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1.
Cell ; 170(3): 564-576.e16, 2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28753430

RESUMO

Most human epithelial tumors harbor numerous alterations, making it difficult to predict which genes are required for tumor survival. To systematically identify cancer dependencies, we analyzed 501 genome-scale loss-of-function screens performed in diverse human cancer cell lines. We developed DEMETER, an analytical framework that segregates on- from off-target effects of RNAi. 769 genes were differentially required in subsets of these cell lines at a threshold of six SDs from the mean. We found predictive models for 426 dependencies (55%) by nonlinear regression modeling considering 66,646 molecular features. Many dependencies fall into a limited number of classes, and unexpectedly, in 82% of models, the top biomarkers were expression based. We demonstrated the basis behind one such predictive model linking hypermethylation of the UBB ubiquitin gene to a dependency on UBC. Together, these observations provide a foundation for a cancer dependency map that facilitates the prioritization of therapeutic targets.


Assuntos
Neoplasias/genética , Neoplasias/patologia , Linhagem Celular Tumoral , Humanos , Interferência de RNA , Software , Ubiquitina/genética
2.
Cell ; 165(2): 303-16, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27058663

RESUMO

Leukemia stem cells (LSCs) have the capacity to self-renew and propagate disease upon serial transplantation in animal models, and elimination of this cell population is required for curative therapies. Here, we describe a series of pooled, in vivo RNAi screens to identify essential transcription factors (TFs) in a murine model of acute myeloid leukemia (AML) with genetically and phenotypically defined LSCs. These screens reveal the heterodimeric, circadian rhythm TFs Clock and Bmal1 as genes required for the growth of AML cells in vitro and in vivo. Disruption of canonical circadian pathway components produces anti-leukemic effects, including impaired proliferation, enhanced myeloid differentiation, and depletion of LSCs. We find that both normal and malignant hematopoietic cells harbor an intact clock with robust circadian oscillations, and genetic knockout models reveal a leukemia-specific dependence on the pathway. Our findings establish a role for the core circadian clock genes in AML.


Assuntos
Fatores de Transcrição ARNTL/genética , Proteínas CLOCK/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/patologia , Animais , Ritmo Circadiano , Modelos Animais de Doenças , Técnicas de Inativação de Genes , Hematopoese , Humanos , Leucemia Mieloide Aguda/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neoplásicas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo
3.
Annu Rev Cell Dev Biol ; 33: 169-202, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28992442

RESUMO

Dorsal closure is a key process during Drosophila morphogenesis that models cell sheet movements in chordates, including neural tube closure, palate formation, and wound healing. Closure occurs midway through embryogenesis and entails circumferential elongation of lateral epidermal cell sheets that close a dorsal hole filled with amnioserosa cells. Signaling pathways regulate the function of cellular structures and processes, including Actomyosin and microtubule cytoskeletons, cell-cell/cell-matrix adhesion complexes, and endocytosis/vesicle trafficking. These orchestrate complex shape changes and movements that entail interactions between five distinct cell types. Genetic and laser perturbation studies establish that closure is robust, resilient, and the consequence of redundancy that contributes to four distinct biophysical processes: contraction of the amnioserosa, contraction of supracellular Actomyosin cables, elongation (stretching?) of the lateral epidermis, and zipping together of two converging cell sheets. What triggers closure and what the emergent properties are that give rise to its extraordinary resilience and fidelity remain key, extant questions.


Assuntos
Drosophila melanogaster/citologia , Modelos Biológicos , Morfogênese , Animais , Fenômenos Biomecânicos , Drosophila melanogaster/embriologia , Drosophila melanogaster/fisiologia , Transdução de Sinais
4.
Nat Immunol ; 16(5): 495-504, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25848864

RESUMO

The molecules and pathways that fine-tune innate inflammatory responses mediated by Toll-like receptor 7 (TLR7) remain to be fully elucidated. Using an unbiased genome-scale screen with short hairpin RNA (shRNA), we identified the receptor TREML4 as an essential positive regulator of TLR7 signaling. Macrophages from Treml4(-/-) mice were hyporesponsive to TLR7 agonists and failed to produce type I interferons due to impaired phosphorylation of the transcription factor STAT1 by the mitogen-activated protein kinase p38 and decreased recruitment of the adaptor MyD88 to TLR7. TREML4 deficiency reduced the production of inflammatory cytokines and autoantibodies in MRL/lpr mice, which are prone to systemic lupus erythematosus (SLE), and inhibited the antiviral immune response to influenza virus. Our data identify TREML4 as a positive regulator of TLR7 signaling and provide insight into the molecular mechanisms that control antiviral immunity and the development of autoimmunity.


Assuntos
Lúpus Eritematoso Sistêmico/imunologia , Macrófagos/fisiologia , Glicoproteínas de Membrana/metabolismo , Infecções por Orthomyxoviridae/imunologia , Orthomyxoviridae/imunologia , Receptores Imunológicos/metabolismo , Receptor 7 Toll-Like/metabolismo , Animais , Autoanticorpos/metabolismo , Autoimunidade/genética , Células Cultivadas , Citocinas/metabolismo , Humanos , Imunidade Inata/genética , Mediadores da Inflamação/metabolismo , Interferon Tipo I/metabolismo , Macrófagos/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/metabolismo , RNA Interferente Pequeno/genética , Receptores Imunológicos/genética , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Cell ; 151(7): 1457-73, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23245941

RESUMO

Wnt/ß-catenin signaling plays a key role in the pathogenesis of colon and other cancers; emerging evidence indicates that oncogenic ß-catenin regulates several biological processes essential for cancer initiation and progression. To decipher the role of ß-catenin in transformation, we classified ß-catenin activity in 85 cancer cell lines in which we performed genome-scale loss-of-function screens and found that ß-catenin active cancers are dependent on a signaling pathway involving the transcriptional regulator YAP1. Specifically, we found that YAP1 and the transcription factor TBX5 form a complex with ß-catenin. Phosphorylation of YAP1 by the tyrosine kinase YES1 leads to localization of this complex to the promoters of antiapoptotic genes, including BCL2L1 and BIRC5. A small-molecule inhibitor of YES1 impeded the proliferation of ß-catenin-dependent cancers in both cell lines and animal models. These observations define a ß-catenin-YAP1-TBX5 complex essential to the transformation and survival of ß-catenin-driven cancers.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Transformação Celular Neoplásica , Neoplasias do Colo/metabolismo , Fosfoproteínas/metabolismo , Proteínas com Domínio T/metabolismo , beta Catenina/metabolismo , Animais , Linhagem Celular Tumoral , Colo/embriologia , Colo/metabolismo , Neoplasias do Colo/patologia , Humanos , Proteínas Inibidoras de Apoptose/genética , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas c-yes/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-yes/metabolismo , Survivina , Fatores de Transcrição , Transcrição Gênica , Proteínas de Sinalização YAP , Peixe-Zebra/embriologia , Proteína bcl-X/genética , Quinases da Família src/antagonistas & inibidores
6.
Cell ; 150(4): 842-54, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22901813

RESUMO

Due to genome instability, most cancers exhibit loss of regions containing tumor suppressor genes and collateral loss of other genes. To identify cancer-specific vulnerabilities that are the result of copy number losses, we performed integrated analyses of genome-wide copy number and RNAi profiles and identified 56 genes for which gene suppression specifically inhibited the proliferation of cells harboring partial copy number loss of that gene. These CYCLOPS (copy number alterations yielding cancer liabilities owing to partial loss) genes are enriched for spliceosome, proteasome, and ribosome components. One CYCLOPS gene, PSMC2, encodes an essential member of the 19S proteasome. Normal cells express excess PSMC2, which resides in a complex with PSMC1, PSMD2, and PSMD5 and acts as a reservoir protecting cells from PSMC2 suppression. Cells harboring partial PSMC2 copy number loss lack this complex and die after PSMC2 suppression. These observations define a distinct class of cancer-specific liabilities resulting from genome instability.


Assuntos
Genes Essenciais , Instabilidade Genômica , Neoplasias/genética , ATPases Associadas a Diversas Atividades Celulares , Animais , Linhagem Celular Tumoral , Deleção Cromossômica , Dosagem de Genes , Genes Supressores de Tumor , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Transplante Heterólogo
7.
Blood ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38905635

RESUMO

The interaction between menin and histone-lysine N-methyltransferase 2A (KMT2A) is a critical dependency for KMT2A- or nucleophosmin 1 (NPM1)-altered leukemias and an emerging opportunity for therapeutic development. JNJ-75276617 is a novel, orally bioavailable, potent, and selective protein-protein interaction inhibitor of the binding between menin and KMT2A. In KMT2A-rearranged (KMT2A-r) and NPM1-mutant (NPM1c) AML cells, JNJ-75276617 inhibited the association of the menin-KMT2A complex with chromatin at target gene promoters, resulting in reduced expression of several menin-KMT2A target genes, including MEIS1 and FLT3. JNJ-75276617 displayed potent anti-proliferative activity across several AML and ALL cell lines and patient samples harboring KMT2A- or NPM1-alterations in vitro. In xenograft models of AML and ALL, JNJ-75276617 reduced leukemic burden and provided a significant dose-dependent survival benefit accompanied by expression changes of menin-KMT2A target genes. JNJ-75276617 demonstrated synergistic effects with gilteritinib in vitro in AML cells harboring KMT2A-r. JNJ-75276617 further exhibited synergistic effects with venetoclax and azacitidine in AML cells bearing KMT2A-r in vitro, and significantly increased survival in mice. Interestingly, JNJ-75276617 showed potent anti-proliferative activity in cell lines engineered with recently discovered mutations (MEN1M327I or MEN1T349M) that developed in patients refractory to the menin-KMT2A inhibitor revumenib. A co-crystal structure of menin in complex with JNJ-75276617 indicates a unique binding mode distinct from other menin-KMT2A inhibitors, including revumenib. JNJ-75276617 is being clinically investigated for acute leukemias harboring KMT2A or NPM1 alterations, as a monotherapy for relapsed/refractory (R/R) acute leukemia (NCT04811560), or in combination with AML-directed therapies (NCT05453903).

8.
Nature ; 588(7837): 337-343, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33239788

RESUMO

The zebrafish (Danio rerio) has been widely used in the study of human disease and development, and about 70% of the protein-coding genes are conserved between the two species1. However, studies in zebrafish remain constrained by the sparse annotation of functional control elements in the zebrafish genome. Here we performed RNA sequencing, assay for transposase-accessible chromatin using sequencing (ATAC-seq), chromatin immunoprecipitation with sequencing, whole-genome bisulfite sequencing, and chromosome conformation capture (Hi-C) experiments in up to eleven adult and two embryonic tissues to generate a comprehensive map of transcriptomes, cis-regulatory elements, heterochromatin, methylomes and 3D genome organization in the zebrafish Tübingen reference strain. A comparison of zebrafish, human and mouse regulatory elements enabled the identification of both evolutionarily conserved and species-specific regulatory sequences and networks. We observed enrichment of evolutionary breakpoints at topologically associating domain boundaries, which were correlated with strong histone H3 lysine 4 trimethylation (H3K4me3) and CCCTC-binding factor (CTCF) signals. We performed single-cell ATAC-seq in zebrafish brain, which delineated 25 different clusters of cell types. By combining long-read DNA sequencing and Hi-C, we assembled the sex-determining chromosome 4 de novo. Overall, our work provides an additional epigenomic anchor for the functional annotation of vertebrate genomes and the study of evolutionarily conserved elements of 3D genome organization.


Assuntos
Genoma/genética , Imageamento Tridimensional , Imagem Molecular , Sequências Reguladoras de Ácido Nucleico/genética , Peixe-Zebra/genética , Animais , Encéfalo/metabolismo , Sequência Conservada/genética , Metilação de DNA , Elementos Facilitadores Genéticos/genética , Epigênese Genética , Evolução Molecular , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/genética , Heterocromatina/química , Heterocromatina/genética , Heterocromatina/metabolismo , Humanos , Masculino , Camundongos , Especificidade de Órgãos , Regiões Promotoras Genéticas/genética , Análise de Célula Única , Especificidade da Espécie
9.
Proc Natl Acad Sci U S A ; 120(34): e2209735120, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37579162

RESUMO

The hydroxyl radical (OH) fuels atmospheric chemical cycling as the main sink for methane and a driver of the formation and loss of many air pollutants, but direct OH observations are sparse. We develop and evaluate an observation-based proxy for short-term, spatial variations in OH (ProxyOH) in the remote marine troposphere using comprehensive measurements from the NASA Atmospheric Tomography (ATom) airborne campaign. ProxyOH is a reduced form of the OH steady-state equation representing the dominant OH production and loss pathways in the remote marine troposphere, according to box model simulations of OH constrained with ATom observations. ProxyOH comprises only eight variables that are generally observed by routine ground- or satellite-based instruments. ProxyOH scales linearly with in situ [OH] spatial variations along the ATom flight tracks (median r2 = 0.90, interquartile range = 0.80 to 0.94 across 2-km altitude by 20° latitudinal regions). We deconstruct spatial variations in ProxyOH as a first-order approximation of the sensitivity of OH variations to individual terms. Two terms modulate within-region ProxyOH variations-water vapor (H2O) and, to a lesser extent, nitric oxide (NO). This implies that a limited set of observations could offer an avenue for observation-based mapping of OH spatial variations over much of the remote marine troposphere. Both H2O and NO are expected to change with climate, while NO also varies strongly with human activities. We also illustrate the utility of ProxyOH as a process-based approach for evaluating intermodel differences in remote marine tropospheric OH.

10.
Mol Biol Evol ; 41(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38124397

RESUMO

An individual's chronological age does not always correspond to the health of different tissues in their body, especially in cases of disease. Therefore, estimating and contrasting the physiological age of tissues with an individual's chronological age may be a useful tool to diagnose disease and its progression. In this study, we present novel metrics to quantify the loss of phylogenetic diversity in hematopoietic stem cells (HSCs), which are precursors to most blood cell types and are associated with many blood-related diseases. These metrics showed an excellent correspondence with an age-related increase in blood cancer incidence, enabling a model to estimate the phylogeny-derived age (phyloAge) of HSCs present in an individual. The HSC phyloAge was generally older than the chronological age of patients suffering from myeloproliferative neoplasms (MPNs). We present a model that relates excess HSC aging with increased MPN risk. It predicted an over 200 times greater risk based on the HSC phylogenies of the youngest MPN patients analyzed. Our new metrics are designed to be robust to sampling biases and do not rely on prior knowledge of driver mutations or physiological assessments. Consequently, they complement conventional biomarker-based methods to estimate physiological age and disease risk.


Assuntos
Transtornos Mieloproliferativos , Neoplasias , Humanos , Filogenia , Células-Tronco Hematopoéticas/metabolismo , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Envelhecimento
11.
Mol Plant Microbe Interact ; 37(6): 530-541, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38552146

RESUMO

Fusarium oxysporum f. sp. fragariae (Fof) race 1 is avirulent on cultivars with the dominant resistance gene FW1, while Fof race 2 is virulent on FW1-resistant cultivars. We hypothesized there was a gene-for-gene interaction between a gene at the FW1 locus and an avirulence gene (AvrFW1) in Fof race 1. To identify a candidate AvrFW1, we compared genomes of 24 Fof race 1 and three Fof race 2 isolates. We found one candidate gene that was present in race 1, was absent in race 2, was highly expressed in planta, and was homologous to a known effector, secreted in xylem 6 (SIX6). We knocked out SIX6 in two Fof race 1 isolates by homologous recombination. All SIX6 knockout transformants (ΔSIX6) gained virulence on FW1/fw1 cultivars, whereas ectopic transformants and the wildtype isolates remained avirulent. ΔSIX6 isolates were quantitatively less virulent on FW1/fw1 cultivars Fronteras and San Andreas than fw1/fw1 cultivars. Seedlings from an FW1/fw1 × fw1/fw1 population were genotyped for FW1 and tested for susceptibility to a SIX6 knockout isolate. Results suggested that additional minor-effect quantitative resistance genes could be present at the FW1 locus. This work demonstrates that SIX6 acts as an avirulence factor interacting with a resistance gene at the FW1 locus. The identification of AvrFW1 enables surveillance for Fof race 2 and provides insight into the mechanisms of FW1-mediated resistance. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Resistência à Doença , Fragaria , Fusarium , Doenças das Plantas , Fusarium/patogenicidade , Fusarium/genética , Doenças das Plantas/microbiologia , Virulência , Fragaria/microbiologia , Resistência à Doença/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Xilema/microbiologia
12.
Proc Natl Acad Sci U S A ; 118(9)2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33619099

RESUMO

Natural aerosols in pristine regions form the baseline used to evaluate the impact of anthropogenic aerosols on climate. Sea spray aerosol (SSA) is a major component of natural aerosols. Despite its importance, the abundance of SSA is poorly constrained. It is generally accepted that wind-driven wave breaking is the principle governing SSA production. This mechanism alone, however, is insufficient to explain the variability of SSA concentration at given wind speed. The role of other parameters, such as sea surface temperature (SST), remains controversial. Here, we show that higher SST promotes SSA mass generation at a wide range of wind speed levels over the remote Pacific and Atlantic Oceans, in addition to demonstrating the wind-driven SSA production mechanism. The results are from a global scale dataset of airborne SSA measurements at 150 to 200 m above the ocean surface during the NASA Atmospheric Tomography Mission. Statistical analysis suggests that accounting for SST greatly enhances the predictability of the observed SSA concentration compared to using wind speed alone. Our results support implementing SST into SSA source functions in global models to better understand the atmospheric burdens of SSA.

13.
Proc Natl Acad Sci U S A ; 118(42)2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34635596

RESUMO

Oceans emit large quantities of dimethyl sulfide (DMS) to the marine atmosphere. The oxidation of DMS leads to the formation and growth of cloud condensation nuclei (CCN) with consequent effects on Earth's radiation balance and climate. The quantitative assessment of the impact of DMS emissions on CCN concentrations necessitates a detailed description of the oxidation of DMS in the presence of existing aerosol particles and clouds. In the unpolluted marine atmosphere, DMS is efficiently oxidized to hydroperoxymethyl thioformate (HPMTF), a stable intermediate in the chemical trajectory toward sulfur dioxide (SO2) and ultimately sulfate aerosol. Using direct airborne flux measurements, we demonstrate that the irreversible loss of HPMTF to clouds in the marine boundary layer determines the HPMTF lifetime (τHPMTF < 2 h) and terminates DMS oxidation to SO2 When accounting for HPMTF cloud loss in a global chemical transport model, we show that SO2 production from DMS is reduced by 35% globally and near-surface (0 to 3 km) SO2 concentrations over the ocean are lowered by 24%. This large, previously unconsidered loss process for volatile sulfur accelerates the timescale for the conversion of DMS to sulfate while limiting new particle formation in the marine atmosphere and changing the dynamics of aerosol growth. This loss process potentially reduces the spatial scale over which DMS emissions contribute to aerosol production and growth and weakens the link between DMS emission and marine CCN production with subsequent implications for cloud formation, radiative forcing, and climate.

14.
Proc Natl Acad Sci U S A ; 118(52)2021 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-34930838

RESUMO

Ozone is the third most important anthropogenic greenhouse gas after carbon dioxide and methane but has a larger uncertainty in its radiative forcing, in part because of uncertainty in the source characteristics of ozone precursors, nitrogen oxides, and volatile organic carbon that directly affect ozone formation chemistry. Tropospheric ozone also negatively affects human and ecosystem health. Biomass burning (BB) and urban emissions are significant but uncertain sources of ozone precursors. Here, we report global-scale, in situ airborne measurements of ozone and precursor source tracers from the NASA Atmospheric Tomography mission. Measurements from the remote troposphere showed that tropospheric ozone is regularly enhanced above background in polluted air masses in all regions of the globe. Ozone enhancements in air with high BB and urban emission tracers (2.1 to 23.8 ppbv [parts per billion by volume]) were generally similar to those in BB-influenced air (2.2 to 21.0 ppbv) but larger than those in urban-influenced air (-7.7 to 6.9 ppbv). Ozone attributed to BB was 2 to 10 times higher than that from urban sources in the Southern Hemisphere and the tropical Atlantic and roughly equal to that from urban sources in the Northern Hemisphere and the tropical Pacific. Three independent global chemical transport models systematically underpredict the observed influence of BB on tropospheric ozone. Potential reasons include uncertainties in modeled BB injection heights and emission inventories, export efficiency of BB emissions to the free troposphere, and chemical mechanisms of ozone production in smoke. Accurately accounting for intermittent but large and widespread BB emissions is required to understand the global tropospheric ozone burden.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Biomassa , Ozônio , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/química , Atmosfera , Ecossistema , Incêndios , Ozônio/análise , Ozônio/química
15.
Toxicol Ind Health ; 40(8): 441-464, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38748851

RESUMO

The water extractability and acute aquatic toxicity of seven aliphatic diisocyanate-based prepolymer substances were investigated to determine if lesser reactivity of the aliphatic isocyanate groups, as well as increased ionization potential of the expected (aliphatic amine-terminated) polymeric hydrolysis products, would influence their aquatic behavior compared to that of previously investigated aromatic diisocyanate-based prepolymers. At loading rates of 100 and 1,000 mg/L, only the substances having log Kow ≤9 exhibited more than 1% extractability in water, and a maximum of 66% water extractability was determined for a prepolymer having log Kow = 2.2. For the more hydrophobic prepolymer substances (log Kow values from 18-37), water extractability was negligible. High-resolution mass spectrometric analyses were performed on the water-accommodated fractions (WAF) of the prepolymers, which indicated the occurrence of primary aliphatic amine-terminated polymer species having backbones and functional group equivalent weights aligned to those of the parent prepolymers. Measurements of reduced surface tension and presence of suspended micelles in the WAFs further supported the occurrence of these surface-active cationic polymer species as hydrolysis products of the prepolymers. Despite these characteristics, the water-extractable hydrolysis products were practically non-toxic to Daphnia magna. All of the substances tested exhibited 48-h EL50 values of >1,000 mg/L, with one exception of EL50 = 157 mg/L. The results from this investigation support a grouping of the aliphatic diisocyanate-based prepolymers as a class of water-reactive polymer substances having predictable aquatic exposure and a uniformly low hazard potential, consistent with that previously demonstrated for the aromatic diisocyanate-based prepolymers.


Assuntos
Isocianatos , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Isocianatos/química , Isocianatos/toxicidade , Polímeros/química , Polímeros/toxicidade , Daphnia/efeitos dos fármacos , Relação Estrutura-Atividade , Poliuretanos/química , Poliuretanos/toxicidade
16.
Curr Opin Gastroenterol ; 39(3): 156-162, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37144532

RESUMO

PURPOSE OF REVIEW: Nonalcoholic fatty liver disease (NAFLD) is strongly associated with obesity, but is also common in individuals with a normal body mass index (BMI), who also experience the hepatic inflammation, fibrosis, and decompensated cirrhosis associated with NAFLD progression. The clinical evaluation and treatment of NAFLD in this patient population are challenging for the gastroenterologist. A better understanding of the epidemiology, natural history, and outcomes of NAFLD in individuals with normal BMI is emerging. This review examines the relationship between metabolic dysfunction and clinical characteristics associated with NAFLD in normal-weight individuals. RECENT FINDINGS: Despite a more favorable metabolic profile, normal-weight NAFLD patients exhibit metabolic dysfunction. Visceral adiposity may be a critical risk factor for NAFLD in normal-weight individuals, and waist circumference may be better than BMI for assessing metabolic risk in these patients. Although screening for NAFLD is not presently recommended, recent guidelines may assist clinicians in the diagnosis, staging, and management of NAFLD in individuals with a normal BMI. SUMMARY: Individuals with a normal BMI likely develop NAFLD as a result of different etiologies. Subclinical metabolic dysfunction may be a key component of NAFLD in these patients, and efforts to better understand this relationship in this patient population are needed.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Índice de Massa Corporal , Fatores de Risco , Obesidade/complicações , Obesidade/epidemiologia , Cirrose Hepática/etiologia , Cirrose Hepática/complicações
17.
Environ Sci Technol ; 57(44): 17011-17021, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37874964

RESUMO

Biomass burning particulate matter (BBPM) affects regional air quality and global climate, with impacts expected to continue to grow over the coming years. We show that studies of North American fires have a systematic altitude dependence in measured BBPM normalized excess mixing ratio (NEMR; ΔPM/ΔCO), with airborne and high-altitude studies showing a factor of 2 higher NEMR than ground-based measurements. We report direct airborne measurements of BBPM volatility that partially explain the difference in the BBPM NEMR observed across platforms. We find that when heated to 40-45 °C in an airborne thermal denuder, 19% of lofted smoke PM1 evaporates. Thermal denuder measurements are consistent with evaporation observed when a single smoke plume was sampled across a range of temperatures as the plume descended from 4 to 2 km altitude. We also demonstrate that chemical aging of smoke and differences in PM emission factors can not fully explain the platform-dependent differences. When the measured PM volatility is applied to output from the High Resolution Rapid Refresh Smoke regional model, we predict a lower PM NEMR at the surface compared to the lofted smoke measured by aircraft. These results emphasize the significant role that gas-particle partitioning plays in determining the air quality impacts of wildfire smoke.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Incêndios , Fumaça/análise , Poluentes Atmosféricos/análise , Biomassa , Poluição do Ar/análise , Material Particulado/análise , Aerossóis/análise , Monitoramento Ambiental/métodos
18.
Acta Anaesthesiol Scand ; 67(8): 994-1017, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37345870

RESUMO

The set of guidelines for good clinical research practice in pharmacodynamic studies of neuromuscular blocking agents was developed following an international consensus conference in Copenhagen in 1996 (Viby-Mogensen et al., Acta Anaesthesiol Scand 1996, 40, 59-74); the guidelines were later revised and updated following the second consensus conference in Stockholm in 2005 (Fuchs-Buder et al., Acta Anaesthesiol Scand 2007, 51, 789-808). In view of new devices and further development of monitoring technologies that emerged since then, (e.g., electromyography, three-dimensional acceleromyography, kinemyography) as well as novel compounds (e.g., sugammadex) a review and update of these recommendations became necessary. The intent of these revised guidelines is to continue to help clinical researchers to conduct high-quality work and advance the field by enhancing the standards, consistency, and comparability of clinical studies. There is growing awareness of the importance of consensus-based reporting standards in clinical trials and observational studies. Such global initiatives are necessary in order to minimize heterogeneous and inadequate data reporting and to improve clarity and comparability between different studies and study cohorts. Variations in definitions of endpoints or outcome variables can introduce confusion and difficulties in interpretation of data, but more importantly, it may preclude building of an adequate body of evidence to achieve reliable conclusions and recommendations. Clinical research in neuromuscular pharmacology and physiology is no exception.


Assuntos
Bloqueio Neuromuscular , Bloqueadores Neuromusculares , Humanos , Bloqueadores Neuromusculares/farmacologia , Sugammadex , Bloqueio Neuromuscular/métodos
19.
J Shoulder Elbow Surg ; 32(5): 924-930, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36442830

RESUMO

BACKGROUND: Shoulder pain due to labral tears and biceps tendonitis is commonly found in softball players. Surgical options include labral repair and biceps tenodesis. Although past studies are limited by heterogeneous study groups from multiple sports, this is the first study that assesses clinical outcomes and return to play rates for fast-pitch softball players. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate the clinical outcomes and return to play for fast-pitch softball players treated for a superior labrum anterior posterior (SLAP) tear and recalcitrant biceps tendonitis with a biceps tenodesis compared with a traditional SLAP repair. We hypothesized that the biceps tenodesis would have comparable outcomes with a faster return to play compared with SLAP repair. METHODS: We performed a retrospective analysis on fast-pitch softball players treated surgically for SLAP tear, recalcitrant biceps tendonitis, or a combination between 2001 and 2019 at our institution. Inclusion criteria were fast-pitch softball players who underwent biceps tenodesis or a SLAP repair with greater than 2-year follow-up. Exclusion criteria involved slow-pitch softball players, patients with less than 2-year follow-up, and patients who had undergone concomitant procedures on the ipsilateral shoulder at the time of SLAP repair or biceps tenodesis. Follow-up was either self-reported through OBERD, a patient-reported outcomes (PRO)-managing software, or achieved over the phone. Follow-up data included American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form score, Andrews Carson Score, Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow Score, Numeric Rating Scale for Pain, and our institution-specific return-to-play questionnaire. We statistically compared players who underwent biceps tenodesis or a SLAP repair, and compared pitchers with position players using Student t tests and Fisher exact test with statistical significance determined to be P < .05. RESULTS: From 60 eligible patients identified, follow-up outcome data were successfully captured for 47 (78%). Of the 18 SLAP repair patients, 17 (94%) returned to full competition at an average of 7.9 months. Of the 29 patients who underwent biceps tenodesis, 27 (93%) returned to full competition at an average of 7.1 months. Statistical analysis of PRO scores for each group found no significant differences between any of the measures used to evaluate patient outcomes, including no statistical difference in pitchers compared with position players. CONCLUSION: In conclusion, this study demonstrated comparable outcomes between SLAP repairs and biceps tenodesis procedures among our study group of fast-pitch softball players. There was no significant difference between RTP times between the 2 groups.


Assuntos
Beisebol , Lesões do Ombro , Articulação do Ombro , Tendinopatia , Tenodese , Humanos , Tenodese/métodos , Volta ao Esporte , Estudos Retrospectivos , Lesões do Ombro/cirurgia , Articulação do Ombro/cirurgia , Artroscopia/métodos , Tendinopatia/cirurgia , Ruptura/cirurgia
20.
J Shoulder Elbow Surg ; 32(6): 1271-1279, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36907314

RESUMO

BACKGROUND AND HYPOTHESIS: Although numerous studies exist evaluating the short-term clinical outcomes of patients who have undergone elbow arthroscopy for osteochondritis dissecans (OCD) of the capitellum, the literature on minimum 2-year clinical outcomes in a large cohort of patients is limited. We hypothesized that the clinical outcomes of patients treated arthroscopically for OCD of the capitellum would be favorable, with improved postoperative subjective functional and pain scores and with an acceptable return-to-play rate. METHODS: A retrospective analysis of a prospectively collected surgical database was performed to identify all patients treated surgically for OCD of the capitellum at our institution from January 2001 to August 2018. The inclusion criteria for this study included a diagnosis of OCD of the capitellum treated arthroscopically with a minimum 2-year follow-up period. The exclusion criteria included any prior surgical treatment on the ipsilateral elbow, missing operative reports, and cases in which any portion of the surgical procedure was performed in an open manner. Follow-up was performed by telephone using multiple patient-reported outcome questionnaires: American Shoulder and Elbow Surgeons-Elbow (ASES-e), Andrews-Carson, and Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow Score (KJOC) questionnaires and our institution-specific return-to-play questionnaire. RESULTS: After the inclusion and exclusion criteria were applied to our surgical database, 107 eligible patients were identified. Of these, 90 were successfully contacted, for a follow-up rate of 84%. The mean age was 15.2 years, and the mean follow-up time was 8.3 years. A subsequent revision procedure was performed in 11 patients, for a 12% failure rate in these patients. The ASES-e pain score was an average of 4.0 on a maximum pain scale of 100, the ASES-e function score was an average of 34.5 of a maximum of 36, and the surgical satisfaction score was an average of 9.1 of 10. The average Andrews-Carson score was 87.1 of 100, and the average KJOC score for overhead athletes was 83.5 of 100. Additionally, of the 87 patients evaluated who played sports at the time of their arthroscopy, 81 (93%) returned to play. CONCLUSION: This study demonstrated an excellent return-to-play rate and satisfactory subjective questionnaire scores with a 12% failure rate following arthroscopy for OCD of the capitellum with a minimum 2-year follow-up period.


Assuntos
Artroscopia , Articulação do Cotovelo , Osteocondrite Dissecante , Adolescente , Humanos , Artroscopia/métodos , Seguimentos , Osteocondrite Dissecante/diagnóstico por imagem , Osteocondrite Dissecante/cirurgia , Dor , Estudos Retrospectivos , Resultado do Tratamento
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