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1.
J Neurosci ; 38(11): 2780-2795, 2018 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-29459374

RESUMEN

A homozygous nonsense mutation in the cereblon (CRBN) gene results in autosomal recessive, nonsyndromic intellectual disability that is devoid of other phenotypic features, suggesting a critical role of CRBN in mediating learning and memory. In this study, we demonstrate that adult male Crbn knock-out (CrbnKO) mice exhibit deficits in hippocampal-dependent learning and memory tasks that are recapitulated by focal knock-out of Crbn in the adult dorsal hippocampus, with no changes in social or repetitive behavior. Cellular studies identify deficits in long-term potentiation at Schaffer collateral CA1 synapses. We further show that Crbn is robustly expressed in the mouse hippocampus and CrbnKO mice exhibit hyperphosphorylated levels of AMPKα (Thr172). Examination of processes downstream of AMP-activated protein kinase (AMPK) finds that CrbnKO mice have a selective impairment in mediators of the mTORC1 translation initiation pathway in parallel with lower protein levels of postsynaptic density glutamatergic proteins and higher levels of excitatory presynaptic markers in the hippocampus with no change in markers of the unfolded protein response or autophagy pathways. Acute pharmacological inhibition of AMPK activity in adult CrbnKO mice rescues learning and memory deficits and normalizes hippocampal mTORC1 activity and postsynaptic glutamatergic proteins without altering excitatory presynaptic markers. Thus, this study identifies that loss of Crbn results in learning, memory, and synaptic defects as a consequence of exaggerated AMPK activity, inhibition of mTORC1 signaling, and decreased glutamatergic synaptic proteins. Thus, CrbnKO mice serve as an ideal model of intellectual disability to further explore molecular mechanisms of learning and memory.SIGNIFICANCE STATEMENT Intellectual disability (ID) is one of the most common neurodevelopmental disorders. The cereblon (CRBN) gene has been linked to autosomal recessive, nonsyndromic ID, characterized by an intelligence quotient between 50 and 70 but devoid of other phenotypic features, making cereblon an ideal protein for the study of the fundamental aspects of learning and memory. Here, using the cereblon knock-out mouse model, we show that cereblon deficiency disrupts learning, memory, and synaptic function via AMP-activated protein kinase hyperactivity, downregulation of mTORC1, and dysregulation of excitatory synapses, with no changes in social or repetitive behaviors, consistent with findings in the human population. This establishes the cereblon knock-out mouse as a model of pure ID without the confounding behavioral phenotypes associated with other current models of ID.


Asunto(s)
Discapacidad Intelectual/genética , Discapacidad Intelectual/fisiopatología , Discapacidades para el Aprendizaje/genética , Discapacidades para el Aprendizaje/fisiopatología , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Trastornos de la Memoria/genética , Trastornos de la Memoria/fisiopatología , Proteínas del Tejido Nervioso/genética , Proteínas Adaptadoras Transductoras de Señales , Animales , Región CA1 Hipocampal/fisiopatología , Potenciales Postsinápticos Excitadores/genética , Hipocampo/metabolismo , Hipocampo/fisiopatología , Discapacidad Intelectual/tratamiento farmacológico , Discapacidades para el Aprendizaje/tratamiento farmacológico , Potenciación a Largo Plazo/genética , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina/biosíntesis , Trastornos de la Memoria/tratamiento farmacológico , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Inhibidores de Proteínas Quinasas/uso terapéutico , Conducta Social
2.
BMC Health Serv Res ; 19(1): 919, 2019 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-31783848

RESUMEN

BACKGROUND: Primary care providers (PCPs) are typically the first to screen and evaluate patients for neurocognitive disorders (NCDs), including mild cognitive impairment and dementia. However, data on PCP attitudes and evaluation and management practices are sparse. Our objective was to quantify perspectives and behaviors of PCPs and neurologists with respect to NCD evaluation and management. METHODS: A cross-sectional survey with 150 PCPs and 50 neurologists in the United States who evaluated more than 10 patients over age 55 per month. The 51-item survey assessed clinical practice characteristics, and confidence, perceived barriers, and typical practices when diagnosing and managing patients with NCDs. RESULTS: PCPs and neurologists reported similar confidence and approaches to general medical care and laboratory testing. Though over half of PCPs performed cognitive screening or referred patients for cognitive testing in over 50% of their patients, only 20% reported high confidence in interpreting results of cognitive tests. PCPs were more likely to order CT scans than MRIs, and only 14% of PCPs reported high confidence interpreting brain imaging findings, compared to 70% of specialists. Only 21% of PCPs were highly confident that they correctly recognized when a patient had an NCD, and only 13% were highly confident in making a specific NCD diagnosis (compared to 72 and 44% for neurologists, both p < 0.001). A quarter of all providers identified lack of familiarity with diagnostic criteria for NCD syndromes as a barrier to clinical practice. CONCLUSIONS: This study demonstrates how PCPs approach diagnosis and management of patients with NCDs, and identified areas for improvement in regards to cognitive testing and neuroimaging. This study also identified all providers' lack of familiarity with published diagnostic criteria for NCD syndromes. These findings may inform the development of new policies and interventions to help providers improve the efficacy of their decision processes and deliver better quality care to patients with NCDs.


Asunto(s)
Demencia/diagnóstico , Pautas de la Práctica en Medicina/estadística & datos numéricos , Atención Primaria de Salud/métodos , Estudios Transversales , Demencia/terapia , Humanos , Examen Neurológico/estadística & datos numéricos , Atención Primaria de Salud/estadística & datos numéricos , Derivación y Consulta/estadística & datos numéricos , Estados Unidos
3.
J Nurs Care Qual ; 34(3): 203-209, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30550493

RESUMEN

BACKGROUND: Despite its high prevalence, malnutrition in hospitalized patients often goes unrecognized and undertreated. LOCAL PROBLEM: A hospital system sought to improve nutrition care by implementing a quality improvement initiative. Nurses screened patients upon admission using the Malnutrition Screening Tool and initiated oral nutrition supplements for patients at risk. METHODS: We retrospectively reviewed the medical records of 20 697 adult patients to determine whether early initiation of nutrition therapy had reduced hospital length of stay and 30-day readmission rates. RESULTS: We found the average time from hospital admission to oral nutrition supplement initiation was reduced by 20 hours (20.8%) after the quality improvement initiative was introduced (P < .01). Length of stay decreased 0.88 days (P < .05) more for patients at nutritional risk than patients not at nutritional risk; the probability of 30-day hospital readmission did not differ between groups. CONCLUSION: These results highlight the importance of adequate nutrition screening, diagnosis, and treatment for hospitalized patients.


Asunto(s)
Apoyo Nutricional/normas , Mejoramiento de la Calidad/normas , Adulto , Anciano , Femenino , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Desnutrición/dietoterapia , Desnutrición/prevención & control , Tamizaje Masivo/métodos , Persona de Mediana Edad , Apoyo Nutricional/métodos , Readmisión del Paciente/estadística & datos numéricos , Mejoramiento de la Calidad/tendencias , Estudios Retrospectivos
4.
Am J Hum Genet ; 94(3): 462-9, 2014 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-24530202

RESUMEN

Copy-number variations cause genomic disorders. Triplications, unlike deletions and duplications, are poorly understood because of challenges in molecular identification, the choice of a proper model system for study, and awareness of their phenotypic consequences. We investigated the genomic disorder Charcot-Marie-Tooth disease type 1A (CMT1A), a dominant peripheral neuropathy caused by a 1.4 Mb recurrent duplication occurring by nonallelic homologous recombination. We identified CMT1A triplications in families in which the duplication segregates. The triplications arose de novo from maternally transmitted duplications and caused a more severe distal symmetric polyneuropathy phenotype. The recombination that generated the triplication occurred between sister chromatids on the duplication-bearing chromosome and could accompany gene conversions with the homologous chromosome. Diagnostic testing for CMT1A (n = 20,661 individuals) identified 13% (n = 2,752 individuals) with duplication and 0.024% (n = 5 individuals) with segmental tetrasomy, suggesting that triplications emerge from duplications at a rate as high as ~1:550, which is more frequent than the rate of de novo duplication. We propose that individuals with duplications are predisposed to acquiring triplications and that the population prevalence of triplication is underascertained.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/epidemiología , Enfermedad de Charcot-Marie-Tooth/genética , Enfermedad de Charcot-Marie-Tooth/fisiopatología , Duplicación de Gen , Alelos , Variaciones en el Número de Copia de ADN , Femenino , Dosificación de Gen , Humanos , Masculino , Repeticiones de Microsatélite , Atrofia Muscular/patología , Hibridación de Ácido Nucleico , Linaje , Fenotipo , Polineuropatías/genética , Recombinación Genética
5.
Hum Mutat ; 37(1): 127-34, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26467025

RESUMEN

We developed a rules-based scoring system to classify DNA variants into five categories including pathogenic, likely pathogenic, variant of uncertain significance (VUS), likely benign, and benign. Over 16,500 pathogenicity assessments on 11,894 variants from 338 genes were analyzed for pathogenicity based on prediction tools, population frequency, co-occurrence, segregation, and functional studies collected from internal and external sources. Scores were calculated by trained scientists using a quantitative framework that assigned differential weighting to these five types of data. We performed descriptive and comparative statistics on the dataset and tested interobserver concordance among the trained scientists. Private variants defined as variants found within single families (n = 5,182), were either VUS (80.5%; n = 4,169) or likely pathogenic (19.5%; n = 1,013). The remaining variants (n = 6,712) were VUS (38.4%; n = 2,577) or likely benign/benign (34.7%; n = 2,327) or likely pathogenic/pathogenic (26.9%, n = 1,808). Exact agreement between the trained scientists on the final variant score was 98.5% [95% confidence interval (CI) (98.0, 98.9)] with an interobserver consistency of 97% [95% CI (91.5, 99.4)]. Variant scores were stable and showed increasing odds of being in agreement with new data when re-evaluated periodically. This carefully curated, standardized variant pathogenicity scoring system provides reliable pathogenicity scores for DNA variants encountered in a clinical laboratory setting.


Asunto(s)
Biología Computacional/métodos , Predisposición Genética a la Enfermedad , Variación Genética , Genómica/métodos , Programas Informáticos , Humanos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Navegador Web
6.
Br J Ophthalmol ; 108(4): 495-505, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-37940365

RESUMEN

Stargardt macular dystrophy (Stargardt disease; STGD1; OMIM 248200) is the most prevalent inherited macular dystrophy. STGD1 is an autosomal recessive disorder caused by multiple pathogenic sequence variants in the large ABCA4 gene (OMIM 601691). Major advances in understanding both the clinical and molecular features, as well as the underlying pathophysiology, have culminated in many completed, ongoing and planned human clinical trials of novel therapies.The aims of this concise review are to describe (1) the detailed phenotypic and genotypic characteristics of the disease, multimodal imaging findings, natural history of the disease, and pathogenesis, (2) the multiple avenues of research and therapeutic intervention, including pharmacological, cellular therapies and diverse types of genetic therapies that have either been investigated or are under investigation and (3) the exciting novel therapeutic approaches on the translational horizon that aim to treat STGD1 by replacing the entire 6.8 kb ABCA4 open reading frame.


Asunto(s)
Degeneración Macular , Humanos , Enfermedad de Stargardt , Fenotipo , Mutación , Degeneración Macular/diagnóstico , Degeneración Macular/genética , Degeneración Macular/terapia , Genotipo , Transportadoras de Casetes de Unión a ATP/genética
7.
Am J Hum Genet ; 87(5): 643-54, 2010 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-21070897

RESUMEN

The study of inherited retinal diseases has advanced our knowledge of the cellular and molecular mechanisms involved in sensory neural signaling. Dysfunction of two specific sensory modalities, vision and proprioception, characterizes the phenotype of the rare, autosomal-recessive disorder posterior column ataxia and retinitis pigmentosa (PCARP). Using targeted DNA capture and high-throughput sequencing, we analyzed the entire 4.2 Mb candidate sequence on chromosome 1q32 to find the gene mutated in PCARP in a single family. Employing comprehensive bioinformatic analysis and filtering, we identified a single-nucleotide coding variant in the feline leukemia virus subgroup C cellular receptor 1 (FLVCR1), a gene encoding a heme-transporter protein. Sanger sequencing confirmed the FLVCR1 mutation in this family and identified different homozygous missense mutations located within the protein's transmembrane channel segment in two other unrelated families with PCARP. To determine whether the selective pathologic features of PCARP correlated with FLVCR1 expression, we examined wild-type mouse Flvcr1 mRNA levels in the posterior column of the spinal cord and the retina via quantitative real-time reverse-transcriptase PCR. The Flvcr1 mRNA levels were most abundant in the retina, followed by the posterior column of the spinal cord and other brain regions. These results suggest that aberrant FLVCR1 causes a selective degeneration of a subpopulation of neurons in the retina and the posterior columns of the spinal cord via dysregulation of heme or iron homeostasis. This finding broadens the molecular basis of sensory neural signaling to include common mechanisms that involve proprioception and vision.


Asunto(s)
Ataxia/genética , Proteínas de Transporte de Membrana/genética , Enfermedades Neurodegenerativas/genética , Receptores Virales/genética , Retinitis Pigmentosa/genética , Médula Espinal , Adolescente , Adulto , Niño , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Mutación , Linaje , Síndrome
8.
Appetite ; 71: 274-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24012965

RESUMEN

In the United States (US), based on the 2010 Affordable Care Act, restaurant chains and similar retail food establishments with 20 or more locations are required to begin implementing calorie information on their menus. As enacting of the law begins, it is important to understand its potential for improving consumers' healthful behaviors. Therefore, the objective of this study was to explore relationships among users of grocery nutrition labels and attitudes toward restaurant menu labeling, along with the caloric content of their restaurant menu selection. Study participants were surveyed and then provided identical mock restaurant menus with or without calories. Results found that participants who used grocery nutrition labels and believed they would make healthy menu selections with nutrition labels on restaurant menus made healthier menu selections, regardless of whether the menu displayed calories or not. Consumers' nutrition knowledge and behaviors gained from using grocery nutrition labels and consumers' desire for restaurants to provide nutrition menu labels have a positive effect on their choosing healthful restaurant menu items.


Asunto(s)
Etiquetado de Alimentos/legislación & jurisprudencia , Conocimientos, Actitudes y Práctica en Salud , Valor Nutritivo , Restaurantes , Ingestión de Energía , Etiquetado de Alimentos/métodos , Conductas Relacionadas con la Salud , Humanos , Modelos Logísticos , Encuestas y Cuestionarios , Estados Unidos
9.
Mol Metab ; 69: 101685, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36739970

RESUMEN

Over the past 40 years, there has been considerable research into the management and treatment of atherogenic lipid disorders. Although the majority of treatments and management strategies for cardiovascular disease (CVD) center around targeting low-density lipoprotein cholesterol (LDL-C), there is mounting evidence for the residual CVD risk attributed to high triglyceride (TG) and lipoprotein(a) (Lp(a)) levels despite the presence of lowered LDL-C levels. Among the biological mechanisms for clearing TG-rich lipoproteins, the VLDL receptor (VLDLR) plays a key role in the trafficking and metabolism of lipoprotein particles in multiple tissues, but it is not ordinarily expressed in the liver. Since VLDLR is capable of binding and internalizing apoE-containing TG-rich lipoproteins as well as Lp(a), hepatic VLDLR expression has the potential for promoting clearance of these atherogenic particles from the circulation and managing the residual CVD risk not addressed by current lipid lowering therapies. This review provides an overview of VLDLR function and the potential for developing a genetic medicine based on liver-targeted VLDLR gene expression.


Asunto(s)
Terapia Genética , Receptores de LDL , LDL-Colesterol , Receptores de LDL/metabolismo
10.
Biology (Basel) ; 11(4)2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35453745

RESUMEN

Euthanasia in zebrafish (Danio rerio) younger than 5 days post fertilization (dpf) is poorly described in the literature, and standardized protocols are lacking, most likely because larvae not capable of independent feeding are often not protected under national legislations. We assessed the euthanasia efficacy in laboratories in different countries of a one hour anesthetic overdose immersion with buffered lidocaine hydrochloride (1 g/L, with or without 50 mL/L of ethanol), buffered tricaine (1 g/L), clove oil (0.1%), benzocaine (1 g/L), or 2-phenoxyethanol (3 mL/L), as well as the efficacy of hypothermic shock (one hour immersion) and electrical stunning (for one minute), on zebrafish at <12 h post fertilization (hpf), 24 hpf, and 4 dpf. Based on the survival/recovery rates 24 h after treatment, the most effective methods were clove oil, lidocaine with ethanol, and electrical stunning. For 4 dpf larvae, signs of aversion during treatment demonstrated that all anesthetics, except lidocaine, induced aversive behavior. Therefore, the most suited euthanasic treatment was lidocaine hydrochloride 1 g/L, buffered with 2 g/L of sodium bicarbonate and mixed with 50 mL/L of ethanol, which euthanized both embryos and larvae in an efficient and stress-free manner. Electrical stunning also euthanized embryos and larvae efficiently and without signs of aversion; this method needs further assessment in other laboratories to draw firm conclusions.

11.
Biology (Basel) ; 10(11)2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34827125

RESUMEN

Zebrafish are often euthanized by overdose of anaesthesia. However, fish may have aversion towards some anaesthetics, and protocol efficacy varies between species. Using wild type adult Danio rerio, we assessed time to loss of opercular beat, righting, and startle reflexes during induction of anaesthetic overdose by either tricaine (0.5 g/L or 1 g/L), benzocaine (1 g/L), 2-phenoxyethanol (3 mL/L), clove oil (0.1%), isoeugenol (540 mg/L), lidocaine hydrochloride (1 g/L), or etomidate (50 mg/L). Initial screening demonstrated that benzocaine and buffered lidocaine hydrochloride achieved the fastest loss of reflexes. The rapid induction times were confirmed when retesting using larger batches of fish. The fastest induction was obtained with 1 g/L lidocaine hydrochloride buffered with 2 g/L NaHCO3, in which all adult zebrafish lost reflexes in less than 2 min. Next, we monitored signs of distress during benzocaine or buffered lidocaine hydrochloride overdose induction. The results indicated that buffered lidocaine hydrochloride caused significantly less aversive behaviors than benzocaine. Finally, we tested several buffers to refine the lidocaine hydrochloride immersion. The most efficient buffer for euthanasia induction using 1g/L lidocaine hydrochloride was 2 g/L NaHCO3 with 50 mL/L 96% ethanol, inducing immobility in less than 10 s and with only 2% of adult zebrafish displaying aversive behaviors during treatment.

12.
J Neurogenet ; 24(1): 18-26, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20131966

RESUMEN

A mild form of autosomal recessive, nonsyndromal intellectual disability (ARNSID) in humans is caused by a homozygous nonsense mutation in the cereblon gene (mutCRBN). Rodent crbn protein binds to the intracellular C-terminus of the large conductance Ca(2+)-activated K(+)channel (BK(Ca)). An mRNA variant (human SITE 2 INSERT or mouse strex) of the BK(Ca) gene (KCNMA1) that is normally expressed during embryonic development is aberrantly expressed in mutCRBN human lymphoblastoid cell lines (LCLs) as compared to wild-type (wt) LCLs. The present study analyzes the temporal and spatial distribution of crbn and kcnma1 mRNAs in the mouse brain by the quantitative real-time reverse transcriptase-polymerase chain reaction (qPCR). The spatial expression pattern of endogenous and exogenous crbn proteins is characterized by immunostaining. The results show that neocortical (CTX) crbn and kcnma1 mRNA expression increases from embryonic stages to adulthood. The strex mRNA variant is >3.5-fold higher in embryos and decreases rapidly postnatally. Mouse crbn mRNA is abundant in the cerebellum (CRBM), with less expression in the CTX, hippocampus (HC), and striatum (Str) in adult mice. The intracytoplasmic distribution of endogenous crbn protein in the mouse CRBM, CTX, HC, and Str is similar to the immunostaining pattern described previously for the BK(Ca) channel. Exogenous hemagglutinin (HA) epitope-tagged human wt- and mutCRBN proteins using cDNA transfection in HEK293T cell lines showed the same intracellular expression distribution as endogenous mouse crbn protein. The results suggest that mutCRBN may cause ARNSID by disrupting the developmental regulation of BK(Ca) in brain regions that are critical for memory and learning.


Asunto(s)
Encéfalo/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Péptido Hidrolasas/genética , Péptido Hidrolasas/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Envejecimiento/genética , Envejecimiento/metabolismo , Animales , Encéfalo/embriología , Encéfalo/crecimiento & desarrollo , Línea Celular , Preescolar , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/metabolismo , Discapacidades del Desarrollo/fisiopatología , Regulación del Desarrollo de la Expresión Génica/genética , Humanos , Inmunohistoquímica , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/genética , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/metabolismo , Ratones , Ratones Endogámicos C57BL , Mutación/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo , Transfección/métodos , Ubiquitina-Proteína Ligasas
13.
SAGE Open Med Case Rep ; 8: 2050313X20943068, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32742655

RESUMEN

The current standard of care for the treatment of flow-limiting calcific iliac artery disease is balloon angioplasty and subsequent stent placement. However, the presence of calcified lesions may prevent adequate stent expansion or impede the delivery of large bore devices, such as those for transcatheter aortic valve replacement or endovascular aneurysm repair implants. Plaque modification through vessel preparation with orbital atherectomy may enable stent expansion and subsequent proper large device delivery with low rates of procedural complications. A retrospective, single center, case series of 13 subjects treated with orbital atherectomy in iliac arteries to enable large bore device delivery was conducted. Patients were selected for treatment based on iliac artery disease or inability to deliver devices. The procedural complication rate was defined as the composite of flow-limiting dissection, perforation, slow flow, vessel closure, spasm, embolism, and thrombosis. Technical success was assessed as angiographic luminal gain and subsequent successful delivery of large bore devices through the treatment area, as well as freedom from procedural complications. Orbital atherectomy vessel preparation of severely calcified iliac artery lesions resulted in adequate stent expansion safely and enabled delivery of rigid/large profile devices. Further studies are warranted to evaluate patient selection criteria, as well as long-term efficacy and safety rates of orbital atherectomy in the iliac artery.

14.
Mol Cancer Ther ; 7(4): 818-28, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18413795

RESUMEN

AG-012986 is a multitargeted cyclin-dependent kinase (CDK) inhibitor active against CDK1, CDK2, CDK4/6, CDK5, and CDK9, with selectivity over a diverse panel of non-CDK kinases. Here, we report the potent antitumor efficacies of AG-012986 against multiple tumor lines in vitro and in vivo. AG-012986 showed antiproliferative activities in vitro with IC(50)s of <100 nmol/L in 14 of 18 tumor cell lines. In vivo, significant antitumor efficacy induced by AG-012986 was seen (tumor growth inhibition, >83.1%) in 10 of 11 human xenograft tumor models when administered at or near the maximum tolerated dose for 8 or 12 days. AG-012986 caused dose-dependent hypophosphorylation at Ser(795) of the retinoblastoma protein, cell cycle arrest, and apoptosis in vitro. Colony-forming assays indicated that the potency of AG-012986 substantially decreased with treatment time of <24 h. In vivo, AG-012986 also showed dose-dependent retinoblastoma Ser(795) hypophosphorylation, cell cycle arrest, decreased Ki-67 tumor staining, and apoptosis in conjunction with antitumor activity. Studies comparing i.p. bolus with s.c. implanted minipump dosing regimens revealed that in vivo efficacy correlated with the duration of minimally effective plasma levels rather than maximal drug plasma levels. Dosing optimization of AG-012986 provided guidance for selecting a treatment schedule to achieve the best antitumor efficacy while minimizing the risk of adverse side effects.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Benzamidas/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Tiazoles/farmacología , Animales , Benzamidas/farmacocinética , Western Blotting , Ciclo Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Ensayo de Unidades Formadoras de Colonias , Humanos , Técnicas para Inmunoenzimas , Etiquetado Corte-Fin in Situ , Ratones , Ratones Desnudos , Ratones SCID , Fosforilación/efectos de los fármacos , Proteína de Retinoblastoma/metabolismo , Tiazoles/farmacocinética , Distribución Tisular , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Neurogenetics ; 9(3): 219-23, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18414909

RESUMEN

A nonsense mutation (R419X) in the human cereblon gene [mutation (mut) CRBN] causes a mild type of autosomal recessive nonsyndromal mental retardation (ARNSMR). CRBN, a cytosolic protein, regulates the assembly and neuronal surface expression of large-conductance Ca(2+)-activated K(+) channels (BK(Ca)) in brain regions involved in memory and learning. Using the real-time quantitative polymerase chain reaction, we show that mut CRBN disturbs the development of adult brain BK(Ca) isoforms. These changes are predicted to result in BK(Ca) channels with a higher intracellular Ca(2+) sensitivity, faster activation, and slower deactivation kinetics. Such alterations may contribute to cognitive impairments in patients with mild ARNSMR.


Asunto(s)
Codón sin Sentido , Discapacidad Intelectual/genética , Discapacidad Intelectual/metabolismo , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/metabolismo , Péptido Hidrolasas/genética , Péptido Hidrolasas/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Adulto , Secuencia de Bases , Encéfalo/metabolismo , Estudios de Casos y Controles , Cartilla de ADN/genética , Femenino , Genes Recesivos , Humanos , Cinética , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/química , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/genética , Masculino , Reacción en Cadena de la Polimerasa , Ubiquitina-Proteína Ligasas
17.
J Am Geriatr Soc ; 66(1): 150-156, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29355911

RESUMEN

BACKGROUND/OBJECTIVES: Brief cognitive screens lack the sensitivity to detect mild cognitive impairment (MCI) or support differential diagnoses. The objective of this study was to validate the 10-minute, tablet-based University of California, San Francisco (UCSF) Brain Health Assessment (BHA) to overcome these limitations. DESIGN: Cross-sectional. SETTING: UCSF Memory and Aging Center. PARTICIPANTS: Older adults (N = 347) (neurologically healthy controls (n = 185), and individuals diagnosed with MCI (n = 99), dementia (n = 42), and as normal with concerns (n = 21)). MEASUREMENTS: The BHA includes subtests of memory, executive function and speed, visuospatial skills, and language and an optional informant survey. Participants completed the Montreal Cognitive Assessment (MoCA) and criterion-standard neuropsychological tests. Standardized structural 3T brain magnetic resonance imaging was performed in 145 participants. RESULTS: At a fixed 85% specificity rate, the BHA had 100% sensitivity to dementia and 84% to MCI; the MoCA had 75% sensitivity to dementia and 25% to MCI. The BHA had 83% sensitivity to MCI likely due to AD and 88% to MCI unlikely due to AD, and the MoCA had 58% sensitivity to MCI likely AD and 24% to MCI unlikely AD. The BHA subtests demonstrated moderate to high correlations with the criterion-standard tests from their respective cognitive domains. Memory test performance correlated with medial temporal lobe volumes; executive and speed with frontal, parietal, and basal ganglia volumes; and visuospatial with right parietal volumes. CONCLUSION: The BHA had excellent combined sensitivity and specificity to detect dementia and MCI, including MCI due to diverse etiologies. The subtests provide efficient, valid measures of neurocognition that are critical in making a differential diagnosis.


Asunto(s)
Encéfalo , Tamizaje Masivo , Trastornos Neurocognitivos/diagnóstico , Pruebas Neuropsicológicas/estadística & datos numéricos , Anciano , Estudios Transversales , Humanos , Imagen por Resonancia Magnética , San Francisco , Sensibilidad y Especificidad , Encuestas y Cuestionarios
18.
Adv Genomics Genet ; 8: 23-33, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-31031559

RESUMEN

BACKGROUND: Frontotemporal lobar degeneration (FTLD) is a leading cause of dementia, and elucidating its genetic underpinnings is critical. FTLD research centers typically recruit patient cohorts that are limited by the center's specialty and the ways in which its geographic location affects the ethnic makeup of research participants. Novel sources of data are needed to get population estimates of the contribution of variants in known FTLD-associated genes. METHODS: We compared FLTD-associated genetic variants in microtubule-associated protein tau (MAPT), progranulin (GRN), and chromosome nine open reading frame 72 (C9ORF72) from an academic research cohort and a commercial clinical genetics laboratory. Pathogenicity was assessed using guidelines of the American College of Medical Genetics and Genomics and a rule-based DNA variant assessment system. We conducted chart reviews on patients with novel or rare disease-associated variants. RESULTS: A total of 387 cases with FTLD-associated variants from the commercial (n=2,082) and 78 cases from the academic cohort (n=2,089) were included for analysis. In the academic cohort, the most frequent pathogenic variants were C9ORF72 expansions (63%, n=49), followed by GRN (26%, n=20) and MAPT (11%, n=9). Each gene's contribution to disease was similarly ranked in the commercial laboratory but differed in magnitude: C9ORF72 (89%, n=345), GRN (6%, n=24), and MAPT (5%, n=19). Of the 37 unique GRN/MAPT variants identified, only six were found in both cohorts. Clinicopathological data from patients in the academic cohort strengthened classification of two novel GRN variant as pathogenic (p.Pro166Leufs*2, p.Gln406*) and one GRN variant of unknown significance as a possible rare risk variant (p.Cys139Arg). CONCLUSION: Differences in gene frequencies and identification of unique pathogenic alleles in each cohort demonstrate the importance of data sharing between academia and community laboratories. Using shared data sources with well-characterized clinical phenotypes for individual variants can enhance interpretation of variant pathogenicity and inform clinical management of at-risk patients and families.

19.
Med Teach ; 29(6): e143-50, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17978961

RESUMEN

BACKGROUND: Gaps in the knowledge of general practitioners (GPs) in medical genetics prevent the effective utilization of genetic services and increase the risk of liability. Educators recommend that genetics should be integrated into existing teaching programs but the effectiveness of these types of programs is unknown. AIM: The objective of this study was to provide a 2-year educational program for GPs untrained in genetics and to document its impact on genetic knowledge and referrals to a genetic counselor (GC). METHODS: Eight genetic lectures series were given at quarterly intervals. Family practice residents received additional training in a genetics clinic, and participated in monthly seminars and bi-annual journal clubs. A pretest-post-test study design (n = 143) was used to evaluate the genetic knowledge of GPs. Post-test scores [mean (%) +/- SD; 76.1 +/- 16.8] showed significant improvement compared to pretest scores (61.9 +/- 19.1). The majority of participants (81%) indicated that the program would have an impact on their clinical practice. The number of referrals to a GC from GPs untrained in genetics did not change over the 2-year period of the program. CONCLUSION: The results suggest that an integrated educational program in genetics can enhance physicians' knowledge but may not alter referral patterns to a GC.


Asunto(s)
Educación Médica Continua , Asesoramiento Genético , Genética/educación , Conocimientos, Actitudes y Práctica en Salud , Médicos de Familia/educación , Derivación y Consulta/estadística & datos numéricos , Evaluación Educacional , Humanos , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud
20.
F1000Res ; 4: 53, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25901280

RESUMEN

This brief review of current research progress on Charcot-Marie-Tooth (CMT) disease is a summary of discussions initiated at the Hereditary Neuropathy Foundation (HNF) scientific advisory board meeting on November 7, 2014. It covers recent published and unpublished in vitro and in vivo research. We discuss recent promising preclinical work for CMT1A, the development of new biomarkers, the characterization of different animal models, and the analysis of the frequency of gene mutations in patients with CMT. We also describe how progress in related fields may benefit CMT therapeutic development, including the potential of gene therapy and stem cell research. We also discuss the potential to assess and improve the quality of life of CMT patients. This summary of CMT research identifies some of the gaps which may have an impact on upcoming clinical trials. We provide some priorities for CMT research and areas which HNF can support. The goal of this review is to inform the scientific community about ongoing research and to avoid unnecessary overlap, while also highlighting areas ripe for further investigation. The general collaborative approach we have taken may be useful for other rare neurological diseases.

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