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1.
Nature ; 614(7949): 653-658, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623551

RESUMO

Measuring the metallicity and carbon-to-oxygen (C/O) ratio in exoplanet atmospheres is a fundamental step towards constraining the dominant chemical processes at work and, if in equilibrium, revealing planet formation histories. Transmission spectroscopy (for example, refs. 1,2) provides the necessary means by constraining the abundances of oxygen- and carbon-bearing species; however, this requires broad wavelength coverage, moderate spectral resolution and high precision, which, together, are not achievable with previous observatories. Now that JWST has commenced science operations, we are able to observe exoplanets at previously uncharted wavelengths and spectral resolutions. Here we report time-series observations of the transiting exoplanet WASP-39b using JWST's Near InfraRed Camera (NIRCam). The long-wavelength spectroscopic and short-wavelength photometric light curves span 2.0-4.0 micrometres, exhibit minimal systematics and reveal well defined molecular absorption features in the planet's spectrum. Specifically, we detect gaseous water in the atmosphere and place an upper limit on the abundance of methane. The otherwise prominent carbon dioxide feature at 2.8 micrometres is largely masked by water. The best-fit chemical equilibrium models favour an atmospheric metallicity of 1-100-times solar (that is, an enrichment of elements heavier than helium relative to the Sun) and a substellar C/O ratio. The inferred high metallicity and low C/O ratio may indicate significant accretion of solid materials during planet formation (for example, refs. 3,4,) or disequilibrium processes in the upper atmosphere (for example, refs. 5,6).

2.
Nature ; 604(7904): 49-52, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35388193

RESUMO

Aerosols have been found to be nearly ubiquitous in substellar atmospheres1-3. The precise temperature at which these aerosols begin to form in exoplanets has yet to be observationally constrained. Theoretical models and observations of muted spectral features indicate that silicate clouds play an important role in exoplanets between at least 950 and 2,100 K (ref. 4). Some giant planets, however, are thought to be hot enough to avoid condensation altogether5,6. Here we report the near-ultraviolet transmission spectrum of the ultra-hot Jupiter WASP-178b (approximately 2,450 K), which exhibits substantial absorption. Bayesian retrievals indicate the presence of gaseous refractory species containing silicon and magnesium, which are the precursors to condensate clouds at lower temperatures. SiO, in particular, has not previously, to our knowledge, been detected in exoplanets, but the presence of SiO in WASP-178b is consistent with theoretical expectations as the dominant Si-bearing species at high temperatures. These observations allow us to re-interpret previous observations of HAT-P-41b and WASP-121b that did not consider SiO, to suggest that silicate cloud formation begins on exoplanets with equilibrium temperatures between 1,950 and 2,450 K.

3.
Nature ; 548(7665): 58-61, 2017 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-28770846

RESUMO

Infrared radiation emitted from a planet contains information about the chemical composition and vertical temperature profile of its atmosphere. If upper layers are cooler than lower layers, molecular gases will produce absorption features in the planetary thermal spectrum. Conversely, if there is a stratosphere-where temperature increases with altitude-these molecular features will be observed in emission. It has been suggested that stratospheres could form in highly irradiated exoplanets, but the extent to which this occurs is unresolved both theoretically and observationally. A previous claim for the presence of a stratosphere remains open to question, owing to the challenges posed by the highly variable host star and the low spectral resolution of the measurements. Here we report a near-infrared thermal spectrum for the ultrahot gas giant WASP-121b, which has an equilibrium temperature of approximately 2,500 kelvin. Water is resolved in emission, providing a detection of an exoplanet stratosphere at 5σ confidence. These observations imply that a substantial fraction of incident stellar radiation is retained at high altitudes in the atmosphere, possibly by absorbing chemical species such as gaseous vanadium oxide and titanium oxide.

4.
Sensors (Basel) ; 23(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36679360

RESUMO

Big data pipelines are developed to process data characterized by one or more of the three big data features, commonly known as the three Vs (volume, velocity, and variety), through a series of steps (e.g., extract, transform, and move), making the ground work for the use of advanced analytics and ML/AI techniques. Computing continuum (i.e., cloud/fog/edge) allows access to virtually infinite amount of resources, where data pipelines could be executed at scale; however, the implementation of data pipelines on the continuum is a complex task that needs to take computing resources, data transmission channels, triggers, data transfer methods, integration of message queues, etc., into account. The task becomes even more challenging when data storage is considered as part of the data pipelines. Local storage is expensive, hard to maintain, and comes with several challenges (e.g., data availability, data security, and backup). The use of cloud storage, i.e., storage-as-a-service (StaaS), instead of local storage has the potential of providing more flexibility in terms of scalability, fault tolerance, and availability. In this article, we propose a generic approach to integrate StaaS with data pipelines, i.e., computation on an on-premise server or on a specific cloud, but integration with StaaS, and develop a ranking method for available storage options based on five key parameters: cost, proximity, network performance, server-side encryption, and user weights/preferences. The evaluation carried out demonstrates the effectiveness of the proposed approach in terms of data transfer performance, utility of the individual parameters, and feasibility of dynamic selection of a storage option based on four primary user scenarios.


Assuntos
Algoritmos , Big Data , Software , Computadores , Segurança Computacional
5.
Sensors (Basel) ; 23(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36991644

RESUMO

The popularity of smart sensors and the Internet of Things (IoT) is growing in various fields and applications. Both collect and transfer data to networks. However, due to limited resources, deploying IoT in real-world applications can be challenging. Most of the algorithmic solutions proposed so far to address these challenges were based on linear interval approximations and were developed for resource-constrained microcontroller architectures, i.e., they need buffering of the sensor data and either have a runtime dependency on the segment length or require the sensor inverse response to be analytically known in advance. Our present work proposed a new algorithm for the piecewise-linear approximation of differentiable sensor characteristics with varying algebraic curvature, maintaining the low fixed computational complexity as well as reduced memory requirements, as demonstrated in a test concerning the linearization of the inverse sensor characteristic of type K thermocouple. As before, our error-minimization approach solved the two problems of finding the inverse sensor characteristic and its linearization simultaneously while minimizing the number of points needed to support the characteristic.

6.
Lupus ; 31(4): 424-432, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35238725

RESUMO

On 16 December 2020, FDA approved Benlysta® (belimumab) for both the intravenous (IV) and subcutaneous (SC) administration routes for the treatment of adult patients with active lupus nephritis (LN) who are receiving standard therapy. This approval represents the first FDA approved treatment of patients with active LN.The approved IV dosing regimen (10 mg/kg dose Q2W for three doses, then 10 mg/kg Q4W thereafter) was based on a randomized double-blind placebo controlled clinical trial in adult patients with LN. For the approval of the SC dosing regimen (400 mg dose QW for four doses, then 200 mg QW thereafter), efficacy was supported solely by pharmacokinetics (PK) modeling and simulation which estimated a matched steady state average concentration and higher trough concentrations for the SC administration route, for bridging to the efficacy of IV belimumab in adults with LN. The safety and immunogenicity profile of the SC administration route has been assessed in the SLE studies.In a population PK analysis, higher proteinuria was associated with greater belimumab clearance and lower belimumab exposure. In an exposure response analysis, the efficacy of belimumab as evaluated by renal response was mainly driven by patients with lower proteinuria at baseline regardless of other baseline characteristics (e.g. baseline renal function, renal biopsy classification), induction therapies, or belimumab exposure levels (within 10 mg/kg dosing regimen), etc. However, post hoc analyses showed that belimumab had activity in LN patients with higher proteinuria at baseline. There is no adequate information to suggest that a higher dose would provide additional benefit for patients with lower exposure (e.g. higher proteinuria).


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Farmacologia Clínica , Adulto , Anticorpos Monoclonais Humanizados , Humanos , Imunossupressores/efeitos adversos , Lúpus Eritematoso Sistêmico/induzido quimicamente , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Nefrite Lúpica/induzido quimicamente , Nefrite Lúpica/tratamento farmacológico , Resultado do Tratamento
7.
Nature ; 529(7584): 59-62, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26675732

RESUMO

Thousands of transiting exoplanets have been discovered, but spectral analysis of their atmospheres has so far been dominated by a small number of exoplanets and data spanning relatively narrow wavelength ranges (such as 1.1-1.7 micrometres). Recent studies show that some hot-Jupiter exoplanets have much weaker water absorption features in their near-infrared spectra than predicted. The low amplitude of water signatures could be explained by very low water abundances, which may be a sign that water was depleted in the protoplanetary disk at the planet's formation location, but it is unclear whether this level of depletion can actually occur. Alternatively, these weak signals could be the result of obscuration by clouds or hazes, as found in some optical spectra. Here we report results from a comparative study of ten hot Jupiters covering the wavelength range 0.3-5 micrometres, which allows us to resolve both the optical scattering and infrared molecular absorption spectroscopically. Our results reveal a diverse group of hot Jupiters that exhibit a continuum from clear to cloudy atmospheres. We find that the difference between the planetary radius measured at optical and infrared wavelengths is an effective metric for distinguishing different atmosphere types. The difference correlates with the spectral strength of water, so that strong water absorption lines are seen in clear-atmosphere planets and the weakest features are associated with clouds and hazes. This result strongly suggests that primordial water depletion during formation is unlikely and that clouds and hazes are the cause of weaker spectral signatures.


Assuntos
Atmosfera/química , Meio Ambiente Extraterreno/química , Planetas , Água/análise , Júpiter , Pressão , Espectrofotometria Infravermelho , Telescópios , Temperatura
8.
Sensors (Basel) ; 22(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35161693

RESUMO

In this work, we introduce and use an innovative approach for adaptive piecewise linear interval approximation of sensor characteristics, which are differentiable functions. The aim is to obtain a discreet type of inverse sensor characteristic, with a predefined maximum approximation error, with minimization of the number of points defining the characteristic, which in turn is related to the possibilities for using microcontrollers with limited energy and memory resources. In this context, the results from the study indicate that to overcome the problems arising from the resource constraints of smart devices, appropriate "lightweight" algorithms are needed that allow efficient connectivity and intelligent management of the measurement processes. The method has two benefits: first, low-cost microcontrollers could be used for hardware implementation of the industrial sensor devices; second, the optimal subdivision of the measurement range reduces the space in the memory of the microcontroller necessary for storage of the parameters of the linearized characteristic. Although the discussed computational examples are aimed at building adaptive approximations for temperature sensors, the algorithm can easily be extended to many other sensor types and can improve the performance of resource-constrained devices. For prescribed maximum approximation error, the inverse sensor characteristic is found directly in the linearized form. Further advantages of the proposed approach are: (i) the maximum error under linearization of the inverse sensor characteristic at all intervals, except in the general case of the last one, is the same; (ii) the approach allows non-uniform distribution of maximum approximation error, i.e., different maximum approximation errors could be assigned to particular intervals; (iii) the approach allows the application to the general type of differentiable sensor characteristics with piecewise concave/convex properties.

9.
Sensors (Basel) ; 21(24)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34960302

RESUMO

The emergence of the edge computing paradigm has shifted data processing from centralised infrastructures to heterogeneous and geographically distributed infrastructures. Therefore, data processing solutions must consider data locality to reduce the performance penalties from data transfers among remote data centres. Existing big data processing solutions provide limited support for handling data locality and are inefficient in processing small and frequent events specific to the edge environments. This article proposes a novel architecture and a proof-of-concept implementation for software container-centric big data workflow orchestration that puts data locality at the forefront. The proposed solution considers the available data locality information, leverages long-lived containers to execute workflow steps, and handles the interaction with different data sources through containers. We compare the proposed solution with Argo workflows and demonstrate a significant performance improvement in the execution speed for processing the same data units. Finally, we carry out experiments with the proposed solution under different configurations and analyze individual aspects affecting the performance of the overall solution.


Assuntos
Big Data , Biologia Computacional , Armazenamento e Recuperação da Informação , Software , Fluxo de Trabalho
10.
Molecules ; 25(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861797

RESUMO

N. glutinosa L. is a relatively less studied Nicotiana species (Solanaceae), although there are data about its importance as a model plant in viral control studies, as a gene donor in tobacco hybridization and as a source of agents with insecticidal or fungicidal effects. The biological activities of the species were associated mostly with the presence of leaf surface metabolites, in particular diterpenes and sucrose esters. The aim of this study was to identify the chemical composition of the essential oil (EO) and two aromatic extraction products (concrete and resinoid) obtained from N. glutinosa L. leaves. GC-MS analysis identified 26 components in the EO (representing 97.3% of total oil content), which contained mostly diterpene compounds with major components manool (14.2%), sclarene (8.4%) and manoyl oxide (8.1%). The number of compounds identified in the concrete was 37 (95.5% of the total content) and the major component was the diterpene alcohol sclareol (14.2%). In the resinoid, 30 volatile components (representing 95.1% of resinoid content) were identified, with major components nicotine (32.9%), α-tocopherol (8.2%), tridecanoin (6.9%), sclareol (6.9%), and solanone (6.9%). The group of bicyclic diterpenes had the largest share in the diterpene fraction of the products (57.3%, 91.7%, and 86.3%, respectively for the EO, concrete, and resinoid). Considering the abundance of sclareol in the aromatic products, the antimicrobial activity of the pure substance was determined. Sclareol was highly effective against a set of medicinally important yeasts; Candida albicans АТСС 10231, C. glabrata ATCC 90030, C. parapsilosis clinical isolate, and C. tropicalis NBIMCC 23, while being less effective against the studied Gram-positive and Gram-negative bacteria. Data from the study on N. glutinosa aromatic products composition may be of interest to the aroma industries for their possible use in perfumery and cosmetics.


Assuntos
Anti-Infecciosos , Candida albicans/crescimento & desenvolvimento , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Nicotiana/química , Óleos Voláteis , Folhas de Planta/química , Terpenos , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Terpenos/química , Terpenos/farmacologia
11.
J Allergy Clin Immunol ; 139(2): 655-666.e7, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27484038

RESUMO

BACKGROUND: The molecular and cellular pathways driving the pathogenesis of severe asthma are poorly defined. Tumor progression locus 2 (TPL-2) (COT, MAP3K8) kinase activates the MEK1/2-extracellular-signal regulated kinase 1/2 MAP kinase signaling pathway following Toll-like receptor, TNFR1, and IL-1R stimulation. OBJECTIVE: TPL-2 has been widely described as a critical regulator of inflammation, and we sought to investigate the role of TPL-2 in house dust mite (HDM)-mediated allergic airway inflammation. METHODS: A comparative analysis of wild-type and Map3k8-/- mice was conducted. Mixed bone marrow chimeras, conditional knockout mice, and adoptive transfer models were also used. Differential cell counts were performed on the bronchoalveolar lavage fluid, followed by histological analysis of lung sections. Flow cytometry and quantitative PCR was used to measure type 2 cytokines. ELISA was used to assess the production of IgE, type 2 cytokines, and Ccl24. RNA sequencing was used to characterize dendritic cell (DC) transcripts. RESULTS: TPL-2 deficiency led to exacerbated HDM-induced airway allergy, with increased airway and tissue eosinophilia, lung inflammation, and IL-4, IL-5, IL-13, and IgE production. Increased airway allergic responses in Map3k8-/- mice were not due to a cell-intrinsic role for TPL-2 in T cells, B cells, or LysM+ cells but due to a regulatory role for TPL-2 in DCs. TPL-2 inhibited Ccl24 expression in lung DCs, and blockade of Ccl24 prevented the exaggerated airway eosinophilia and lung inflammation in mice given HDM-pulsed Map3k8-/- DCs. CONCLUSIONS: TPL-2 regulates DC-derived Ccl24 production to prevent severe type 2 airway allergy in mice.


Assuntos
Asma/imunologia , Quimiocina CCL24/metabolismo , Células Dendríticas/imunologia , Eosinófilos/imunologia , Pulmão/imunologia , MAP Quinase Quinase Quinases/metabolismo , Pneumonia/imunologia , Proteínas Proto-Oncogênicas/metabolismo , Animais , Antígenos de Dermatophagoides/imunologia , Citocinas/metabolismo , Imunoglobulina E/sangue , MAP Quinase Quinase Quinases/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Proto-Oncogênicas/genética , Pyroglyphidae/imunologia , Transdução de Sinais , Células Th2/imunologia
12.
PLoS Pathog ; 11(7): e1004994, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26147567

RESUMO

Parasitic helminths establish chronic infections in mammalian hosts. Helminth/Plasmodium co-infections occur frequently in endemic areas. However, it is unclear whether Plasmodium infections compromise anti-helminth immunity, contributing to the chronicity of infection. Immunity to Plasmodium or helminths requires divergent CD4+ T cell-driven responses, dominated by IFNγ or IL-4, respectively. Recent literature has indicated that Th cells, including Th2 cells, have phenotypic plasticity with the ability to produce non-lineage associated cytokines. Whether such plasticity occurs during co-infection is unclear. In this study, we observed reduced anti-helminth Th2 cell responses and compromised anti-helminth immunity during Heligmosomoides polygyrus and Plasmodium chabaudi co-infection. Using newly established triple cytokine reporter mice (Il4gfpIfngyfpIl17aFP635), we demonstrated that Il4gfp+ Th2 cells purified from in vitro cultures or isolated ex vivo from helminth-infected mice up-regulated IFNγ following adoptive transfer into Rag1-/- mice infected with P. chabaudi. Functionally, Th2 cells that up-regulated IFNγ were transcriptionally re-wired and protected recipient mice from high parasitemia. Mechanistically, TCR stimulation and responsiveness to IL-12 and IFNγ, but not type I IFN, was required for optimal IFNγ production by Th2 cells. Finally, blockade of IL-12 and IFNγ during co-infection partially preserved anti-helminth Th2 responses. In summary, this study demonstrates that Th2 cells retain substantial plasticity with the ability to produce IFNγ during Plasmodium infection. Consequently, co-infection with Plasmodium spp. may contribute to the chronicity of helminth infection by reducing anti-helminth Th2 cells and converting them into IFNγ-secreting cells.


Assuntos
Coinfecção/imunologia , Interferon gama/metabolismo , Interleucina-12/imunologia , Malária/imunologia , Infecções por Strongylida/imunologia , Células Th2/imunologia , Transferência Adotiva , Animais , Separação Celular , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Interferon gama/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Knockout , Nematospiroides dubius/imunologia , Plasmodium chabaudi/imunologia , Reação em Cadeia da Polimerase
13.
Proc Natl Acad Sci U S A ; 109(47): 19403-7, 2012 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-23129637

RESUMO

No conventional therapy exists for salivary hypofunction in surviving head and neck cancer patients with Radiation Therapy Oncology Group late grade 2-3 toxicity. We conducted a phase I clinical trial to test the safety and biologic efficacy of serotype 5, adenoviral-mediated aquaporin-1 cDNA transfer to a single previously irradiated parotid gland in 11 subjects using an open label, single-dose, dose-escalation design (AdhAQP1 vector; four dose tiers from 4.8 × 10(7) to 5.8 × 10(9) vector particles per gland). Treated subjects were followed at scheduled intervals. Multiple safety parameters were measured and biologic efficacy was evaluated with measurements of parotid salivary flow rate. Symptoms were assessed with a visual analog scale. All subjects tolerated vector delivery and study procedures well over the 42-d study period reported. No deaths, serious adverse events, or dose-limiting toxicities occurred. Generally, few adverse events occurred, and all were considered mild or moderate. No consistent changes were found in any clinical chemistry and hematology parameters measured. Objective responses were seen in six subjects, all at doses <5.8 × 10(9) vector particles per gland. Five of these six subjects also experienced subjective improvement in xerostomia. AdhAQP1 vector delivery to a single parotid gland was safe and transfer of the hAQP1 cDNA increased parotid flow and relieved symptoms in a subset of subjects.


Assuntos
Adenoviridae/genética , Aquaporina 1/genética , Aquaporina 1/uso terapêutico , DNA Complementar/genética , Terapia Genética , Lesões por Radiação/terapia , Doenças das Glândulas Salivares/terapia , Idoso , Citratos , Gálio , Terapia Genética/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/diagnóstico por imagem , Lesões por Radiação/genética , Cintilografia , Doenças das Glândulas Salivares/diagnóstico por imagem , Doenças das Glândulas Salivares/etiologia , Doenças das Glândulas Salivares/fisiopatologia
14.
Arthritis Rheumatol ; 76(9): 1323-1333, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38622107

RESUMO

The American College of Rheumatology and the US Food and Drug Administration co-sponsored a public meeting in May 2022 about challenges in the clinical development of drugs for rheumatoid arthritis (RA) and psoriatic arthritis (PsA), focusing on innovative clinical trial designs, outcome measures, and data collection methods. Recommendations include early dose-ranging studies and use of active comparators. Challenges and opportunities in assessing long-term safety by leveraging real-world data from electronic health records (EHRs) and claims data are discussed, along with insights from European registries and the evolving role of real-world evidence and artificial intelligence in regulatory evaluations. Endpoints for assessing disease activity and outcome measures used in RA and PsA trials are explored, emphasizing challenges in defining remission, assessing clinical response, and evaluating structural progression. The need for outcome measures that better reflect treatment targets and the potential of advanced imaging in future trials are highlighted. Challenges with placebo-controlled trials in RA are discussed and use of non-inferiority clinical trial design, in which new drugs are evaluated with active comparators, is proposed. Pragmatic trials in RA and PsA, employing decentralized approaches, are highlighted for their real-world relevance and administrative efficiencies. Strategies for identifying at-risk populations for RA and the challenges of using EHRs and insurance claims data in drug development are discussed. Registry data and digital health technologies show promise in bridging the gap between clinical trials and real-world effectiveness.


Assuntos
Antirreumáticos , Artrite Psoriásica , Artrite Reumatoide , Reumatologia , United States Food and Drug Administration , Humanos , Artrite Psoriásica/tratamento farmacológico , Estados Unidos , Artrite Reumatoide/tratamento farmacológico , Antirreumáticos/uso terapêutico , Ensaios Clínicos como Assunto , Avaliação de Resultados em Cuidados de Saúde , Sociedades Médicas
15.
Toxics ; 12(4)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38668520

RESUMO

Mycotoxin binders, in combination with enzymes degrading some mycotoxins, contribute to feed detoxification. Their use reduces economic losses and the negative impacts of mycotoxins on animal health and productivity in farm animals. The aim of this study was to evaluate the efficacy of a mycotoxin detoxifier on the expression of the ATP-binding cassette efflux transporters ABCB1 mRNA and ABCC2 mRNA, which transport xenobiotics and thus have a barrier function, in the tissues of pigs exposed to low doses of deoxynivalenol (DON, 1 mg/kg feed) and zearalenone (ZEN, 0.4 mg/kg feed) for 37 days. The levels of expression were determined by an RT-PCR, and the effect of the mycotoxin detoxifier (Mycofix Plus3.E) was evaluated by a comparison of results between healthy pigs (n = 6), animals treated with DON and ZEN (n = 6), and a group that received both mycotoxins and the detoxifier (n = 6). A significant downregulation of ABCB1 mRNA and ABCC2 mRNA was observed in the jejunum (p < 0.05). A tendencies toward the downregulation of ABCB1 mRNA and ABCC2 mRNA were found in the ileum and duodenum, respectively. The mycotoxin detoxifier restored the expression of ABCB1 mRNA to the level found in healthy animals but did not restore that of ABCC2 mRNA to the level of healthy animals in the jejunum.

16.
Clin Pharmacol Ther ; 115(4): 890-895, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38348530

RESUMO

A randomized, double-blind, placebo-controlled study (SAVEMORE trial) provided data to support an Emergency Use Authorization (EUA) of anakinra in hospitalized adults with positive results of direct severe acute respiratory syndrome-coronavirus 2 viral testing with pneumonia requiring supplemental oxygen (low- or high-flow oxygen) who are at risk of progressing to severe respiratory failure and likely to have an elevated plasma soluble urokinase plasminogen activator receptor (suPAR). Currently, the suPAR assay is not commercially available in the United States. An alternative method was needed to identify patients that best reflect the population in the clinical trial selected based on suPAR level ≥ 6 ng/mL at baseline. A machine learning approach based on data from the SAVEMORE trial was used to develop a scoring rule to identify patients who are likely to have a suPAR level ≥ 6 ng/mL at baseline. External validation of the scoring rule was conducted with data from a different trial (SAVE). This clinical scoring rule with high positive predictive value, high specificity, reasonable sensitivity, and biological relevance is expected to identify patients who are likely to have an elevated suPAR level ≥ 6 ng/mL at baseline. As such, it is included in the EUA to identify patients that fall within the authorized population for whom the known and potential benefits outweigh the known and potential risks of anakinra.


Assuntos
COVID-19 , Adulto , Humanos , Biomarcadores , Proteína Antagonista do Receptor de Interleucina 1/efeitos adversos , Oxigênio , Prognóstico , Receptores de Ativador de Plasminogênio Tipo Uroquinase , SARS-CoV-2 , Ensaios Clínicos Controlados Aleatórios como Assunto
17.
Arthritis Rheumatol ; 75(10): 1856-1866, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37067688

RESUMO

OBJECTIVE: Stakeholders met to address persistent challenges facing the development of therapeutics for polyarticular juvenile idiopathic arthritis (pJIA), which result in fewer approved therapies for children with pJIA than adults with rheumatoid arthritis (RA) and long lag times from adult RA approval to pediatric labeling. Ensuring that new medications are authorized in a timely manner to meet the needs of JIA patients worldwide is critically important to multiple stakeholders. METHODS: The Food and Drug Administration in collaboration with the University of Maryland Center for Regulatory Science and Innovation held a public workshop entitled "Accelerating Drug Development for pJIA" on October 2, 2019, to address challenges surrounding access to new medications for children and adolescents with pJIA. Regulatory, academic, and industry stakeholders, as well as patient representatives, participated in the workshop, which consisted of 4 sessions, including panel discussions. RESULTS: The workshop facilitated broad public discussion of challenges facing the development of pJIA therapeutics, highlighting areas of need and outlining opportunities to expedite development, while underscoring the necessity of close collaboration between all stakeholders, including patients and families. CONCLUSION: This report summarizes key aspects of the workshop, including the appropriate application of innovative approaches to the development of pJIA therapeutics, including extrapolation, to address current challenges and provide timely access to newer safe and effective treatments. Long-term safety assessment is of pressing concern to stakeholders and cannot be fully extrapolated from adult studies but requires consistent postmarketing long-term follow-up.


Assuntos
Artrite Juvenil , Artrite Reumatoide , Adulto , Adolescente , Humanos , Criança , Artrite Juvenil/tratamento farmacológico , Ensaios Clínicos como Assunto , Resultado do Tratamento , Desenvolvimento de Medicamentos
18.
Blood ; 116(5): 740-7, 2010 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-20457871

RESUMO

Autoimmunity is a surprisingly common complication of primary immunodeficiencies, yet the molecular mechanisms underlying this clinical observation are not well understood. One widely known example is provided by Wiskott-Aldrich syndrome (WAS), an X-linked primary immunodeficiency disorder caused by mutations in the gene encoding the WAS protein (WASp) with a high incidence of autoimmunity in affected patients. WASp deficiency affects T-cell antigen receptor (TCR) signaling and T-cell cytokine production, but its role in TCR-induced apoptosis, one of the mechanisms of peripheral immunologic tolerance, has not been investigated. We find that WASp-deficient mice produce autoantibodies and develop proliferative glomerulonephritis with immune complex deposition as they age. We also find that CD4(+) T lymphocytes from WASp-deficient mice undergo reduced apoptosis after restimulation through the TCR. While Fas-induced cell death is normal, WASp deficiency affects TCR-induced secretion of Fas ligand (FasL) and other components of secretory granules by CD4(+) T cells. These results describe a novel role of WASp in regulating TCR-induced apoptosis and FasL secretion and suggest that WASp-deficient mice provide a good model for the study of autoimmune manifestations of WAS and the development of more specific therapies for these complications.


Assuntos
Apoptose/imunologia , Doenças Autoimunes/etiologia , Linfócitos T CD4-Positivos/metabolismo , Proteína Ligante Fas/metabolismo , Glomerulonefrite Membranoproliferativa/imunologia , Receptores de Antígenos de Linfócitos T/fisiologia , Proteína da Síndrome de Wiskott-Aldrich/deficiência , Envelhecimento/imunologia , Animais , Anticorpos Antinucleares/biossíntese , Anticorpos Antinucleares/sangue , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Cruzamentos Genéticos , Grânulos Citoplasmáticos/metabolismo , Doenças do Complexo Imune/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Proteína da Síndrome de Wiskott-Aldrich/genética , Proteína da Síndrome de Wiskott-Aldrich/fisiologia
19.
Cell Mol Neurobiol ; 32(5): 903-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22350211

RESUMO

Several studies showed signs of autonomic dysfunction in patients with primary Sjögren's syndrome (pSS). Adrenomedullary function might be of importance for pSS pathogenesis by affecting salivary gland functions and modulating immune responses. The aim of the study was to evaluate the adrenomedullary hormonal system in patients with pSS. The glucagon test (1 mg i.v.) was performed in 18 pSS patients and 13 control subjects. During the test each patient had electrocardiographic and impedance cardiographic monitoring. Plasma epinephrine and norepinephrine were assayed by liquid chromatography with electrochemical detection after batch alumina extraction. Baseline concentrations of epinephrine and norepinephrine were comparable between pSS and controls. Glucagon administration induced a significant increase in systolic blood pressure, diastolic blood pressure, heart rate, cardiac output (P < 0.01), and stroke volume; however, the changes were comparable between pSS and controls. Epinephrine levels increased (P < 0.01) in response to glucagon administration while norepinephrine concentration did not change. There was no significant difference in neurochemical responses to glucagon between pSS and controls. In conclusion, the present results suggest normal adrenomedullary function in pSS.


Assuntos
Medula Suprarrenal/efeitos dos fármacos , Medula Suprarrenal/fisiopatologia , Glucagon/farmacologia , Síndrome de Sjogren/fisiopatologia , Adulto , Estudos de Casos e Controles , Epinefrina/sangue , Feminino , Glucagon/administração & dosagem , Humanos , Masculino , Norepinefrina/sangue , Síndrome de Sjogren/sangue
20.
Arthritis Care Res (Hoboken) ; 74(7): 1154-1162, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-33345469

RESUMO

OBJECTIVE: There is an unmet need for therapies that target the underlying pathophysiology of osteoarthritis (OA). However, defining appropriate measures for clinical trials of such therapies is challenging. Our objective was to propose concept clinical end points that directly capture clinical benefit in this setting and evaluate the feasibility of their use. METHODS: This analysis used the multicenter, longitudinal, observational Osteoarthritis Initiative (OAI) database. OAI participants primarily had knee OA, with follow-up of up to 9 years and assessments of joints, surgical interventions, performance outcomes, and patient-reported outcomes. We examined this data set to identify existing outcome measures of direct clinical benefit. We evaluated the feasibility of conducting trials using these candidate end points by estimating incidence rates and resulting required sample sizes and study durations in time-to-event analyses. RESULTS: We identified candidate end points based on total knee replacement (TKR) and composite end points defined by TKR and conservative thresholds of patient-reported outcomes of pain and function. Using time to TKR as an end point, a study with an average follow-up time of 3 years requires approximately 3,000 to 18,000 subjects, depending on effect size. Alternatively, for a composite end point, such as "time to TKR or severe pain or severely impaired functioning," the required sample sizes ranged from approximately 2,000 to 11,000 for a 3-year study. CONCLUSION: The proposed concept end points can reliably and feasibly evaluate the effectiveness of therapies for this unmet need. In particular, the composite end point approach can substantially reduce sample sizes (up to approximately 40%) compared to the use of TKR alone.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Humanos , Incidência , Osteoartrite do Joelho/diagnóstico , Osteoartrite do Joelho/cirurgia , Dor/cirurgia , Medição da Dor
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