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1.
Nature ; 601(7891): 74-78, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34912113

RESUMO

Anthropogenic releases of mercury (Hg)1-3 are a human health issue4 because the potent toxicant methylmercury (MeHg), formed primarily by microbial methylation of inorganic Hg in aquatic ecosystems, bioaccumulates to high concentrations in fish consumed by humans5,6. Predicting the efficacy of Hg pollution controls on fish MeHg concentrations is complex because many factors influence the production and bioaccumulation of MeHg7-9. Here we conducted a 15-year whole-ecosystem, single-factor experiment to determine the magnitude and timing of reductions in fish MeHg concentrations following reductions in Hg additions to a boreal lake and its watershed. During the seven-year addition phase, we applied enriched Hg isotopes to increase local Hg wet deposition rates fivefold. The Hg isotopes became increasingly incorporated into the food web as MeHg, predominantly from additions to the lake because most of those in the watershed remained there. Thereafter, isotopic additions were stopped, resulting in an approximately 100% reduction in Hg loading to the lake. The concentration of labelled MeHg quickly decreased by up to 91% in lower trophic level organisms, initiating rapid decreases of 38-76% of MeHg concentration in large-bodied fish populations in eight years. Although Hg loading from watersheds may not decline in step with lowering deposition rates, this experiment clearly demonstrates that any reduction in Hg loadings to lakes, whether from direct deposition or runoff, will have immediate benefits to fish consumers.


Assuntos
Monitoramento Ambiental , Recuperação e Remediação Ambiental , Peixes/metabolismo , Cadeia Alimentar , Lagos/química , Intoxicação por Mercúrio/veterinária , Mercúrio/análise , Animais , Isótopos/análise , Fatores de Tempo
2.
Phys Chem Chem Phys ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958416

RESUMO

We present an investigation of the ultrafast dynamics of the polycyclic aromatic hydrocarbon fluorene initiated by an intense femtosecond near-infrared laser pulse (810 nm) and probed by a weak visible pulse (405 nm). Using a multichannel detection scheme (mass spectra, electron and ion velocity-map imaging), we provide a full disentanglement of the complex dynamics of the vibronically excited parent molecule, its excited ionic states, and fragments. We observed various channels resulting from the strong-field ionization regime. In particular, we observed the formation of the unstable tetracation of fluorene, above-threshold ionization features in the photoelectron spectra, and evidence of ubiquitous secondary fragmentation. We produced a global fit of all observed time-dependent photoelectron and photoion channels. This global fit includes four parent ions extracted from the mass spectra, 15 kinetic-energy-resolved ionic fragments extracted from ion velocity map imaging, and five photoelectron channels obtained from electron velocity map imaging. The fit allowed for the extraction of 60 lifetimes of various metastable photoinduced intermediates.

3.
Arch Environ Contam Toxicol ; 86(3): 262-273, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38531980

RESUMO

In estuarine food webs, bivalve molluscs transfer nutrients and pollutants to higher trophic levels. Mercury (Hg) pollution is ubiquitous, but it is especially elevated in estuaries historically impacted by industrial activities, such as those in the U.S. Northeast. Monomethylmercury (MeHg), the organic form of Hg, is highly bioaccumulative and transferable in the food web resulting in the highest concentrations in the largest and oldest marine predators. Patterns of Hg concentrations in marine bivalve molluscs, however, are poorly understood. In this study, inorganic Hg (iHg), MeHg, and the total Hg (THg) in soft tissues of the northern quahogs (Mercenaria mercenaria), eastern oysters (Crassostrea virginica), and ribbed mussels (Geukensia demissa) from eastern Long Island sound, a temperate estuary of the western North Atlantic Ocean was investigated. In all three species, concentrations of THg remained similar between the four sampling months (May, June, July, and September), and were mostly independent of animal size. In quahogs, MeHg and iHg displayed significant (p < 0.05) positive (iHg in May and June) and negative (MeHg in July and September) changes with shell height. Variability in concentrations of THg, MeHg, and iHg, both inter- and intra-specifically was high and greater in quahogs and oysters (THg: 37, 39%, MeHg: 28, 39%, respectively) than in mussels (THg: 13%, MeHg: 20%). The percentage of THg that was MeHg (%MeHg) was also highly variable in the three species (range: 10-80%), highlighting the importance of measuring MeHg and not only THg in molluscs.


Assuntos
Crassostrea , Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Animais , Mercúrio/análise , Bioacumulação , Monitoramento Ambiental , Cadeia Alimentar , Poluentes Químicos da Água/análise
4.
Glob Chang Biol ; 29(14): 4152-4160, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37097011

RESUMO

Projections of coral reefs under climate change have important policy implications, but most analyses have focused on the intensification of climate-related physical stress rather than explicitly modelling how coral populations respond to stressors. Here, we analyse the future of the Great Barrier Reef (GBR) under multiple, spatially realistic drivers which allows less impacted sites to facilitate recovery. Under a Representative Concentration Pathway (RCP) 2.6 CMIP5 climate ensemble, where warming is capped at ~2°C, GBR mean coral cover declined mid-century but approached present-day levels towards 2100. This is considerably more optimistic than most analyses. However, under RCP4.5, mean coral cover declined by >80% by late-century, and reached near zero under RCP ≥6.0. While these models do not allow for adaptation, they significantly extend past studies by revealing demographic resilience of coral populations to low levels of additional warming, though more pessimistic outcomes might be expected under CMIP6. Substantive coral populations under RCP2.6 would facilitate long-term genetic adaptation, adding value to ambitious greenhouse emissions mitigation.


Assuntos
Antozoários , Animais , Recifes de Corais , Mudança Climática , Aclimatação , Demografia
5.
Environ Sci Technol ; 57(35): 13056-13066, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37603456

RESUMO

Estuaries are an important food source for the world's growing population, yet human health is at risk from elevated exposure to methylmercury (MeHg) via the consumption of estuarine fish. Moreover, the sources and cycling of MeHg in temperate estuarine ecosystems are poorly understood. Here, we investigated the seasonal and tidal patterns of mercury (Hg) forms in Long Island Sound (LIS), in a location where North Atlantic Ocean waters mix with the Connecticut River. We found that seasonal variations in Hg and MeHg in LIS followed the extent of riverine Hg delivery, while tides further exacerbated the remobilization of earlier deposited riverine Hg. The net production of MeHg near the river plume was significant compared to that in other locations and enhanced during high tide, possibly resulting from the enhanced microbial activity and organic carbon remineralization in the river plume. Statistical models, driven by our novel data, further support the hypothesis that the river-delivered organic matter and inorganic Hg drive net MeHg production in the estuarine water column. Our study sheds light on the significance of water column biogeochemical processes in temperate tidal estuaries in regulating MeHg levels and inspires new questions in our quest to understand MeHg sources and dynamics in coastal oceans.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Animais , Humanos , Estuários , Ecossistema , Oceano Atlântico
6.
Hum Mol Genet ; 29(12): 2076-2097, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32420594

RESUMO

Mutations of the RNA granule component TDRD7 (OMIM: 611258) cause pediatric cataract. We applied an integrated approach to uncover the molecular pathology of cataract in Tdrd7-/- mice. Early postnatal Tdrd7-/- animals precipitously develop cataract suggesting a global-level breakdown/misregulation of key cellular processes. High-throughput RNA sequencing integrated with iSyTE-bioinformatics analysis identified the molecular chaperone and cytoskeletal modulator, HSPB1, among high-priority downregulated candidates in Tdrd7-/- lens. A protein fluorescence two-dimensional difference in-gel electrophoresis (2D-DIGE)-coupled mass spectrometry screen also identified HSPB1 downregulation, offering independent support for its importance to Tdrd7-/- cataractogenesis. Lens fiber cells normally undergo nuclear degradation for transparency, posing a challenge: how is their cell morphology, also critical for transparency, controlled post-nuclear degradation? HSPB1 functions in cytoskeletal maintenance, and its reduction in Tdrd7-/- lens precedes cataract, suggesting cytoskeletal defects may contribute to Tdrd7-/- cataract. In agreement, scanning electron microscopy (SEM) revealed abnormal fiber cell morphology in Tdrd7-/- lenses. Further, abnormal phalloidin and wheat germ agglutinin (WGA) staining of Tdrd7-/- fiber cells, particularly those exhibiting nuclear degradation, reveals distinct regulatory mechanisms control F-actin cytoskeletal and/or membrane maintenance in post-organelle degradation maturation stage fiber cells. Indeed, RNA immunoprecipitation identified Hspb1 mRNA in wild-type lens lysate TDRD7-pulldowns, and single-molecule RNA imaging showed co-localization of TDRD7 protein with cytoplasmic Hspb1 mRNA in differentiating fiber cells, suggesting that TDRD7-ribonucleoprotein complexes may be involved in optimal buildup of key factors. Finally, Hspb1 knockdown in Xenopus causes eye/lens defects. Together, these data uncover TDRD7's novel upstream role in elevation of stress-responsive chaperones for cytoskeletal maintenance in post-nuclear degradation lens fiber cells, perturbation of which causes early-onset cataracts.


Assuntos
Catarata/genética , Proteínas do Olho/genética , Proteínas de Choque Térmico/genética , Chaperonas Moleculares/genética , Ribonucleoproteínas/genética , Animais , Catarata/patologia , Núcleo Celular/genética , Citoesqueleto/genética , Modelos Animais de Doenças , Oftalmopatias , Humanos , Cristalino/metabolismo , Cristalino/patologia , Camundongos , Microscopia Eletrônica de Varredura , Mutação/genética , RNA Mensageiro/genética , Xenopus laevis/genética
7.
Thorax ; 77(2): 203-209, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34404754

RESUMO

COVID-19 has different clinical stages, and effective therapy depends on the location and extent of the infection. The purpose of this review is to provide a background for understanding the progression of the disease throughout the pulmonary epithelium and discuss therapeutic options. The prime sites for infection that will be contrasted in this review are the conducting airways and the gas exchange portions of the lung. These two sites are characterised by distinct cellular composition and innate immune responses, which suggests the use of distinct therapeutic agents. In the nose, ciliated cells are the primary target cells for SARS-CoV-2 viral infection, replication and release. Infected cells shed their cilia, which disables mucociliary clearance. Evidence further points to a suppressed or incompletely activated innate immune response to SARS-CoV-2 infection in the upper airways. Asymptomatic individuals can still have a productive viral infection and infect others. In the gas exchange portion of the lung, the alveolar type II epithelial cell is the main target cell type. Cell death and marked innate immune response during infection likely contribute to alveolar damage and resultant acute respiratory distress syndrome. Alveolar infection can precipitate a hyperinflammatory state, which is the target of many therapies in severe COVID-19. Disease resolution in the lung is variable and may include scaring and long-term sequalae because the alveolar type II cells are also progenitor cells for the alveolar epithelium.


Assuntos
COVID-19 , Células Epiteliais , Humanos , Pulmão , Mucosa Respiratória , SARS-CoV-2
8.
Environ Sci Technol ; 56(18): 13076-13084, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36075084

RESUMO

Our understanding of the significance of dimethylmercury (DMHg) to the mercury (Hg) global ocean biogeochemical cycle is unclear because of the lack of detailed DMHg measurements in the water column. To our knowledge, 30 years of published studies have generated no more than 200 DMHg data points in the ocean surface waters and marine boundary layer (MBL). To improve the precision and reduce the uncertainty in determining DMHg in surface seawater, we developed a simple and robust DMHg automatic analyzer (DAA). This DAA system couples the main sampling and analytic steps, including a continuous flow chamber, with dual Carbotrap preconcentration, a gas chromatographic column, a cold vapor atomic fluorescence spectrometry, and a data logger for signal integration. We compared the operation, performance, and reproducibility between our DAA and the traditional manual analytic method. Its advantages include the ease of operation, the high time resolution and precision (30 min sampling and <5% relative variation), and long-term stability (2 weeks). The DAA can determine DMHg in both the MBL and surface seawater. The estimated detection limits for DMHg with the DAA in the atmosphere and in surface seawater are 10 pg/m3 and 0.2 fM, respectively. The successful DAA field measurement in coastal waters indicates that it can help detect the low DMHg concentration in surface seawater, and the time series DMHg data helped our understanding of the DMHg behavior (sources and sinks) and its flux into the MBL. The comparison of DMHg concentration in various oceans also suggests that the coastal region had the lowest averaged DMHg, up to an order of magnitude lower than other ecosystems.


Assuntos
Mercúrio , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Gases , Mercúrio/química , Compostos de Metilmercúrio , Oceanos e Mares , Reprodutibilidade dos Testes , Água do Mar/química , Água , Poluentes Químicos da Água/química
9.
Phys Chem Chem Phys ; 24(38): 23096-23105, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35876592

RESUMO

We investigated the dissociation of dications and trications of three polycyclic aromatic hydrocarbons (PAHs), fluorene, phenanthrene, and pyrene. PAHs are a family of molecules ubiquitous in space and involved in much of the chemistry of the interstellar medium. In our experiments, ions are formed by interaction with 30.3 nm extreme ultraviolet (XUV) photons, and their velocity map images are recorded using a PImMS2 multi-mass imaging sensor. Application of recoil-frame covariance analysis allows the total kinetic energy release (TKER) associated with multiple fragmentation channels to be determined to high precision, ranging 1.94-2.60 eV and 2.95-5.29 eV for the dications and trications, respectively. Experimental measurements are supported by Born-Oppenheimer molecular dynamics (BOMD) simulations.

10.
Environ Res ; 194: 110629, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33358725

RESUMO

Biogeochemical conditions and landscape can have strong influences on mercury bioaccumulation in fish, but these effects across regional scales and between sites with and without point sources of contamination are not well understood. Normal means clustering, a type of unsupervised machine learning, was used to analyze relationships between forage fish (Fundulus heteroclitus and Menidia menidia) mercury (Hg) concentrations and sediment and water column Hg and methylmercury (MeHg) concentrations, ancillary variables, and land classifications within the sub-watershed. The analysis utilized data from 38 sites in 8 estuarine systems in the Northeast US, collected over five years. A large range of mercury concentrations and land use proportions were observed across sites. The cluster correlations indicated that for Fundulus, benthic and pelagic Hg and MeHg concentrations were most related to tissue concentrations, while Menidia Hg was most related to water column MeHg, reflecting differing feeding modes between the species. For both species, dissolved MeHg was most related to tissue concentrations, with sediment Hg concentrations influential at contaminated sites. The models considering only uncontaminated sites showed reduced influence of bulk sediment MeHg for both species, but Fundulus retained sediment drivers at some sites, with dissolved MeHg still highly correlated for both. Dissolved organic carbon (DOC), chlorophyll, land use, and other ancillary variables were of lesser importance in driving bioaccumulation, though DOC was strongly related within some clusters, likely in relation to dissolved Hg. Land use, though not of primary importance, showed relationships opposite to those observed in freshwater, with development positively correlated and forests and agriculture negatively correlated with tissue concentrations across clusters and species. Clusters were composed of sites from geographically distinct systems, indicating the greater importance of small scale drivers of MeHg formation and uptake into the food web over system or region-wide influences.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Estuários , Peixes , Cadeia Alimentar , Mercúrio/análise , Compostos de Metilmercúrio/análise , Poluentes Químicos da Água/análise
11.
Am J Physiol Lung Cell Mol Physiol ; 319(1): L115-L120, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32493030

RESUMO

COVID-19 can be divided into three clinical stages, and one can speculate that these stages correlate with where the infection resides. For the asymptomatic phase, the infection mostly resides in the nose, where it elicits a minimal innate immune response. For the mildly symptomatic phase, the infection is mostly in the pseudostratified epithelium of the larger airways and is accompanied by a more vigorous innate immune response. In the conducting airways, the epithelium can recover from the infection, because the keratin 5 basal cells are spared and they are the progenitor cells for the bronchial epithelium. There may be more severe disease in the bronchioles, where the club cells are likely infected. The devastating third phase is in the gas exchange units of the lung, where ACE2-expressing alveolar type II cells and perhaps type I cells are infected. The loss of type II cells results in respiratory insufficiency due to the loss of pulmonary surfactant, alveolar flooding, and possible loss of normal repair, since type II cells are the progenitors of type I cells. The loss of type I and type II cells will also block normal active resorption of alveolar fluid. Subsequent endothelial damage leads to transudation of plasma proteins, formation of hyaline membranes, and an inflammatory exudate, characteristic of ARDS. Repair might be normal, but if the type II cells are severely damaged alternative pathways for epithelial repair may be activated, which would result in some residual lung disease.


Assuntos
Células Epiteliais Alveolares/virologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/virologia , Células Epiteliais/virologia , Pneumonia Viral/virologia , Células Epiteliais Alveolares/metabolismo , COVID-19 , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/terapia , Células Epiteliais/metabolismo , Epitélio/metabolismo , Epitélio/virologia , Humanos , Pulmão/metabolismo , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/terapia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/virologia , SARS-CoV-2
12.
Mol Genet Metab ; 130(2): 101-109, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32247585

RESUMO

BACKGROUND: Glycosaminoglycans (GAGs) are negatively charged long linear (highly sulfated) polysaccharides consisting of repeating disaccharide units that are expressed on the surfaces of all nucleated cells. The expression of GAGs is required for embryogenesis, regulation of cell growth and proliferation, maintenance of tissue hydration, and interactions of the cells via receptors. Mucopolysaccharidoses (MPS) are caused by deficiency of specific lysosomal enzymes that result in the accumulation of GAGs in multiple tissues leading to organ dysfunction. Therefore, GAGs are important biomarkers for MPS. Without any treatment, patients with severe forms of MPS die within the first two decades of life. SCOPE OF REVIEW: Accurate measurement of GAGs is important to understand the diagnosis and pathogenesis of MPS and to monitor therapeutic efficacy before, during, and after treatment of the disease. This review covers various qualitative and quantitative methods for measurement of GAGs, including dye specific, thin layer chromatography (TLC), capillary electrophoresis, high-performance liquid chromatography (HPLC), liquid chromatography-tandem mass spectrometry (LC-MS/MS), gas chromatography, ELISA, and automated high-throughput mass spectrometry. Major conclusion: There are several methods for GAG detection however, specific GAG detection in the various biological systems requires rapid, sensitive, specific, and cost-effective methods such as LC-MS/MS. GENERAL SIGNIFICANCE: This review will describe different methods for GAG detection and analysis, including their advantages and limitation.


Assuntos
Biomarcadores/metabolismo , Glicosaminoglicanos/metabolismo , Mucopolissacaridoses/diagnóstico , Humanos , Mucopolissacaridoses/metabolismo
13.
J Hum Genet ; 65(7): 557-567, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32277174

RESUMO

Mucopolysaccharidoses (MPS) are a subtype of lysosomal storage disorders (LSDs) characterized by the deficiency of the enzyme involved in the breakdown of glycosaminoglycans (GAGs). Mucopolysaccharidosis type I (MPS I, Hurler Syndrome) was endorsed by the U.S. Secretary of the Department of Health and Human Services for universal newborn screening (NBS) in February 2016. Its endorsement exemplifies the need to enhance the accuracy of diagnostic testing for disorders that are considered for NBS. The progression of MPS disorders typically incudes irreversible CNS involvement, severe bone dysplasia, and cardiac and respiratory issues. Patients with MPS have a significantly decreased quality of life if untreated and require timely diagnosis and management for optimal outcomes. NBS provides the opportunity to diagnose and initiate treatment plans for MPS patients as early as possible. Most newborns with MPS are asymptomatic at birth; therefore, it is crucial to have biomarkers that can be identified in the newborn. At present, there are tiered methods and different instrumentation available for this purpose. The screening of quick, cost-effective, sensitive, and specific biomarkers in patients with MPS at birth is important. Rapid newborn diagnosis enables treatments to maximize therapeutic efficacy and to introduce immune tolerance during the neonatal period. Currently, newborn screening for MPS I and II has been implemented and/or in pilot testing in several countries. In this review article, historical aspects of NBS for MPS and the prospect of newborn screening for MPS are described, including the potential tiers of screening.


Assuntos
Doenças por Armazenamento dos Lisossomos/diagnóstico , Mucopolissacaridoses/diagnóstico , Mucopolissacaridose I/diagnóstico , Triagem Neonatal , Glicosaminoglicanos , Humanos , Recém-Nascido , Doenças por Armazenamento dos Lisossomos/epidemiologia , Doenças por Armazenamento dos Lisossomos/genética , Doenças por Armazenamento dos Lisossomos/patologia , Mucopolissacaridoses/epidemiologia , Mucopolissacaridoses/genética , Mucopolissacaridoses/patologia , Mucopolissacaridose I/epidemiologia , Mucopolissacaridose I/genética , Mucopolissacaridose I/patologia , Qualidade de Vida , Espectrometria de Massas em Tandem
14.
Psychol Sci ; 31(6): 729-740, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32396452

RESUMO

Although declarative concepts (e.g., apple) have been shown to be identifiable from their functional MRI (fMRI) signatures, the correspondence has yet to be established for executing a complex procedure such as tying a knot. In this study, 7 participants were trained to tie seven knots. Their neural representations of these seven procedures were assessed with fMRI as they imagined tying each knot. A subset of the trained participants physically tied each knot in a later fMRI session. Findings demonstrated that procedural knowledge of tying a particular knot can be reliably identified from its fMRI signature, and such procedural signatures were found here in frontal, parietal, motor, and cerebellar regions. In addition, a classifier trained on mental tying signatures was able to reliably identify when participants were planning to tie knots before they physically tied them, which suggests that the mental-tying and physical-tying procedural signatures are similar. These findings indicate that fMRI activation patterns can illuminate the representation and organization of procedural knowledge.


Assuntos
Encéfalo/fisiologia , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Plasticidade Neuronal/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Desempenho Psicomotor , Tempo de Reação , Adulto Jovem
15.
J Exp Biol ; 223(Pt 20)2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33087470

RESUMO

The absorbtion of human-emitted CO2 by the oceans (elevated PCO2 ) is projected to alter the physiological performance of coral reef organisms by perturbing seawater chemistry (i.e. ocean acidification). Simultaneously, greenhouse gas emissions are driving ocean warming and changes in irradiance (through turbidity and cloud cover), which have the potential to influence the effects of ocean acidification on coral reefs. Here, we explored whether physiological impacts of elevated PCO2  on a coral-algal symbiosis (Pocillopora acuta-Symbiodiniaceae) are mediated by light and/or temperature levels. In a 39 day experiment, elevated PCO2  (962 versus 431 µatm PCO2 ) had an interactive effect with midday light availability (400 versus 800 µmol photons m-2 s-1) and temperature (25 versus 29°C) on areal gross and net photosynthesis, for which a decline at 29°C was ameliorated under simultaneous high-PCO2  and high-light conditions. Light-enhanced dark respiration increased under elevated PCO2  and/or elevated temperature. Symbiont to host cell ratio and chlorophyll a per symbiont increased at elevated temperature, whilst symbiont areal density decreased. The ability of moderately strong light in the presence of elevated PCO2  to alleviate the temperature-induced decrease in photosynthesis suggests that higher substrate availability facilitates a greater ability for photochemical quenching, partially offsetting the impacts of high temperature on the photosynthetic apparatus. Future environmental changes that result in moderate increases in light levels could therefore assist the P. acuta holobiont to cope with the 'one-two punch' of rising temperatures in the presence of an acidifying ocean.


Assuntos
Antozoários , Animais , Dióxido de Carbono , Clorofila A , Recifes de Corais , Humanos , Concentração de Íons de Hidrogênio , Oceanos e Mares , Fotossíntese , Água do Mar , Temperatura
16.
Int J Technol Assess Health Care ; 36(3): 217-223, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32383420

RESUMO

OBJECTIVES: While involving patients in health technology assessment (HTA) has become increasingly common and important around the world, little is known about the optimal methods of evaluating patients' involvement (PI) in HTA. This scoping review was undertaken to provide an overview of currently available methods for the evaluation of PI, specifically the impact of PI on HTA recommendations. METHODS: A literature search was conducted using nine databases as well as a grey literature search of the websites of 26 organizations related to the conduct, practice or research of HTA to identify articles, reports and abstracts related to the evaluation of PI impact in HTA. RESULTS: We identified 1,248 unique citations, six of which met our eligibility criteria. These six records (five articles, and one report) were all published after 2012. Four assessed the impact of patient experience submissions on final HTA recommendations; one evaluated the impact of direct involvement on HTA committees, and one assessed impact of multiple forms of involvement. Methods of evaluation included quantitative analyses of reimbursement decisions, qualitative interviews with those directly involved in an assessment, surveys of patient groups and committee members, and the review of HTA reports. CONCLUSIONS: Quantitative evaluation of PI based on associations with funding decisions may not be feasible or fully capture the relevant impact of PI in the assessment of health technologies. Rather, a combination of both qualitative and quantitative strategies may allow for the most comprehensive assessment of the impact of PI on HTA recommendations when possible.


Assuntos
Participação do Paciente , Avaliação da Tecnologia Biomédica , Humanos , Inquéritos e Questionários
17.
Am J Respir Cell Mol Biol ; 61(4): 481-491, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30917006

RESUMO

The discovery of mutant tyrosine kinases as oncogenic drivers of lung adenocarcinomas has changed the basic understanding of lung cancer development and therapy. Yet, expressed kinases (kinome) in lung cancer progenitor cells, as well as whether kinase expression and the overall kinome changes or is reprogrammed upon transformation, is incompletely understood. We hypothesized that the kinome differs between lung cancer progenitor cells, alveolar type II cells (ATII), and basal cells (BC) and that their respective kinomes undergo distinct lineage-specific reprogramming to adenocarcinomas and squamous cell carcinomas upon transformation. We performed RNA sequencing on freshly isolated human ATII, BC, and lung cancer cell lines to define the kinome in nontransformed cells and transformed cells. Our studies identified a unique kinome for ATII and BC and changes in their kinome upon transformation to their respective carcinomas.


Assuntos
Células-Tronco Adultas/enzimologia , Células Epiteliais Alveolares/enzimologia , Transformação Celular Neoplásica , Neoplasias Pulmonares/enzimologia , Pulmão/enzimologia , Proteínas de Neoplasias/análise , Proteínas Tirosina Quinases/análise , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Animais , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/genética , Linhagem da Célula , Células Cultivadas , Indução Enzimática , Humanos , Pulmão/citologia , Neoplasias Pulmonares/genética , Camundongos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/enzimologia , Proteínas Tirosina Quinases/biossíntese , Proteínas Tirosina Quinases/genética , RNA Mensageiro/análise , RNA Neoplásico/análise , Transcriptoma
18.
Am J Physiol Lung Cell Mol Physiol ; 317(2): L283-L294, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31166130

RESUMO

Epithelial-fibroblast interactions are thought to be very important in the adult lung in response to injury, but the specifics of these interactions are not well defined. We developed coculture systems to define the interactions of adult human alveolar epithelial cells with lung fibroblasts. Alveolar type II cells cultured on floating collagen gels reduced the expression of type 1 collagen (COL1A1) and α-smooth muscle actin (ACTA2) in fibroblasts. They also reduced fibroblast expression of hepatocyte growth factor (HGF), fibroblast growth factor 7 (FGF7, KGF), and FGF10. When type II cells were cultured at an air-liquid interface to maintain high levels of surfactant protein expression, this inhibitory activity was lost. When type II cells were cultured on collagen-coated tissue culture wells to reduce surfactant protein expression further and increase the expression of some type I cell markers, the epithelial cells suppressed transforming growth factor-ß (TGF-ß)-stimulated ACTA2 and connective tissue growth factor (CTGF) expression in lung fibroblasts. Our results suggest that transitional alveolar type II cells and likely type I cells but not fully differentiated type II cells inhibit matrix and growth factor expression in fibroblasts. These cells express markers of both type II cells and type I cells. This is probably a normal homeostatic mechanism to inhibit the fibrotic response in the resolution phase of wound healing. Defining how transitional type II cells convert activated fibroblasts into a quiescent state and inhibit the effects of TGF-ß may provide another approach to limiting the development of fibrosis after alveolar injury.


Assuntos
Células Epiteliais Alveolares/metabolismo , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Células Epiteliais Alveolares/efeitos dos fármacos , Células Cultivadas , Colágeno/farmacologia , Células Epiteliais/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Surfactantes Pulmonares/metabolismo
19.
Am J Physiol Lung Cell Mol Physiol ; 317(4): L475-L485, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31313616

RESUMO

The alveolus participates in gas exchange, which can be impaired by environmental factors and toxins. There is an increase in using electronic cigarettes (e-cigarettes); however, their effect on human primary alveolar epithelial cells is unknown. Human lungs were obtained from nonsmoker organ donors to isolate alveolar type II (ATII) cells. ATII cells produce and secrete pulmonary surfactant and restore the epithelium after damage, and mitochondrial function is important for their metabolism. Our data indicate that human ATII cell exposure to e-cigarette aerosol increased IL-8 levels and induced DNA damage and apoptosis. We also studied the cytoprotective effect of DJ-1 against ATII cell injury. DJ-1 knockdown in human primary ATII cells sensitized cells to mitochondrial dysfunction as detected by high mitochondrial superoxide production, decreased mitochondrial membrane potential, and calcium elevation. DJ-1 knockout (KO) mice were more susceptible to ATII cell apoptosis and lung injury induced by e-cigarette aerosol compared with wild-type mice. Regulation of the oxidative phosphorylation (OXPHOS) is important for mitochondrial function and protection against oxidative stress. Major subunits of the OXPHOS system are encoded by both nuclear and mitochondrial DNA. We found dysregulation of OXPHOS complexes in DJ-1 KO mice after exposure to e-cigarette aerosol, which could disrupt the nuclear/mitochondrial stoichiometry, resulting in mitochondrial dysfunction. Together, our results indicate that DJ-1 deficiency sensitizes ATII cells to damage induced by e-cigarette aerosol leading to lung injury.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Sistemas Eletrônicos de Liberação de Nicotina , Interleucina-8/genética , Nicotina/farmacologia , Proteína Desglicase DJ-1/genética , Aerossóis , Células Epiteliais Alveolares/citologia , Células Epiteliais Alveolares/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Cálcio/metabolismo , Dano ao DNA , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Interleucina-8/metabolismo , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Knockout , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Cultura Primária de Células , Proteína Desglicase DJ-1/deficiência , Proteína Desglicase DJ-1/metabolismo , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/metabolismo , Superóxidos/metabolismo
20.
Biol Blood Marrow Transplant ; 25(7): e226-e246, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30772512

RESUMO

Allogenic hematopoietic stem cell transplantation (HSCT) has proven to be a viable treatment option for a selected group of patients with mucopolysaccharidoses (MPS), including those with MPS types I, II, IVA, VI, and VII. Early diagnosis and timely referral to an expert in MPS are critical, followed by a complete examination and evaluation by a multidisciplinary team, including a transplantation physician. Treatment recommendations for MPS are based on multiple biological, sociological, and financial factors, including type of MPS, clinical severity, prognosis, present clinical signs and symptoms (disease stage), age at onset, rate of progression, family factors and expectations, financial burden, feasibility, availability, risks and benefits of available therapies such as HSCT, enzyme replacement therapy (ERT), surgical interventions, and other supportive care. International collaboration and data review are critical to evaluating the therapeutic efficacy and adverse effects of HSCT for MPS. Collaborative efforts to assess HSCT for MPS have been ongoing since the first attempt at HSCT in a patient with MPS reported in 1981. The accumulation of data since then has made it possible to identify early outcomes (ie, transplantation outcomes) and long-term disease-specific outcomes resulting from HSCT. The recent identification of predictive factors and the development of innovative regimens have significantly improved the outcomes of both engraftment failure and transplantation-related mortality. Assessment of long-term outcomes has considered a variety of factors, including type of MPS, type of graft, age at transplantation, and stage of disease progression, among others. Studies on long-term outcomes are considered a key factor in the use of HSCT in patients with MPS. These studies have shown the effects and limitations of HSCT on improving disease manifestations and quality of life. In this review, we summarize the efficacy, side effects, risks, and cost of HSCT for each type of MPS.


Assuntos
Transplante de Células-Tronco Hematopoéticas/história , Mucopolissacaridoses/história , Mucopolissacaridoses/terapia , Aloenxertos , História do Século XX , História do Século XXI , Humanos
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