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1.
Cell Rep ; 35(10): 109224, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34107252

RESUMO

Drug development is hampered by poor target selection. Phenotypic screens using neurons differentiated from patient stem cells offer the possibility to validate known and discover novel disease targets in an unbiased fashion. To identify targets for managing hyperexcitability, a pathological feature of amyotrophic lateral sclerosis (ALS), we design a multi-step screening funnel using patient-derived motor neurons. High-content live cell imaging is used to evaluate neuronal excitability, and from a screen against a chemogenomic library of 2,899 target-annotated compounds, 67 reduce the hyperexcitability of ALS motor neurons carrying the SOD1(A4V) mutation, without cytotoxicity. Bioinformatic deconvolution identifies 13 targets that modulate motor neuron excitability, including two known ALS excitability modulators, AMPA receptors and Kv7.2/3 ion channels, constituting target validation. We also identify D2 dopamine receptors as modulators of ALS motor neuron excitability. This screen demonstrates the power of human disease cell-based phenotypic screens for identifying clinically relevant targets for neurological disorders.


Assuntos
Esclerose Lateral Amiotrófica/genética , Diferenciação Celular , Humanos , Fenótipo
2.
Sci Total Environ ; 712: 135597, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31791787

RESUMO

In urbanized landscapes, green infrastructure is proposed as a method for using relatively small plots of land to manage stormwater and protect receiving ecosystems from pollutants. Bioretention cells can infiltrate stormwater from roads and parking lots, and as stormwater passed through the soils, metals can be removed. Metal removal and storage has been demonstrated in laboratory media columns and field-scale test cells, but we have an incomplete understanding of metal removal and accumulation in aging bioretention cells in the field. We surveyed 25 bioretention cells (0-7 years of service) for soil physicochemistry to determine which characteristics related to soil metal (Cu, Pb, and Zn) concentrations. We collected soil cores and treated them with simulated stormwater to measure potential rates of metal removal under different metal and salt concentrations. Older bioretention cells had higher Cu, Pb, and Zn concentrations in soil, which indicates accumulation and storage over time. The oldest cells had metal concentrations that were not a risk to human health but which approached screening thresholds for potential impairment of plants. Soil organic matter content (OM) was positively associated with metal concentrations which highlights the importance of OM in the functioning of cells. Retrofit bioretention cells were younger with less OM and more clay than cells built concurrently with new parking lot construction (i.e., de novo), but after 2.7 years of service, soil OM was similar between retrofit and de novo builds. Soil cores from de novo bioretention cells retained more stormwater metals than soil cores from retrofit cells, and this was likely due to differences in soil OM. Elevated road salt in stormwater was associated with less effective metal removal and leaching of Zn from soils. Overall, these data suggest that management (e.g., salting) and design (e.g., construction) decisions can greatly influence metal removal function of bioretention cells.


Assuntos
Ecossistema , Poluentes Ambientais , Metais , Plantas , Chuva , Solo
3.
Sci Data ; 6(1): 157, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31439840

RESUMO

A reference dataset of multi-wavelength particle light scattering and hemispheric backscattering coefficients for different relative humidities (RH) between RH = 30 and 95% and wavelengths between λ = 450 nm and 700 nm is described in this work. Tandem-humidified nephelometer measurements from 26 ground-based sites around the globe, covering multiple aerosol types, have been re-analysed and harmonized into a single dataset. The dataset includes multi-annual measurements from long-term monitoring sites as well as short-term field campaign data. The result is a unique collection of RH-dependent aerosol light scattering properties, presented as a function of size cut. This dataset is important for climate and atmospheric model-measurement inter-comparisons, as a means to improve model performance, and may be useful for satellite and remote sensing evaluation using surface-based, in-situ measurements.

6.
Bioorg Med Chem Lett ; 28(19): 3197-3201, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30170943

RESUMO

Utilizing the already described 3,4-bi-aryl pyridine series as a starting point, incorporation of a second ring system with a hydrogen bond donor and additional hydrophobic contacts yielded the azaindole series which exhibited potent, picomolar RSK2 inhibition and the most potent in vitro target modulation seen thus far for a RSK inhibitor. In the context of the more potent core, several changes at the phenol moiety were assessed to potentially find a tool molecule appropriate for in vivo evaluation.


Assuntos
Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Animais , Cromatografia Líquida , Desenho de Fármacos , Humanos , Espectrometria de Massas , Fenóis/farmacologia , Inibidores de Proteínas Quinases/química , Espectroscopia de Prótons por Ressonância Magnética , Relação Estrutura-Atividade
8.
Science ; 360(6385): 164, 2018 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-29650668
9.
Sci Data ; 4: 170003, 2017 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-28291234

RESUMO

Cloud condensation nuclei (CCN) number concentrations alongside with submicrometer particle number size distributions and particle chemical composition have been measured at atmospheric observatories of the Aerosols, Clouds, and Trace gases Research InfraStructure (ACTRIS) as well as other international sites over multiple years. Here, harmonized data records from 11 observatories are summarized, spanning 98,677 instrument hours for CCN data, 157,880 for particle number size distributions, and 70,817 for chemical composition data. The observatories represent nine different environments, e.g., Arctic, Atlantic, Pacific and Mediterranean maritime, boreal forest, or high alpine atmospheric conditions. This is a unique collection of aerosol particle properties most relevant for studying aerosol-cloud interactions which constitute the largest uncertainty in anthropogenic radiative forcing of the climate. The dataset is appropriate for comprehensive aerosol characterization (e.g., closure studies of CCN), model-measurement intercomparison and satellite retrieval method evaluation, among others. Data have been acquired and processed following international recommendations for quality assurance and have undergone multiple stages of quality assessment.

10.
Geohealth ; 1(10): 320-332, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32158979

RESUMO

Staphylococcus aureus can cause severe life-threatening illnesses such as sepsis and endocarditis. Although S. aureus has been isolated from marine water and intertidal beach sand, only a few studies have been conducted to assess prevalence of S. aureus at freshwater recreational beaches. As such, we aimed to determine prevalence and molecular characteristics of S. aureus in water and sand at 10 freshwater recreational beaches in Northeast Ohio, USA. Samples were analyzed using standard microbiology methods, and resulting isolates were typed by spa typing and multilocus sequence typing. The overall prevalence of S. aureus in sand and water samples was 22.8% (64/280). The prevalence of methicillin-resistant S. aureus (MRSA) was 8.2% (23/280). The highest prevalence was observed in summer (45.8%; 55/120) compared to fall (4.2%; 5/120) and spring (10.0%; 4/40). The overall prevalence of Panton-Valentine leukocidin genes among S. aureus isolates was 21.4% (15/70), and 27 different spa types were identified. The results of this study indicate that beach sand and freshwater of Northeast Ohio were contaminated with S. aureus, including MRSA. The high prevalence of S. aureus in summer months and presence of human-associated strains may indicate the possibility of role of human activity in S. aureus contamination of beach water and sand. While there are several possible routes for S. aureus contamination, S. aureus prevalence was higher in sites with wastewater treatment plants proximal to the beaches.

11.
Angew Chem Int Ed Engl ; 56(5): 1294-1297, 2017 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-27981705

RESUMO

CSN5 is the zinc metalloprotease subunit of the COP9 signalosome (CSN), which is an important regulator of cullin-RING E3 ubiquitin ligases (CRLs). CSN5 is responsible for the cleavage of NEDD8 from CRLs, and blocking deconjugation of NEDD8 traps the CRLs in a hyperactive state, thereby leading to auto-ubiquitination and ultimately degradation of the substrate recognition subunits. Herein, we describe the discovery of azaindoles as a new class of CSN5 inhibitors, which interact with the active-site zinc ion of CSN5 through an unprecedented binding mode. The best compounds inhibited CSN5 with nanomolar potency, led to degradation of the substrate recognition subunit Skp2 in cells, and reduced the viability of HCT116 cells.


Assuntos
Complexo do Signalossomo COP9/antagonistas & inibidores , Indóis/metabolismo , Zinco/metabolismo , Sítios de Ligação , Complexo do Signalossomo COP9/genética , Complexo do Signalossomo COP9/metabolismo , Domínio Catalítico , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Transferência Ressonante de Energia de Fluorescência , Células HCT116 , Humanos , Indóis/química , Indóis/farmacologia , Simulação de Acoplamento Molecular , Proteína NEDD8/química , Proteína NEDD8/metabolismo , Subunidades Proteicas/antagonistas & inibidores , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas Quinases Associadas a Fase S/química , Proteínas Quinases Associadas a Fase S/metabolismo , Zinco/química
12.
Environ Manage ; 59(4): 604-618, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27928585

RESUMO

Urbanization increases nutrient loading and lowers residence times for processing of reactive solutes, including nitrate, total dissolved nitrogen, orthophosphate, and dissolved organic carbon), which leads to increased stream concentrations and mass export. Stormwater control measures mitigate the impacts of urbanization, and have the potential to improve stream water quality, however the net effect instream is not well understood. We monitored two urban and two suburban watersheds in Charlotte, NC to determine if mitigation controlled the fraction of total mass export during storm, if development classification as either urban or suburban (defined by the age, density and distribution of urban development) controlled storm nutrient and carbon dynamics, and if stormwater control measures were able to change stream water chemistry. While average concentrations during stormflow were generally greater than baseflow, indicating that storms are important times of solute export, the fraction of storm-derived export was unrelated to mitigation by stormwater control measures. Development classification was generally not an important control on export of N and dissolved organic carbon. However, event mean concentrations of orthophosphate were higher at the suburban sites, possibly from greater fertilizer application. Stormwater control measures influenced instream water chemistry at only one site, which also had the greatest mitigated area, but differences between stormwater control measure outflow and stream water suggest the potential for water quality improvements. Together, results suggest stormwater control measures have the potential to decrease solute concentrations from urban runoff, but the type, location, and extent of urban development in the watershed may influence the magnitude of this effect.


Assuntos
Monitoramento Ambiental/métodos , Chuva , Rios/química , Urbanização , Poluentes Químicos da Água/análise , Qualidade da Água , Carbono/análise , Nitratos/análise , Nitrogênio/análise , North Carolina , Movimentos da Água
13.
Nat Commun ; 7: 13166, 2016 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-27774986

RESUMO

The COP9 signalosome (CSN) is a central component of the activation and remodelling cycle of cullin-RING E3 ubiquitin ligases (CRLs), the largest enzyme family of the ubiquitin-proteasome system in humans. CRLs are implicated in the regulation of numerous cellular processes, including cell cycle progression and apoptosis, and aberrant CRL activity is frequently associated with cancer. Remodelling of CRLs is initiated by CSN-catalysed cleavage of the ubiquitin-like activator NEDD8 from CRLs. Here we describe CSN5i-3, a potent, selective and orally available inhibitor of CSN5, the proteolytic subunit of CSN. The compound traps CRLs in the neddylated state, which leads to inactivation of a subset of CRLs by inducing degradation of their substrate recognition module. CSN5i-3 differentially affects the viability of tumour cell lines and suppresses growth of a human xenograft in mice. Our results provide insights into how CSN regulates CRLs and suggest that CSN5 inhibition has potential for anti-tumour therapy.


Assuntos
Antineoplásicos/farmacologia , Azepinas/farmacologia , Complexo do Signalossomo COP9/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Pirazóis/farmacologia , Ubiquitina-Proteína Ligases/genética , Animais , Antineoplásicos/síntese química , Azepinas/síntese química , Complexo do Signalossomo COP9/genética , Complexo do Signalossomo COP9/metabolismo , Feminino , Células HCT116 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/metabolismo , Linfoma Anaplásico de Células Grandes/patologia , Camundongos , Camundongos SCID , Terapia de Alvo Molecular , Proteína NEDD8/genética , Proteína NEDD8/metabolismo , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Processamento de Proteína Pós-Traducional , Proteólise/efeitos dos fármacos , Pirazóis/síntese química , Células THP-1 , Carga Tumoral/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Proc Natl Acad Sci U S A ; 113(21): 5828-34, 2016 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-26944081

RESUMO

Quantifying the aerosol/cloud-mediated radiative effect at a global scale requires simultaneous satellite retrievals of cloud condensation nuclei (CCN) concentrations and cloud base updraft velocities (Wb). Hitherto, the inability to do so has been a major cause of high uncertainty regarding anthropogenic aerosol/cloud-mediated radiative forcing. This can be addressed by the emerging capability of estimating CCN and Wb of boundary layer convective clouds from an operational polar orbiting weather satellite. Our methodology uses such clouds as an effective analog for CCN chambers. The cloud base supersaturation (S) is determined by Wb and the satellite-retrieved cloud base drop concentrations (Ndb), which is the same as CCN(S). Validation against ground-based CCN instruments at Oklahoma, at Manaus, and onboard a ship in the northeast Pacific showed a retrieval accuracy of ±25% to ±30% for individual satellite overpasses. The methodology is presently limited to boundary layer not raining convective clouds of at least 1 km depth that are not obscured by upper layer clouds, including semitransparent cirrus. The limitation for small solar backscattering angles of <25° restricts the satellite coverage to ∼25% of the world area in a single day.

15.
J Med Chem ; 58(17): 6766-83, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26270416

RESUMO

While the p90 ribosomal S6 kinase (RSK) family has been implicated in multiple tumor cell functions, the full understanding of this kinase family has been restricted by the lack of highly selective inhibitors. A bis-phenol pyrazole was identified from high-throughput screening as an inhibitor of the N-terminal kinase of RSK2. Structure-based drug design using crystallography, conformational analysis, and scaffold morphing resulted in highly optimized difluorophenol pyridine inhibitors of the RSK kinase family as demonstrated cellularly by the inhibition of YB1 phosphorylation. These compounds provide for the first time in vitro tools with an improved selectivity and potency profile to examine the importance of RSK signaling in cancer cells and to fully evaluate RSK as a therapeutic target.


Assuntos
Pirazóis/química , Piridinas/química , Pirimidinas/química , Proteínas Quinases S6 Ribossômicas 90-kDa/antagonistas & inibidores , Animais , Linhagem Celular , Cristalografia por Raios X , Humanos , Masculino , Camundongos , Modelos Moleculares , Fosforilação , Conformação Proteica , Pirazóis/síntese química , Pirazóis/farmacologia , Piridinas/síntese química , Piridinas/farmacologia , Pirimidinas/síntese química , Pirimidinas/farmacologia , Ratos Sprague-Dawley , Transdução de Sinais , Relação Estrutura-Atividade , Proteína 1 de Ligação a Y-Box/metabolismo
17.
Mol Cancer Res ; 12(5): 803-12, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24554780

RESUMO

UNLABELLED: The p90 ribosomal S6 kinase (RSK) family of serine/threonine kinases is expressed in a variety of cancers and its substrate phosphorylation has been implicated in direct regulation of cell survival, proliferation, and cell polarity. This study characterizes and presents the most selective and potent RSK inhibitors known to date, LJH685 and LJI308. Structural analysis confirms binding of LJH685 to the RSK2 N-terminal kinase ATP-binding site and reveals that the inhibitor adopts an unusual nonplanar conformation that explains its excellent selectivity for RSK family kinases. LJH685 and LJI308 efficiently inhibit RSK activity in vitro and in cells. Furthermore, cellular inhibition of RSK and its phosphorylation of YB1 on Ser102 correlate closely with inhibition of cell growth, but only in an anchorage-independent growth setting, and in a subset of examined cell lines. Thus, RSK inhibition reveals dynamic functional responses among the inhibitor-sensitive cell lines, underscoring the heterogeneous nature of RSK dependence in cancer. IMPLICATIONS: Two novel potent and selective RSK inhibitors will now allow a full assessment of the potential of RSK as a therapeutic target for oncology.


Assuntos
Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases S6 Ribossômicas 90-kDa/antagonistas & inibidores , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Sequência de Aminoácidos , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Modelos Moleculares , Dados de Sequência Molecular , Fosforilação
18.
J Neurointerv Surg ; 5(2): 139-43, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22266703

RESUMO

BACKGROUND: Despite increased recanalization rates in the treatment of acute ischemic stroke, the percentage of patients with a good clinical outcome of all those treated has not risen above 50%. This 50% barrier may be broken by improving the criteria for treatment selection. This study investigated the addition of the capillary index score (CIS), a new index for assessing remaining viable tissue in the ischemic area, to the existing criteria. METHODS: The Borgess Medical Center Ischemic Stroke Registry is a non-randomized single-center single-operator registry of consecutive subjects admitted for intra-arterial treatment of acute ischemic stroke. The CIS was calculated from a pre-intervention catheter cerebral angiogram in subjects with internal carotid artery (ICA) or middle cerebral artery (MCA) (M1) occlusion. Thrombolysis In Myocardial Infarction (TIMI) 2 or 3 was considered successful recanalization. A modified Rankin Scale (mRS) of 0-2 at 3 months was considered a good outcome. RESULTS: ICA or MCA (M1) occlusion was found in 46 of 58 consecutive patients treated by the same operator. Recanalization was successful in 72% of patients and 27% had a good outcome. CIS was available for 26 patients; 42% were favorable (2 or 3) and 58% were poor (0 or 1). A good outcome was found only in the favorable CIS group (p=0.0148). Successful recanalization (p=0.0029) and time from ictus to revascularization (p=0.0039) predicted a good outcome. Of patients with favorable CIS and TIMI 3, 83% had a good outcome. CONCLUSIONS: Favorable CIS and recanalization were strong predictors of a good outcome. By using this new index as an adjunct to other criteria, the CIS may improve patient selection and help break the 50% barrier.


Assuntos
Centros Médicos Acadêmicos , Algoritmos , Isquemia Encefálica/diagnóstico por imagem , Capilares/diagnóstico por imagem , Sistema de Registros , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico por imagem , Centros Médicos Acadêmicos/normas , Idoso , Isquemia Encefálica/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Sistema de Registros/normas , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento
19.
Stroke ; 42(9): 2544-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21778441

RESUMO

BACKGROUND AND PURPOSE: Although atherosclerotic plaque in the carotid and coronary arteries is accepted as a cause of ischemia, vertebral artery ostium (VAO) atherosclerotic plaque is not widely recognized as a source of ischemic stroke. We seek to demonstrate its implication in some posterior circulation ischemia. METHODS: This is a nonrandomized, prospective, single-center registry on consecutive patients presenting with posterior circulation ischemia who underwent VAO stenting for significant atherosclerotic stenosis. Diagnostic evaluation and imaging studies determined the likelihood of this lesion as the symptom source (highly likely, probable, or highly unlikely). Patients were divided into 4 groups in decreasing order of severity of clinical presentation (ischemic stroke, TIA then stroke, TIA, asymptomatic), which were compared with the morphological and hemodynamic characteristics of the VAO plaque. Clinical follow-up 1 year after stenting assessed symptom recurrence. RESULTS: One hundred fourteen patients underwent stenting of 127 lesions; 35% of the lesions were highly likely the source of symptoms, 53% were probable, and 12% were highly unlikely. Clinical presentation correlated directly with plaque irregularity and presence of clot at the VAO, as did bilateral lesions and presence of tandem lesions. Symptom recurrence at 1 year was 2%. CONCLUSIONS: Thirty-five percent of the lesions were highly likely the source of the symptoms. A direct relationship between some morphological/hemodynamic characteristics and the severity of clinical presentation was also found. Finally, patients had a very low rate of symptom recurrence after treatment. These 3 observations point strongly to VAO plaque as a potential source of some posterior circulation stroke.


Assuntos
Hemodinâmica , Arteriosclerose Intracraniana/fisiopatologia , Sistema de Registros , Acidente Vascular Cerebral , Artéria Vertebral/fisiopatologia , Insuficiência Vertebrobasilar , Idoso , Feminino , Seguimentos , Humanos , Arteriosclerose Intracraniana/complicações , Masculino , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/fisiopatologia , Insuficiência Vertebrobasilar/complicações , Insuficiência Vertebrobasilar/fisiopatologia
20.
Health Educ Res ; 23(2): 359-68, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17884834

RESUMO

This paper examines factors associated with high levels of recruitment and retention of youth into smoking cessation interventions. Fifty-five articles published from 1976 to June 2004 reported cessation outcomes were analyzed to examine the associations between selected variables and recruitment and retention rates. Studies with participants who smoked < or =5 cigarettes per day (cpd) were more likely to have recruitment rates > or =85%. Yet, studies with participants who smoked > or =6 cpd were more likely to have high retention rates. Studies that did not use incentives were more likely to have retention rates at end of intervention > or =85%. Findings indicate a lack of information reported about recruitment and retention procedures in adolescent tobacco cessation studies. Additional analyses and research need to be conducted to identify successful methods.


Assuntos
Comportamento do Adolescente , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Seleção de Pacientes , Abandono do Hábito de Fumar/métodos , Adolescente , Humanos
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