RESUMEN
The placenta is vital to the health and development of the fetus, serving to deliver oxygen and nutrients, facilitate the removal of waste products, and provide a barrier to pathogens and other harmful substances present in the maternal circulation. When these processes fail to operate normally, they can lead to complications of pregnancy such as preeclampsia or fetal growth restriction. The development of novel therapeutics for the mother, fetus, or placenta requires a mechanistic understanding of the development and functions of the placenta. For the obstetric clinician, being able to monitor the placenta throughout the pregnancy and to measure the impact of any treatment modality on the mother and the developing fetus are essential for providing the best possible care. The Eunice Kennedy Shriver National Institute of Child Health and Human Development at the National Institutes of Health has been a longtime supporter of research on the placenta. In 2014, the Human Placenta Project was initiated to help to drive an understanding of the biology of the human placenta and to facilitate the development of novel tools and approaches to allow for safe, noninvasive, real-time assessment of the placenta across pregnancy. Those efforts, along with others from around the globe, are showing promise. Although not yet ready for clinical application, these advances are moving the field forward and are certain to have a tremendous impact on the development and assessment of therapeutics designed for treating conditions of pregnancy.
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Placenta/fisiología , Embarazo/fisiología , Investigación Biomédica , Femenino , Retardo del Crecimiento Fetal , Feto , Humanos , Placenta/fisiopatología , Preeclampsia/fisiopatología , Complicaciones del Embarazo/terapiaRESUMEN
PURPOSE OF REVIEW: Myasthenia gravis is an autoimmune disease that commonly affects the palpebral and extraocular muscles. Ocular myasthenia gravis (OMG) is a variant of the disease that is confined to the ocular muscles but frequently becomes generalized over time. The diagnosis of OMG is often challenging but both clinical and laboratory findings are helpful in confirming the clinical suspicion. This review provides an update on the diagnostic approach and therapeutic options for OMG. RECENT FINDINGS: Antimuscle-specific tyrosine kinase and LDL-related receptor-related protein 4 are newly available serologic testing for myasthenia gravis that can help in increasing the diagnostic sensitivity of OMG. They should be included to the diagnostic algorithm of OMG in appropriate clinical situations. SUMMARY: OMG remains a primarily clinical diagnosis, but recent advances in laboratory testing can improve the diagnostic accuracy and should be used in appropriate clinical settings. The mainstay of treatment for OMG has not significantly changed over the past years, but the increasing availability of steroid-sparing agents improved the disease control while minimizing steroid-induced complications.
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Miastenia Gravis/diagnóstico , Miastenia Gravis/tratamiento farmacológico , Técnicas de Diagnóstico Oftalmológico , Glucocorticoides/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Músculos Oculomotores/patologíaRESUMEN
We model the luminosity-dependent projected and redshift-space two-point correlation functions (2PCFs) of the Sloan Digital Sky Survey (SDSS) Data Release 7 Main galaxy sample, using the halo occupation distribution (HOD) model and the subhalo abundance matching (SHAM) model and its extension. All the models are built on the same high-resolution N-body simulations. We find that the HOD model generally provides the best performance in reproducing the clustering measurements in both projected and redshift spaces. The SHAM model with the same halo-galaxy relation for central and satellite galaxies (or distinct haloes and subhaloes), when including scatters, has a best-fitting χ2/dof around 2-3. We therefore extend the SHAM model to the subhalo clustering and abundance matching (SCAM) by allowing the central and satellite galaxies to have different galaxy-halo relations. We infer the corresponding halo/subhalo parameters by jointly fitting the galaxy 2PCFs and abundances and consider subhaloes selected based on three properties, the mass Macc at the time of accretion, the maximum circular velocity Vacc at the time of accretion, and the peak maximum circular velocity Vpeak over the history of the subhaloes. The three subhalo models work well for luminous galaxy samples (with luminosity above L*). For low-luminosity samples, the Vacc model stands out in reproducing the data, with the Vpeak model slightly worse, while the Macc model fails to fit the data. We discuss the implications of the modelling results.
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The cold dark matter (CDM) cosmological model has been remarkably successful in explaining cosmic structure over an enormous span of redshift, but it has faced persistent challenges from observations that probe the innermost regions of dark matter halos and the properties of the Milky Way's dwarf galaxy satellites. We review the current observational and theoretical status of these "small-scale controversies." Cosmological simulations that incorporate only gravity and collisionless CDM predict halos with abundant substructure and central densities that are too high to match constraints from galaxy dynamics. The solution could lie in baryonic physics: Recent numerical simulations and analytical models suggest that gravitational potential fluctuations tied to efficient supernova feedback can flatten the central cusps of halos in massive galaxies, and a combination of feedback and low star formation efficiency could explain why most of the dark matter subhalos orbiting the Milky Way do not host visible galaxies. However, it is not clear that this solution can work in the lowest mass galaxies, where discrepancies are observed. Alternatively, the small-scale conflicts could be evidence of more complex physics in the dark sector itself. For example, elastic scattering from strong dark matter self-interactions can alter predicted halo mass profiles, leading to good agreement with observations across a wide range of galaxy mass. Gravitational lensing and dynamical perturbations of tidal streams in the stellar halo provide evidence for an abundant population of low-mass subhalos in accord with CDM predictions. These observational approaches will get more powerful over the next few years.
RESUMEN
Intravascular large B-cell lymphoma, also known as angiotrophic large cell lymphoma, is a rare disorder where neoplastic lymphoid cells proliferate within the walls of small- to medium-sized blood vessels. Peripheral neuropathy and other neurological manifestations, including stroke and dementia, are common, but cases of isolated multiple mononeuropathies in the absence of systemic symptoms are distinctly rare. We present an unusual case of biopsy-proved angiotrophic large cell lymphoma presenting exclusively with multiple mononeuropathies.
Asunto(s)
Linfoma de Células B Grandes Difuso/complicaciones , Mononeuropatías/complicaciones , Mononeuropatías/diagnóstico , Humanos , Masculino , Persona de Mediana EdadRESUMEN
We report the discovery of piperazine urea based compound 1, a potent, selective, orally bioavailable melanocortin subtype-4 receptor partial agonist. Compound 1 shows anti-obesity efficacy without potentiating erectile activity in the rodent models.
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Piperazinas/química , Receptor de Melanocortina Tipo 4/agonistas , Urea/análogos & derivados , Administración Oral , Animales , Disponibilidad Biológica , Modelos Animales de Enfermedad , Perros , Evaluación Preclínica de Medicamentos , Ingestión de Alimentos/efectos de los fármacos , Haplorrinos , Ratones , Obesidad/tratamiento farmacológico , Piperazinas/farmacocinética , Piperazinas/uso terapéutico , Ratas , Ratas Sprague-Dawley , Receptor de Melanocortina Tipo 4/genética , Receptor de Melanocortina Tipo 4/metabolismo , Relación Estructura-Actividad , Urea/química , Urea/farmacocinética , Urea/uso terapéuticoRESUMEN
We report an SAR study of MC4R analogs containing spiroindane heterocyclic privileged structures. Compound 26 with N-Me-1,2,4-triazole moiety possesses exceptional potency at MC4R and potent anti-obesity efficacy in a mouse model. However, the efficacy is not completely mediated through MC4R. Additional SAR studies led to the discovery of compound 32, which is more potent at MC4R. Compound 32 demonstrates MC4R mediated anti-obesity efficacy in rodent models.
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Obesidad/tratamiento farmacológico , Receptor de Melanocortina Tipo 4/agonistas , Triazoles/farmacología , Animales , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Ratones , Ratones Noqueados , Estructura Molecular , Ratas , Receptor de Melanocortina Tipo 4/genética , Relación Estructura-Actividad , Triazoles/química , Triazoles/uso terapéuticoRESUMEN
Design, syntheses and structure-activity relationships of N-acetylated piperazine privileged structures containing MC4R agonist compounds were described. The most potent derivatives were low nM MC4R selective full agonists. Several compounds from the series had modest pharmacokinetic properties.
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Ligandos , Receptor de Melanocortina Tipo 4/agonistas , Animales , Humanos , Piperazina , Piperazinas/síntesis química , Piperazinas/química , Piperazinas/farmacocinética , Ratas , Ratas Sprague-Dawley , Receptor de Melanocortina Tipo 4/metabolismo , Relación Estructura-ActividadRESUMEN
We report a series of potent and selective MC4R agonists based on spiroindane amide privileged structures for potential treatments of obesity. Among the synthetic methods used, Method C allows rapid synthesis of the analogs. The series of compounds can afford high potency on MC4R as well as good rodent pharmacokinetic profiles. Compound 1r (MK-0489) demonstrates MC4R mediated reduction of food intake and body weight in mouse models. Compound 1r is efficacious in 14-day diet-induced obese (DIO) rat models.
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Amidas/química , Fármacos Antiobesidad/química , Obesidad/tratamiento farmacológico , Pirrolidinas/química , Receptor de Melanocortina Tipo 4/agonistas , Compuestos de Espiro/química , Amidas/farmacocinética , Amidas/uso terapéutico , Animales , Fármacos Antiobesidad/farmacocinética , Fármacos Antiobesidad/uso terapéutico , Peso Corporal/efectos de los fármacos , Humanos , Ratones , Ratones Noqueados , Pirrolidinas/farmacocinética , Pirrolidinas/uso terapéutico , Ratas , Ratas Sprague-Dawley , Receptor de Melanocortina Tipo 4/metabolismo , Compuestos de Espiro/farmacocinética , Compuestos de Espiro/uso terapéutico , Relación Estructura-ActividadRESUMEN
Design, synthesis, and SAR of a series of 3H-spiro[isobenzofuran-1,4'-piperidine] based compounds as potent, selective and orally bioavailable melanocortin subtype-4 receptor (MC4R) agonists are disclosed.
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Piperidinas/química , Receptor de Melanocortina Tipo 4/agonistas , Administración Oral , Animales , Encéfalo/metabolismo , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos , Humanos , Conformación Molecular , Piperidinas/síntesis química , Piperidinas/farmacología , Ratas , Ratas Sprague-Dawley , Receptor de Melanocortina Tipo 4/metabolismo , Compuestos de Espiro/química , Relación Estructura-ActividadRESUMEN
We report the design, synthesis and properties of spiroindane based compound 1, a potent, selective, orally bioavailable, non-peptide melanocortin subtype-4 receptor agonist. Compound 1 shows excellent erectogenic activity in the rodent models.
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Disfunción Eréctil/tratamiento farmacológico , Indanos/química , Indanos/uso terapéutico , Receptor de Melanocortina Tipo 4/agonistas , Receptor de Melanocortina Tipo 4/metabolismo , Compuestos de Espiro/química , Compuestos de Espiro/uso terapéutico , Animales , Células CHO , Cricetinae , Cricetulus , Perros , Haplorrinos , Humanos , Indanos/farmacocinética , Indanos/farmacología , Masculino , Ratones , Estructura Molecular , Unión Proteica , Ratas , Compuestos de Espiro/farmacocinética , Compuestos de Espiro/farmacología , Relación Estructura-ActividadRESUMEN
OBJECTIVE: Randomized, blinded trial of intramuscular gene transfer using plasmid vascular endothelial growth factor (VEGF) to treat diabetic polyneuropathy. METHODS: Diabetic patients with polyneuropathy were randomized to receive a VEGF-to-placebo ratio of 3:1. Three sets of injections were given at eight standardized sites adjacent to the sciatic, peroneal, and tibial nerves of one leg. Primary outcomes were change in symptom score at 6 months and a prespecified overall clinical and electrophysiological improvement score. Secondary outcomes were differences in symptoms, examination scores, visual analog pain scale, nerve conduction, and quantitative sensory testing. RESULTS: Thirty-nine patients received plasmid VEGF and 11 received placebo. Mean symptom score improved in both legs at 6 months, favoring VEGF over placebo (-1.2 +/- 0.5 vs -0.9 +/- 0.5; p < 0.01 after adjustment for change in the untreated leg) and compared with the untreated leg (-0.7 +/- 0.5; p = 0.02). The region of sensory loss and visual analog pain scale improved in the treated group (-1.5 vs -0.5; p = 0.01). Twelve of 39 VEGF versus 2 of 11 placebo patients met criterion for overall improvement. Other measures including nerve conduction potentials did not improve. There were 84 adverse events in VEGF patients, and 22 were serious; there were 51 events in placebo patients, and 2 were serious. INTERPRETATION: Intramuscular plasmid VEGF gene transfer improved diabetic neuropathic symptoms, meeting primary end-point criteria for efficacy but not affecting most secondary measures. Treatment was associated with more serious adverse events that did not reach statistical significance. These results are not conclusive but may justify further clinical study.
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Neuropatías Diabéticas/terapia , Técnicas de Transferencia de Gen , Terapia Genética/métodos , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/uso terapéutico , Anciano , Estudios de Cohortes , Neuropatías Diabéticas/metabolismo , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Conducción Nerviosa/genética , Dimensión del Dolor , Nervios Periféricos/fisiopatología , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
Discovery of a series of tert-butyl pyrrolidine derived, potent and orally bioavailable melanocortin receptor subtype-4 (MC4R) selective modulators is disclosed.
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Pirrolidinas/síntesis química , Pirrolidinas/farmacocinética , Receptor de Melanocortina Tipo 4/agonistas , Administración Oral , Humanos , Estructura Molecular , Estereoisomerismo , Relación Estructura-Actividad , TelomerasaRESUMEN
SAR about the piperidine core in a series of MC4R agonists is described. A number of alkyl substituents that furnish compounds with good affinity and functional potency are reported.
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Alcanos/farmacología , Piperidinas/química , Piperidinas/farmacología , Receptor de Melanocortina Tipo 4/agonistas , Receptor de Melanocortina Tipo 4/metabolismo , Alcanos/síntesis química , Alcanos/química , Amidas/química , Humanos , Estructura Molecular , Nitrilos/química , Piperidinas/síntesis química , Relación Estructura-Actividad , Tetrazoles/químicaRESUMEN
Toxic neuropathy represents an important clinical problem in the use of the chemotherapeutic substances Taxol and thalidomide. Sensory neuropathy has a high incidence, lacks an effective treatment and is the dose-limiting factor for these drugs. The pathogenic basis of these neuropathies is unknown. We investigated the hypothesis that the experimental toxic neuropathies from Taxol and thalidomide results from destruction of vasa nervorum and can be reversed by the administration of an angiogenic cytokine. In animal models of Taxol- and thalidomide-induced neuropathy, nerve blood flow has been attenuated and the number of vasa nervorum has been reduced. Intramuscular gene transfer of naked plasmid DNA encoding VEGF-1 administered in parallel with Taxol injections completely inhibited deterioration of nerve function and diminution of the peripheral nerve vasculature. Gene therapy in animals with established Taxol- or thalidomide-induced neuropathies resulted in recovery of vascularity and improved nerve electrophysiology. These findings implicate microvascular damage as the basis for toxic neuropathy and suggest that angiogenic growth factors may constitute a novel treatment for this disorder.
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Neovascularización Patológica/tratamiento farmacológico , Paclitaxel/farmacología , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Talidomida/farmacología , Vasa Nervorum/efectos de los fármacos , Vasa Nervorum/lesiones , Factor A de Crecimiento Endotelial Vascular/farmacología , Animales , Apoptosis/efectos de los fármacos , Células Cultivadas , Quimioterapia Combinada , Electrofisiología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/enzimología , Humanos , Inyecciones Intramusculares , Lectinas/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Enfermedades del Sistema Nervioso Periférico/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Plásmidos/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Sprague-Dawley , Circulación RenalRESUMEN
OBJECTIVE: This study evaluated validity and reliability of automated median and ulnar sensory nerve conduction study (NCS) measurements by the NC-stat. METHODS: Median and ulnar distal sensory latencies (DSL) and amplitudes (SNAP) were measured in sixty subjects with the NC-stat and by a neurologist (reference) using traditional instrumentation. The median-ulnar DSL differences (MUD) was calculated. Validity was quantified by the Pearson correlation. Reliability was evaluated by the intraclass correlation coefficient (ICC), Bland-Altman analysis, and inter-rater agreement of MUD abnormalities. RESULTS: As a result of differences in electrode placement, NC-stat and reference mean values had systematic differences. The correlation ranged from 0.70 (ulnar DSL) to 0.91 (median DSL). The ICC ranged from 0.69 (ulnar DSL) to 0.91 (median DSL). In Bland-Altman analysis of DSLs, NC-stat measurements had a bias of 0.56 ms (median) and 0.31 ms (ulnar) and precision of 0.31 and 0.30 ms. Inter-rater agreement for MUD abnormalities was 93.8% (raw) and 0.80 (Kappa). CONCLUSIONS: NC-stat validity and reliability metrics were similar to traditional NCS. Use of the NC-stat would require applicable reference ranges. SIGNIFICANCE: NC-stat median and ulnar NCS are valid and reliable. This device may be useful for increasing availability of NCS when clinically appropriate.
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Estimulación Eléctrica/instrumentación , Estimulación Eléctrica/métodos , Nervio Mediano/fisiopatología , Conducción Nerviosa/fisiología , Enfermedades del Sistema Nervioso Periférico/fisiopatología , Nervio Cubital/fisiopatología , Potenciales de Acción/fisiología , Potenciales de Acción/efectos de la radiación , Adolescente , Adulto , Anciano , Electrodos , Electromiografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción/fisiología , Tiempo de Reacción/efectos de la radiación , Valores de Referencia , Reproducibilidad de los Resultados , Estadística como AsuntoRESUMEN
Design and synthesis of potent MC4 selective agonists based on cyclohexylpiperidine derived cyclic urea, oxazolidinones, and sulfonamide based privileged structures are disclosed.
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Diseño de Fármacos , Receptor de Melanocortina Tipo 4/agonistas , Receptor de Melanocortina Tipo 4/metabolismo , Humanos , Ligandos , Estructura Molecular , Sensibilidad y Especificidad , Relación Estructura-Actividad , Especificidad por SustratoRESUMEN
Specific interactions of human melanocortin-4 receptor (hMC4R) with its nonpeptide and peptide agonists were studied using alanine-scanning mutagenesis. The binding affinities and potencies of two synthetic, small-molecule agonists (THIQ, MB243) were strongly affected by substitutions in transmembrane alpha-helices (TM) 2, 3, 6, and 7 (residues Glu(100), Asp(122), Asp(126), Phe(261), His(264), Leu(265), and Leu(288)). In addition, a I129A mutation primarily affected the binding and potency of THIQ, while F262A, W258A, Y268A mutations impaired interactions with MB243. By contrast, binding affinity and potency of the linear peptide agonist NDP-MSH were substantially reduced only in D126A and H264A mutants. Three-dimensional models of receptor-ligand complexes with their agonists were generated by distance-geometry using the experimental, homology-based, and other structural constraints, including interhelical H-bonds and two disulfide bridges (Cys(40)-Cys(279), Cys(271)-Cys(277)) of hMC4R. In the models, all pharmacophore elements of small-molecule agonists are spatially overlapped with the corresponding key residues (His(6), d-Phe(7), Arg(8), and Trp(9)) of the linear peptide: their charged amine groups interact with acidic residues from TM2 and TM3, similar to His(6) and Arg(6) of NDP-MSH; their substituted piperidines mimic Trp(9) of the peptide and interact with TM5 and TM6, while the d-Phe aromatic rings of all three agonists contact with Leu(133), Trp(258), and Phe(261) residues.
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Péptidos/farmacología , Receptor de Melanocortina Tipo 4/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , AMP Cíclico/farmacología , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Piperazinas/farmacología , Piperidinas/farmacología , Estructura Secundaria de Proteína , Receptor de Melanocortina Tipo 4/agonistas , Receptor de Melanocortina Tipo 4/química , Receptor de Melanocortina Tipo 4/efectos de los fármacos , Proteínas Recombinantes/química , Proteínas Recombinantes/efectos de los fármacos , Proteínas Recombinantes/metabolismo , Rodopsina/química , Alineación de Secuencia , Homología de Secuencia de Aminoácido , TransfecciónRESUMEN
The melanocortin subtype-4 receptor (MC4R) has been implicated in the control of feeding behavior and body weight regulation. A series of tetrapeptides, based on Tic-DPhe-Arg-Trp-NH2-a mimic of the putative message sequence "His-Phe-Arg-Trp" and modified at the DPhe position, were prepared and pharmacologically characterized for potency and selectivity. Substitution of His with Tic gave peptides with significant increases in selectivity. The effects of the substitution pattern of DPhe were investigated and it has significant influences on potency and the level of the maximum cAMP accumulation. Intracerebroventricular administration of peptide 10 induced significant inhibition of cumulative overnight food intake and feeding duration in rats.