection. Conclusion COVID-19 with a concomitant M. pneumoniae infection was found to have worse outcomes and overall prognosis when compared to individuals with independent disease states. Based on retrospective data gathered from a large multicenter database, the rates of mortality, ventilatory support, and length of hospital stay were significantly worse in patients with a co-infection of SARS-CoV-2 and M. pneumoniae.

15.
Proc Biol Sci ; 289(1976): 20220756, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35673868

RESUMO

Colour signals of many animals are surrounded by a high-contrast achromatic background, but little is known about the possible function of this arrangement. For both humans and non-human animals, the background colour surrounding a colour stimulus affects the perception of that stimulus, an effect that can influence detection and discrimination of colour signals. Specifically, high colour contrast between the background and two given colour stimuli makes discrimination more difficult. However, it remains unclear how achromatic background contrast affects signal discrimination in non-human animals. Here, we test whether achromatic contrast between signal-relevant colours and an achromatic background affects the ability of zebra finches to discriminate between those colours. Using an odd-one-out paradigm and generalized linear mixed models, we found that higher achromatic contrast with the background, whether positive or negative, decreases the ability of zebra finches to discriminate between target and non-target stimuli. This effect is particularly strong when colour distances are small (less than 4 ΔS) and Michelson achromatic contrast with the background is high (greater than 0.5). We suggest that researchers should consider focal colour patches and their backgrounds as collectively comprising a signal, rather than focusing on solely the focal colour patch itself.


Assuntos
Percepção de Cores , Tentilhões , Animais , Cor
16.
Front Neurol ; 13: 887669, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677341

RESUMO

Objectives: We sought to estimate reliable change thresholds for the Montreal Cognitive Assessment (MoCA) for older adults with suspected Idiopathic Normal Pressure Hydrocephalus (iNPH). Furthermore, we aimed to determine the likelihood that shunted patients will demonstrate significant improvement on the MoCA, and to identify possible predictors of this improvement. Methods: Patients (N = 224) presenting with symptoms of iNPH were given a MoCA assessment at their first clinic visit, and also before and after tap test (TT) or extended lumbar drainage (ELD). Patients who were determined to be good candidates for shunts (N = 71, 31.7%) took another MoCA assessment following shunt insertion. Reliable change thresholds for MoCA were derived using baseline visit to pre-TT/ELD assessment using nine different methodologies. Baseline characteristics of patients whose post-shunt MoCA did and did not exceed the reliable change threshold were compared. Results: All nine of reliable change methods indicated that a 5-point increase in MoCA would be reliable for patients with a baseline MoCA from 16 to 22 (38.4% of patients). Furthermore, a majority of reliable change methods indicated that a 5-point increase in MoCA would be reliable for patients with a baseline MoCA from 14 to 25. Reliable change thresholds varied across methods from 4 to 7 points for patients outside of this range. 10.1% had at least a 5-point increase from baseline to post-TT/ELD. Compared to patients who did not receive a shunt, patients who received a shunt did not have lower average MoCA at baseline (p = 0.88) or have better improvement in MoCA scores after the tap test (p = 0.17). Among shunted patients, 23.4% improved by at least 5 points on the MoCA from baseline to post-shunt. Time since onset of memory problems and post-TT/ELD gait function were the only clinical factors significantly associated with having a reliable change in MoCA after shunt insertion (p = 0.019; p = 0.03, respectively). Conclusions: In patients with iNPH, clinicians could consider using a threshold of 5 points for determining whether iNPH-symptomatic patients have experienced cognitive benefits from cerebrospinal fluid drainage at an individual level. However, a reliable change cannot be detected for patients with a baseline MoCA of 26 or greater, necessitating a different cognitive assessment tool for these patients.

17.
Clin Trials ; 19(3): 326-336, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35510559

RESUMO

BACKGROUND/AIMS: The quality of the evidence used to evaluate a drug's safety and efficacy depends, in part, on how well participants adhere to the prescribed drug-taking regime. There are multiple approaches to measure adherence in clinical trials, varying in their cost and accuracy. We demonstrate a method for evaluating the cost-effectiveness of common adherence monitoring methods, considering the costs and data quality for drugs that differ in how forgiving they are of nonadherence. METHODS: We propose a simulation approach to estimate the value of evidence about adherence, considering both costs of collection and potential errors in interpreting clinical trial results. We demonstrate the approach with a simulated clinical trial of nitrendipine, a common calcium channel blocker. We consider two trial designs, one using pretrial adherence to "enrich" the trial sample and one without an enrichment strategy. We use scenarios combining high and low values of two key properties of a clinical trial: participant adherence and drug forgiveness. RESULTS: Under the conditions of these simulations, the most cost-effective adherence monitoring approach depends on both trial participant adherence and drug forgiveness. For example, the enrichment strategy is not cost-effective for the base scenario (high forgiveness and high adherence), but is for other scenarios. We also estimate the effects of evaluable patient analysis, a controversial procedure that excludes nonadherent participants from the analyses, after a trial is completed. CONCLUSIONS: Our proposed approach can guide drug regulators and developers in designing efficient clinical trials and assessing the impact of nonadherence on trial results. It can identify cost-effective adherence-monitoring methods, given available knowledge about the methods, drug, and patients' expected adherence.


Assuntos
Adesão à Medicação , Cooperação do Paciente , Análise Custo-Benefício , Humanos , Preparações Farmacêuticas
18.
Nat Cell Biol ; 24(4): 590-600, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35414015

RESUMO

Multiplexed modulation of endogenous genes is crucial for sophisticated gene therapy and cell engineering. CRISPR-Cas12a systems enable versatile multiple-genomic-loci targeting by processing numerous CRISPR RNAs (crRNAs) from a single transcript; however, their low efficiency has hindered in vivo applications. Through structure-guided protein engineering, we developed a hyper-efficient Lachnospiraceae bacterium Cas12a variant, termed hyperCas12a, with its catalytically dead version hyperdCas12a showing significantly enhanced efficacy for gene activation, particularly at low concentrations of crRNA. We demonstrate that hyperdCas12a has comparable off-target effects compared with the wild-type system and exhibits enhanced activity for gene editing and repression. Delivery of the hyperdCas12a activator and a single crRNA array simultaneously activating the endogenous Oct4, Sox2 and Klf4 genes in the retina of post-natal mice alters the differentiation of retinal progenitor cells. The hyperCas12a system offers a versatile in vivo tool for a broad range of gene-modulation and gene-therapy applications.


Assuntos
Proteínas Associadas a CRISPR , Animais , Proteínas Associadas a CRISPR/genética , Proteínas Associadas a CRISPR/metabolismo , Sistemas CRISPR-Cas , Edição de Genes , Camundongos , RNA/metabolismo
19.
Lung Cancer (Auckl) ; 13: 1-12, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35264891

RESUMO

The treatment paradigm for malignant pleural mesothelioma (MPM) has changed little in the last 18 years. Radical intent treatment, consisting of surgical resection, radiotherapy and chemotherapy, has been offered to a highly select few; however, there is little randomised evidence to validate this approach. Prior to 2020 chemotherapy with platinum and an anti-folate was the only intervention with randomised evidence to demonstrate improved overall survival (OS) in MPM. No systemic therapy had been demonstrated to improve OS in the second line setting until 2020. The publication of the Checkmate 743 trial in 2021 demonstrated a survival benefit of combination immunotherapy over standard chemotherapy in newly diagnosed patients with MPM. This finding was shortly followed by the CONFIRM trial which demonstrates a modest but significant survival benefit of second line nivolumab versus placebo in patients having previously received standard chemotherapy. The results of these trials, recent biomarker directed therapy and chemotherapy adjuncts are discussed within this review. The integration of immunotherapy for the few patients in whom radical surgical therapy is intended is currently the subject of clinical trials and offers the prospect of improving outcomes in this rare but devastating disease.

20.
J Biol Chem ; 298(4): 101674, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35148987

RESUMO

Adeno-associated viruses (AAVs) targeting specific cell types are powerful tools for studying distinct cell types in the central nervous system (CNS). Cis-regulatory modules (CRMs), e.g., enhancers, are highly cell-type-specific and can be integrated into AAVs to render cell type specificity. Chromatin accessibility has been commonly used to nominate CRMs, which have then been incorporated into AAVs and tested for cell type specificity in the CNS. However, chromatin accessibility data alone cannot accurately annotate active CRMs, as many chromatin-accessible CRMs are not active and fail to drive gene expression in vivo. Using available large-scale datasets on chromatin accessibility, such as those published by the ENCODE project, here we explored strategies to increase efficiency in identifying active CRMs for AAV-based cell-type-specific labeling and manipulation. We found that prescreening of chromatin-accessible putative CRMs based on the density of cell-type-specific transcription factor binding sites (TFBSs) can significantly increase efficiency in identifying active CRMs. In addition, generation of synthetic CRMs by stitching chromatin-accessible regions flanking cell-type-specific genes can render cell type specificity in many cases. Using these straightforward strategies, we generated AAVs that can target the extensively studied interneuron and glial cell types in the retina and brain. Both strategies utilize available genomic datasets and can be employed to generate AAVs targeting specific cell types in CNS without conducting comprehensive screening and sequencing experiments, making a step forward in cell-type-specific research.


Assuntos
Encéfalo , Dependovirus , Retina , Coloração e Rotulagem , Fatores de Transcrição , Animais , Sítios de Ligação , Encéfalo/citologia , Encéfalo/metabolismo , Cromatina/genética , Cromatina/metabolismo , Dependovirus/genética , Dependovirus/metabolismo , Camundongos , Retina/citologia , Retina/metabolismo , Coloração e Rotulagem/métodos , Fatores de Transcrição/metabolismo
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