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1.
PLOS Glob Public Health ; 3(7): e0001381, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37410723

RESUMEN

We conducted an independent evaluation on the effectiveness of an organisational-level monetary incentive to encourage small and medium-sized enterprises (SMEs) to improve employees' health and wellbeing. This was A mixed-methods cluster randomised trial with four arms: high monetary incentive, low monetary incentive, and two no monetary incentive controls (with or without baseline measurements to examine 'reactivity' The consequence of particpant awareness of being studied, and potential impact on participant behavior effects). SMEs with 10-250 staff based in West Midlands, England were eligible. We randomly selected up to 15 employees at baseline and 11 months post-intervention. We elicited employee perceptions of employers' actions to improve health and wellbeing; and employees' self-reported health behaviours and wellbeing. We also interviewed employers and obtained qualitative data. One hundred and fifty-two SMEs were recruited. Baseline assessments were conducted in 85 SMEs in three arms, and endline assessments in 100 SMEs across all four arms. The percentage of employees perceiving "positive action" by their employer increased after intervention (5 percentage points, pp [95% Credible Interval -3, 21] and 3pp [-9, 17], in models for high and low incentive groups). Across six secondary questions about specific issues the results were strongly and consistently positive, especially for the high incentive. This was consistent with qualitative data and quantitative employer interviews. However, there was no evidence of any impact on employee health behaviour or wellbeing outcomes, nor evidence of 'reactivity'. An organisational intervention (a monetary incentive) changed employee perceptions of employer behaviour but did not translate into changes in employees' self-reports of their own health behaviours or wellbeing. Trial registration: AEARCTR-0003420, registration date: 17.10.2018, retrospectively registered (delays in contracts and identfying a suitable trial registry). The authors confirm that there are no ongoing and related trials for this intervention.

2.
Nat Chem Biol ; 19(3): 323-333, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36329119

RESUMEN

Targeted protein degradation is a novel pharmacology established by drugs that recruit target proteins to E3 ubiquitin ligases. Based on the structure of the degrader and the target, different E3 interfaces are critically involved, thus forming defined 'functional hotspots'. Understanding disruptive mutations in functional hotspots informs on the architecture of the assembly, and highlights residues susceptible to acquire resistance phenotypes. Here we employ haploid genetics to show that hotspot mutations cluster in substrate receptors of hijacked ligases, where mutation type and frequency correlate with gene essentiality. Intersection with deep mutational scanning revealed hotspots that are conserved or specific for chemically distinct degraders and targets. Biophysical and structural validation suggests that hotspot mutations frequently converge on altered ternary complex assembly. Moreover, we validated hotspots mutated in patients that relapse from degrader treatment. In sum, we present a fast and widely accessible methodology to characterize small-molecule degraders and associated resistance mechanisms.


Asunto(s)
Proteínas Portadoras , Ubiquitina-Proteína Ligasas , Ubiquitina-Proteína Ligasas/metabolismo , Proteolisis , Proteínas Portadoras/metabolismo
3.
Br J Nurs ; 30(13): S19-S24, 2021 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-34251853

RESUMEN

COVID-19 and rising student numbers are affecting healthcare education, particularly access to clinical placements. As healthcare education is increasingly supported by technology and non-traditional teaching methods, educational experiences gained through clinical placement also require new approaches. This article explores and discusses the use of a simulated clinical placement for a dietetic student cohort. During this virtual placement, students were able to explore and experience a virtual clinical setting and immerse themselves in a placement experience. A vast range of virtual resources were linked to the online placement portal, including statutory and mandatory training, dietetic resources, patient journeys and interprofessional communication. Advantages of this approach include that all students experience a given situation, unlike in traditional placements where workloads, variety and engagement vary; there is also no risk to patient safety. The aim is to enhance the learning experience to create effective, efficient clinicians. This virtual placement for dietetics is part of a bigger project to develop and evaluate the use of a virtual placement framework in a range of professions. The concept of virtual placement may have been brought forward by the COVID-19 crisis but was inevitable with the move to more technology-enhanced learning tools.


Asunto(s)
Educación a Distancia , Bachillerato en Enfermería , Entrenamiento Simulado , Estudiantes de Enfermería , COVID-19/epidemiología , Educación a Distancia/organización & administración , Bachillerato en Enfermería/organización & administración , Humanos , Aprendizaje , Investigación en Educación de Enfermería , Investigación en Evaluación de Enfermería , Proyectos Piloto , Entrenamiento Simulado/organización & administración , Estudiantes de Enfermería/psicología , Reino Unido/epidemiología
4.
Parasit Vectors ; 13(1): 87, 2020 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-32070403

RESUMEN

BACKGROUND: Anopheles funestus (s.s.) is a primary vector of the malaria parasite Plasmodium falciparum in Africa, a human pathogen that causes almost half a million deaths each year. The population structure of An. funestus was examined in samples from Uganda and the southern African countries of Malawi, Mozambique, Zambia and Zimbabwe. METHODS: Twelve microsatellites were used to estimate the genetic diversity and differentiation of An. funestus from 13 representative locations across five countries. These were comprised of four sites from Uganda, three from Malawi and two each from Mozambique, Zambia and Zimbabwe. RESULTS: All loci were highly polymorphic across the populations with high allelic richness and heterozygosity. A high genetic diversity was observed with 2-19 alleles per locus and an average number of seven alleles. Overall, expected heterozygosity (He) ranged from 0.65 to 0.79. When samples were pooled three of the 12 microsatellite loci showed Hardy-Weinberg equilibrium. Unsupervised Bayesian clustering analysis of microsatellite data revealed two clusters with An. funestus samples from Mozambique, Uganda and Zambia falling into one group and Malawi and Zimbabwe into another. The overall genetic differentiation between the populations was moderate (FST = 0.116). Pairwise differentiation between the pairs was low but significant. A weak but significant correlation was established between genetic and geographical distance for most populations. CONCLUSIONS: High genetic diversity revealed by the loci with low to moderate differentiation, identified two clusters among the An. funestus populations. Further research on the population dynamics of An. funestus in east and southern Africa is essential to understand the implications of this structuring and what effect it may have on the efficient implementation of mosquito vector control strategies.


Asunto(s)
Anopheles/genética , Variación Genética , Genética de Población , África Austral , Animales , Teorema de Bayes , ADN Mitocondrial , Geografía , Repeticiones de Microsatélite , Mosquitos Vectores/genética , Uganda
5.
Angew Chem Int Ed Engl ; 59(4): 1727-1734, 2020 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-31746102

RESUMEN

Constraining a molecule in its bioactive conformation via macrocyclization represents an attractive strategy to rationally design functional chemical probes. While this approach has been applied to enzyme inhibitors or receptor antagonists, to date it remains unprecedented for bifunctional molecules that bring proteins together, such as PROTAC degraders. Herein, we report the design and synthesis of a macrocyclic PROTAC by adding a cyclizing linker to the BET degrader MZ1. A co-crystal structure of macroPROTAC-1 bound in a ternary complex with VHL and the second bromodomain of Brd4 validated the rational design. Biophysical studies revealed enhanced discrimination between the second and the first bromodomains of BET proteins. Despite a 12-fold loss of binary binding affinity for Brd4, macroPROTAC-1 exhibited cellular activity comparable to MZ1. Our findings support macrocyclization as an advantageous strategy to enhance PROTAC degradation potency and selectivity between homologous targets.


Asunto(s)
Diseño de Fármacos , Compuestos Macrocíclicos , Compuestos Macrocíclicos/química , Estructura Molecular , Conformación Proteica
6.
PLoS One ; 14(5): e0216417, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31083672

RESUMEN

Dopamine (DA) is a neurotransmitter with actions across phylogeny that modulate core behaviors such as motor activity, reward, attention, and cognition. Perturbed DA signaling in humans is associated with multiple disorders, including addiction, ADHD, schizophrenia, and Parkinson's disease. The presynaptic DA transporter exerts powerful control on DA signaling by efficient clearance of the neurotransmitter following release. As in vertebrates, Caenorhabditis elegans DAT (DAT-1) constrains DA signaling and loss of function mutations in the dat-1 gene result in slowed crawling on solid media and swimming-induced paralysis (Swip) in water. Previously, we identified a mutant line, vt34, that exhibits robust DA-dependent Swip. vt34 exhibits biochemical and behavioral phenotypes consistent with reduced DAT-1 function though vt34; dat-1 double mutants exhibit an enhanced Swip phenotype, suggesting contributions of the vt34-associated mutation to additional mechanisms that lead to excess DA signaling. SNP mapping and whole genome sequencing of vt34 identified the site of the molecular lesion in the gene B0412.2 that encodes the Runx transcription factor ortholog RNT-1. Unlike dat-1 animals, but similar to other loss of function rnt-1 mutants, vt34 exhibits altered male tail morphology and reduced body size. Deletion mutations in both rnt-1 and the bro-1 gene, which encodes a RNT-1 binding partner also exhibit Swip. Both vt34 and rnt-1 mutations exhibit reduced levels of dat-1 mRNA as well as the tyrosine hydroxylase ortholog cat-2. Although reporter studies indicate that rnt-1 is expressed in DA neurons, its re-expression in DA neurons of vt34 animals fails to fully rescue Swip. Moreover, as shown for vt34, rnt-1 mutation exhibits additivity with dat-1 in generating Swip, as do rnt-1 and bro-1 mutations, and vt34 exhibits altered capacity for acetylcholine signaling at the neuromuscular junction. Together, these findings identify a novel role for rnt-1 in limiting DA neurotransmission and suggest that loss of RNT-1 may disrupt function of both DA neurons and body wall muscle to drive Swip.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Dopamina/metabolismo , Mutación con Pérdida de Función , Parálisis , Natación , Factores de Transcripción , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Dopamina/genética , Neuronas Dopaminérgicas/metabolismo , Parálisis/genética , Parálisis/metabolismo , Transducción de Señal/genética , Factores de Transcripción/metabolismo
8.
J Infect Prev ; 20(1): 37-45, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30719087

RESUMEN

BACKGROUND: Little evidence exists to show the exact impact of the link nurse role in promoting best practice in infection prevention. This paper is a report of the implementation and evaluation of a link nurse programme for community hospitals across one NHS organisation. AIM/OBJECTIVES: The main aim of the study was to implement and evaluate an infection prevention link programme. The study objectives were: 1) to develop materials for a bespoke infection prevention programme which incorporated education, behaviour change, reward and recognition and 2) to evaluate the implementation of the programme, and to learn about barriers and enablers to implementation. METHOD: Data were collected using semi-structured telephone interviews, contact logs and online course evaluation. Data were analysed using thematic analysis. FINDINGS: We identified four overarching themes that, collectively, construct a model for the implementation of the link nurse role in infection prevention. The themes are labelled as: selection process, support networks, essential roots, and turning points for success. DISCUSSION: This study contributes to understanding the contribution of link nurses in infection prevention. We suggest our findings are transferable to different settings, and the model provides guidance to support future link nurse programmes and promote best practice in infection prevention practice.

9.
Contemp Nurse ; 54(4-5): 472-482, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30295135

RESUMEN

BACKGROUND: The widespread use of telehealth brings benefits to improve access to healthcare for rural and remote populations. OBJECTIVE: This study explores what nurses considered important to confidently and competently participate in telehealth. DESIGN: A descriptive qualitative approach was selected. METHODS: Nine New Zealand Registered Nurses who worked in different clinical settings who use telehealth were identified through snowball sampling, and participated in single semi-structured interviews, which were thematically analysed using a general inductive approach. FINDINGS: The nurses' experience of using telehealth, from novice to becoming more proficient, was the main theme identified, with sub-themes of: Initial use of telehealth, hands-on training, specialty experience, mentorship and technological know-how. The confidence of nurses using telehealth in this study may reflect their clinical nursing experience. CONCLUSION: Recommendations include the need for more telehealth education and preparation, including incorporating telehealth in under and postgraduate nursing programmes. Additionally, specific telehealth nursing competencies are warranted.


Asunto(s)
Competencia Clínica/estadística & datos numéricos , Competencia Clínica/normas , Atención a la Salud/métodos , Personal de Enfermería/psicología , Personal de Enfermería/normas , Telemedicina/normas , Adulto , Femenino , Humanos , Masculino , Nueva Zelanda , Investigación Cualitativa , Encuestas y Cuestionarios , Adulto Joven
10.
J Am Chem Soc ; 140(29): 9299-9313, 2018 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-29949369

RESUMEN

Hydroxylation and fluorination of proline alters the pyrrolidine ring pucker and the trans:cis amide bond ratio in a stereochemistry-dependent fashion, affecting molecular recognition of proline-containing molecules by biological systems. While hydroxyprolines and fluoroprolines are common motifs in medicinal and biological chemistry, the synthesis and molecular properties of prolines containing both modifications, i.e., fluoro-hydroxyprolines, have not been described. Here we present a practical and facile synthesis of all four diastereoisomers of 3-fluoro-4-hydroxyprolines (F-Hyps), starting from readily available 4-oxo-l-proline derivatives. Small-molecule X-ray crystallography, NMR spectroscopy, and quantum mechanical calculations are consistent with fluorination at C3 having negligible effects on the hydrogen bond donor capacity of the C4 hydroxyl, but inverting the natural preference of Hyp from C4-exo to C4-endo pucker. In spite of this, F-Hyps still bind to the von Hippel-Lindau (VHL) E3 ligase, which naturally recognizes C4-exo Hyp in a stereoselective fashion. Co-crystal structures and electrostatic potential calculations support and rationalize the observed preferential recognition for (3 R,4 S)-F-Hyp over the corresponding (3 S,4 S) epimer by VHL. We show that (3 R,4 S)-F-Hyp provides bioisosteric Hyp substitution in both hypoxia-inducible factor 1 alpha (HIF-1α) substrate peptides and peptidomimetic ligands that form part of PROTAC (proteolysis targeting chimera) conjugates for targeted protein degradation. Despite a weakened affinity, Hyp substitution with (3 S,4 S)-F-Hyp within the PROTAC MZ1 led to Brd4-selective cellular degradation at concentrations >100-fold lower than the binary Kd for VHL. We anticipate that the disclosed chemistry of 3-fluoro-4-hydroxyprolines and their application as VHL ligands for targeted protein degradation will be of wide interest to medicinal organic chemists, chemical biologists, and drug discoverers alike.


Asunto(s)
Prolina/análogos & derivados , Prolina/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Teoría Funcional de la Densidad , Enlace de Hidrógeno , Modelos Químicos , Conformación Molecular , Prolina/síntesis química , Unión Proteica , Estereoisomerismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/química
11.
Mol Omics ; 14(3): 142-155, 2018 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-29868674

RESUMEN

The C. elegans gene swip-10 encodes an orphan metallo ß-lactamase that genetic studies indicate is vital for limiting neuronal excitability and viability. Sequence analysis indicates that the mammalian gene Mblac1 is the likely ortholog of swip-10, with greatest sequence identity localized to the encoded protein's single metallo ß-lactamase domain. The substrate for the SWIP-10 protein remains unknown and to date no functional roles have been ascribed to MBLAC1, though we have shown that the protein binds the neuroprotective ß-lactam antibiotic, ceftriaxone. To gain insight into the functional role of MBLAC1 in vivo, we used CRISPR/Cas9 methods to disrupt N-terminal coding sequences of the mouse Mblac1 gene, resulting in a complete loss of protein expression in viable, homozygous knockout (KO) animals. Using serum from both WT and KO mice, we performed global, untargeted metabolomic analyses, resolving small molecules via hydrophilic interaction chromatography (HILIC) based ultra-performance liquid chromatography, coupled to mass spectrometry (UPLC-MS/MS). Unsupervised principal component analysis reliably segregated the metabolomes of MBLAC1 KO and WT mice, with 92 features subsequently nominated as significantly different by ANOVA, and for which we made tentative and putative metabolite assignments. Bioinformatic analyses of these molecules nominate validated pathways subserving bile acid biosynthesis and linoleate metabolism, networks known to be responsive to metabolic and oxidative stress. Our findings lead to hypotheses that can guide future targeted studies seeking to identify the substrate for MBLAC1 and how substrate hydrolysis supports the neuroprotective actions of ceftriaxone.

12.
Brain ; 140(11): 2838-2850, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29088354

RESUMEN

The presynaptic, high-affinity choline transporter is a critical determinant of signalling by the neurotransmitter acetylcholine at both central and peripheral cholinergic synapses, including the neuromuscular junction. Here we describe an autosomal recessive presynaptic congenital myasthenic syndrome presenting with a broad clinical phenotype due to homozygous choline transporter missense mutations. The clinical phenotype ranges from the classical presentation of a congenital myasthenic syndrome in one patient (p.Pro210Leu), to severe neurodevelopmental delay with brain atrophy (p.Ser94Arg) and extend the clinical outcomes to a more severe spectrum with infantile lethality (p.Val112Glu). Cells transfected with mutant transporter construct revealed a virtually complete loss of transport activity that was paralleled by a reduction in transporter cell surface expression. Consistent with these findings, studies to determine the impact of gene mutations on the trafficking of the Caenorhabditis elegans choline transporter orthologue revealed deficits in transporter export to axons and nerve terminals. These findings contrast with our previous findings in autosomal dominant distal hereditary motor neuropathy of a dominant-negative frameshift mutation at the C-terminus of choline transporter that was associated with significantly reduced, but not completely abrogated choline transporter function. Together our findings define divergent neuropathological outcomes arising from different classes of choline transporter mutation with distinct disease processes and modes of inheritance. These findings underscore the essential role played by the choline transporter in sustaining acetylcholine neurotransmission at both central and neuromuscular synapses, with important implications for treatment and drug selection.


Asunto(s)
Encéfalo/patología , Mutación Missense , Síndromes Miasténicos Congénitos/genética , Trastornos del Neurodesarrollo/genética , Simportadores/genética , Animales , Animales Modificados Genéticamente , Atrofia , Axones/metabolismo , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Preescolar , Femenino , Células HEK293 , Homocigoto , Humanos , Lactante , Masculino , Proteínas de Transporte de Membrana/genética , Linaje , Terminales Presinápticos/metabolismo , Transporte de Proteínas , Simportadores/metabolismo
13.
ACS Chem Neurosci ; 8(10): 2132-2138, 2017 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-28783953

RESUMEN

Ceftriaxone, a ß-lactam antibiotic, has been reported to act independently of its antimicrobial actions to normalize perturbed central nervous system glutamate levels, principally by elevating expression of glial glutamate transporters. Identification of a specific, high-affinity target for ceftriaxone could significantly impact therapeutic development for multiple brain disorders, ranging from neurodegenerative disorders to addiction. Recently, we identified a glial-expressed Caenorhabditis elegans gene, swip-10, that encodes a metallo-ß-lactamase domain-containing protein, and limits glutamate-dependent changes in dopamine neuron excitability. Bioinformatic analyses identified MBLAC1 as the likely mammalian orthologue of swip-10. Using cyanogen bromide immobilized ceftriaxone for affinity capture experiments and backscattering interferometry to monitor MBLAC1 binding of unmodified ceftriaxone, we obtained evidence for specific, high affinity (KD = 2.2 µM) binding of ceftriaxone to MBLAC1. We discuss our findings with respect to MBLAC1 as a potentially exclusive, high-affinity binding partner of ceftriaxone in the CNS, and the path forward in the development of novel, MBLAC1-based therapeutics.


Asunto(s)
Antibacterianos/metabolismo , Ceftriaxona/metabolismo , Hidrolasas/metabolismo , Sistema de Transporte de Aminoácidos X-AG/metabolismo , Animales , Antibacterianos/farmacología , Caenorhabditis elegans , Ceftriaxona/farmacología , Sistema Nervioso Central/efectos de los fármacos , Sistema Nervioso Central/metabolismo , Ratones
14.
Mol Cell Neurosci ; 78: 41-51, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27913309

RESUMEN

The monoamine neurotransmitter dopamine (DA) acts across phylogeny to modulate both simple and complex behaviors. The presynaptic DA transporter (DAT) is a major determinant of DA signaling capacity in ensuring efficient extracellular DA clearance. In humans, DAT is also a major target for prescribed and abused psychostimulants. Multiple structural determinants of DAT function and regulation have been defined, though largely these findings have arisen from heterologous expression or ex vivo cell culture studies. Loss of function mutations in the gene encoding the Caenhorhabditis elegans DAT (dat-1) produces rapid immobility when animals are placed in water, a phenotype termed swimming-induced paralysis (Swip). The ability of a DA neuron-expressed, GFP-tagged DAT-1 fusion protein (GFP::DAT-1) to localize to synapses and rescue Swip in these animals provides a facile approach to define sequences supporting DAT somatic export and function in vivo. In prior studies, we found that truncation of the last 25 amino acids of the DAT-1 C-terminus (Δ25) precludes Swip rescue, supported by a deficit in GFP::DAT-1 synaptic localization. Here, we further defined the elements within Δ25 required for DAT-1 export and function in vivo. We identified two conserved motifs (584KW585 and 591PYRKR595) where mutation results in a failure of GFP::DAT-1 to be efficiently exported to synapses and restore DAT-1 function. The 584KW585 motif conforms to a sequence proposed to support SEC24 binding, ER export from the endoplasmic reticulum (ER), and surface expression of mammalian DAT proteins, whereas the 591PYRKR595 sequence conforms to a 3R motif identified as a SEC24 binding site in vertebrate G-protein coupled receptors. Consistent with a potential role of SEC24 orthologs in DAT-1 export, we demonstrated DA neuron-specific expression of a sec-24.2 transcriptional reporter. Mutations of the orthologous C-terminal sequences in human DAT (hDAT) significantly reduced transporter surface expression and DA uptake, despite normal hDAT protein expression. Although, hDAT mutants retained SEC24 interactions, as defined in co-immunoprecipitation studies. However, these mutations disrupted the ability of SEC24D to enhance hDAT surface expression. Our studies document an essential role of conserved DAT C-terminal sequences in transporter somatic export and synaptic localization in vivo, that add further support for important roles for SEC24 family members in efficient transporter trafficking.


Asunto(s)
Transporte Axonal , Proteínas de Caenorhabditis elegans/metabolismo , Secuencia Conservada , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Señales de Clasificación de Proteína , Animales , Sitios de Unión , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/química , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Evolución Molecular , Proteínas Activadoras de GTPasa/genética , Proteínas Activadoras de GTPasa/metabolismo , Unión Proteica , Sinapsis/metabolismo
15.
Bioorg Med Chem Lett ; 26(19): 4637-4640, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27575469

RESUMEN

This Letter describes the further lead optimization of the CHT inhibitor probe, ML352 (VU0476201), and the development of VU6001221, an improved in vivo tool. A multi-dimensional optimization effort encountered steep SAR, and ultimately, subtle tuning of the electronics of the central phenyl core provided VU6001221, a CHT inhibitor with comparable potency for choline uptake inhibition as ML352, yet improved PK and CNS penetration. Moreover, VU6001221 enabled evaluation, for the first time, of a CHT inhibitor in a standard preclinical rodent cognition model, novel object recognition (NOR). We observed VU6001221 to elicit a dose-responsive increase in NOR, raising the possibility of agonism of synaptic α7 nicotinic ACh receptors by elevated extracellular choline, that if confirmed would represent a novel molecular strategy to enhance cognition.


Asunto(s)
Benzamidas/farmacología , Isoxazoles/farmacología , Proteínas de Transporte de Membrana/efectos de los fármacos , Oxazoles/farmacología , Piperidinas/farmacología , Animales , Benzamidas/química , Benzamidas/farmacocinética , Relación Dosis-Respuesta a Droga , Semivida , Concentración 50 Inhibidora , Isoxazoles/química , Isoxazoles/farmacocinética , Oxazoles/química , Oxazoles/farmacocinética , Piperidinas/química , Piperidinas/farmacocinética , Ratas , Relación Estructura-Actividad
16.
J Prosthet Dent ; 115(2): 209-14, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26460168

RESUMEN

STATEMENT OF PROBLEM: Agenesis of the maxillary lateral incisor has been linked to differences in the size of the remaining teeth. Thus, the mesiodistal space required for definitive esthetic restoration in patients with missing maxillary lateral incisors may be reduced. PURPOSE: The purpose of this study was to determine whether a tooth size discrepancy exists in orthodontic patients with agenesis of one or both maxillary lateral incisors. MATERIAL AND METHODS: Forty sets of dental casts from orthodontic patients (19 men and 21 women; mean 15.9 years of age; all of European origin) were collected. All casts had agenesis of one or both maxillary lateral incisors. Teeth were measured with a digital caliper at their greatest mesiodistal width and then compared with those of a control group matched for ethnicity, age, and sex. Four-factor ANOVA with repeated measures of 2 factors was used for statistical analysis (α=.05). RESULTS: Orthodontic patients with agenesis of one or both maxillary lateral incisors exhibited smaller than normal tooth size compared with the control group. The maxillary arch had a larger tooth size difference between the control and test groups than the mandibular arch (there was a significant Jaw × Group interaction [F=4.78, P=.032]). CONCLUSIONS: Agenesis of one or both maxillary lateral incisors is significantly associated with tooth size discrepancy, which may affect the space remaining for restoration of the remaining teeth.


Asunto(s)
Incisivo/anomalías , Incisivo/anatomía & histología , Corona del Diente/patología , Adolescente , Anodoncia/genética , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Maxilar , Odontometría
17.
Bioorg Med Chem Lett ; 25(8): 1757-1760, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25801932

RESUMEN

The synthesis and SAR of 4-methoxy-3-(piperidin-4-yl) benzamides identified after a high-throughput screen of the MLPCN library is reported. SAR was explored around the 3-piperidine substituent as well as the amide functionality of the reported compounds. Starting from the initial lead compounds, 1-7, iterative medicinal chemistry efforts led to the identification of ML352 (10m). ML352 represents a potent and selective inhibitor of CHT based on a drug-like scaffold.


Asunto(s)
Benzamidas/química , Proteínas de Transporte de Membrana/química , Animales , Benzamidas/síntesis química , Benzamidas/farmacocinética , Células HEK293 , Semivida , Humanos , Proteínas de Transporte de Membrana/metabolismo , Piperidinas/química , Unión Proteica , Ratas , Relación Estructura-Actividad , Simportadores/antagonistas & inhibidores , Simportadores/metabolismo , Distribución Tisular
18.
ACS Chem Neurosci ; 6(3): 417-27, 2015 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-25560927

RESUMEN

The high-affinity choline transporter (CHT) is the rate-limiting determinant of acetylcholine (ACh) synthesis, yet the transporter remains a largely undeveloped target for the detection and manipulation of synaptic cholinergic signaling. To expand CHT pharmacology, we pursued a high-throughput screen for novel CHT-targeted small molecules based on the electrogenic properties of transporter-mediated choline transport. In this effort, we identified five novel, structural classes of CHT-specific inhibitors. Chemical diversification and functional analysis of one of these classes identified ML352 as a high-affinity (Ki = 92 nM) and selective CHT inhibitor. At concentrations that fully antagonized CHT in transfected cells and nerve terminal preparations, ML352 exhibited no inhibition of acetylcholinesterase (AChE) or cholineacetyltransferase (ChAT) and also lacked activity at dopamine, serotonin, and norepinephrine transporters, as well as many receptors and ion channels. ML352 exhibited noncompetitive choline uptake inhibition in intact cells and synaptosomes and reduced the apparent density of hemicholinium-3 (HC-3) binding sites in membrane assays, suggesting allosteric transporter interactions. Pharmacokinetic studies revealed limited in vitro metabolism and significant CNS penetration, with features predicting rapid clearance. ML352 represents a novel, potent, and specific tool for the manipulation of CHT, providing a possible platform for the development of cholinergic imaging and therapeutic agents.


Asunto(s)
Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Proteínas de Transporte de Membrana/metabolismo , Sinaptosomas/efectos de los fármacos , Animales , Benzamidas/química , Benzamidas/farmacocinética , Benzamidas/farmacología , Colina/farmacología , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Células HEK293 , Hemicolinio 3/farmacología , Humanos , Isoxazoles/química , Isoxazoles/farmacocinética , Isoxazoles/farmacología , Masculino , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/genética , Proteínas de Transporte de Membrana/genética , Ratones , Ratones Endogámicos C57BL , Modelos Biológicos , Mutación/genética , Inhibición Neural/efectos de los fármacos , Prosencéfalo/citología , Unión Proteica/efectos de los fármacos , Unión Proteica/genética , Ratas , Ratas Sprague-Dawley , Sinaptosomas/metabolismo
19.
Nucleic Acids Res ; 42(21): 13353-69, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25378320

RESUMEN

The cold shock domain is one of the most highly conserved motifs between bacteria and higher eukaryotes. Y-box-binding proteins represent a subfamily of cold shock domain proteins with pleiotropic functions, ranging from transcription in the nucleus to translation in the cytoplasm. These proteins have been investigated in all major model organisms except Caenorhabditis elegans. In this study, we set out to fill this gap and present a functional characterization of CEYs, the C. elegans Y-box-binding proteins. We find that, similar to other organisms, CEYs are essential for proper gametogenesis. However, we also report a novel function of these proteins in the formation of large polysomes in the soma. In the absence of the somatic CEYs, polysomes are dramatically reduced with a simultaneous increase in monosomes and disomes, which, unexpectedly, has no obvious impact on animal biology. Because transcripts that are enriched in polysomes in wild-type animals tend to be less abundant in the absence of CEYs, our findings suggest that large polysomes might depend on transcript stabilization mediated by CEY proteins.


Asunto(s)
Proteínas de Caenorhabditis elegans/fisiología , Polirribosomas/metabolismo , Proteínas de Unión al ARN/fisiología , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/crecimiento & desarrollo , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/análisis , Citoplasma/química , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/análisis , Ribonucleoproteínas/química
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