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1.
Nat Immunol ; 18(7): 813-823, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28530713

RESUMEN

The transcriptional programs that guide lymphocyte differentiation depend on the precise expression and timing of transcription factors (TFs). The TF BACH2 is essential for T and B lymphocytes and is associated with an archetypal super-enhancer (SE). Single-nucleotide variants in the BACH2 locus are associated with several autoimmune diseases, but BACH2 mutations that cause Mendelian monogenic primary immunodeficiency have not previously been identified. Here we describe a syndrome of BACH2-related immunodeficiency and autoimmunity (BRIDA) that results from BACH2 haploinsufficiency. Affected subjects had lymphocyte-maturation defects that caused immunoglobulin deficiency and intestinal inflammation. The mutations disrupted protein stability by interfering with homodimerization or by causing aggregation. We observed analogous lymphocyte defects in Bach2-heterozygous mice. More generally, we observed that genes that cause monogenic haploinsufficient diseases were substantially enriched for TFs and SE architecture. These findings reveal a previously unrecognized feature of SE architecture in Mendelian diseases of immunity: heterozygous mutations in SE-regulated genes identified by whole-exome/genome sequencing may have greater significance than previously recognized.


Asunto(s)
Enfermedades Autoinmunes/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Síndromes de Inmunodeficiencia/genética , Corticoesteroides/uso terapéutico , Adulto , Enfermedades Autoinmunes/complicaciones , Colitis/complicaciones , Colitis/genética , Colitis/patología , Femenino , Fiebre/complicaciones , Fiebre/tratamiento farmacológico , Fiebre/genética , Haploinsuficiencia , Heterocigoto , Humanos , Síndromes de Inmunodeficiencia/complicaciones , Linfopenia/complicaciones , Linfopenia/genética , Masculino , Persona de Mediana Edad , Mutación , Pancitopenia/complicaciones , Pancitopenia/tratamiento farmacológico , Pancitopenia/genética , Linaje , Polimorfismo de Nucleótido Simple , Recurrencia , Infecciones del Sistema Respiratorio/complicaciones , Infecciones del Sistema Respiratorio/diagnóstico por imagen , Infecciones del Sistema Respiratorio/genética , Esplenomegalia/complicaciones , Esplenomegalia/genética , Síndrome , Tomografía Computarizada por Rayos X , Adulto Joven
2.
Nature ; 534(7608): 529-33, 2016 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-27281223

RESUMEN

Polymer cold-drawing is a process in which tensile stress reduces the diameter of a drawn fibre (or thickness of a drawn film) and orients the polymeric chains. Cold-drawing has long been used in industrial applications, including the production of flexible fibres with high tensile strength such as polyester and nylon. However, cold-drawing of a composite structure has been less studied. Here we show that in a multimaterial fibre composed of a brittle core embedded in a ductile polymer cladding, cold-drawing results in a surprising phenomenon: controllable and sequential fragmentation of the core to produce uniformly sized rods along metres of fibre, rather than the expected random or chaotic fragmentation. These embedded structures arise from mechanical-geometric instabilities associated with 'neck' propagation. Embedded, structured multimaterial threads with complex transverse geometry are thus fragmented into a periodic train of rods held stationary in the polymer cladding. These rods can then be easily extracted via selective dissolution of the cladding, or can self-heal by thermal restoration to re-form the brittle thread. Our method is also applicable to composites with flat rather than cylindrical geometries, in which case cold-drawing leads to the break-up of an embedded or coated brittle film into narrow parallel strips that are aligned normally to the drawing axis. A range of materials was explored to establish the universality of this effect, including silicon, germanium, gold, glasses, silk, polystyrene, biodegradable polymers and ice. We observe, and verify through nonlinear finite-element simulations, a linear relationship between the smallest transverse scale and the longitudinal break-up period. These results may lead to the development of dynamical and thermoreversible camouflaging via a nanoscale Venetian-blind effect, and the fabrication of large-area structured surfaces that facilitate high-sensitivity bio-detection.

3.
Int J Neuropsychopharmacol ; 22(5): 329-338, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30927011

RESUMEN

BACKGROUND: Abnormalities in the hypothalamic-pituitary-adrenal axis, serotonergic system, and stress response have been linked to the pathogenesis of major depressive disorder. State-dependent hyper-reactivity of the hypothalamic-pituitary-adrenal axis is seen in major depressive disorder, and higher binding to the serotonin 1A receptor is observed as a trait in both currently depressed and remitted untreated major depressive disorder. Here, we sought to examine whether a relationship exists between cortisol secretion in response to a stressor and serotonin 1A receptor binding throughout the brain, both in healthy controls and participants with major depressive disorder. METHODS: Research participants included 42 medication-free, depressed subjects and 31 healthy volunteers. Participants were exposed to either an acute, physical stressor (radial artery catheter insertion) or a psychological stressor (Trier Social Stress Test). Levels of serotonin 1A receptor binding on positron emission tomography with [11C]WAY-100635 were also obtained from all participants. The relationship between [11C]WAY-100635 binding and cortisol was examined using mixed linear effects models with group (major depressive disorder vs control), cortisol, brain region, and their interactions as fixed effects and subject as a random effect. RESULTS: We found a positive correlation between post-stress cortisol measures and serotonin 1A receptor ligand binding levels across multiple cortical and subcortical regions, independent of diagnosis and with both types of stress. The relationship between [11C]WAY-100635 binding and cortisol was homogenous across all a priori brain regions. In contrast, resting cortisol levels were negatively correlated with serotonin 1A receptor ligand binding levels independently of diagnosis, except in the RN. There was no significant difference in cortisol between major depressive disorder participants and healthy volunteers with either stressor. Similarly, there was no correlation between cortisol and depression severity in either stressor group. CONCLUSIONS: This study suggests that there may be a common underlying mechanism that links abnormalities in the serotonin system and hypothalamic-pituitary-adrenal axis hyper-reactivity to stress. Future studies need to determine how hypothalamic-pituitary-adrenal axis dysfunction affects mood to increase the risk of suicide in major depression.


Asunto(s)
Encéfalo/metabolismo , Trastorno Depresivo Mayor/metabolismo , Hidrocortisona/metabolismo , Receptor de Serotonina 5-HT1A/metabolismo , Estrés Fisiológico/fisiología , Estrés Psicológico/metabolismo , Adolescente , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Radioisótopos de Carbono , Cateterismo , Trastorno Depresivo Mayor/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor Asociado a Procedimientos Médicos/diagnóstico por imagen , Dolor Asociado a Procedimientos Médicos/metabolismo , Piperazinas , Tomografía de Emisión de Positrones , Piridinas , Radiofármacos , Descanso , Estrés Psicológico/diagnóstico por imagen , Adulto Joven
4.
Bioorg Med Chem Lett ; 29(3): 367-372, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30587451

RESUMEN

Potent estrogen receptor ligands typically contain a phenolic hydrogen-bond donor. The indazole of the selective estrogen receptor degrader (SERD) ARN-810 is believed to mimic this. Disclosed herein is the discovery of ARN-810 analogs which lack this hydrogen-bond donor. These SERDs induced tumor regression in a tamoxifen-resistant breast cancer xenograft, demonstrating that the indazole NH is not necessary for robust ER-modulation and anti-tumor activity.


Asunto(s)
Antineoplásicos/farmacología , Cinamatos/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Indazoles/farmacología , Receptores de Estrógenos/antagonistas & inhibidores , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Tamoxifeno/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cinamatos/síntesis química , Cinamatos/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Indazoles/síntesis química , Indazoles/química , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/metabolismo , Neoplasias Mamarias Experimentales/patología , Ratones , Estructura Molecular , Receptores de Estrógenos/metabolismo , Moduladores Selectivos de los Receptores de Estrógeno/síntesis química , Moduladores Selectivos de los Receptores de Estrógeno/química , Relación Estructura-Actividad , Tamoxifeno/síntesis química , Tamoxifeno/química
5.
Proc Natl Acad Sci U S A ; 113(25): 6839-44, 2016 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-27274070

RESUMEN

Scattering of light from dielectric particles whose size is on the order of an optical wavelength underlies a plethora of visual phenomena in nature and is a foundation for optical coatings and paints. Tailoring the internal nanoscale geometry of such "photonic particles" allows tuning their optical scattering characteristics beyond those afforded by their constitutive materials-however, flexible yet scalable processing approaches to produce such particles are lacking. Here, we show that a thermally induced in-fiber fluid instability permits the "digital design" of multimaterial photonic particles: the precise allocation of high refractive-index contrast materials at independently addressable radial and azimuthal coordinates within its 3D architecture. Exploiting this unique capability in all-dielectric systems, we tune the scattering cross-section of equisized particles via radial structuring and induce polarization-sensitive scattering from spherical particles with broken internal rotational symmetry. The scalability of this fabrication strategy promises a generation of optical coatings in which sophisticated functionality is realized at the level of the individual particles.

6.
J Biol Chem ; 292(40): 16760-16772, 2017 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-28842495

RESUMEN

Hepatitis B virus (HBV) infection afflicts millions worldwide, causing cirrhosis and liver cancer. HBV e-antigen (HBeAg), a clinical marker for disease severity, is a soluble variant of the viral capsid protein. HBeAg is not required for viral replication but is implicated in establishing immune tolerance and chronic infection. The structure of recombinant e-antigen (rHBeAg) was recently determined, yet to date, the exact nature and quantitation of HBeAg still remain uncertain. Here, to further characterize HBeAg, we used phage display to produce a panel of chimeric rabbit/human monoclonal antibody fragments (both Fab and scFv) against rHBeAg. Several of the Fab/scFv, expressed in Escherichia coli, had unprecedentedly high binding affinities (Kd ∼10-12 m) and high specificity. We used Fab/scFv in the context of an enzyme-linked immunosorbent assay (ELISA) for HBeAg quantification, which we compared with commercially available kits and verified with seroconversion panels, the WHO HBeAg standard, rHBeAg, and patient plasma samples. We found that the specificity and sensitivity are superior to those of existing commercial assays. To identify potential fine differences between rHBeAg and HBeAg, we used these Fabs in microscale immunoaffinity chromatography to purify HBeAg from individual patient plasmas. Western blotting and MS results indicated that rHBeAg and HBeAg are essentially structurally identical, although HBeAg from different patients exhibits minor carboxyl-terminal heterogeneity. We discuss several potential applications for the humanized Fab/scFv.


Asunto(s)
Anticuerpos contra la Hepatitis B/inmunología , Antígenos e de la Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Hepatitis B/inmunología , Proteínas Recombinantes de Fusión/inmunología , Anticuerpos de Cadena Única/inmunología , Animales , Ensayo de Inmunoadsorción Enzimática/métodos , Hepatitis B/sangre , Hepatitis B/tratamiento farmacológico , Anticuerpos contra la Hepatitis B/química , Anticuerpos contra la Hepatitis B/genética , Anticuerpos contra la Hepatitis B/uso terapéutico , Antígenos e de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/química , Virus de la Hepatitis B/química , Humanos , Conejos , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/uso terapéutico , Anticuerpos de Cadena Única/química , Anticuerpos de Cadena Única/genética , Anticuerpos de Cadena Única/uso terapéutico
7.
Nature ; 487(7408): 463-7, 2012 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-22810590

RESUMEN

From drug delivery to chemical and biological catalysis and cosmetics, the need for efficient fabrication pathways for particles over a wide range of sizes, from a variety of materials, and in many different structures has been well established. Here we harness the inherent scalability of fibre production and an in-fibre Plateau-Rayleigh capillary instability for the fabrication of uniformly sized, structured spherical particles spanning an exceptionally wide range of sizes: from 2 mm down to 20 nm. Thermal processing of a multimaterial fibre controllably induces the instability, resulting in a well-ordered, oriented emulsion in three dimensions. The fibre core and cladding correspond to the dispersed and continuous phases, respectively, and are both frozen in situ on cooling, after which the particles are released when needed. By arranging a variety of structures and materials in a macroscopic scaled-up model of the fibre, we produce composite, structured, spherical particles, such as core-shell particles, two-compartment 'Janus' particles, and multi-sectioned 'beach ball' particles. Moreover, producing fibres with a high density of cores allows for an unprecedented level of parallelization. In principle, 10(8) 50-nm cores may be embedded in metres-long, 1-mm-diameter fibre, which can be induced to break up simultaneously throughout its length, into uniformly sized, structured spheres.


Asunto(s)
Técnicas de Química Sintética/métodos , Microesferas , Nanoestructuras/química , Catálisis , Preparaciones de Acción Retardada , Emulsiones/química , Vidrio/química , Nanoestructuras/ultraestructura , Tamaño de la Partícula , Polímeros/química , Temperatura
8.
Biochemistry ; 56(14): 2061-2070, 2017 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-28349680

RESUMEN

Z-disc-associated, alternatively spliced, PDZ motif-containing protein (ZASP) is a principal component of the sarcomere. The three prevalent isoforms of ZASP in skeletal muscle are generated by alternative splicing of exons 9 and 10. The long isoforms, either having (ZASP-L) or lacking exon 10 (ZASP-LΔex10), include an N-terminal PDZ domain, an actin-binding region (ABR) with a conserved motif (ZM), and three C-terminal LIM domains. The short isoform (ZASP-S) lacks the LIM domains. Mutations, A147T and A165V, within the ZM of ZASP-LΔex10 cause myofibrillar myopathy, but the mechanism is unknown. We have prepared these proteins, their ABR, and the respective mutant variants in recombinant form, characterized them biophysically, and analyzed their actin-binding properties by surface plasmon resonance and electron microscopy. All the proteins were physically homogeneous and monomeric and had circular dichroic spectra consistent with partially folded conformations. Comparison of the NMR HSQC spectra of ZASP-S and the PDZ domain showed that the ABR is unstructured. ZASP-S and its mutant variants and ZASP-LΔex10 all bound to immobilized G-actin with high affinity (Kd ≈ 10-8 to 10-9 M). Constructs of the isolated actin-binding region missing exon 10 (ABRΔ10) bound with lower affinity (Kd ≈ 10-7 M), but those retaining exon 10 (ABR+10) did so only weakly (Kd ≈ 10-5 M). ZASP-S, and the ABRΔ10, also induced F-actin and array formation, even in conditions of low ionic strength and in the absence of KCl and Mg2+ ions. Interestingly, the ZM mutations A147T and A165V did not affect any of the results described above.


Asunto(s)
Actinas/química , Proteínas Adaptadoras Transductoras de Señales/química , Proteínas con Dominio LIM/química , Actinas/genética , Actinas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Empalme Alternativo , Sitios de Unión , Escherichia coli/genética , Escherichia coli/metabolismo , Exones , Expresión Génica , Humanos , Intrones , Proteínas con Dominio LIM/genética , Proteínas con Dominio LIM/metabolismo , Mutación , Concentración Osmolar , Unión Proteica , Dominios Proteicos , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sarcómeros/fisiología , Relación Estructura-Actividad
9.
Proc Natl Acad Sci U S A ; 110(39): 15549-54, 2013 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-24019468

RESUMEN

Polymeric micro- and nanoparticles are becoming a mainstay in biomedicine, medical diagnostics, and therapeutics, where they are used in implementing sensing mechanisms, as imaging contrast agents, and in drug delivery. Current approaches to the fabrication of such particles are typically finely tuned to specific monomer or polymer species, size ranges, and structures. We present a general scalable methodology for fabricating uniformly sized spherical polymeric particles from a wide range of polymers produced with complex internal architectures and continuously tunable diameters extending from the millimeter scale down to 50 nm. Controllable access to such a wide range of sizes enables broad applications in cancer treatment, immunology, and vaccines. Our approach harnesses thermally induced, predictable fluid instabilities in composite core/cladding polymer fibers drawn from a macroscopic scaled-up model called a "preform." Through a stack-and-draw process, we produce fibers containing a multiplicity of identical cylindrical cores made of the polymers of choice embedded in a polymer cladding. The instability leads to the breakup of the initially intact cores, independent of the polymer chemistry, into necklaces of spherical particles held in isolation within the cladding matrix along the entire fiber length. We demonstrate here surface functionalization of the extracted particles for biodetection through specific protein-protein interactions, volumetric encapsulation of a biomaterial in spherical polymeric shells, and the combination of both surface and volumetric functionalities in the same particle. These particles used in distinct modalities may be produced from the desired biocompatible polymer by changing only the geometry of the macroscopic preform from which the fiber is drawn.


Asunto(s)
Técnicas Biosensibles/métodos , Composición de Medicamentos/métodos , Nanofibras/química , Polímeros/química , Materiales Biocompatibles , Emulsiones , Colorantes Fluorescentes/metabolismo , Nanofibras/ultraestructura , Proteínas/metabolismo
10.
J Biol Chem ; 289(19): 13615-26, 2014 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-24668811

RESUMEN

The core of skeletal muscle Z-discs consists of actin filaments from adjacent sarcomeres that are cross-linked by α-actinin homodimers. Z-disc-associated, alternatively spliced, PDZ motif-containing protein (ZASP)/Cypher interacts with α-actinin, myotilin, and other Z-disc proteins via the PDZ domain. However, these interactions are not sufficient to maintain the Z-disc structure. We show that ZASP directly interacts with skeletal actin filaments. The actin-binding domain is between the modular PDZ and LIM domains. This ZASP region is alternatively spliced so that each isoform has unique actin-binding domains. All ZASP isoforms contain the exon 6-encoded ZASP-like motif that is mutated in zaspopathy, a myofibrillar myopathy (MFM), whereas the exon 8-11 junction-encoded peptide is exclusive to the postnatal long ZASP isoform (ZASP-LΔex10). MFM is characterized by disruption of skeletal muscle Z-discs and accumulation of myofibrillar degradation products. Wild-type and mutant ZASP interact with α-actin, α-actinin, and myotilin. Expression of mutant, but not wild-type, ZASP leads to Z-disc disruption and F-actin accumulation in mouse skeletal muscle, as in MFM. Mutations in the actin-binding domain of ZASP-LΔex10, but not other isoforms, cause disruption of the actin cytoskeleton in muscle cells. These isoform-specific mutation effects highlight the essential role of the ZASP-LΔex10 isoform in F-actin organization. Our results show that MFM-associated ZASP mutations in the actin-binding domain have deleterious effects on the core structure of the Z-discs in skeletal muscle.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas con Dominio LIM/metabolismo , Mutación Missense , Miofibrillas/metabolismo , Citoesqueleto de Actina/genética , Citoesqueleto de Actina/patología , Actinina/genética , Actinina/metabolismo , Actinas/genética , Actinas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Secuencias de Aminoácidos , Animales , Línea Celular , Conectina/genética , Conectina/metabolismo , Humanos , Proteínas con Dominio LIM/genética , Ratones , Proteínas de Microfilamentos , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Miofibrillas/genética , Miopatías Estructurales Congénitas/genética , Miopatías Estructurales Congénitas/metabolismo , Miopatías Estructurales Congénitas/patología , Estructura Terciaria de Proteína
11.
Bioorg Med Chem Lett ; 25(22): 5163-7, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26463130

RESUMEN

Selective estrogen receptor degraders (SERDs) have shown promise for the treatment of ER+ breast cancer. Disclosed herein is the continued optimization of our indazole series of SERDs. Exploration of ER degradation and antagonism in vitro followed by in vivo antagonism and oral exposure culminated in the discovery of indazoles 47 and 56, which induce tumor regression in a tamoxifen-resistant breast cancer xenograft.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Antagonistas del Receptor de Estrógeno/uso terapéutico , Indazoles/uso terapéutico , Tamoxifeno/uso terapéutico , Animales , Antineoplásicos/química , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Cinamatos/uso terapéutico , Resistencia a Antineoplásicos , Antagonistas del Receptor de Estrógeno/metabolismo , Femenino , Indazoles/química , Ratas , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Antimicrob Agents Chemother ; 58(7): 3679-88, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24752271

RESUMEN

In the present study, GRL008, a novel nonpeptidic human immunodeficiency virus type 1 (HIV-1) protease inhibitor (PI), and darunavir (DRV), both of which contain a P2-bis-tetrahydrofuranyl urethane (bis-THF) moiety, were found to exert potent antiviral activity (50% effective concentrations [EC50s], 0.029 and 0.002 µM, respectively) against a multidrug-resistant clinical isolate of HIV-1 (HIVA02) compared to ritonavir (RTV; EC50, >1.0 µM) and tipranavir (TPV; EC50, 0.364 µM). Additionally, GRL008 showed potent antiviral activity against an HIV-1 variant selected in the presence of DRV over 20 passages (HIVDRV(R)P20), with a 2.6-fold increase in its EC50 (0.097 µM) compared to its corresponding EC50 (0.038 µM) against wild-type HIV-1NL4-3 (HIVWT). Based on X-ray crystallographic analysis, both GRL008 and DRV showed strong hydrogen bonds (H-bonds) with the backbone-amide nitrogen/carbonyl oxygen atoms of conserved active-site amino acids G27, D29, D30, and D30' of HIVA02 protease (PRA02) and wild-type PR in their corresponding crystal structures, while TPV lacked H-bonds with G27 and D30' due to an absence of polar groups. The P2' thiazolyl moiety of RTV showed two conformations in the crystal structure of the PRA02-RTV complex, one of which showed loss of contacts in the S2' binding pocket of PRA02, supporting RTV's compromised antiviral activity (EC50, >1 µM). Thus, the conserved H-bonding network of P2-bis-THF-containing GRL008 with the backbone of G27, D29, D30, and D30' most likely contributes to its persistently greater antiviral activity against HIVWT, HIVA02, and HIVDRV(R)P20.


Asunto(s)
Carbamatos/farmacología , Dominio Catalítico/efectos de los fármacos , Farmacorresistencia Viral Múltiple/efectos de los fármacos , Furanos/farmacología , Inhibidores de la Proteasa del VIH/farmacología , VIH-1/efectos de los fármacos , VIH-1/enzimología , Sulfonamidas/farmacología , Cristalización , Darunavir , Proteasa del VIH , Humanos , Enlace de Hidrógeno , Conformación Molecular , Datos de Secuencia Molecular , Pliegue de Proteína , Piridinas/farmacología , Pironas/farmacología , Difracción de Rayos X
13.
Soc Work Public Health ; 39(5): 405-421, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38722275

RESUMEN

This school program evaluation aims to highlight the mental health needs of students in special education with behavioral and emotional challenges and describe the implementation of a resilience curriculum with this population. We evaluated district mental health data from a convenience sample of 814 students in grades 5-12 special education to identify risk for mental health symptoms, violence exposure, and substance use. School social workers provided feedback on the implementation of the resilience curriculum to inform program evaluation. Students reported significant risk for traumatic stress, anxiety, and depressive symptoms, and high rates of violence exposure and substance use. School social workers described adaptations to the resilience curriculum and gave recommendations for future implementation. Students receiving special education services for behavioral and emotional challenges had high mental health need, including high rates of violence exposure, and may benefit from a trauma-informed school-based resilience curriculum adapted for their needs.


Asunto(s)
Curriculum , Educación Especial , Resiliencia Psicológica , Humanos , Masculino , Femenino , Adolescente , Niño , Estudiantes/psicología , Evaluación de Programas y Proyectos de Salud
14.
Antimicrob Agents Chemother ; 57(10): 4920-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23877703

RESUMEN

GRL007 and GRL008, two structurally related nonpeptidic human immunodeficiency virus type 1 (HIV-1) protease inhibitors (PIs) containing 3(R),3a(S),6a(R)-bis-tetrahydrofuranylurethane (bis-THF) as the P2 moiety and a sulfonamide isostere consisting of benzene carboxylic acid and benzene carboxamide as the P2' moiety, respectively, were evaluated for their antiviral activity and interactions with wild-type protease (PR(WT)). Both GRL007 (Ki of 12.7 pM with PR(WT)) and GRL008 (Ki of 8.9 pM) inhibited PR(WT) with high potency in vitro. X-ray crystallographic analysis of PR(WT) in complex with GRL007 or GRL008 showed that the bis-THF moiety of both compounds has three direct polar contacts with the backbone amide nitrogen atoms of Asp29 and Asp30 of PR(WT). The P2' moiety of both compounds showed one direct contact with the backbone of Asp30' and a bridging polar contact with Gly48' through a water molecule. Cell-based antiviral assays showed that GRL007 was inactive (50% effective concentration [EC50] of >1 µM) while GRL008 was highly active (EC50 of 0.04 µM) against wild-type HIV-1. High-performance liquid chromatography (HPLC)/mass spectrometry-based cellular uptake assays showed 8.1- and 84-fold higher intracellular concentrations of GRL008 than GRL007 in human MT-2 and MT-4 cell extracts, respectively. Thus, GRL007, in spite of its favorable enzyme-inhibitory activity and protease binding profile, exhibited a lack of antiviral activity in cell-based assays, most likely due to its compromised cellular uptake associated with its P2' benzene carboxylic acid moiety. The anti-HIV-1 potency, favorable toxicity, and binding profile of GRL008 suggest that further optimization of the P2' moiety may improve its antiretroviral features.


Asunto(s)
Benceno/química , Benzoatos/química , Inhibidores de la Proteasa del VIH/química , Inhibidores de la Proteasa del VIH/farmacología , Proteasa del VIH/química , Indoles/química , Dominio Catalítico , Línea Celular , Cromatografía Líquida de Alta Presión , Humanos , Espectrometría de Masa por Ionización de Electrospray , Relación Estructura-Actividad , Difracción de Rayos X
15.
Opt Lett ; 37(13): 2751-3, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22743517

RESUMEN

The development of robust infrared fibers is crucial for harnessing the capabilities of new mid-infrared lasers. We present a novel approach to the fabrication of chalcogenide glass fiber preforms: one-step multimaterial extrusion. The preform consists of a glass core and cladding surrounded by a built-in, thermally compatible, polymer jacket for mechanical support. Using this approach we extrude several preform structures and draw them into robust composite fibers. Furthermore, the polymer cladding allows us to produce robust tapers with submicrometer core diameter.

16.
Nano Lett ; 11(11): 4768-73, 2011 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-21967545

RESUMEN

We investigate the lower limit of nanowire diameters stably produced by the process of thermal fiber drawing and fiber tapering. A centimeter-scale macroscopic cylindrical preform containing the nanowire material in the core encased in a polymer scaffold cladding is thermally drawn in the viscous state to a fiber. By cascading several iterations of the process, continuous reduction of the diameter of an amorphous semiconducting chalcogenide glass is demonstrated. Starting from a 10-mm-diameter rod we thermally draw hundreds of meters of continuous sub-5-nm-diameter nanowires. Using this approach, we produce macroscopic lengths of high-density, well-ordered, globally oriented nanowire arrays.


Asunto(s)
Nanotubos/química , Nanotubos/ultraestructura , Calor , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie
17.
J Biol Chem ; 285(4): 2438-55, 2010 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-19940160

RESUMEN

Mediator is a multisubunit coactivator required for initiation by RNA polymerase II. The Mediator tail subdomain, containing Med15/Gal11, is a target of the activator Gcn4 in vivo, critical for recruitment of native Mediator or the Mediator tail subdomain present in sin4Delta cells. Although several Gal11 segments were previously shown to bind Gcn4 in vitro, the importance of these interactions for recruitment of Mediator and transcriptional activation by Gcn4 in cells was unknown. We show that interaction of Gcn4 with the Mediator tail in vitro and recruitment of this subcomplex and intact Mediator to the ARG1 promoter in vivo involve additive contributions from three different segments in the N terminus of Gal11. These include the KIX domain, which is a critical target of other activators, and a region that shares a conserved motif (B-box) with mammalian coactivator SRC-1, and we establish that B-box is a critical determinant of Mediator recruitment by Gcn4. We further demonstrate that Gcn4 binds to the Gal11 KIX domain directly and, by NMR chemical shift analysis combined with mutational studies, we identify the likely binding site for Gcn4 on the KIX surface. Gcn4 is distinctive in relying on comparable contributions from multiple segments of Gal11 for efficient recruitment of Mediator in vivo.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico , Regulación Fúngica de la Expresión Génica , Complejo Mediador , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Secuencia de Aminoácidos , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/química , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Secuencia Conservada , Complejo Mediador/química , Complejo Mediador/genética , Complejo Mediador/metabolismo , Resonancia Magnética Nuclear Biomolecular , Fenotipo , Dominios y Motivos de Interacción de Proteínas/fisiología , Estructura Terciaria de Proteína , Subunidades de Proteína/química , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , ARN Polimerasa II/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transcripción Genética/fisiología
18.
J Dent Educ ; 85(10): 1664-1673, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34117646

RESUMEN

Substance Use Disorders (SUD) are chronic health conditions with heritability characteristics, environmental influences, long-term management considerations and they cooccur. The US opioid epidemic is a crisis of both prescription and nonprescription opioid use. Clinicians now have access to evidence-based practices but the evolving trends require continuous attention including curriculum initiatives for dental schools. The purpose of this study was to obtain information about the content and educational strategies of current SUD curricula, beneficial educational products for a standardized curriculum and perceived barriers toward standardization. Invitations were sent to 64 US dental schools describing the purpose of this study and a link to complete the survey was provided. Fully completed responses were received from 32 (50.0%) of the schools. Descriptive statistics was used to analyze the data. Most dental schools surveyed (81.3%) have a curriculum for SUD with classroom lectures being the most commonly used teaching method (96.2%), followed by online modules (42.3%). About 30% of the responding schools provided additional educational experiences. Instruction occurred mostly in second (73.1%) and third (77.0%) academic years. Opioids, alcohol, nicotine, and marijuana were the most frequently taught substance classes. Curriculum standardization with online modules (81.3%), case-based exercises (59.4%), and simulation with standardized patients (43.8%) was considered desirable to improve student competency in the management of patients with SUD. Lack of time (62.5%), space (56.3%), and faculty (50.0%) were cited as the most common barriers to curriculum initiatives. Experiential and achievable options for improving SUD curriculum were highlighted.


Asunto(s)
Facultades de Odontología , Trastornos Relacionados con Sustancias , Curriculum , Educación en Odontología , Humanos , Encuestas y Cuestionarios , Estados Unidos
19.
Biochem J ; 419(2): 497-506, 2009 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-19149765

RESUMEN

Active-site inhibitors of HIV-1 PR (protease) block viral replication by preventing viral maturation. However, HIV-1 often develops resistance to active-site inhibitors through multiple mutations in PR and therefore recent efforts have focused on inhibiting PR dimerization as an alternative approach. Dimerization inhibitors have been identified using kinetic analysis, but additional characterization of the effect of these inhibitors on PR by physical methods has been difficult. In the present study, we identified a PR(MDR) (multi-drug-resistant HIV-1 PR) that was highly resistant to autoproteolysis. Using this PR and a novel size-exclusion chromatographic approach that incorporated fluorescence and MS detection, we were able to demonstrate inhibition of dimerization using P27 (peptide 27), a peptide dimerization inhibitor of PR previously identified on the basis of kinetic analysis. Incubation of PR(MDR) with P27, or other dimerization inhibitors, led to a dose- and time-dependent formation of PR monomers based on the change in elution time by size exclusion and its similar elution time to engineered forms of monomeric PR, namely PR(T26A) and glutathionylated PR. In contrast, incubation of PR(MDR) with a potent active-site inhibitor did not change the elution time for the PR(MDR) dimer. The monomeric PR induced by P27 had fluorescent characteristics which were consistent with unfolded PR. Structure-activity studies identified the active regions of P27 and experiments were performed to examine the effect of other dimerization inhibitors on PR. The present study is the first characterization of dimerization inhibition of PR(MDR), a prime target for these inhibitors, using a novel size-exclusion chromatographic approach.


Asunto(s)
Cromatografía en Gel/métodos , Proteasa del VIH/química , Proteasa del VIH/metabolismo , Multimerización de Proteína/efectos de los fármacos , Espectrometría de Masas , Péptidos/química , Péptidos/farmacología , Estabilidad Proteica/efectos de los fármacos , Relación Estructura-Actividad
20.
Dent Clin North Am ; 64(3): 535-546, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32448457

RESUMEN

Dental patients who experience comorbid psychiatric and medical conditions present an elevated risk of medication misuse, abuse, substance use disorders, and overdose. The authors review the role of notable comorbidities in predicting the development of substance use disorder, including medical, psychiatric, and other psychosocial factors that can be assessed in general dental practice. Psychiatric disorders commonly cooccur with substance abuse, and these typically include anxiety disorders, mood disorders (major depression, bipolar), posttraumatic stress, as well as sleep and eating disorders. Medical disorders commonly found to be present with substance use disorders are also reviewed, including common cardiovascular and pulmonary disorders.


Asunto(s)
Sustancias Controladas , Trastornos Relacionados con Sustancias/epidemiología , Trastornos de Ansiedad/epidemiología , Comorbilidad , Humanos
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