RESUMO
Although RAF monomer inhibitors (type I.5, BRAF(V600)) are clinically approved for the treatment of BRAFV600-mutant melanoma, they are ineffective in non-BRAFV600 mutant cells1-3. Belvarafenib is a potent and selective RAF dimer (type II) inhibitor that exhibits clinical activity in patients with BRAFV600E- and NRAS-mutant melanomas. Here we report the first-in-human phase I study investigating the maximum tolerated dose, and assessing the safety and preliminary efficacy of belvarafenib in BRAFV600E- and RAS-mutated advanced solid tumours (NCT02405065, NCT03118817). By generating belvarafenib-resistant NRAS-mutant melanoma cells and analysing circulating tumour DNA from patients treated with belvarafenib, we identified new recurrent mutations in ARAF within the kinase domain. ARAF mutants conferred resistance to belvarafenib in both a dimer- and a kinase activity-dependent manner. Belvarafenib induced ARAF mutant dimers, and dimers containing mutant ARAF were active in the presence of inhibitor. ARAF mutations may serve as a general resistance mechanism for RAF dimer inhibitors as the mutants exhibit reduced sensitivity to a panel of type II RAF inhibitors. The combination of RAF plus MEK inhibition may be used to delay ARAF-driven resistance and suggests a rational combination for clinical use. Together, our findings reveal specific and compensatory functions for the ARAF isoform and implicate ARAF mutations as a driver of resistance to RAF dimer inhibitors.
Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Melanoma/tratamento farmacológico , Melanoma/genética , Mutação , Proteínas Proto-Oncogênicas A-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas A-raf/genética , Quinases raf/antagonistas & inibidores , Animais , Linhagem Celular , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Melanoma/patologia , Camundongos , Multimerização Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas A-raf/química , Quinases raf/químicaRESUMO
Since its inception, synthetic biology has overcome many technical barriers but is at a crossroads for high-precision biological design. Devising ways to fully utilize big biological data may be the key to achieving greater heights in synthetic biology.
Assuntos
Big Data , Biologia SintéticaRESUMO
The human microbiome is composed of a collection of dynamic microbial communities that inhabit various anatomical locations in the body. Accordingly, the coevolution of the microbiome with the host has resulted in these communities playing a profound role in promoting human health. Consequently, perturbations in the human microbiome can cause or exacerbate several diseases. In this Review, we present our current understanding of the relationship between human health and disease development, focusing on the microbiomes found across the digestive, respiratory, urinary, and reproductive systems as well as the skin. We further discuss various strategies by which the composition and function of the human microbiome can be modulated to exert a therapeutic effect on the host. Finally, we examine technologies such as multiomics approaches and cellular reprogramming of microbes that can enable significant advancements in microbiome research and engineering.
Assuntos
Microbiota , Humanos , TecnologiaRESUMO
Transcriptional enhanced associate domain family members 1 to 4 (TEADs) are a family of four transcription factors and the major transcriptional effectors of the Hippo pathway. In order to activate transcription, TEADs rely on interactions with other proteins, such as the transcriptional effectors Yes-associated protein and transcriptional co-activator with PDZ-binding motif. Nuclear protein interactions involving TEADs influence the transcriptional regulation of genes involved in cell growth, tissue homeostasis, and tumorigenesis. Clearly, protein interactions for TEADs are functionally important, but the full repertoire of TEAD interaction partners remains unknown. Here, we employed an affinity purification mass spectrometry approach to identify nuclear interacting partners of TEADs. We performed affinity purification mass spectrometry experiment in parallel in two different cell types and compared a wildtype TEAD bait protein to a nuclear localization sequence mutant that does not localize to the nucleus. We quantified the results using SAINT analysis and found a significant enrichment of proteins linked to DNA damage including X-ray repair cross-complementing protein 5 (XRCC5), X-ray repair cross-complementing protein 6 (XRCC6), poly(ADP-ribose) polymerase 1 (PARP1), and Rap1-interacting factor 1 (RIF1). In cellular assays, we found that TEADs co-localize with DNA damage-induced nuclear foci marked by histone H2AX phosphorylated on S139 (γH2AX) and Rap1-interacting factor 1. We also found that depletion of TEAD proteins makes cells more susceptible to DNA damage by various agents and that depletion of TEADs promotes genomic instability. Additionally, depleting TEADs dampens the efficiency of DNA double-stranded break repair in reporter assays. Our results connect TEADs to DNA damage response processes, positioning DNA damage as an important avenue for further research of TEAD proteins.
Assuntos
Dano ao DNA , Reparo do DNA , Fatores de Transcrição de Domínio TEA , Humanos , Carcinogênese/metabolismo , Reparo do DNA/fisiologia , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição de Domínio TEA/metabolismoRESUMO
SignificanceDeep profiling of the plasma proteome at scale has been a challenge for traditional approaches. We achieve superior performance across the dimensions of precision, depth, and throughput using a panel of surface-functionalized superparamagnetic nanoparticles in comparison to conventional workflows for deep proteomics interrogation. Our automated workflow leverages competitive nanoparticle-protein binding equilibria that quantitatively compress the large dynamic range of proteomes to an accessible scale. Using machine learning, we dissect the contribution of individual physicochemical properties of nanoparticles to the composition of protein coronas. Our results suggest that nanoparticle functionalization can be tailored to protein sets. This work demonstrates the feasibility of deep, precise, unbiased plasma proteomics at a scale compatible with large-scale genomics enabling multiomic studies.
Assuntos
Proteínas Sanguíneas , Aprendizado Profundo , Nanopartículas , Proteômica , Proteínas Sanguíneas/química , Nanopartículas/química , Coroa de Proteína/química , Proteoma , Proteômica/métodosRESUMO
The basal cell maintains the airway's respiratory epithelium as the putative resident stem cell. Basal cells are known to self-renew and differentiate into airway ciliated and secretory cells. However, it is not clear if every basal cell functions as a stem cell. To address functional heterogeneity amongst the basal cell population, we developed a novel monoclonal antibody, HLO1-6H5, that identifies a subset of KRT5+ (cytokeratin 5) basal cells. We used HLO1-6H5 and other known basal cell-reactive reagents to isolate viable airway subsets from primary human airway epithelium by Fluorescence Activated Cell Sorting. Isolated primary cell subsets were assessed for the stem cell capabilities of self-renewal and differentiation in the bronchosphere assay, which revealed that bipotent stem cells were, at minimum 3-fold enriched in the HLO1-6H5+ cell subset. Crosslinking-mass spectrometry identified the HLO1-6H5 target as a glycosylated TFRC/CD71 (transferrin receptor) proteoform. The HLO1-6H5 antibody provides a valuable new tool for identifying and isolating a subset of primary human airway basal cells that are substantially enriched for bipotent stem/progenitor cells and reveals TFRC as a defining surface marker for this novel cell subset.
Assuntos
Diferenciação Celular , Células Epiteliais , Queratina-5 , Mucosa Respiratória , Células-Tronco , Humanos , Células-Tronco/citologia , Células-Tronco/metabolismo , Queratina-5/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Mucosa Respiratória/citologia , Mucosa Respiratória/metabolismo , Receptores da Transferrina/metabolismo , Anticorpos Monoclonais , Antígenos CD/metabolismo , Células Cultivadas , Citometria de Fluxo/métodos , Biomarcadores/metabolismo , Separação Celular/métodosRESUMO
There is a significant unmet need for clinical reflex tests that increase the specificity of prostate-specific antigen blood testing, the longstanding but imperfect tool for prostate cancer diagnosis. Towards this endpoint, we present the results from a discovery study that identifies new prostate-specific antigen reflex markers in a large-scale patient serum cohort using differentiating technologies for deep proteomic interrogation. We detect known prostate cancer blood markers as well as novel candidates. Through bioinformatic pathway enrichment and network analysis, we reveal associations of differentially abundant proteins with cytoskeletal, metabolic, and ribosomal activities, all of which have been previously associated with prostate cancer progression. Additionally, optimized machine learning classifier analysis reveals proteomic signatures capable of detecting the disease prior to biopsy, performing on par with an accepted clinical risk calculator benchmark.
Assuntos
Biomarcadores Tumorais , Neoplasias da Próstata , Proteômica , Humanos , Masculino , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/sangue , Biomarcadores Tumorais/sangue , Proteômica/métodos , Espectrometria de Mobilidade Iônica/métodos , Antígeno Prostático Específico/sangue , Idoso , Aprendizado de Máquina , Pessoa de Meia-IdadeRESUMO
We demonstrate a transmitter and receiver in a silicon photonics platform for O-band optical communication that monolithically incorporates a modulator driver, traveling-wave Mach-Zehnder modulator, control circuitry, photodetector, and transimpedance amplifier (TIA) in the GlobalFoundries Fotonix (45SPCLO) platform. The transmitter and receiver show an open 112 Gbps PAM4 eye at a 4.3 pJ/bit energy efficiency, not including the laser. Extensive use of gain-peaking enables our modulator driver and TIA to achieve the high bandwidths needed in the 45â nm CMOS-silicon photonics process. Our results suggest an alternative to the frequent approach of bump-bonding BiCMOS drivers and TIAs to silicon photonics.
RESUMO
OBJECTIVE: Optimizing medical management and risk factor modification are underused strategies in patients with chronic limb-threatening ischemia (CLTI), despite evidence of improved outcomes. The Vascular Quality Initiative (VQI) registry is a tool to improve quality of vascular care. In this study, we used the VQI to evaluate trends in medical management in patients with CLTI undergoing peripheral vascular interventions (PVI), and the impact of changes in management on overall survival (OS), amputation-free survival (AFS), and limb salvage (LS). METHODS: Patients undergoing index PVI for CLTI between 2012 and 2016, with ≥24 months of follow-up were identified from the national VQI registry. Patient details including smoking status and medication use, OS, LS, and AFS were analyzed with linear-by-linear association, t test, and logistic regression. RESULTS: There were 12,370 PVI completed in 11,466 patients. There was a significant increase in infrapopliteal interventions (from 29.8% to 39.0%; P < .001) and PVI performed for tissue loss (from 59.1% to 66.5%; P < .001). The percentage of current smokers at time of PVI decreased (from 36.2% to 30.7%; P = .036). At discharge, statins were initiated in 25%, aspirin in 45%, and P2Y12 therapy in 58% of patients not receiving these medications before PVI. Over the course of follow-up, dual antiplatelet therapy (DAPT) (from 41.1% to 48.0%; P < .001), angiotensin-converting enzyme (ACE) inhibitor (from 46.2% to 51.3%; P < .001), and statin (from 70.4% to 77.5%; P < .001) use increased. Combined DAPT, ACE inhibitor and statin use increased from 33.6% to 39.6% (P ≤ .001). Significant improvement in 24-month OS and AFS was noted (OS, from 90.9% to 93.7% [P = .002]: AFS, from 81.2% to 83.1% [P = .046]), but not LS (from 89.6% to 89.0%; P = .83). Combined therapy with P2Y12 inhibitors, statins and ACE inhibitors was an independent predictor of improved OS (hazard ratio, 0.61; 95% confidence interval, 0.39-0.96; P = .034). DAPT was independent predictor of improved LS (hazard ratio, 0.83; 95% confidence interval, 0.79-0.87; P < .007). CONCLUSIONS: Antiplatelet, ACE inhibitor, and statin use increased over the study period and was associated with improved OS and AFS. LS trends did not change significantly over time, possibly owing to the inclusion of patients with a greater disease burden or inadequate medical management. Medical management, although improved, remained far from optimal and represents an area for continued development.
Assuntos
Procedimentos Endovasculares , Inibidores de Hidroximetilglutaril-CoA Redutases , Doença Arterial Periférica , Humanos , Isquemia Crônica Crítica de Membro , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Medição de Risco , Procedimentos Endovasculares/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/terapia , Isquemia/diagnóstico , Isquemia/terapia , Fatores de Risco , Salvamento de Membro , Inibidores da Enzima Conversora de Angiotensina , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The treatment of patients with relapsed or refractory lymphoid neoplasms represents a significant clinical challenge. Here, we identify the pro-survival BCL-2 protein family member MCL-1 as a resistance factor for the BCL-2 inhibitor venetoclax in non-Hodgkin lymphoma (NHL) cell lines and primary NHL samples. Mechanistically, we show that the antibody-drug conjugate polatuzumab vedotin promotes MCL-1 degradation via the ubiquitin/proteasome system. This targeted MCL-1 antagonism, when combined with venetoclax and the anti-CD20 antibodies obinutuzumab or rituximab, results in tumor regressions in preclinical NHL models, which are sustained even off-treatment. In a Phase Ib clinical trial (NCT02611323) of heavily pre-treated patients with relapsed or refractory NHL, 25/33 (76%) patients with follicular lymphoma and 5/17 (29%) patients with diffuse large B-cell lymphoma achieved complete or partial responses with an acceptable safety profile when treated with the recommended Phase II dose of polatuzumab vedotin in combination with venetoclax and an anti-CD20 antibody.
Assuntos
Imunoconjugados , Linfoma não Hodgkin , Humanos , Proteína de Sequência 1 de Leucemia de Células Mieloides/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/patologia , Rituximab/uso terapêutico , Imunoconjugados/uso terapêuticoRESUMO
Approximately 200 BRAF mutant alleles have been identified in human tumours. Activating BRAF mutants cause feedback inhibition of GTP-bound RAS, are RAS-independent and signal either as active monomers (class 1) or constitutively active dimers (class 2). Here we characterize a third class of BRAF mutants-those that have impaired kinase activity or are kinase-dead. These mutants are sensitive to ERK-mediated feedback and their activation of signalling is RAS-dependent. The mutants bind more tightly than wild-type BRAF to RAS-GTP, and their binding to and activation of wild-type CRAF is enhanced, leading to increased ERK signalling. The model suggests that dysregulation of signalling by these mutants in tumours requires coexistent mechanisms for maintaining RAS activation despite ERK-dependent feedback. Consistent with this hypothesis, melanomas with these class 3 BRAF mutations also harbour RAS mutations or NF1 deletions. By contrast, in lung and colorectal cancers with class 3 BRAF mutants, RAS is typically activated by receptor tyrosine kinase signalling. These tumours are sensitive to the inhibition of RAS activation by inhibitors of receptor tyrosine kinases. We have thus defined three distinct functional classes of BRAF mutants in human tumours. The mutants activate ERK signalling by different mechanisms that dictate their sensitivity to therapeutic inhibitors of the pathway.
Assuntos
Melanoma/enzimologia , Melanoma/genética , Mutação , Proteína Oncogênica p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Animais , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Indóis/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Células NIH 3T3 , Neurofibromatose 1/genética , Proteína Oncogênica p21(ras)/metabolismo , Multimerização Proteica , Piridonas/farmacologia , Pirimidinonas/farmacologia , Sulfonamidas/farmacologia , Vemurafenib , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The ubiquitin system regulates essential cellular processes in eukaryotes. Ubiquitin is ligated to substrate proteins as monomers or chains and the topology of ubiquitin modifications regulates substrate interactions with specific proteins. Thus ubiquitination directs a variety of substrate fates including proteasomal degradation. Deubiquitinase enzymes cleave ubiquitin from substrates and are implicated in disease; for example, ubiquitin-specific protease-7 (USP7) regulates stability of the p53 tumour suppressor and other proteins critical for tumour cell survival. However, developing selective deubiquitinase inhibitors has been challenging and no co-crystal structures have been solved with small-molecule inhibitors. Here, using nuclear magnetic resonance-based screening and structure-based design, we describe the development of selective USP7 inhibitors GNE-6640 and GNE-6776. These compounds induce tumour cell death and enhance cytotoxicity with chemotherapeutic agents and targeted compounds, including PIM kinase inhibitors. Structural studies reveal that GNE-6640 and GNE-6776 non-covalently target USP7 12 Å distant from the catalytic cysteine. The compounds attenuate ubiquitin binding and thus inhibit USP7 deubiquitinase activity. GNE-6640 and GNE-6776 interact with acidic residues that mediate hydrogen-bond interactions with the ubiquitin Lys48 side chain, suggesting that USP7 preferentially interacts with and cleaves ubiquitin moieties that have free Lys48 side chains. We investigated this idea by engineering di-ubiquitin chains containing differential proximal and distal isotopic labels and measuring USP7 binding by nuclear magnetic resonance. This preferential binding protracted the depolymerization kinetics of Lys48-linked ubiquitin chains relative to Lys63-linked chains. In summary, engineering compounds that inhibit USP7 activity by attenuating ubiquitin binding suggests opportunities for developing other deubiquitinase inhibitors and may be a strategy more broadly applicable to inhibiting proteins that require ubiquitin binding for full functional activity.
Assuntos
Aminopiridinas/química , Aminopiridinas/farmacologia , Indazóis/química , Indazóis/farmacologia , Fenóis/química , Fenóis/farmacologia , Piridinas/química , Piridinas/farmacologia , Peptidase 7 Específica de Ubiquitina/antagonistas & inibidores , Ubiquitina/metabolismo , Animais , Ligação Competitiva , Linhagem Celular Tumoral , Sinergismo Farmacológico , Feminino , Humanos , Camundongos , Camundongos SCID , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/patologia , Ligação Proteica , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Proto-Oncogênicas c-pim-1/antagonistas & inibidores , Especificidade por Substrato , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina/química , Peptidase 7 Específica de Ubiquitina/química , Peptidase 7 Específica de Ubiquitina/deficiência , Peptidase 7 Específica de Ubiquitina/metabolismoRESUMO
BACKGROUND: Statin therapy is recommended in all patients with peripheral arterial disease (PAD). Its impact on reduction in mortality has been well-documented, yet effect on limb-specific outcomes has been less conclusive. Differences among PAD subgroups or variability of statin use may contribute to the inconsistent findings. We evaluated statin use in patients who underwent peripheral endovascular intervention (PVI) for chronic limb-threatening ischemia (CLTI) and its impact on overall survival (OS), amputation-free survival (AFS) and limb salvage (LS). METHODS: The national Vascular Quality Initiative was queried for the index PVI for CLTI during the period 2010-2016; follow-up (FU) through 2020. Demographics, comorbidities, operative details, and FU status were recorded. Patients were categorized as E-Statin: statin use pre-PVI through discharge (D/C) and FU or N-Statin: No statins pre-PVI, at D/C or any time during FU. The propensity score matched model (PSM) was constructed. Groups were compared using chi-square, Kaplan-Meier survival and Cox regression analysis. RESULTS: There were 9,089 index PVI in 8,402 patients; E-Statin: 7149 index PVI in 6,591 patients; and N-Statin: 1940 index PVI in 1811 patients. The mean age was 69 ± 12 years and 58% were male. Statin use was associated with improved 3-year OS-E Statin: 92.9% ± 0.9 versus N Statin: 91.1% ± 2.2%; P = 0.003; hazard ratio (HR): Exp (B) (95% confidence interval): 0.66 (0.44-0.99); P = 0.047 and remained significant following PSM: E Statin: 95.1% ± 0.2% versus 90.8% ± 0.3%; P = 0.02; HR: 0.50 (0.27-0.92); P = 0.025. No significant differences in 3-year LS or AFS were noted between the prematched groups; LS: E Statin: 83.7% ± 0.8 versus N Statin: 84.0% ± 1.7%; P = 0.89; HR: 1.09 (0.88-1.35); P = 0.44; AFS-E Statin: 77.2% ± 1.1% versus 76.1% ± 2.5%; P = 0.17; HR: 0.97 (0.79-1.18); P = 0.74. or following PSM: AFS: 80.2% ± 2.8% vs. 74.7% ± 3.9%; P = 0.53, HR: 0.92 (0.72-1.19); P = 0.54; LS 85.3% ± 1.9% vs. 83.5% ± 2.6%; P = 0.51, HR: 1.08 (0.83-1.4); P = 0.57. Statins significantly improved LS among those with renal failure: 67.8% ± 2.6% vs. 59.7% ± 4.4%; P = 0.003; HR: 56 (0.40-0.79); P = 0.001. CONCLUSIONS: Statins are independently associated with improved OS in patients who undergo PVI for CLTI and should be considered for all barring intolerance. Statin use was associated with improved LS in patients with end-stage renal disease. Additional research is needed in this area, particularly, the impact of statin therapy in high-risk CLTI subgroups.
Assuntos
Procedimentos Endovasculares , Inibidores de Hidroximetilglutaril-CoA Redutases , Doença Arterial Periférica , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Salvamento de Membro , Isquemia Crônica Crítica de Membro , Fatores de Risco , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Resultado do Tratamento , Isquemia/diagnóstico por imagem , Isquemia/terapia , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Estudos RetrospectivosRESUMO
The DNA damage response (DDR) comprises multiple functions that collectively preserve genomic integrity and suppress tumorigenesis. The Mre11 complex and ATM govern a major axis of the DDR and several lines of evidence implicate that axis in tumor suppression. Components of the Mre11 complex are mutated in approximately five percent of human cancers. Inherited mutations of complex members cause severe chromosome instability syndromes, such as Nijmegen Breakage Syndrome, which is associated with strong predisposition to malignancy. And in mice, Mre11 complex mutations are markedly more susceptible to oncogene- induced carcinogenesis. The complex is integral to all modes of DNA double strand break (DSB) repair and is required for the activation of ATM to effect DNA damage signaling. To understand which functions of the Mre11 complex are important for tumor suppression, we undertook mining of cancer genomic data from the clinical sequencing program at Memorial Sloan Kettering Cancer Center, which includes the Mre11 complex among the 468 genes assessed. Twenty five mutations in MRE11 and RAD50 were modeled in S. cerevisiae and in vitro. The mutations were chosen based on recurrence and conservation between human and yeast. We found that a significant fraction of tumor-borne RAD50 and MRE11 mutations exhibited separation of function phenotypes wherein Tel1/ATM activation was severely impaired while DNA repair functions were mildly or not affected. At the molecular level, the gene products of RAD50 mutations exhibited defects in ATP binding and hydrolysis. The data reflect the importance of Rad50 ATPase activity for Tel1/ATM activation and suggest that inactivation of ATM signaling confers an advantage to burgeoning tumor cells.
Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Carcinogênese/genética , Saccharomyces cerevisiae/genética , Animais , Dano ao DNA/genética , Reparo do DNA/genética , Enzimas Reparadoras do DNA/genética , Genômica/métodos , Proteína Homóloga a MRE11/genética , Mutação/genética , Células Sf9 , Transdução de Sinais/genética , Proteínas Supressoras de Tumor/genéticaRESUMO
Crystallographic defects are essential to the functional properties of semiconductors, controlling everything from conductivity to optical properties and catalytic activity. In nanocrystals, too, defect engineering with extrinsic dopants has been fruitful. Although intrinsic defects like vacancies can be equally useful, synthetic strategies for controlling their generation are comparatively underdeveloped. Here, we show that intrinsic defect concentration can be tuned during the synthesis of colloidal metal oxide nanocrystals by the addition of metal salts. Although not incorporated in the nanocrystals, the metal salts dissociate at high temperatures, promoting the dissociation of carboxylate ligands from metal precursors, leading to the introduction of oxygen vacancies. For example, the concentration of oxygen vacancies can be controlled up to 9% in indium oxide nanocrystals. This method is broadly applicable as we demonstrate by generating intrinsic defects in metal oxide nanocrystals of various morphologies and compositions.
Assuntos
Nanopartículas Metálicas , Sais , Óxidos , Metais , OxigênioRESUMO
Fatty acids are derived from diet and fermentative processes by the intestinal flora. Two to five carbon chain fatty acids, termed short chain fatty acids (SCFA) are increasingly recognized to play a role in intestinal homeostasis. However, the characteristics of slightly longer 6 to 10 carbon, medium chain fatty acids (MCFA), derived primarily from diet, are less understood. Here, we demonstrated that SCFA and MCFA have divergent immunomodulatory propensities. SCFA down-attenuated host pro-inflammatory IL-1ß, IL-6, and TNFα response predominantly through the TLR4 pathway, whereas MCFA augmented inflammation through TLR2. Butyric (C4) and decanoic (C10) acid displayed most potent modulatory effects within the SCFA and MCFA, respectively. Reduction in TRAF3, IRF3 and TRAF6 expression were observed with butyric acid. Decanoic acid induced up-regulation of GPR84 and PPARγ and altered HIF-1α/HIF-2α ratio. These variant immune characteristics of the fatty acids which differ by just several carbon atoms may be attributable to their origins, with SCFA being primarily endogenous and playing a physiological role, and MCFA exogenously from the diet.
Assuntos
Ácidos Graxos Voláteis/metabolismo , Ácidos Graxos/metabolismo , Imunomodulação , Biomarcadores , Ácido Butírico/metabolismo , Candida/fisiologia , Citocinas/metabolismo , Dieta , Microbioma Gastrointestinal , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imunomodulação/genética , Mediadores da Inflamação/metabolismo , Receptor 4 Toll-Like/metabolismoRESUMO
BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected over 21 million people worldwide since August 16, 2020. Compared to PCR and serology tests, SARS-CoV-2 antigen assays are underdeveloped, despite their potential to identify active infection and monitor disease progression. METHODS: We used Single Molecule Array (Simoa) assays to quantitatively detect SARS-CoV-2 spike, S1 subunit, and nucleocapsid antigens in the plasma of patients with coronavirus disease (COVID-19). We studied plasma from 64 patients who were COVID-19 positive, 17 who were COVID-19 negative, and 34 prepandemic patients. Combined with Simoa anti-SARS-CoV-2 serological assays, we quantified changes in 31 SARS-CoV-2 biomarkers in 272 longitudinal plasma samples obtained for 39 patients with COVID-19. Data were analyzed by hierarchical clustering and were compared to longitudinal RT-PCR test results and clinical outcomes. RESULTS: SARS-CoV-2 S1 and N antigens were detectable in 41 out of 64 COVID-19 positive patients. In these patients, full antigen clearance in plasma was observed a mean ± 95% CI of 5 ± 1 days after seroconversion and nasopharyngeal RT-PCR tests reported positive results for 15 ± 5 days after viral-antigen clearance. Correlation between patients with high concentrations of S1 antigen and ICU admission (77%) and time to intubation (within 1 day) was statistically significant. CONCLUSIONS: The reported SARS-CoV-2 Simoa antigen assay is the first to detect viral antigens in the plasma of patients who were COVID-19 positive to date. These data show that SARS-CoV-2 viral antigens in the blood are associated with disease progression, such as respiratory failure, in COVID-19 cases with severe disease.
Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/sangue , COVID-19/diagnóstico , Progressão da Doença , SARS-CoV-2/química , SARS-CoV-2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/sangue , Teste Sorológico para COVID-19 , Proteínas do Nucleocapsídeo de Coronavírus/sangue , Feminino , Hospitalização , Humanos , Unidades de Terapia Intensiva , Intubação , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Fosfoproteínas/sangue , Prognóstico , Subunidades Proteicas/sangue , Glicoproteína da Espícula de Coronavírus/sangueRESUMO
BACKGROUND AND AIMS: Although most large nonpedunculated colorectal lesions can be safely and efficaciously removed using EMR, the use of colectomy for benign colorectal lesions appears to be increasing. The reason(s) is unclear. We aimed to determine the use and adverse events of EMR in the United States. METHODS: We used Optum's de-identified Clinformatics Data Mart Database (2003-2016), a database from a large national insurance provider, to identify all colonoscopies performed with either EMR or simple polypectomy on adult patients from January 1, 2011 to December 31, 2015. We measured time trends, regional variation, and adverse event rates. We assessed risk factors for adverse events using multivariate logistic regression. RESULTS: The rate of EMR use in the US increased from 1.62% of all colonoscopies in 2011 to 2.48% of colonoscopies in 2015 (P < .001). There were, however, significant regional differences in the use of EMRs, from 2.4% of colonoscopies in the western United States to 2.0% of colonoscopies in the southern United States. Between 2011 and 2015, we found stable rates of perforation, GI bleeding (GIB), infections, and cardiac adverse events and decreasing rates of admissions after EMR. In our multivariate model, EMR was an independent risk factor for adverse events, albeit the rates of adverse events were low (1.35% GIB, .22% perforation). CONCLUSIONS: Use of EMR is rising in the United States, although there is significant regional variation. The rates of adverse events after EMR and polypectomies were low and stable, confirming the continued safety of EMR procedures. A better understanding of the regional barriers and facilitators may improve the use of EMR as the standard management for benign colorectal lesions throughout the United States.
Assuntos
Pólipos do Colo/cirurgia , Colonoscopia/estatística & dados numéricos , Ressecção Endoscópica de Mucosa/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Pólipos do Colo/patologia , Colonoscopia/efeitos adversos , Bases de Dados Factuais , Ressecção Endoscópica de Mucosa/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Utilização de Procedimentos e Técnicas , Estudos Retrospectivos , Fatores de Tempo , Estados UnidosRESUMO
OBJECTIVE: Endometrioid ovarian carcinoma (EOVC) is an uncommon subtype of epithelial ovarian carcinoma and its molecular characteristics have been incompletely described. Prior sequencing investigations have been limited to targeted gene panels. We performed whole-exome sequencing to build an unbiased genetic profile of molecular alterations in endometrioid ovarian tumors with a goal to better understand this disease in the context of epithelial ovarian cancer and endometrioid uterine cancers. METHODS: Whole-exome sequencing was performed on EOVC samples (n = 26) and matched normals (n = 15). Gene mutations, mutational signatures and copy number variations (CNVs) informed a multi-dimensional regression classifier allowing for comparison to endometrial carcinoma (UCEC) and high grade serous ovarian carcinoma (HGSC). RESULTS: EOVC has a distinct and heterogeneous genomic profile. Identified significantly mutated genes in EOVC (PTEN, CTNNB1, PIK3CA, KMT2D, KMT2B, PIK3R1, ARID1A and TP53) occurred at similar frequencies in UCEC. Hypermutation, resulting from both mismatch repair deficiency (MMRd) and POLE mutation, was observed in EOVC at a frequency similar to UCEC. Like UCEC, a subset of EOVC cases closely resembled HGSC, harboring TP53 mutations, homologous recombination deficiency (HRd) mutation signatures and widespread CNVs. A machine-learning classifier confirmed the heterogeneous composition of EOVC. Potential therapeutic targets were identified in 62% of EOVC cases. We validated our findings in an orthogonal clinical sequencing registry of EOVC cases. CONCLUSIONS: We identified that EOVC are a molecularly heterogeneous group of epithelial ovarian cancers with distinct mutational signatures. In an age of precision oncology, there is a pressing need to understand the unique molecular drivers in uncommon histologic subtypes to facilitate genomically driven oncologic treatments.
Assuntos
Carcinoma Endometrioide/genética , Neoplasias Ovarianas/genética , Adulto , Idoso , Carcinoma Endometrioide/sangue , Carcinoma Endometrioide/patologia , Análise Mutacional de DNA , Feminino , Dosagem de Genes , Humanos , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/patologia , Sequenciamento do ExomaRESUMO
BACKGROUND: Cytomegalovirus (CMV) infection may complicate ulcerative colitis (UC) or Crohn's disease (CD) hospitalizations. Studies examining this relationship are often single-center examining short time periods. AIMS: To quantify the prevalence of CMV and its impact on outcomes among UC and CD hospitalizations over time using nationwide administrative databases. METHODS: The National Inpatient Sample and Nationwide Readmissions Database were analyzed to calculate CMV prevalence per 1000 UC and CD hospitalizations between 1998 and 2014. Univariable and multivariable logistic and linear regression were used to assess CMV's association with outcomes. Separate analyses examined effects from the introduction of anti-TNF therapy in UC in 2005, CD anatomic extent, and Clostridioides difficile infection. RESULTS: Among UC, from 1998 to 2014, the prevalence of CMV infection rose from 1.4 to 6.3 per 1000 UC hospitalizations (p < 0.001), although this increase was not statistically significant for the years 2006 to 2014 (p = 0.07). Among CD, prevalence rose from 0.3 to 1.8 per 1000 CD hospitalizations (p < 0.001) from 1998 to 2014. CMV was independently associated with increased inpatient mortality (UC: odds ratio (OR) 2.3, 95% confidence interval (CI) 1.2-4.5; CD: OR 4.6, CI 1.5-13.7), colectomy in UC (OR 2.5, CI 1.9-3.3), and higher length of stay and costs. CONCLUSION: CMV infection's prevalence among UC and CD hospitalizations is rising over time, but may have slowed after 2005 in UC. CMV is independently associated with increased inpatient mortality, length of stay, and hospital charges in UC and CD and with colectomy in UC.