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1.
Nature ; 614(7949): 659-663, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623548

RESUMO

Transmission spectroscopy1-3 of exoplanets has revealed signatures of water vapour, aerosols and alkali metals in a few dozen exoplanet atmospheres4,5. However, these previous inferences with the Hubble and Spitzer Space Telescopes were hindered by the observations' relatively narrow wavelength range and spectral resolving power, which precluded the unambiguous identification of other chemical species-in particular the primary carbon-bearing molecules6,7. Here we report a broad-wavelength 0.5-5.5 µm atmospheric transmission spectrum of WASP-39b8, a 1,200 K, roughly Saturn-mass, Jupiter-radius exoplanet, measured with the JWST NIRSpec's PRISM mode9 as part of the JWST Transiting Exoplanet Community Early Release Science Team Program10-12. We robustly detect several chemical species at high significance, including Na (19σ), H2O (33σ), CO2 (28σ) and CO (7σ). The non-detection of CH4, combined with a strong CO2 feature, favours atmospheric models with a super-solar atmospheric metallicity. An unanticipated absorption feature at 4 µm is best explained by SO2 (2.7σ), which could be a tracer of atmospheric photochemistry. These observations demonstrate JWST's sensitivity to a rich diversity of exoplanet compositions and chemical processes.

2.
Nature ; 600(7889): 450-455, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34912089

RESUMO

Early to Middle Miocene sea-level oscillations of approximately 40-60 m estimated from far-field records1-3 are interpreted to reflect the loss of virtually all East Antarctic ice during peak warmth2. This contrasts with ice-sheet model experiments suggesting most terrestrial ice in East Antarctica was retained even during the warmest intervals of the Middle Miocene4,5. Data and model outputs can be reconciled if a large West Antarctic Ice Sheet (WAIS) existed and expanded across most of the outer continental shelf during the Early Miocene, accounting for maximum ice-sheet volumes. Here we provide the earliest geological evidence proving large WAIS expansions occurred during the Early Miocene (~17.72-17.40 Ma). Geochemical and petrographic data show glacimarine sediments recovered at International Ocean Discovery Program (IODP) Site U1521 in the central Ross Sea derive from West Antarctica, requiring the presence of a WAIS covering most of the Ross Sea continental shelf. Seismic, lithological and palynological data reveal the intermittent proximity of grounded ice to Site U1521. The erosion rate calculated from this sediment package greatly exceeds the long-term mean, implying rapid erosion of West Antarctica. This interval therefore captures a key step in the genesis of a marine-based WAIS and a tipping point in Antarctic ice-sheet evolution.


Assuntos
Camada de Gelo , Elevação do Nível do Mar/história , Água do Mar/análise , Regiões Antárticas , Modelos Climáticos , História Antiga
3.
Immunity ; 44(3): 582-596, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26921108

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a devastating lung disorder with increasing incidence. Mitochondrial oxidative stress in alveolar macrophages is directly linked to pulmonary fibrosis. Mitophagy, the selective engulfment of dysfunctional mitochondria by autophagasomes, is important for cellular homeostasis and can be induced by mitochondrial oxidative stress. Here, we show Akt1 induced macrophage mitochondrial reactive oxygen species (ROS) and mitophagy. Mice harboring a conditional deletion of Akt1 in macrophages (Akt1(-/-)Lyz2-cre) and Park2(-/-) mice had impaired mitophagy and reduced active transforming growth factor-ß1 (TGF-ß1). Although Akt1 increased TGF-ß1 expression, mitophagy inhibition in Akt1-overexpressing macrophages abrogated TGF-ß1 expression and fibroblast differentiation. Importantly, conditional Akt1(-/-)Lyz2-cre mice and Park2(-/-) mice had increased macrophage apoptosis and were protected from pulmonary fibrosis. Moreover, IPF alveolar macrophages had evidence of increased mitophagy and displayed apoptosis resistance. These observations suggest that Akt1-mediated mitophagy contributes to alveolar macrophage apoptosis resistance and is required for pulmonary fibrosis development.


Assuntos
Fibrose Pulmonar Idiopática/imunologia , Pulmão/patologia , Macrófagos Alveolares/fisiologia , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/genética , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Fibrose , Humanos , Fibrose Pulmonar Idiopática/induzido quimicamente , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes , Mitofagia/genética , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt/genética , Espécies Reativas de Oxigênio/metabolismo , Deleção de Sequência/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
4.
J Immunol ; 211(11): 1714-1724, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37782053

RESUMO

Epidemiological evidence indicates that exposure to particulate matter is linked to the development of idiopathic pulmonary fibrosis (IPF) and increases the incidence of acute exacerbations of IPF. In addition to accelerating the rate of lung function decline, exposure to fine particulate matter (particulate matter smaller than 2.5 µm [PM2.5]) is a risk factor for increased mortality in subjects with IPF. In this article, we show that exposure to PM2.5 mediates monocyte recruitment and fibrotic progression in mice with established fibrosis. In mice with established fibrosis, bronchoalveolar lavage cells showed monocyte/macrophage heterogeneity after exposure to PM2.5. These cells had a significant inflammatory and anti-inflammatory signature. The mixed heterogeneity of cells contributed to the proinflammatory and anti-inflammatory response. Although monocyte-derived macrophages were recruited to the lung in bleomycin-injured mice treated with PM2.5, recruitment of monocytes expressing Ly6Chi to the lung promoted progression of fibrosis, reduced lung aeration on computed tomography, and impacted lung compliance. Ly6Chi monocytes isolated from PM2.5-exposed fibrotic mice showed enhanced expression of proinflammatory markers compared with fibrotic mice exposed to vehicle. Moreover, IPF bronchoalveolar lavage cells treated ex vivo with PM2.5 showed an exaggerated inflammatory response. Targeting Ly6Chi monocyte recruitment inhibited fibrotic progression in mice. Moreover, the adoptive transfer of Ly6Chi monocytes exacerbated established fibrosis. These observations suggest that enhanced recruitment of Ly6Chi monocytes with a proinflammatory phenotype mediates acute exacerbations of pulmonary fibrosis, and targeting these cells may provide a potential novel therapeutic target to protect against acute exacerbations of IPF.


Assuntos
Fibrose Pulmonar Idiopática , Pulmão , Humanos , Camundongos , Animais , Pulmão/patologia , Fibrose Pulmonar Idiopática/patologia , Fibrose , Bleomicina/uso terapêutico , Material Particulado/efeitos adversos , Anti-Inflamatórios/uso terapêutico
5.
J Biol Chem ; 299(5): 104695, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37044213

RESUMO

Pulmonary fibrosis is a progressive lung disease characterized by macrophage activation. Asbestos-induced expression of nicotinamide adenine dinucleotide phosphate hydrogen oxidase 4 (NOX4) in lung macrophages mediates fibrotic progression by the generation of mitochondrial reactive oxygen species (ROS), modulating mitochondrial biogenesis, and promoting apoptosis resistance; however, the mechanism(s) by which NOX4 localizes to mitochondria during fibrosis is not known. Here, we show that NOX4 localized to the mitochondrial matrix following asbestos exposure in lung macrophages via direct interaction with TIM23. TIM23 and NOX4 interaction was found in lung macrophages from human subjects with asbestosis, while it was absent in mice harboring a conditional deletion of NOX4 in lung macrophages. This interaction was localized to the proximal transmembrane region of NOX4. Mechanistically, TIM23 augmented NOX4-induced mitochondrial ROS and metabolic reprogramming to oxidative phosphorylation. Silencing TIM23 decreased mitochondrial ROS and oxidative phosphorylation. These observations highlight the important role of the mitochondrial translocase TIM23 interaction with NOX4. Moreover, this interaction is required for mitochondrial redox signaling and metabolic reprogramming in lung macrophages.


Assuntos
Macrófagos Alveolares , Mitocôndrias , NADPH Oxidase 4 , Animais , Humanos , Camundongos , Fibrose , Macrófagos Alveolares/metabolismo , Mitocôndrias/metabolismo , NADPH Oxidase 4/genética , NADPH Oxidase 4/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
Nature ; 557(7706): 526-529, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29736017

RESUMO

Broad absorption signatures from alkali metals, such as the sodium (Na I) and potassium (K I) resonance doublets, have long been predicted in the optical atmospheric spectra of cloud-free irradiated gas giant exoplanets1-3. However, observations have revealed only the narrow cores of these features rather than the full pressure-broadened profiles4-6. Cloud and haze opacity at the day-night planetary terminator are considered to be responsible for obscuring the absorption-line wings, which hinders constraints on absolute atmospheric abundances7-9. Here we report an optical transmission spectrum for the 'hot Saturn' exoplanet WASP-96b obtained with the Very Large Telescope, which exhibits the complete pressure-broadened profile of the sodium absorption feature. The spectrum is in excellent agreement with cloud-free, solar-abundance models assuming chemical equilibrium. We are able to measure a precise, absolute sodium abundance of logεNa = [Formula: see text], and use it as a proxy for the planet's atmospheric metallicity relative to the solar value (Zp/Zʘ = [Formula: see text]). This result is consistent with the mass-metallicity trend observed for Solar System planets and exoplanets10-12.

7.
J Neuroophthalmol ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016256

RESUMO

BACKGROUND: Visual symptoms are common after concussion. Rapid automatized naming (RAN) tasks are simple performance measures that demonstrate worse time scores in the setting of acute or more remote injury. METHODS: We evaluated the capacity for the Mobile Universal Lexicon Evaluation System (MULES) and Staggered Uneven Number (SUN) testing to be feasibly administered during preseason testing in a cohort of youth ice hockey athletes using a novel computerized app, the Mobile Integrated Cognitive Kit (MICK). Participants from a youth hockey league underwent preseason testing. RESULTS: Among 60 participants, the median age was 13 years (range 6-17). The median best time for the MULES was 49.8 seconds (range = 34.2-141.0) and the median best time for the SUN was 70.1 (range = 36.6-200.0). As is characteristic of timed performance measures, there were learning effects between the first and second trials for both the MULES (median improvement = 10.6 seconds, range = -32.3 to 92.0, P < 0.001, Wilcoxon signed-rank test) and SUN (median improvement = 2.4 seconds, range= -8.0 to 15.1, P = 0.001, Wilcoxon signed-rank test). Age was a predictor of best baseline times, with longer (worse) times for younger participants for MULES (P < 0.001, rs = -0.67) and SUN (P < 0.001, rs = -0.54 Spearman rank correlation). Degrees of learning effect did not vary with age (P > 0.05, rs = -0.2). CONCLUSIONS: Vision-based RAN tasks, such as the MULES and SUN, can be feasibly administered using the MICK app during preseason baseline testing in youth sports teams. The results suggest that more frequent baseline tests are necessary for preadolescent athletes because of the relation of RAN task performance to age.

8.
J Cardiovasc Electrophysiol ; 34(2): 302-312, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36571158

RESUMO

INTRODUCTION: Late-gadolinium enhancement magnetic resonance (LGE-MRI) imaging is increasingly used in management of atrial fibrillation (AFib) patients. Here, we assess the usefulness of LGE-MRI-based fibrosis quantification to predict arrhythmia recurrence in patients undergoing cryoballoon ablation. Our secondary goal was to compare two widely used fibrosis quantification methods. METHODS: In 102 AF patients undergoing LGE-MRI and cryoballoon ablation (mean age 62 years; 64% male; 59% paroxysmal AFib), atrial fibrosis was quantified using the pixel intensity histogram (PIH) and image intensity ratio (IIR) methods. PIH segmentations were completed by a third-party provider as part of the standard of care at our hospital; Image intensity ratio (IIR) segmentations of the same scans were carried out in our lab using a commercially available software package. Fibrosis burdens and spatial distributions for the two methods were compared. Patients were followed prospectively for recurrent arrhythmia following ablation. RESULTS: Average PIH fibrosis was 15.6 ± 5.8% of the left atrial (LA) volume. Depending on threshold (IIRthr ), the average IIR fibrosis (% of LA wall surface area) ranged from 5.0 ± 7.2% (IIRthr = 1.2) to 37.4 ± 10.9% (IIRthr = 0.97). An IIRthr of 1.03 demonstrated the greatest agreement between the methods, but spatial overlap of fibrotic areas delineated by the two methods was modest (Sorenson Dice coefficient: 0.49). Fourty-two patients (41.2%) had recurrent arrhythmia. PIH fibrosis successfully predicted recurrence (HR 1.07; p = .02) over a follow-up period of 362 ± 149 days; regardless of IIRthr , IIR fibrosis did not predict recurrence. CONCLUSIONS: PIH-based volumetric assessment of atrial fibrosis was modestly predictive of arrhythmia recurrence following cryoballoon ablation in this cohort. IIR-based fibrosis was not predictive of recurrence for any of the IIRthr values tested, and the overlap in designated areas of fibrosis between the PIH and IIR methods was modest. Caution must therefore be exercised when interpreting LA fibrosis from LGE-MRI, since the values and spatial pattern are methodology-dependent.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Fibrilação Atrial/patologia , Meios de Contraste , Gadolínio , Imageamento por Ressonância Magnética/métodos , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Átrios do Coração/patologia , Fibrose , Ablação por Cateter/métodos
9.
BMC Cancer ; 23(1): 1137, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996815

RESUMO

Novel strategies are needed to combat multidrug resistance in pancreatic ductal adenocarcinoma (PDAC). We applied genomic approaches to understand mechanisms of resistance in order to better inform treatment and precision medicine. Altered function of chromatin remodeling complexes contribute to chemoresistance. Our study generates and analyzes genomic and biochemical data from PDAC cells overexpressing HDAC1, a histone deacetylase involved in several chromatin remodeling complexes. We characterized the impact of overexpression on drug response, gene expression, HDAC1 binding, and chromatin structure using RNA-sequencing and ChIP-sequencing for HDAC1 and H3K27 acetylation. Integrative genomic analysis shows that HDAC1 overexpression promotes activation of key resistance pathways including epithelial to mesenchymal transition, cell cycle, and apoptosis through global chromatin remodeling. Target genes are similarly altered in patient tissues and show correlation with patient survival. We also demonstrate that direct targets of HDAC1 that also show altered chromatin are enriched near genes associated with altered GTPase activity. HDAC1 target genes identified using in vitro methods and observed in patient tissues were used to develop a clinically relevant nine-transcript signature associated with patient prognosis. Integration of multiple genomic and biochemical data types enables understanding of multidrug resistance and tumorigenesis in PDAC, a disease in desperate need of novel treatment strategies.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Transição Epitelial-Mesenquimal , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Fatores de Transcrição/genética , Cromatina/genética , Genômica , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo
10.
BMC Cancer ; 23(1): 524, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37291514

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers based on five-year survival rates. Genes contributing to chemoresistance represent novel therapeutic targets that can improve treatment response. Increased expression of ANGPTL4 in tumors correlates with poor outcomes in pancreatic cancer. METHODS: We used statistical analysis of publicly available gene expression data (TCGA-PAAD) to test whether expression of ANGPTL4 and its downstream targets, ITGB4 and APOL1, were correlated with patient survival. We measured the impact of ANGPTL4 overexpression in a common pancreatic cancer cell line, MIA PaCa-2 cells, using CRISPRa for overexpression and DsiRNA for knockdown. We characterized global gene expression changes associated with high levels of ANGPTL4 and response to gemcitabine treatment using RNA-sequencing. Gemcitabine dose response curves were calculated on modified cell lines by measuring cell viability with CellTiter-Glo (Promega). Impacts on cell migration were measured using a time course scratch assay. RESULTS: We show that ANGPTL4 overexpression leads to in vitro resistance to gemcitabine and reduced survival times in patients. Overexpression of ANGPTL4 induces transcriptional signatures of tumor invasion and metastasis, proliferation and differentiation, and inhibition of apoptosis. Analyses revealed an overlapping signature of genes associated with both ANGPTL4 activation and gemcitabine response. Increased expression of the genes in this signature in patient PDAC tissues was significantly associated with shorter patient survival. We identified 42 genes that were both co-regulated with ANGPTL4 and were responsive to gemcitabine treatment. ITGB4 and APOL1 were among these genes. Knockdown of either of these genes in cell lines overexpressing ANGPTL4 reversed the observed gemcitabine resistance and inhibited cellular migration associated with epithelial to mesenchymal transition (EMT) and ANGPTL4 overexpression. CONCLUSIONS: These data suggest that ANGPTL4 promotes EMT and regulates the genes APOL1 and ITGB4. Importantly, we show that inhibition of both targets reverses chemoresistance and decreases migratory potential. Our findings have revealed a novel pathway regulating tumor response to treatment and suggest relevant therapeutic targets in pancreatic cancer.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Apolipoproteína L1/genética , Apolipoproteína L1/metabolismo , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Transcriptoma , Transição Epitelial-Mesenquimal , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Gencitabina , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Proteína 4 Semelhante a Angiopoietina/genética , Proteína 4 Semelhante a Angiopoietina/metabolismo , Neoplasias Pancreáticas
11.
Chem Res Toxicol ; 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37703190

RESUMO

Forensic laboratories need quick and simple technology to improve turnaround times, while delivering reliable results. The goal of this study is first to create a simplified workflow to meet new Academy Standards Board requirements for urine testing in drug-facilitated crime investigations and, second, to create "ready-to-go", "hands-free" testing technology to further streamline analytical procedures. A first of its kind, the ToxBox forensic test kit is used to validate a single analytical procedure for opioids, benzodiazepines, cannabinoids, antidepressants, and several other drug classes. Method performance indicators follow accreditation requirements and include accuracy, precision, measurement uncertainty, calibration models, reportable range, sensitivity, specificity, carryover, interference, ion suppression/enhancement, and analyte stability. "Hands-free" testing platforms require the use of new suspended-state technology to stabilize NIST-traceable standards premanufactured at precise concentrations in the presence of sample preparation reagents. By suspending all reaction components in the solid state, with air gaps between the phases, reference standards and process controls are built in a "ready-to-go" format and stabilized for long-term storage in the presence of a sample matrix, ß-d-glucuronidase, and enzymatic buffers. "Hands-free" test kits are removed from storage, incubated at either ambient temperature or 60 °C, and assayed using validated methods. This is the first example of how complex forensic testing workflows can be streamlined with new "hands-free" testing strategies to meet analytical challenges associated with quantitative and confirmatory analyses.

12.
J Neuroophthalmol ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37983191

RESUMO

BACKGROUND: Hereditary optic neuropathies comprise a group of clinically and genetically heterogeneous disorders. Optic neuropathy has been previously reported in families with spastic paraplegia type 7 (SPG7) gene mutations. However, the typical time course and clinical presentation of SPG7-associated optic neuropathy is poorly understood. We report a series of 5 patients harboring pathogenic SPG7 mutations who originally presented to a neuro-ophthalmology clinic with symptoms of optic neuropathy. METHODS: Retrospective case series of 5 patients with pathogenic SPG7 mutations and optic atrophy from 3 neuro-ophthalmology clinics. Demographic, clinical, diagnostic, and treatment data were collected and reported by the clinician authors. RESULTS: Five patients ranging in age from 8 to 48 years were evaluated in the neuro-ophthalmology clinic. Although there were variable clinical presentations for each subject, all noted progressive vision loss, typically bilateral, and several also had previous diagnoses of peripheral neuropathy (e.g., Guillain-Barré Syndrome). Patients underwent neuro-ophthalmic examinations and testing with visual fields and optic coherence tomography of the retinal nerve fiber layer. Genetic testing revealed pathogenic variants in the SPG7 gene. CONCLUSIONS: Five patients presented to the neuro-ophthalmology clinic with progressive vision loss and were diagnosed with optic atrophy. Although each patient harbored an SPG7 mutation, this cohort was phenotypically and genotypically heterogeneous. Three patients carried the Ala510Val variant. The patients demonstrated varying degrees of visual acuity and visual field loss, although evaluations were completed during different stages of disease progression. Four patients had a previous diagnosis of peripheral neuropathy. This raises the prospect that a single pathogenic variant of SPG7 may be associated with peripheral neuropathy in addition to optic neuropathy. These results support the consideration of SPG7 testing in patients with high suspicion for genetic optic neuropathy, as manifested by symmetric papillomacular bundle damage without clear etiology on initial workup. Applied judiciously, genetic testing, including for SPG7, may help clarify the cause of unexplained progressive optic neuropathies.

13.
J Biol Chem ; 297(1): 100810, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34023385

RESUMO

Pulmonary fibrosis is a progressive lung disease often occurring secondary to environmental exposure. Asbestos exposure is an important environmental mediator of lung fibrosis and remains a significant cause of disease despite strict regulations to limit exposure. Lung macrophages play an integral role in the pathogenesis of fibrosis induced by asbestos (asbestosis), in part by generating reactive oxygen species (ROS) and promoting resistance to apoptosis. However, the mechanism by which macrophages acquire apoptosis resistance is not known. Here, we confirm that macrophages isolated from asbestosis subjects are resistant to apoptosis and show they are associated with enhanced mitochondrial content of NADPH oxidase 4 (NOX4), which generates mitochondrial ROS generation. Similar results were seen in chrysotile-exposed WT mice, while macrophages from Nox4-/- mice showed increased apoptosis. NOX4 regulated apoptosis resistance by activating Akt1-mediated Bcl-2-associated death phosphorylation. Demonstrating the importance of NOX4-mediated apoptosis resistance in fibrotic remodeling, mice harboring a conditional deletion of Nox4 in monocyte-derived macrophages exhibited increased apoptosis and were protected from pulmonary fibrosis. Moreover, resolution occurred when Nox4 was deleted in monocyte-derived macrophages in mice with established fibrosis. These observations suggest that NOX4 regulates apoptosis resistance in monocyte-derived macrophages and contributes to the pathogenesis of pulmonary fibrosis. Targeting NOX4-mediated apoptosis resistance in monocyte-derived macrophages may provide a novel therapeutic target to protect against the development and/or progression of pulmonary fibrosis.


Assuntos
Apoptose , Progressão da Doença , Fibrose Pulmonar Idiopática/enzimologia , Fibrose Pulmonar Idiopática/patologia , Macrófagos/enzimologia , Macrófagos/patologia , NADPH Oxidase 4/metabolismo , Animais , Linhagem Celular , Feminino , Pulmão/patologia , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Modelos Biológicos , Monócitos/metabolismo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo
14.
FASEB J ; 35(6): e21675, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34038004

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease associated with mitochondrial oxidative stress. Mitochondrial reactive oxygen species (mtROS) are important for cell homeostasis by regulating mitochondrial dynamics. Here, we show that IPF BAL cells exhibited increased mitochondrial biogenesis that is, in part, due to increased nuclear expression of peroxisome proliferator-activated receptor-É£ (PPARÉ£) coactivator (PGC)-1α. Increased PPARGC1A mRNA expression directly correlated with reduced pulmonary function in IPF subjects. Oxidant-mediated activation of the p38 MAPK via Akt1 regulated PGC-1α activation to increase mitochondrial biogenesis in monocyte-derived macrophages. Demonstrating the importance of PGC-1α in fibrotic repair, mice harboring a conditional deletion of Ppargc1a in monocyte-derived macrophages or mice administered a chemical inhibitor of mitochondrial division had reduced biogenesis and increased apoptosis, and the mice were protected from pulmonary fibrosis. These observations suggest that Akt1-mediated regulation of PGC-1α maintains mitochondrial homeostasis in monocyte-derived macrophages to induce apoptosis resistance, which contributes to the pathogenesis of pulmonary fibrosis.


Assuntos
Macrófagos Alveolares/patologia , Mitocôndrias/patologia , Dinâmica Mitocondrial , Estresse Oxidativo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Processamento de Proteína Pós-Traducional , Fibrose Pulmonar/patologia , Adolescente , Adulto , Idoso , Animais , Apoptose , Feminino , Homeostase , Humanos , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/química , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Fosforilação , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Adulto Jovem
15.
Evid Based Dent ; 23(2): 52-53, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35750724

RESUMO

Design Single-blind randomised controlled trial.Intervention Patient and parent pairs were randomly assigned via a random number generator to Group A or B. Both groups were given ten minutes to read a modified consent document. Group A (rehearsal) were given printouts that showed images of four core and four custom risks with handwritten descriptions of each risk and consequences. Group B were given an audio-visual presentation instead (PowerPoint). Interviews of each group were completed immediately after the informed consent and at six-month follow-up to assess recall and comprehension of information provided.Case selection Patients aged 11-18 years old and their parents attending for comprehensive orthodontic treatment at Ohio State University graduate orthodontic clinic. All subjects needed to be able to communicate in English, have no developmental disabilities or urgent medical conditions and neither the patients or parents or subjects' siblings were to have had orthodontic treatment in the last five years.Data analysis 1) Exploratory analysis to test for differences in demographics and anxiety between the two groups; 2) Multiple linear regression analysis was used to assess percentage of accurate responses at baseline and six months and the change between the two different groups, with differing baseline characteristics (p <0.05 was considered statistically significant); and 3) Intra- and inter-rater reliability was assessed using intra-class correlation.Results There were no significant differences in information retention and understanding between the two methods at six-month follow-up. For both groups, recall was significantly lower six months following consent-taking. Specific domains whereby information recall and comprehension are poor include: treatment method, risks, resorption and discomfort.Conclusions There is no superior method of consent-taking to ensure patients' and parents' information retention in the months following commencement of treatment. However, the study highlighted that current consent practices which are considered 'best practice' may be deficient.


Assuntos
Consentimento Livre e Esclarecido , Ortodontia , Adolescente , Criança , Compreensão , Termos de Consentimento , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Método Simples-Cego
16.
J Biol Chem ; 295(46): 15754-15766, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-32917723

RESUMO

Heavy metals released into the environment have a significant effect on respiratory health. Lung macrophages are important in mounting an inflammatory response to injury, but they are also involved in repair of injury. Macrophages develop mixed phenotypes in complex pathological conditions and polarize to a predominant phenotype depending on the duration and stage of injury and/or repair. Little is known about the reprogramming required for lung macrophages to switch between these divergent functions; therefore, understanding the mechanism(s) by which macrophages promote metabolic reprogramming to regulate lung injury is essential. Here, we show that lung macrophages polarize to a pro-inflammatory, classically activated phenotype after cadmium-mediated lung injury. Because metabolic adaptation provides energy for the diverse macrophage functions, these classically activated macrophages show metabolic reprogramming to glycolysis. RNA-Seq revealed up-regulation of glycolytic enzymes and transcription factors regulating glycolytic flux in lung macrophages from cadmium-exposed mice. Moreover, cadmium exposure promoted increased macrophage glycolytic function with enhanced extracellular acidification rate, glycolytic metabolites, and lactate excretion. These observations suggest that cadmium mediates the persistence of classically activated lung macrophages to exacerbate lung injury.


Assuntos
Cádmio/toxicidade , Lesão Pulmonar/etiologia , Macrófagos/metabolismo , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Cádmio/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Lipopolissacarídeos/farmacologia , Lesão Pulmonar/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
17.
Lab Invest ; 101(1): 116-124, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32773774

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disease without effective therapy. Animal models effectively reproducing IPF disease features are needed to study the underlying molecular mechanisms. Tree shrews are genetically, anatomically, and metabolically closer to humans than rodents or dogs; therefore, the tree shrew model presents a unique opportunity for translational research in lung fibrosis. Here we demonstrate that tree shrews have in vivo and in vitro fibrotic responses induced by bleomycin and pro-fibrotic mediators. Bleomycin exposure induced lung fibrosis evidenced by histological and biochemical fibrotic changes. In primary tree shrew lung fibroblasts, transforming growth factor beta-1 (TGF-ß1) induced myofibroblast differentiation, increased extracellular matrix (ECM) protein production, and focal adhesion kinase (FAK) activation. Tree shrew lung fibroblasts showed enhanced migration and increased matrix invasion in response to platelet derived growth factor BB (PDGF-BB). Inhibition of FAK significantly attenuated pro-fibrotic responses in lung fibroblasts. The data demonstrate that tree shrews have in vivo and in vitro fibrotic responses similar to that observed in IPF. The data, for the first time, support that the tree shrew model of lung fibrosis is a new and promising experimental animal model for studying the pathophysiology and therapeutics of lung fibrosis.


Assuntos
Modelos Animais de Doenças , Fibrose Pulmonar Idiopática/induzido quimicamente , Tupaiidae , Animais , Bleomicina , Diferenciação Celular , Fibroblastos/fisiologia , Fibrose , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Pulmão/patologia , Cultura Primária de Células
18.
BMC Cancer ; 21(1): 632, 2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34049503

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) patients suffer poor outcomes, including a five-year survival of below 10%. Poor outcomes result in part from therapeutic resistance that limits the impact of cytotoxic first-line therapy. Novel therapeutic approaches are needed, but currently no targeted therapies exist to treat PDAC. METHODS: To assess cellular resistance mechanisms common to four cytotoxic chemotherapies (gemcitabine, 5-fluorouracil, irinotecan, and oxaliplatin) used to treat PDAC patients, we performed four genome-wide CRISPR activation (CRISPRact) and CRISPR knock-out (CRISPRko) screens in two common PDAC cell lines (Panc-1 and BxPC3). We used pathway analysis to identify gene sets enriched among our hits and conducted RNA-sequencing and chromatin immunoprecipitation-sequencing (ChIP-seq) to characterize top hits from our screen. We used scratch assays to assess changes in cellular migration with HDAC1 overexpression. RESULTS: Our data revealed activation of ABCG2, a well-described efflux pump, as the most consistent mediator of resistance in each of our screens. CRISPR-mediated activation of genes involved in transcriptional co-repressor complexes also conferred resistance to multiple drugs. Expression of many of these genes, including HDAC1, is associated with reduced survival in PDAC patients. Up-regulation of HDAC1 in vitro increased promoter occupancy and expression of several genes involved in the epithelial-to-mesenchymal transition (EMT). These cells also displayed phenotypic changes in cellular migration consistent with activation of the EMT pathway. The expression changes resulting from HDAC1 activation were also observed with activation of several other co-repressor complex members. Finally, we developed a publicly available analysis tool, PancDS, which integrates gene expression profiles with our screen results to predict drug sensitivity in resected PDAC tumors and cell lines. CONCLUSION: Our results provide a comprehensive resource for identifying cellular mechanisms of drug resistance in PDAC, mechanistically implicate HDAC1, and co-repressor complex members broadly, in multi-drug resistance, and provide an analytical tool for predicting treatment response in PDAC tumors and cell lines.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pancreáticas/tratamento farmacológico , Antineoplásicos/uso terapêutico , Sistemas CRISPR-Cas/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Sequenciamento de Cromatina por Imunoprecipitação , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , RNA-Seq
19.
J Exp Biol ; 224(Pt Suppl 1)2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627463

RESUMO

The unprecedented advancement of global climate change is affecting thermal conditions across spatial and temporal scales. Reptiles with temperature-dependent sex determination (TSD) are uniquely vulnerable to even fine-scale variation in incubation conditions and are a model system for investigating the impacts of shifting temperatures on key physiological and life-history traits. The ways in which current and predicted future climatic conditions translate from macro- to ultra-fine scale temperature traces in subterranean nests is insufficiently understood. Reliably predicting the ways in which fine-scale, daily and seasonally fluctuating nest temperatures influence embryonic development and offspring phenotypes is a goal that remains constrained by many of the same logistical challenges that have persisted throughout more than four decades of research on TSD. However, recent advances in microclimate and developmental modeling should allow us to move farther away from relatively coarse metrics with limited predictive capacity and towards a fully mechanistic model of TSD that can predict incubation conditions and phenotypic outcomes for a variety of reptile species across space and time and for any climate scenario.


Assuntos
Mudança Climática , Processos de Determinação Sexual , Animais , Répteis , Razão de Masculinidade , Temperatura
20.
Environ Sci Technol ; 55(3): 1545-1554, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33449615

RESUMO

In hydraulic fracturing fluids, the oxidant persulfate is used to generate sulfate radical to break down polymer-based gels. However, sulfate radical may be scavenged by high concentrations of halides in hydraulic fracturing fluids, producing halogen radicals (e.g., Cl•, Cl2•-, Br•, Br2•-, and BrCl•-). In this study, we investigated how halogen radicals alter the mechanisms and kinetics of the degradation of organic chemicals in hydraulic fracturing fluids. Using a radical scavenger (i.e., isopropanol), we determined that halogenated products of additives such as cinnamaldehyde (i.e., α-chlorocinnamaldehyde and α-bromocinnamaldehyde) and citrate (i.e., trihalomethanes) were generated via a pathway involving halogen radicals. We next investigated the impact of halogen radicals on cinnamaldehyde degradation rates. The conversion of sulfate radicals to halogen radicals may result in selective degradation of organic compounds. Surprisingly, we found that the addition of halides to convert sulfate radicals to halogen radicals did not result in selective degradation of cinnamaldehyde over other compounds (i.e., benzoate and guar), which may challenge the application of radical selectivity experiments to more complex molecules. Overall, we find that halogen radicals, known to react in advanced oxidative treatment and sunlight photochemistry, also contribute to the unintended degradation and halogenation of additives in hydraulic fracturing fluids.


Assuntos
Fraturamento Hidráulico , Poluentes Químicos da Água , Halogenação , Halogênios , Compostos Orgânicos , Trialometanos
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