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1.
Am J Hum Genet ; 108(5): 857-873, 2021 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-33961779

RESUMEN

The ALF transcription factor paralogs, AFF1, AFF2, AFF3, and AFF4, are components of the transcriptional super elongation complex that regulates expression of genes involved in neurogenesis and development. We describe an autosomal dominant disorder associated with de novo missense variants in the degron of AFF3, a nine amino acid sequence important for its binding to ubiquitin ligase, or with de novo deletions of this region. The sixteen affected individuals we identified, along with two previously reported individuals, present with a recognizable pattern of anomalies, which we named KINSSHIP syndrome (KI for horseshoe kidney, NS for Nievergelt/Savarirayan type of mesomelic dysplasia, S for seizures, H for hypertrichosis, I for intellectual disability, and P for pulmonary involvement), partially overlapping the AFF4-associated CHOPS syndrome. Whereas homozygous Aff3 knockout mice display skeletal anomalies, kidney defects, brain malformations, and neurological anomalies, knockin animals modeling one of the microdeletions and the most common of the missense variants identified in affected individuals presented with lower mesomelic limb deformities like KINSSHIP-affected individuals and early lethality, respectively. Overexpression of AFF3 in zebrafish resulted in body axis anomalies, providing some support for the pathological effect of increased amount of AFF3. The only partial phenotypic overlap of AFF3- and AFF4-associated syndromes and the previously published transcriptome analyses of ALF transcription factors suggest that these factors are not redundant and each contributes uniquely to proper development.


Asunto(s)
Encefalopatías/genética , Epilepsia/genética , Riñón Fusionado/genética , Discapacidad Intelectual/genética , Mutación Missense , Proteínas Nucleares/genética , Osteocondrodisplasias/genética , Adolescente , Secuencia de Aminoácidos , Animales , Encefalopatías/etiología , Niño , Preescolar , Epilepsia/complicaciones , Evolución Molecular , Femenino , Frecuencia de los Genes , Humanos , Lactante , Masculino , Ratones , Modelos Moleculares , Proteínas Nucleares/química , Proteínas Nucleares/deficiencia , Fenotipo , Estabilidad Proteica , Síndrome , Factores de Elongación Transcripcional/química , Factores de Elongación Transcripcional/genética , Adulto Joven , Pez Cebra/genética
2.
J Surg Res ; 300: 402-408, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38848640

RESUMEN

INTRODUCTION: We sought to explore the relationship between various surgeon-related and hospital-level characteristics and clinical outcomes among patients requiring cardiac surgery. METHODS: We searched the New York State Cardiac Data Reporting System for all coronary artery bypass grafting (CABG) and valve cases between 2015 and 2017. The data were analyzed without dichotomization. RESULTS: Among CABG/valve surgeons, case volume was positively correlated with years in practice (P = 0.002) and negatively correlated with risk-adjusted mortality ratio (P = 0.014). For CABG and CABG/valve surgeons, our results showed a negative association between teaching status and case volume (P = 0.002, P = 0.018). Among CABG surgeons, hospital teaching status and presence of cardiothoracic surgery residency were inversely associated with risk-adjusted mortality ratio (P = 0.006, P = 0.029). CONCLUSIONS: There is a complex relationship between case volume, teaching status, and surgical outcomes suggesting that balance between academics and volume is needed.

3.
Pharmacol Res ; 191: 106759, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37023990

RESUMEN

Considerable progress has been made in recent years towards the identification and characterisation of novel subtype-selective modulators of nicotinic acetylcholine receptors (nAChRs). In particular, this has focussed on modulators of α7 nAChRs, a nAChR subtype that has been identified as a target for drug discovery in connection with a range of potential therapeutic applications. This review focusses upon α7-selective modulators that bind to receptor sites other than the extracellular 'orthosteric' agonist binding site for the endogenous agonist acetylcholine (ACh). Such compounds include those that are able to potentiate responses evoked by orthosteric agonists such as ACh (positive allosteric modulators; PAMs) and those that are able to activate α7 nAChRs by direct allosteric activation in the absence of an orthosteric agonist (allosteric agonists or 'ago-PAMs'). There has been considerable debate about the mechanism of action of α7-selective PAMs and allosteric agonists, much of which has centred around identifying the location of their binding sites on α7 nAChRs. Based on a variety of experimental evidence, including recent structural data, there is now clear evidence indicating that at least some α7-selective PAMs bind to an inter-subunit site located in the transmembrane domain. In contrast, there are differing hypotheses about the site or sites at which allosteric agonists bind to α7 nAChRs. It will be argued that the available evidence supports the conclusion that direct allosteric activation by allosteric agonists/ago-PAMs occurs via the same inter-subunit transmembrane site that has been identified for several α7-selective PAMs.


Asunto(s)
Receptores Nicotínicos , Receptor Nicotínico de Acetilcolina alfa 7 , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Regulación Alostérica , Sitios de Unión , Receptores Nicotínicos/metabolismo , Acetilcolina/farmacología
4.
Pediatr Dermatol ; 38 Suppl 2: 137-139, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34585435

RESUMEN

In the dermatologic medical literature, there is an underrepresentation of conditions in individuals of color. Due to the lack of representation, it may be harder for clinicians to recognize certain diagnoses in patients with darker skin phototypes leading to misdiagnosis and affecting overall patient management, outcomes, and satisfaction. Here, we present four Black or Indigenous People of Color who were initially referred for hyperpigmentation, hemihyperplasia, or café au lait spots and found to have syndromic capillary malformations.


Asunto(s)
Malformaciones Arteriovenosas , Hiperpigmentación , Mancha Vino de Oporto , Malformaciones Vasculares , Capilares/anomalías , Errores Diagnósticos , Humanos , Mancha Vino de Oporto/diagnóstico , Malformaciones Vasculares/diagnóstico , Proteína Activadora de GTPasa p120
5.
Genet Med ; 22(7): 1215-1226, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32376980

RESUMEN

PURPOSE: Somatic variants in tumor necrosis factor receptor-associated factor 7 (TRAF7) cause meningioma, while germline variants have recently been identified in seven patients with developmental delay and cardiac, facial, and digital anomalies. We aimed to define the clinical and mutational spectrum associated with TRAF7 germline variants in a large series of patients, and to determine the molecular effects of the variants through transcriptomic analysis of patient fibroblasts. METHODS: We performed exome, targeted capture, and Sanger sequencing of patients with undiagnosed developmental disorders, in multiple independent diagnostic or research centers. Phenotypic and mutational comparisons were facilitated through data exchange platforms. Whole-transcriptome sequencing was performed on RNA from patient- and control-derived fibroblasts. RESULTS: We identified heterozygous missense variants in TRAF7 as the cause of a developmental delay-malformation syndrome in 45 patients. Major features include a recognizable facial gestalt (characterized in particular by blepharophimosis), short neck, pectus carinatum, digital deviations, and patent ductus arteriosus. Almost all variants occur in the WD40 repeats and most are recurrent. Several differentially expressed genes were identified in patient fibroblasts. CONCLUSION: We provide the first large-scale analysis of the clinical and mutational spectrum associated with the TRAF7 developmental syndrome, and we shed light on its molecular etiology through transcriptome studies.


Asunto(s)
Discapacidad Intelectual , Transcriptoma , Exoma , Células Germinativas , Humanos , Discapacidad Intelectual/genética , Mutación Missense , Fenotipo , Transcriptoma/genética , Péptidos y Proteínas Asociados a Receptores de Factores de Necrosis Tumoral
6.
Am J Med Genet A ; 182(6): 1460-1465, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32267060

RESUMEN

Congenital disorders of glycosylation (CDG) are metabolic disorders that affect the glycosylation of proteins and lipids. Since glycosylation affects all organs, CDG show a wide spectrum of phenotypes. We present a patient with microcephaly, dysmorphic facies, congenital heart defect, focal epilepsy, infantile spasms, skeletal dysplasia, and a type 1 serum transferrin isoelectrofocusing due to a novel CDG caused by a homozygous variant in the oligosaccharyltransferase complex noncatalytic subunit (OSTC) gene involved in glycosylation and confirmed by serum transferrin electrophoresis.


Asunto(s)
Trastornos Congénitos de Glicosilación/genética , Epilepsia/genética , Hexosiltransferasas/genética , Proteínas de la Membrana/genética , Trastornos Congénitos de Glicosilación/complicaciones , Trastornos Congénitos de Glicosilación/patología , Epilepsia/complicaciones , Epilepsia/patología , Femenino , Humanos , Lactante , Masculino , Mutación/genética , Fenotipo , Transferrina/genética , Secuenciación del Exoma
7.
Genet Med ; 21(2): 459-463, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29872110

RESUMEN

PURPOSE: To examine results of magnetic resonance imaging (MRI), polysomnograms (PSG), and patient outcomes in patients with achondroplasia in light of recent screening recommendations for infants with achondroplasia. METHODS: We reviewed medical records of 49 patients with achondroplasia followed at our institution between September 1997 and January 2017, including physical exams, MRIs, PSGs (when available), and surgical histories. Appropriate PSG data were available for 39 of these patients. RESULTS: Twenty-seven of 49 patients had cervical cord compression on MRI, and 20 of those patients required surgery. Central apnea was detected in 2/23 patients with cervical cord compression in whom PSG data was available. Physical exam revealed depressed deep-tendon reflexes in two patients with cord compression and one patient without cord compression. Besides hypotonia in some, the neurological exams of these patients were unremarkable. CONCLUSIONS: Cervical cord compression is a common occurrence in infants with achondroplasia and necessitates surgical intervention in some patients. Physical exam and PSG are poor predictors of the presence of cord compression or the need for surgery. All infants with achondroplasia should have MRIs of the craniocervical junction in the first 6 months of life.


Asunto(s)
Acondroplasia/complicaciones , Pruebas Diagnósticas de Rutina , Neuroimagen , Compresión de la Médula Espinal/etiología , Acondroplasia/diagnóstico , Femenino , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Registros Médicos , Compresión de la Médula Espinal/diagnóstico
8.
Hum Genet ; 137(5): 375-388, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29740699

RESUMEN

Many genetic causes of developmental delay and/or intellectual disability (DD/ID) are extremely rare, and robust discovery of these requires both large-scale DNA sequencing and data sharing. Here we describe a GeneMatcher collaboration which led to a cohort of 13 affected individuals harboring protein-altering variants, 11 of which are de novo, in MED13; the only inherited variant was transmitted to an affected child from an affected mother. All patients had intellectual disability and/or developmental delays, including speech delays or disorders. Other features that were reported in two or more patients include autism spectrum disorder, attention deficit hyperactivity disorder, optic nerve abnormalities, Duane anomaly, hypotonia, mild congenital heart abnormalities, and dysmorphisms. Six affected individuals had mutations that are predicted to truncate the MED13 protein, six had missense mutations, and one had an in-frame-deletion of one amino acid. Out of the seven non-truncating mutations, six clustered in two specific locations of the MED13 protein: an N-terminal and C-terminal region. The four N-terminal clustering mutations affect two adjacent amino acids that are known to be involved in MED13 ubiquitination and degradation, p.Thr326 and p.Pro327. MED13 is a component of the CDK8-kinase module that can reversibly bind Mediator, a multi-protein complex that is required for Polymerase II transcription initiation. Mutations in several other genes encoding subunits of Mediator have been previously shown to associate with DD/ID, including MED13L, a paralog of MED13. Thus, our findings add MED13 to the group of CDK8-kinase module-associated disease genes.


Asunto(s)
Secuencia de Aminoácidos , Complejo Mediador/genética , Mutación Missense , Trastornos del Neurodesarrollo/genética , Eliminación de Secuencia , Adulto , Niño , Preescolar , Quinasa 8 Dependiente de Ciclina/genética , Quinasa 8 Dependiente de Ciclina/metabolismo , Femenino , Humanos , Masculino , Complejo Mediador/metabolismo , Trastornos del Neurodesarrollo/metabolismo , Iniciación de la Transcripción Genética , Ubiquitinación/genética , Reino Unido
9.
Int Ophthalmol ; 38(6): 2677-2682, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29058245

RESUMEN

PURPOSE: To report a case of OFCD associated with a de novo BCOR pathogenic variant and highlight the ocular findings and possible mechanisms. METHODS: A retrospective chart review of the patient's ocular and systemic findings was performed. The patient underwent diagnostic whole exome sequencing (WES). RESULTS: The patient had a comprehensive eye exam in infancy demonstrating bilateral congenital cataracts consisting of posterior lenticonus with a posterior cortical opacity. She also had blepharoptosis with a hooded appearance and retinal pigment hypertrophy of the inferior retina bilaterally. Systemic findings include atrial septal defect, patent ductus arteriosus, congenital clubfoot, syndactyly, tethered cord, and laryngeal cleft. WES identified a de novo heterozygous R1136X pathogenic variant in the BCOR gene. CONCLUSION: The typical ocular manifestation of OFCD syndrome is congenital cataracts, which can have a significant impact on visual development and so should be considered in patients with multiple medical issues that may fit the diagnosis. A comprehensive eye exam in these patients is thus warranted.


Asunto(s)
Catarata/congénito , Catarata/etiología , Anomalías del Ojo/etiología , Defectos de los Tabiques Cardíacos/complicaciones , Microftalmía/complicaciones , Proteínas Proto-Oncogénicas/genética , Proteínas Represoras/genética , Blefaroptosis/etiología , Catarata/complicaciones , Catarata/genética , Femenino , Defectos de los Tabiques Cardíacos/genética , Humanos , Lactante , Microftalmía/genética , Estudios Retrospectivos
10.
Neurogenetics ; 17(3): 173-8, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27094857

RESUMEN

Exome sequencing is an effective way to identify genetic causes of etiologically heterogeneous conditions such as developmental delay and intellectual disabilities. Using exome sequencing, we have identified four patients with similar phenotypes of developmental delay, intellectual disability, failure to thrive, hypotonia, ataxia, and tooth enamel defects who all have the same de novo R331W missense variant in C-terminal binding protein 1 (CTBP1). CTBP1 is a transcriptional regulator critical for development by coordinating different regulatory pathways. The R331W variant found in these patients is within the C-terminal portion of the PLDLS (Pro-Leu-Asp-Leu-Ser) binding cleft, which is the domain through which CTBP1, interacts with chromatin-modifying enzymes and mediates chromatin-dependent gene repression pathways. This is the first report of mutations within CTBP1 in association with any human disease.


Asunto(s)
Oxidorreductasas de Alcohol/genética , Ataxia/genética , Proteínas de Unión al ADN/genética , Esmalte Dental/patología , Discapacidades del Desarrollo/genética , Hipotonía Muscular/genética , Mutación Missense , Adulto , Ataxia/complicaciones , Niño , Discapacidades del Desarrollo/complicaciones , Femenino , Humanos , Discapacidad Intelectual/complicaciones , Discapacidad Intelectual/genética , Masculino , Hipotonía Muscular/complicaciones , Secuenciación del Exoma , Adulto Joven
11.
J Endocr Soc ; 8(7): bvae101, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38859884

RESUMEN

Context: Kabuki syndrome (KS) is associated with congenital hyperinsulinism (HI). Objective: To characterize the clinical and molecular features of HI in children with KS. Design: Retrospective cohort study of children with KS and HI evaluated between 1998 and 2023. Setting: The Congenital Hyperinsulinism Center of the Children's Hospital of Philadelphia. Patients: Thirty-three children with KS and HI. Main Outcome Measures: HI presentation, treatment, course, and genotype. Results: Hypoglycemia was recognized on the first day of life in 25 children (76%). Median age at HI diagnosis was 1.8 months (interquartile range [IQR], 0.6-6.1 months). Median age at KS diagnosis was 5 months (IQR, 2-14 months). Diagnosis of HI preceded KS diagnosis in 20 children (61%). Twenty-four children (73%) had a pathogenic variant in KMT2D, 5 children (15%) had a pathogenic variant in KDM6A, and 4 children (12%) had a clinical diagnosis of KS. Diazoxide trial was conducted in 25 children, 92% of whom were responsive. HI treatment was discontinued in 46% of the cohort at median age 2.8 years (IQR, 1.3-5.7 years). Conclusion: Hypoglycemia was recognized at birth in most children with KS and HI, but HI diagnosis was often delayed. HI was effectively managed with diazoxide in most children. In contrast to prior reports, the frequency of variants in KMT2D and KDM6A were similar to their overall prevalence in individuals with KS. Children diagnosed with KS should undergo evaluation for HI, and, because KS features may not be recognized in infancy, KMT2D and KDM6A should be included in the genetic evaluation of HI.

12.
ACS Bio Med Chem Au ; 3(2): 147-157, 2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37096031

RESUMEN

Methyllycaconitine (MLA), 1, is a naturally occurring norditerpenoid alkaloid that is a highly potent (IC50 = 2 nM) selective antagonist of α7 nicotinic acetylcholine receptors (nAChRs). Several structural factors affect its activity such as the neopentyl ester side-chain and the piperidine ring N-side-chain. The synthesis of simplified AE-bicyclic analogues 14-21 possessing different ester and nitrogen side-chains was achieved in three steps. The antagonist effects of synthetic analogues were examined on human α7 nAChRs and compared to that of MLA 1. The most efficacious analogue (16) reduced α7 nAChR agonist responses [1 nM acetylcholine (ACh)] to 53.2 ± 1.9% compared to 3.4 ± 0.2% for MLA 1. This demonstrates that simpler analogues of MLA 1 possess antagonist effects on human α7 nAChRs but also indicates that further optimization may be possible to achieve antagonist activity comparable to that of MLA 1.

13.
JCI Insight ; 8(9)2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-37154160

RESUMEN

Central conducting lymphatic anomaly (CCLA) due to congenital maldevelopment of the lymphatics can result in debilitating and life-threatening disease with limited treatment options. We identified 4 individuals with CCLA, lymphedema, and microcystic lymphatic malformation due to pathogenic, mosaic variants in KRAS. To determine the functional impact of these variants and identify a targeted therapy for these individuals, we used primary human dermal lymphatic endothelial cells (HDLECs) and zebrafish larvae to model the lymphatic dysplasia. Expression of the p.Gly12Asp and p.Gly13Asp variants in HDLECs in a 2­dimensional (2D) model and 3D organoid model led to increased ERK phosphorylation, demonstrating these variants activate the RAS/MAPK pathway. Expression of activating KRAS variants in the venous and lymphatic endothelium in zebrafish resulted in lymphatic dysplasia and edema similar to the individuals in the study. Treatment with MEK inhibition significantly reduced the phenotypes in both the organoid and the zebrafish model systems. In conclusion, we present the molecular characterization of the observed lymphatic anomalies due to pathogenic, somatic, activating KRAS variants in humans. Our preclinical studies suggest that MEK inhibition should be studied in future clinical trials for CCLA due to activating KRAS pathogenic variants.


Asunto(s)
Proteínas Proto-Oncogénicas p21(ras) , Pez Cebra , Animales , Humanos , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Células Endoteliales/metabolismo , Fosforilación , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
14.
ACS Chem Neurosci ; 13(12): 1805-1817, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35657695

RESUMEN

Quinolone antibiotics disrupt bacterial DNA synthesis by interacting with DNA gyrase and topoisomerase IV. However, in addition, they have been shown to act as inhibitors of pentameric ligand-gated ion channels such as GABAA receptors and the α7 nicotinic acetylcholine receptor (nAChR). In the present study, we have examined the effects of quinolone antibiotics on the human α4ß2 nAChR, an important subtype that is widely expressed in the central nervous system. A key feature of α4ß2 nAChRs is their ability to coassemble into two distinct stoichiometries, (α4)2(ß2)3 and (α4)3(ß2)2, which results in differing affinities for acetylcholine. The effects of nine quinolone antibiotics were examined on both stoichiometries of the α4ß2 receptor by two-electrode voltage-clamp recording. All compounds exhibited significant inhibition of α4ß2 nAChRs. However, all of the fluoroquinolone antibiotics examined (ciprofloxacin, enoxacin, enrofloxacin, difloxacin, norfloxacin, pefloxacin, and sparfloxacin) were significantly more potent inhibitors of (α4)2(ß2)3 nAChRs than of (α4)3(ß2)2 nAChRs. This stoichiometry-selective effect was most pronounced with pefloxacin, which inhibited (α4)2(ß2)3 nAChRs with an IC50 of 26.4 ± 3.4 µM but displayed no significant inhibition of (α4)3(ß2)2 nAChRs. In contrast, two nonfluorinated quinolone antibiotics (cinoxacin and oxolinic acid) exhibited no selectivity in their inhibition of the two stoichiometries of α4ß2. Computational docking studies suggest that pefloxacin interacts selectively with an allosteric transmembrane site at the ß2(+)/ß2(-) subunit interface, which is consistent with its selective inhibition of (α4)2(ß2)3. These findings concerning the antagonist effects of fluoroquinolones provide further evidence that differences in the subunit stoichiometry of heteromeric nAChRs can result in substantial differences in pharmacological properties.


Asunto(s)
Antibacterianos , Fluoroquinolonas , Antagonistas Nicotínicos , Pefloxacina , Receptores Nicotínicos , Antibacterianos/farmacología , Fluoroquinolonas/farmacología , Humanos , Antagonistas Nicotínicos/farmacología , Oocitos , Pefloxacina/farmacología , Receptores Nicotínicos/metabolismo
15.
PLoS One ; 16(7): e0254251, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34234379

RESUMEN

Pentameric ligand-gated ion channels (pLGICs) activated by the inhibitory neurotransmitter γ-aminobutyric acid (GABA) are expressed widely in both vertebrate and invertebrate species. One of the best characterised insect GABA-gated chloride channels is RDL, an abbreviation of 'resistance to dieldrin', that was originally identified by genetic screening in Drosophila melanogaster. Here we have cloned the analogous gene from the bumblebee Bombus terrestris audax (BtRDL) and examined its pharmacological properties by functional expression in Xenopus oocytes. Somewhat unexpectedly, the sensitivity of BtRDL to GABA, as measured by its apparent affinity (EC50), was influenced by heterologous expression conditions. This phenomenon was observed in response to alterations in the amount of cRNA injected; the length of time that oocytes were incubated before functional analysis; and by the presence or absence of a 3' untranslated region. In contrast, similar changes in expression conditions were not associated with changes in apparent affinity with RDL cloned from D. melanogaster (DmRDL). Changes in apparent affinity with BtRDL were also observed following co-expression of a chaperone protein (NACHO). Similar changes in apparent affinity were observed with an allosteric agonist (propofol) and a non-competitive antagonist (picrotoxinin), indicating that expression-depended changes are not restricted to the orthosteric agonist binding site. Interestingly, instances of expression-dependent changes in apparent affinity have been reported previously for vertebrate glycine receptors, which are also members of the pLGIC super-family. Our observations with BtRDL are consistent with previous data obtained with vertebrate glycine receptors and indicates that agonist and antagonist apparent affinity can be influenced by the level of functional expression in a variety of pLGICs.


Asunto(s)
Canales de Cloruro/antagonistas & inhibidores , Canales de Cloruro/metabolismo , Drosophila melanogaster/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Regiones no Traducidas 3'/efectos de los fármacos , Secuencia de Aminoácidos , Animales , Abejas/metabolismo , Agonistas de los Canales de Cloruro/farmacología , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/efectos de los fármacos , Femenino , Picrotoxina/análogos & derivados , Picrotoxina/farmacología , Propofol/farmacología , Receptores de Glicina/metabolismo , Sesterterpenos , Xenopus laevis/metabolismo
16.
Artículo en Inglés | MEDLINE | ID: mdl-33608380

RESUMEN

Transcriptional analysis can be utilized to reconcile variants of uncertain significance, particularly those predicted to impact splicing. Laboratory analysis of the predicted mRNA transcript may allow inference of the in vivo impact of the variant and aid prediction of its clinical significance. We present a patient with classical features of primary ciliary dyskinesia (PCD) who was identified to have compound heterozygous variants in the DNAH11 gene (c.10691 + 2T > C, c.13523_13543dup21) via trio whole-exome sequencing in 2013. These variants were originally classified as Mutation and Likely Mutation. However, these variants were downgraded to variants of uncertain significance (VUSs) during reanalysis in 2016 because of uncertainty that they caused a loss of function of the gene. c.10691 + 2T > C is predicted to abrogate the canonical splice site and lead to the skipping of exon 65, but the adjoining of exon 64 and exon 66 in the DNAH11 transcript preserves the reading frame of the resultant protein. c.13523_13543dup21 is located in the last exon of the DNAH11 coding sequence, upstream of the canonical stop codon, which suggests a reduced likelihood to trigger nonsense-mediated decay (NMD). Transcriptional analysis was performed to characterize the impact of the variants, resulting in reclassification of c.10691 + 2T > C to Likely Pathogenic by providing evidence that it results in a deleterious effect and subsequent downstream reclassification of c.13523_13543dup21 to Likely Pathogenic as well. Our case illustrates the potential impact of transcriptional analysis on variant resolution, supporting its usage on variants that exert an unpredictable effect on splicing.


Asunto(s)
Dineínas Axonemales/genética , Trastornos de la Motilidad Ciliar/genética , Trastornos de la Motilidad Ciliar/metabolismo , Transcriptoma , Preescolar , Trastornos de la Motilidad Ciliar/clasificación , Trastornos de la Motilidad Ciliar/patología , Exones , Femenino , Perfilación de la Expresión Génica , Humanos , Mutación , Linaje , Empalme del ARN , ARN Mensajero/metabolismo
17.
Artículo en Inglés | MEDLINE | ID: mdl-34887309

RESUMEN

Disorganized morphogenesis of arteries, veins, capillaries, and lymphatic vessels results in vascular malformations. Most individuals with isolated vascular malformations have postzygotic (mosaic), activating pathogenic variants in a handful of oncogenes within the PI3K-RAS-MAPK pathway (Padia et al., Laryngoscope Investig Otolaryngol 4: 170-173 [2019]). Activating pathogenic variants in the gene PIK3CA, which encodes for the catalytic subunit of phosphatidylinositol 3-kinase, are present in both lymphatic and venous malformations as well as arteriovenous malformations in other complex disorders such as CLOVES syndrome (congenital, lipomatous, overgrowth, vascular malformations, epidermal anevi, scoliosis) (Luks et al., Pediatr Dev Pathol 16: 51 [2013]; Luks et al., J Pediatr 166: 1048-1054.e1-5 [2015]; Al-Olabi et al., J Clin Invest 128: 1496-1508 [2018]). These vascular malformations are part of the PIK3CA-related overgrowth spectrum, a spectrum of entities that have regionalized disordered growth due to the presence of tissue-restricted postzygotic PIK3CA pathogenic variants (Keppler-Noreuil et al., Am J Med Genet A 167A: 287-295 [2015]). Cerebrofacial vascular metameric syndrome (CVMS; also described as cerebrofacial arteriovenous metameric syndrome, Bonnet-Dechaume-Blanc syndrome, and Wyburn-Mason syndrome) is the association of retinal, facial, and cerebral vascular malformations (Bhattacharya et al., Interv Neuroradiol 7: 5-17 [2001]; Krings et al., Neuroimaging Clin N Am 17: 245-258 [2007]). The segmental distribution, the presence of tissue overgrowth, and the absence of familial recurrence are all consistent with CVMS being caused by a postzygotic mutation, which has been hypothesized by previous authors (Brinjiki et al., Am J Neuroradiol 39: 2103-2107 [2018]). However, the genetic cause of CVMS has not yet been described. Here, we present three individuals with CVMS and mosaic activating pathogenic variants within the gene PIK3CA We propose that CVMS be recognized as part of the PIK3CA-related overgrowth spectrum, providing justification for future trials using pharmacologic PIK3CA inhibitors (e.g., alpelisib) for these difficult-to-treat patients.


Asunto(s)
Anomalías Musculoesqueléticas , Malformaciones Vasculares , Fosfatidilinositol 3-Quinasa Clase I/genética , Humanos , Anomalías Musculoesqueléticas/genética , Mutación , Oncogenes , Fosfatidilinositol 3-Quinasas/genética , Malformaciones Vasculares/genética
18.
Eur J Hum Genet ; 27(5): 738-746, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30679813

RESUMEN

Determining pathogenicity of genomic variation identified by next-generation sequencing techniques can be supported by recurrent disruptive variants in the same gene in phenotypically similar individuals. However, interpretation of novel variants in a specific gene in individuals with mild-moderate intellectual disability (ID) without recognizable syndromic features can be challenging and reverse phenotyping is often required. We describe 24 individuals with a de novo disease-causing variant in, or partial deletion of, the F-box only protein 11 gene (FBXO11, also known as VIT1 and PRMT9). FBXO11 is part of the SCF (SKP1-cullin-F-box) complex, a multi-protein E3 ubiquitin-ligase complex catalyzing the ubiquitination of proteins destined for proteasomal degradation. Twenty-two variants were identified by next-generation sequencing, comprising 2 in-frame deletions, 11 missense variants, 1 canonical splice site variant, and 8 nonsense or frameshift variants leading to a truncated protein or degraded transcript. The remaining two variants were identified by array-comparative genomic hybridization and consisted of a partial deletion of FBXO11. All individuals had borderline to severe ID and behavioral problems (autism spectrum disorder, attention-deficit/hyperactivity disorder, anxiety, aggression) were observed in most of them. The most relevant common facial features included a thin upper lip and a broad prominent space between the paramedian peaks of the upper lip. Other features were hypotonia and hyperlaxity of the joints. We show that de novo variants in FBXO11 cause a syndromic form of ID. The current series show the power of reverse phenotyping in the interpretation of novel genetic variances in individuals who initially did not appear to have a clear recognizable phenotype.


Asunto(s)
Anomalías Múltiples/genética , Conducta , Proteínas F-Box/genética , Variación Genética , Discapacidad Intelectual/genética , Proteína-Arginina N-Metiltransferasas/genética , Eliminación de Gen , Humanos , Síndrome
19.
Neuropharmacology ; 139: 194-204, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30009834

RESUMEN

Several previous studies have demonstrated that the activity of neurotransmitters acting on ligand-gated ion channels such as the nicotinic acetylcholine receptor (nAChR) can be altered by compounds binding to allosteric modulatory sites. In the case of α7 nAChRs, both positive and negative allosteric modulators (PAMs and NAMs) have been identified and have attracted considerable interest. A recent study, employing revised structural models of the transmembrane domain of the α7 nAChR in closed and open conformations, has provided support for an inter-subunit transmembrane allosteric binding site (Newcombe et al 2017). In the present study, we have performed virtual screening of the DrugBank database using pharmacophore queries that were based on the predicted binding mode of PAMs to α7 nAChR structural models. A total of 81 compounds were identified in the DrugBank database, of which the 25 highest-ranked hits corresponded to one of four previously-identified therapeutic compound groups (carbonic anhydrase inhibitors, cyclin-dependent kinase inhibitors, diuretics targeting the Na+-K+-Cl- cotransporter, and fluoroquinolone antibiotics targeting DNA gyrase). The top-ranked compound from each of these four groups (DB04763, DB08122, furosemide and pefloxacin, respectively) was tested for its effects on human α7 nAChR expressed in Xenopus oocytes using two-electrode voltage-clamp electrophysiology. These studies, conducted with wild-type, mutant and chimeric receptors, resulted in all four compounds exerting allosteric modulatory effects. While DB04763, DB08122 and pefloxacin were antagonists, furosemide potentiated ACh responses. Our findings, supported by docking studies, are consistent with these compounds acting as PAMs and NAMs of the α7 nAChR via interaction with a transmembrane site.


Asunto(s)
Agonistas Nicotínicos/farmacología , Antagonistas Nicotínicos/farmacología , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Receptor Nicotínico de Acetilcolina alfa 7/antagonistas & inhibidores , Regulación Alostérica , Sitio Alostérico , Animales , Evaluación Preclínica de Medicamentos/métodos , Furosemida/química , Furosemida/farmacología , Humanos , Potenciales de la Membrana/efectos de los fármacos , Simulación del Acoplamiento Molecular , Estructura Molecular , Mutagénesis Sitio-Dirigida , Agonistas Nicotínicos/química , Antagonistas Nicotínicos/química , Oocitos , Pefloxacina/química , Pefloxacina/farmacología , Conformación Proteica , Xenopus laevis , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
20.
Resuscitation ; 92: 19-25, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25906941

RESUMEN

BACKGROUND: It is unknown whether targeted temperature management (TTM) improves survival after pediatric out-of-hospital cardiac arrest (OHCA). The aim of this study was to assess the evolution, safety and efficacy of TTM (32-34 °C) compared to standard temperature management (STM) (<38 °C). METHODS: Retrospective, single center cohort study. Patients aged >one day up to 16 years, admitted to a UK Paediatric Intensive Care Unit (PICU) after OHCA (January 2004-December 2010). Primary outcome was survival to hospital discharge; efficacy and safety outcomes included: application of TTM, physiological, hematological and biochemical side effects. RESULTS: Seventy-three patients were included. Thirty-eight patients (52%) received TTM (32-34 °C). Prior to ILCOR guidance adoption in January 2007, TTM was used infrequently (4/25; 16%). Following adoption, TTM (32-34 °C) use increased significantly (34/48; 71% Chi(2); p < 0.0001). TTM (32-34 °C) and STM (<38 °C) groups were similar at baseline. TTM (32-34 °C) was associated with bradycardia and hypotension compared to STM (<38 °C). TTM (32-34 °C) reduced episodes of hyperthermia (>38 °C) in the 1st 24h; however, excessive hypothermia (<32 °C) and hyperthermia (>38 °C) occurred in both groups up to 72 h, and all patients (n = 11) experiencing temperature <32 °C died. The study was underpowered to determine a difference in hospital survival (34% (TTM (32-34 °C)) versus 23% (STM (<38 °C)); p = 0.284). However, the TTM (32-34 °C) group had a significantly longer PICU length of stay. CONCLUSIONS: TTM (32-34 °C) was feasible but associated with bradycardia, hypotension, and increased length of stay in PICU. Temperature <32 °C had a universally grave prognosis. Larger studies are required to assess effect on survival.


Asunto(s)
Reanimación Cardiopulmonar/métodos , Hipertermia Inducida/métodos , Hipotermia Inducida/métodos , Paro Cardíaco Extrahospitalario/terapia , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Paro Cardíaco Extrahospitalario/mortalidad , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Temperatura , Resultado del Tratamiento , Reino Unido/epidemiología
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