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1.
J Aerosol Sci ; 159: 1-31, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35530659

RESUMEN

There is no universally agreed upon definition for ultrafine particles (UFP). Commonly used definitions for UFP are either particle number below 100 nm or total particle number, but without an agreed upon lower cut point. For example, a lower cut point of 3 nm compared to 10 nm could result in a substantially higher count. Another definition for UFP is total particle mass but without a commonly agreed upon aerodynamic diameter upper cut point, e.g., below 100 nm, 200 nm, 300 nm, etc. Yet another definition is lung deposited surface area weighted by lung deposition fraction, found mainly in the particle mobility diameter range from 20 to 400 nm. It is clear from these definitions that there are inconsistencies in the way UFP is used and defined in the literature. Sometimes these metrics are well correlated, sometimes not. In this paper we suggest three exposure metrics: UFP-N, UFP-M, and UFP-S, that we believe will add clarity. These metrics represent total number, mass, and surface area below 500 nm, respectively. For surface area and mass, the 500 nm cut point can be either aerodynamic or mobility diameter depending upon measurement methodology. For all metrics, this cut point captures nearly all of the primary particle emissions from mobile sources. Furthermore, UFP-N would include a lower cut point of 3-6 nm and would not require an upper size cut point because there is very little particle number above 500 nm or even above 100 nm. Thus, our definition of UFP-N is consistent with the current definition of ultrafine number except for, importantly, the specification of a lower cut point. These exposure metrics can help facilitate consistency in the characterization of both short- and long-term UFP ambient exposures and associated health effects in epidemiological studies.

3.
Acad Pediatr ; 22(8): 1265-1270, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35172199

RESUMEN

OBJECTIVE: To determine whether a musculoskeletal curriculum involving gamification via Kahoot! (an online classroom response system) was acceptable and more effective at teaching pediatric residents musculoskeletal knowledge and skills than a nongamified curriculum. METHODS: A prospective, randomized controlled trial was conducted at an urban, academic pediatric clinic. All participants received a curriculum that included brief didactics and knowledge questions. The knowledge questions were delivered via Kahoot! to the intervention group and administered via paper to the control group. The primary outcome was knowledge and skill acquisition following curriculum participation. RESULTS: A total of 73 of 85 (86%) residents completed the study (intervention group: 46; control group: 27). Following participation in the curriculum, intervention and control residents demonstrated an improvement in musculoskeletal knowledge (P < .05) measured via questionnaire, as well as an improvement in physical exam skills during a standardized patient encounter (P < .05). There was no difference in knowledge or skill improvement between groups. Intervention participants indicated positive attitudes toward Kahoot!. CONCLUSIONS: Our musculoskeletal curriculum demonstrated improvements in knowledge and skills among residents, though inclusion of Kahoot! did not enhance the experimental effect. Further research is needed to identify strategies to optimize gamification for learning.


Asunto(s)
Internado y Residencia , Humanos , Niño , Estudios Prospectivos , Curriculum , Examen Físico , Aprendizaje , Competencia Clínica
4.
Transl Res ; 249: 49-73, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35691544

RESUMEN

As an anti-inflammatory strategy, MAPK-activated protein kinase-2 (MK2) inhibition can potentially avoid the clinical failures seen for direct p38 inhibitors, especially tachyphylaxis. CC-99677, a selective targeted covalent MK2 inhibitor, employs a rare chloropyrimidine that bonds to the sulfur of cysteine 140 in the ATP binding site via a nucleophilic aromatic substitutions (SNAr) mechanism. This irreversible mechanism translates biochemical potency to cells shown by potent inhibition of heat shock protein 27 (HSP27) phosphorylation in LPS-activated monocytic THP-1 cells. The cytokine inhibitory profile of CC-99677 differentiates it from known p38 inhibitors, potentially suppressing a p38 pathway inflammatory response while avoiding tachyphylaxis. Dosed orally, CC-99677 is efficacious in a rat model of ankylosing spondylitis. Single doses, 3 to 400 mg, in healthy human volunteers show linear pharmacokinetics and apparent sustained tumor necrosis factor-α inhibition, with a favorable safety profile. These results support further development of CC-99677 for autoimmune diseases like ankylosing spondylitis.


Asunto(s)
Enfermedades Autoinmunes , Espondilitis Anquilosante , Adenosina Trifosfato , Animales , Antiinflamatorios , Enfermedades Autoinmunes/tratamiento farmacológico , Cisteína , Proteínas de Choque Térmico HSP27/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Lipopolisacáridos , Proteínas Serina-Treonina Quinasas , Ratas , Azufre , Factor de Necrosis Tumoral alfa , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
5.
Arthritis Care Res (Hoboken) ; 74(3): 355-363, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-33085849

RESUMEN

OBJECTIVE: The Effects of Youngsters' Eyesight on Quality of Life (EYE-Q) questionnaire measures vision-related functioning (VRF) and vision-related quality of life (VRQoL) in children with uveitis. Our aim was to revise the alpha version of the EYE-Q to refine VRF and VRQoL subscales and to assess the validity of the EYE-Q. METHODS: Children with juvenile idiopathic arthritis (JIA), JIA-associated uveitis, and other noninfectious uveitis were enrolled. Patients and parents completed the EYE-Q, Pediatric Quality of Life Inventory (overall quality of life), and Childhood Health Assessment Questionnaire (physical functioning). The development site completed the alpha version of the EYE-Q, and the composite sites completed the beta version. We compared item-subscale correlations, internal consistency, and construct and discriminant validity among the different versions. RESULTS: Of the 644 patients enrolled, 61.6% completed the alpha version, and 38.4% the beta version of the EYE-Q. Mean ± SD patient age was 11.1 ± 4.2 years, and 70% were female. Fewer White patients (73.5%) completed the alpha version compared to the beta version (86.2%; P < 0.001). With the exception of patient-reported VRF, both versions had similar item-subscale correlations. Version comparisons on scale internal consistencies indicated significant differences for parent- and patient-reported VRF, but each scale had a Cronbach's α of >0.80 beta. When data were combined, the EYE-Q showed significant differences between JIA-only and uveitis patients on all parent and patient scores, except for patient-reported VRF. CONCLUSION: The EYE-Q appears to be a valid measure of VRF and VRQoL in pediatric uveitis. Our results suggest it may be used as an outcome measure in multicenter pediatric uveitis studies.


Asunto(s)
Calidad de Vida , Encuestas y Cuestionarios/normas , Uveítis/psicología , Adolescente , Artritis Juvenil/complicaciones , Niño , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Uveítis/etiología
6.
Arthritis Care Res (Hoboken) ; 74(8): 1311-1320, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-33421338

RESUMEN

OBJECTIVE: Pediatric uveitis can lead to sight-threatening complications and can impact quality of life (QoL) and functioning. We aimed to examine health-related QoL, mental health, physical disability, vision-related functioning (VRF), and vision-related QoL in children with juvenile idiopathic arthritis (JIA), JIA-associated uveitis (JIA-U), and other noninfectious uveitis. We hypothesized that there will be differences based on the presence of eye disease. METHODS: A multicenter cross-sectional study was conducted at four sites. Patients with JIA, JIA-U, or noninfectious uveitis were enrolled. Patients and parents completed the Pediatric Quality of Life Inventory (PedsQL; health-related QoL), the Revised Childhood Anxiety and Depression Scale (RCADS; anxiety/depression), the Childhood Health Assessment Questionnaire (C-HAQ; physical disability), and the Effects of Youngsters' Eyesight on Quality of Life (EYE-Q) (VRF/vision-related QoL). Clinical characteristics and patient-reported outcome measures were compared by diagnosis. RESULTS: Of 549 patients, 332 had JIA, 124 had JIA-U, and 93 had other uveitis diagnoses. Children with JIA-U had worse EYE-Q scores compared to those with JIA only. In children with uveitis, those with anterior uveitis (JIA-U and uveitis only) had less ocular complications, better EYE-Q scores, and worse C-HAQ and PedsQL physical summary scores compared to those with nonanterior disease. In children with anterior uveitis, those with JIA-U had worse PedsQL physical summary and C-HAQ scores than anterior uveitis only. Further, EYE-Q scores were worse in children with bilateral uveitis and more visual impairment. There were no differences in RCADS scores among groups. CONCLUSION: We provide a comprehensive outcome assessment of children with JIA, JIA-U, and other uveitis diagnoses. Differences in QoL and function were noted based on underlying disease. Our results support the addition of a vision-specific measure to better understand the impact of uveitis.


Asunto(s)
Artritis Juvenil , Uveítis Anterior , Uveítis , Artritis Juvenil/complicaciones , Artritis Juvenil/diagnóstico , Artritis Juvenil/psicología , Niño , Estudios Transversales , Humanos , Salud Mental , Calidad de Vida/psicología , Uveítis/diagnóstico , Uveítis/epidemiología , Uveítis/etiología , Uveítis Anterior/diagnóstico
7.
Bioorg Med Chem Lett ; 21(21): 6545-53, 2011 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-21924613

RESUMEN

Fatty acid amide hydrolase (FAAH) is an integral membrane serine hydrolase responsible for the degradation of fatty acid amide signaling molecules such as endocannabinoid anandamide (AEA), which has been shown to possess cannabinoid-like analgesic properties. Herein we report the optimization of spirocyclic 7-azaspiro[3.5]nonane and 1-oxa-8-azaspiro[4.5]decane urea covalent inhibitors of FAAH. Using an iterative design and optimization strategy, lead compounds were identified with a remarkable reduction in molecular weight and favorable CNS drug like properties. 3,4-Dimethylisoxazole and 1-methyltetrazole were identified as superior urea moieties for this inhibitor class. A dual purpose in vivo efficacy and pharmacokinetic screen was designed to be the key decision enabling experiment affording the ability to move quickly from compound synthesis to selection of preclinical candidates. On the basis of the remarkable potency, selectivity, pharmacokinetic properties and in vivo efficacy, PF-04862853 (15p) was advanced as a clinical candidate.


Asunto(s)
Amidohidrolasas/antagonistas & inhibidores , Analgésicos/farmacología , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Dolor/tratamiento farmacológico , Compuestos de Espiro/farmacología , Administración Oral , Analgésicos/administración & dosificación , Analgésicos/química , Analgésicos/uso terapéutico , Animales , Compuestos Aza/administración & dosificación , Compuestos Aza/química , Compuestos Aza/farmacología , Compuestos Aza/uso terapéutico , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/uso terapéutico , Ratas , Compuestos de Espiro/administración & dosificación , Compuestos de Espiro/química , Compuestos de Espiro/uso terapéutico
8.
Bioorg Med Chem Lett ; 21(21): 6538-44, 2011 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-21924614

RESUMEN

Herein we report the identification of two new fatty acid amide hydrolase (FAAH) inhibitor lead series with FAAH k(inact)/K(i) potency values greater than 1500M(-1)s(-1). The two novel spirocyclic cores, 7-azaspiro[3.5]nonane and 1-oxa-8-azaspiro[4.5]decane, clearly distinguished themselves from the other spirocyclic cores on the basis of their superior potency for FAAH. Lead compounds from these two series have suitable FAAH potency and selectivity for additional medicinal chemistry optimization.


Asunto(s)
Amidohidrolasas/antagonistas & inhibidores , Compuestos Aza/farmacología , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Compuestos de Espiro/farmacología , Compuestos Aza/química , Inhibidores Enzimáticos/química , Modelos Moleculares , Compuestos de Espiro/química , Relación Estructura-Actividad
9.
Environ Sci Technol ; 45(15): 6420-8, 2011 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-21718041

RESUMEN

Exhaust emissions of 17 2,3,7,8-substituted chlorinated dibenzo-p-dioxin/furan (CDD/F) congeners, tetra-octa CDD/F homologues, 12 2005 WHO chlorinated biphenyls (CB) congeners, mono-nona CB homologues, and 19 polycyclic aromatic hydrocarbons (PAHs) from a model year 2008 Cummins ISB engine were investigated. Testing included configurations composed of different combinations of aftertreatment including a diesel oxidation catalyst (DOC), catalyzed diesel particulate filter (CDPF), copper zeolite urea selective catalytic reduction (SCR), iron zeolite SCR, and ammonia slip catalyst. Results were compared to a baseline engine out configuration. Testing included the use of fuel that contained the maximum expected chlorine (Cl) concentration of U.S. highway diesel fuel and a Cl level 1.5 orders of magnitude above. Results indicate there is no risk for an increase in polychlorinated dibenzo-p-dioxin/furan and polychlorinated biphenyl emissions from modern diesel engines with catalyzed aftertreatment when compared to engine out emissions for configurations tested in this program. These results, along with PAH results, compare well with similar results from modern diesel engines in the literature. The results further indicate that polychlorinated dibenzo-p-dioxin/furan emissions from modern diesel engines both with and without aftertreatment are below historical values reported in the literature as well as the current inventory value.


Asunto(s)
Gasolina/análisis , Vehículos a Motor , Bifenilos Policlorados/análisis , Dibenzodioxinas Policloradas/análogos & derivados , Hidrocarburos Policíclicos Aromáticos/análisis , Emisiones de Vehículos/prevención & control , Catálisis , Bifenilos Policlorados/química , Bifenilos Policlorados/toxicidad , Dibenzodioxinas Policloradas/análisis , Dibenzodioxinas Policloradas/química , Dibenzodioxinas Policloradas/toxicidad , Hidrocarburos Policíclicos Aromáticos/química , Hidrocarburos Policíclicos Aromáticos/toxicidad , Temperatura , Emisiones de Vehículos/análisis , Organización Mundial de la Salud
10.
Pediatr Rheumatol Online J ; 19(1): 73, 2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-34001167

RESUMEN

BACKGROUND: Childhood-onset systemic lupus erythematosus (cSLE) is a complex autoimmune disorder with multi-organ manifestations and can be associated with other rheumatic diseases including Sjögren's syndrome (SS). Salivary gland ultrasound (SGUS) represents a noninvasive tool to screen for salivary gland disease in rheumatic disease patients. The aims of this cross-sectional study were to determine feasibility of major SGUS in a clinic setting and to identify characteristics in a cohort of cSLE patients (without confirmed SS) that may be associated with salivary gland abnormalities consistent with secondary SS. METHODS: Patients with SLE onset prior to age 18 were recruited. Patients completed questionnaires rating symptoms and underwent major SGUS examination. Disease and demographic differences were compared between cSLE patients with abnormal SGUS vs. cSLE patients with normal SGUS using t-tests and Fisher's exact tests. RESULTS: Thirty-one cSLE patients were recruited, 84% were female, 55% were Caucasian. The average disease duration among all patients was 5 years. Average time to complete the SGUS examination and scoring protocol was 7 min. 35% of SGUS scores were abnormal and significantly associated with IgG level at diagnosis, and anti-Ro and anti-La antibodies. CONCLUSIONS: This is one of the first studies to our knowledge that assesses major SGUS in a cohort of patients with cSLE without prior diagnoses of SS. The SGUS protocol was feasible to perform by rheumatologists in a clinic setting. Although the sample size was small, SGUS abnormalities were identified in one-third of patients. IgG level at diagnosis and anti-Ro and anti-La antibodies may be associated with SGUS abnormalities.


Asunto(s)
Antirreumáticos , Lupus Eritematoso Sistémico , Glándulas Salivales/diagnóstico por imagen , Síndrome de Sjögren , Ultrasonografía/métodos , Adolescente , Edad de Inicio , Anticuerpos Antinucleares/aislamiento & purificación , Antirreumáticos/clasificación , Antirreumáticos/uso terapéutico , Estudios Transversales , Estudios de Factibilidad , Femenino , Humanos , Inmunoglobulina G/sangre , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/epidemiología , Lupus Eritematoso Sistémico/inmunología , Masculino , Medición de Resultados Informados por el Paciente , Síndrome de Sjögren/diagnóstico , Síndrome de Sjögren/epidemiología , Síndrome de Sjögren/inmunología , Estados Unidos/epidemiología
11.
Bioorg Med Chem Lett ; 20(12): 3561-4, 2010 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-20529685

RESUMEN

A series of N-aryl isonipecotamide alpha-sulfone hydroxamate derivatives has been prepared utilizing a combination of solution-phase and resin-bound library technologies to afford compounds that are potent and highly selective for MMP-13.


Asunto(s)
Ácidos Hidroxámicos/química , Inhibidores de la Metaloproteinasa de la Matriz , Administración Oral , Amidas , Animales , Ácidos Hidroxámicos/síntesis química , Ácidos Hidroxámicos/farmacología , Concentración 50 Inhibidora , Ratas , Bibliotecas de Moléculas Pequeñas , Solubilidad , Especificidad por Sustrato , Sulfonas
12.
Bioorg Med Chem Lett ; 20(12): 3557-60, 2010 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-20529684

RESUMEN

A series of phenyl piperidine alpha-sulfone hydroxamate derivatives has been prepared utilizing a combination of solution-phase and resin-bound library technologies to afford compounds that are potent and highly selective for MMP-13, are dual-sparing of MMP-1 and MMP-14 (MT1-MMP) and exhibit oral bioavailability in rats.


Asunto(s)
Inhibidores de la Metaloproteinasa de la Matriz , Administración Oral , Animales , Disponibilidad Biológica , Ácidos Hidroxámicos/administración & dosificación , Metaloproteinasa 1 de la Matriz/efectos de los fármacos , Metaloproteinasa 14 de la Matriz/efectos de los fármacos , Piperidinas , Ratas , Bibliotecas de Moléculas Pequeñas , Solubilidad , Especificidad por Sustrato , Sulfonas
13.
Bioorg Med Chem Lett ; 20(2): 576-80, 2010 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-20005097

RESUMEN

Potent, highly selective and orally-bioavailable MMP-13 inhibitors have been identified based upon a (pyridin-4-yl)-2H-tetrazole scaffold. Co-crystal structure analysis revealed that the inhibitors bind at the S(1)(') active site pocket and are not ligands for the catalytic zinc atom. Compound 29b demonstrated reduction of cartilage degradation biomarker (TIINE) levels associated with cartilage protection in a preclinical rat osteoarthritis model.


Asunto(s)
Inhibidores de la Metaloproteinasa de la Matriz , Osteoartritis/tratamiento farmacológico , Ácidos Picolínicos/química , Inhibidores de Proteasas/química , Tetrazoles/química , Administración Oral , Animales , Sitios de Unión , Cartílago/efectos de los fármacos , Cartílago/metabolismo , Dominio Catalítico , Cristalografía por Rayos X , Modelos Animales de Enfermedad , Descubrimiento de Drogas , Metaloproteinasa 13 de la Matriz/metabolismo , Ácidos Picolínicos/síntesis química , Ácidos Picolínicos/farmacología , Inhibidores de Proteasas/síntesis química , Inhibidores de Proteasas/farmacología , Ratas , Tetrazoles/síntesis química , Tetrazoles/farmacología , Zinc/química
14.
Nat Struct Mol Biol ; 27(4): 319-322, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32251415

RESUMEN

Thalidomide-dependent degradation of the embryonic transcription factor SALL4 by the CRL4CRBN E3 ubiquitin ligase is a plausible major driver of thalidomide teratogenicity. The structure of the second zinc finger of SALL4 in complex with pomalidomide, cereblon and DDB1 reveals the molecular details of recruitment. Sequence differences and a shifted binding position relative to Ikaros offer a path to the rational design of cereblon-binding drugs with reduced teratogenic risk.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/química , Proteínas de Unión al ADN/ultraestructura , Complejos Multiproteicos/ultraestructura , Factores de Transcripción/ultraestructura , Proteínas Adaptadoras Transductoras de Señales/genética , Cristalografía por Rayos X , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Humanos , Complejos Multiproteicos/química , Complejos Multiproteicos/genética , Unión Proteica , Conformación Proteica , Proteolisis/efectos de los fármacos , Especificidad por Sustrato , Talidomida/análogos & derivados , Talidomida/química , Talidomida/farmacología , Factores de Transcripción/química , Factores de Transcripción/genética , Ubiquitina-Proteína Ligasas/química , Ubiquitina-Proteína Ligasas/ultraestructura , Ubiquitinación/genética
15.
ACS Med Chem Lett ; 11(10): 1899-1904, 2020 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-33062171

RESUMEN

Hepatocellular carcinoma (HCC) accounts for a majority of primary liver cancer and is one of the most common forms of cancer worldwide. Aberrant signaling of the FGF19-FGFR4 pathway leads to HCC in mice and is hypothesized to be a driver in FGF19 amplified HCC in humans. Multiple small molecule inhibitors have been pursued as targeted therapies for HCC in recent years, including several selective FGFR4 inhibitors that are currently being evaluated in clinical trials. Herein, we report a novel series of highly selective, covalent 2-amino-6,8-dimethyl-pyrido[2,3-d]pyrimidin-7(8H)-ones that potently and selectively inhibit FGFR4 signaling through covalent modification of Cys552, which was confirmed by X-ray crystallography. Correlative target occupancy and pFGFR4 inhibition were observed in vivo, as well as tumor regression in preclinical models of orthotopic and sorafenib-resistant HCC.

16.
Bioorg Med Chem Lett ; 19(20): 5970-4, 2009 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-19765986

RESUMEN

Fatty acid amide hydrolase (FAAH) has attracted significant attention due to its promise as an analgesic target. This has resulted in the discovery of numerous chemical classes as inhibitors of this potential therapeutic target. In this paper we disclose a new series of novel FAAH irreversible azetidine urea inhibitors. In general these compounds illustrate potent activity against the rat FAAH enzyme. Our SAR studies allowed us to optimize this series resulting in the identification of compounds 13 which were potent inhibitors of both human and rat enzyme. This series of compounds illustrated good hydrolase selectivity along with good PK properties.


Asunto(s)
Amidohidrolasas/antagonistas & inhibidores , Analgésicos/química , Azetidinas/química , Inhibidores Enzimáticos/química , Piridazinas/química , Urea/química , Amidohidrolasas/metabolismo , Analgésicos/síntesis química , Analgésicos/farmacocinética , Animales , Azetidinas/síntesis química , Azetidinas/farmacocinética , Sitios de Unión , Cristalografía por Rayos X , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacocinética , Humanos , Piridazinas/síntesis química , Piridazinas/farmacocinética , Ratas , Relación Estructura-Actividad , Urea/síntesis química , Urea/farmacocinética
17.
J Comput Aided Mol Des ; 23(1): 13-24, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18777160

RESUMEN

Inducible, microsomal prostaglandin E synthase 1 (mPGES-1), the terminal enzyme in the prostaglandin (PG) biosynthetic pathway, constitutes a promising therapeutic target for the development of new anti-inflammatory drugs. To elucidate structure-function relationships and to enable structure-based design, an mPGES-1 homology model was developed using the three-dimensional structure of the closest homologue of the MAPEG family (Membrane Associated Proteins in Eicosanoid and Glutathione metabolism), mGST-1. The ensuing model of mPGES-1 is a homo-trimer, with each monomer consisting of four membrane-spanning segments. Extensive structure refinement revealed an inter-monomer salt bridge (K26-E77) as well as inter-helical interactions within each monomer, including polar hydrogen bonds (e.g. T78-R110-T129) and hydrophobic pi-stacking (F82-F103-F106), all contributing to the overall stability of the homo-trimer of mPGES-1. Catalytic co-factor glutathione (GSH) was docked into the mPGES-1 model by flexible optimization of both the ligand and the protein conformations, starting from the initial location ascertained from the mGST-1 structure. Possible binding site for the substrate, prostaglandin H(2) (PGH(2)), was identified by systematically probing the refined molecular structure of mPGES-1. A binding model was generated by induced fit docking of PGH(2) in the presence of GSH. The homology model prescribes three potential inhibitor binding sites per mPGES-1 trimer. This was further confirmed experimentally by equilibrium dialysis study which generated a binding stoichiometric ratio of approximately three inhibitor molecules to three mPGES-1 monomers. The structural model that we have derived could serve as a useful tool for structure-guided design of inhibitors for this emergently important therapeutic target.


Asunto(s)
Inhibidores Enzimáticos/química , Oxidorreductasas Intramoleculares/química , Microsomas/enzimología , Secuencia de Aminoácidos , Biopolímeros , Inhibidores Enzimáticos/farmacología , Humanos , Oxidorreductasas Intramoleculares/antagonistas & inhibidores , Oxidorreductasas Intramoleculares/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Prostaglandina-E Sintasas , Conformación Proteica , Homología de Secuencia de Aminoácido
18.
SAE Int J Adv Curr Pract Mobil ; 1(2): 601-638, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32803170

RESUMEN

As part of the U.S. Environmental Protection Agency's (EPA's) continuing assessment of advanced light-duty automotive technologies in support of regulatory and compliance programs, a 2018 Toyota Camry A25A-FKS 4-cylinder, 2.5-liter, naturally aspirated, Atkinson Cycle engine with cooled exhaust gas recirculation (cEGR) was benchmarked. The engine was tested on an engine dynamometer with and without its 8-speed automatic transmission, and with the engine wiring harness tethered to a complete vehicle parked outside of the test cell. Engine and transmission torque, fuel flow, key engine temperatures and pressures, onboard diagnostics (OBD) data, and Controller Area Network (CAN) bus data were recorded. This paper documents the test results under idle, low, medium, and high load engine operation. Motoring torque, wide open throttle (WOT) torque and fuel consumption are measured during transient operation using both EPA Tier 2 and Tier 3 test fuels. The design and performance of this 2018 2.5-liter engine is described and compared to Toyota's published data and to EPA's previous projections of the efficiency of an Atkinson Cycle engine with cEGR. The Brake Thermal Efficiency (BTE) map for the Toyota A25A-FKS engine shows a peak efficiency near 40 percent, which is the highest value of any publicly available map for a non-hybrid production gasoline internal combustion (IC) engine designed to run on 91 RON fuel. Further improvement is possible by application of fixed discrete or full continuous cylinder deactivation, both of which are currently in production on other engines.

19.
ACS Med Chem Lett ; 10(12): 1592-1602, 2019 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-31857833

RESUMEN

Many cellular processes and pathways are mediated by the regulation of protein-protein complexes. For example, E3 ubiquitin ligases recruit substrate proteins and transfer a ubiquitin tag to target those proteins for destruction by the proteasome. It has now been shown that this cellular process for protein destruction can be redirected by small molecules in both laboratory and clinical settings. This presents a new paradigm in drug discovery, enabling the rapid removal of target proteins linked to disease. In this Innovations review, we will describe the work done on cereblon as a case study on the different strategies available for targeted protein degradation.

20.
SAE Int J Engines ; 11(6): 1273-1305, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-31275509

RESUMEN

As part of the U.S. Environmental Protection Agency's (EPA's) continuing assessment of advanced light-duty automotive technologies to support the setting of appropriate national greenhouse gas standards and to evaluate the impact of new technologies on in- use emissions, a 2016 Honda Civic with a 4-cylinder 1.5-liter L15B7 turbocharged engine and continuously variable transmission (CVT) was benchmarked. The test method involved installing the engine and its CVT in an engine dynamometer test cell with the engine wiring harness tethered to its vehicle parked outside the test cell. Engine and transmission torque, fuel flow, key engine temperatures and pressures, and onboard diagnostics (OBD)/CAN bus data were recorded. This paper documents the test results for idle, low, medium and high load engine operation, as well as motoring torque, wide-open throttle torque and fuel consumption during transient operation using both EPA Tier 2 and Tier 3 test fuels. Particular attention is given to characterizing enrichment control during high load engine operation. Results are used to create complete engine fuel consumption and efficiency maps and estimate CO2 emissions using EPA's ALPHA full vehicle simulation model, over regulatory drive cycles. The design and performance of the 1.5-liter Honda engine are compared to several other past, present, and future downsized-boosted engines and potential advancements are evaluated.

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