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1.
Proc Natl Acad Sci U S A ; 120(49): e2315096120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38011564

RESUMO

Hidradenitis suppurativa (HS) is a complex inflammatory skin disease with undefined mechanistic underpinnings. Here, we investigated HS epithelial cells and demonstrated that HS basal progenitors modulate their lineage restriction and give rise to pathogenic keratinocyte clones, resulting in epidermal hyperproliferation and dysregulated inflammation in HS. When comparing to healthy epithelial stem/progenitor cells, in HS, we identified changes in gene signatures that revolve around the mitotic cell cycle, DNA damage response and repair, as well as cell-cell adhesion and chromatin remodeling. By reconstructing cell differentiation trajectory and CellChat modeling, we identified a keratinocyte population specific to HS. This population is marked by S100A7/8/9 and KRT6 family members, triggering IL1, IL10, and complement inflammatory cascades. These signals, along with HS-specific proinflammatory cytokines and chemokines, contribute to the recruitment of certain immune cells during the disease progression. Furthermore, we revealed a previously uncharacterized role of S100A8 in regulating the local chromatin environment of target loci in HS keratinocytes. Through the integration of genomic and epigenomic datasets, we identified genome-wide chromatin rewiring alongside the switch of transcription factors (TFs), which mediated HS transcriptional profiles. Importantly, we identified numerous clinically relevant inflammatory enhancers and their coordinated TFs in HS basal CD49fhigh cells. The disruption of the S100A enhancer using the CRISPR/Cas9-mediated approach or the pharmacological inhibition of the interferon regulatory transcription factor 3 (IRF3) efficiently reduced the production of HS-associated inflammatory regulators. Our study not only uncovers the plasticity of epidermal progenitor cells in HS but also elucidates the epigenetic mechanisms underlying HS pathogenesis.


Assuntos
Hidradenite Supurativa , Humanos , Hidradenite Supurativa/genética , Pele/metabolismo , Epigenômica , Epigênese Genética , Células-Tronco/metabolismo , Cromatina/metabolismo
2.
Genet Med ; 26(1): 101010, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37860969

RESUMO

PURPOSE: Multiple studies suggest an association between DLG2 and neurodevelopmental disorders and indicate the haploinsufficiency of this gene; however, few cases have been thoroughly described. We performed additional studies to confirm this clinical association and DLG2 haploinsufficiency. METHODS: Chromosomal microarray analysis was performed on 11,107 patients at the Cytogenetics Laboratory at the University of Alabama at Birmingham. The Database of Genomic Variants-Gold Standard Variants and the Genome Aggregation Database were selected for the association analysis. Fifty-nine patients from the literature and DECIPHER, all having DLG2 intragenic deletions, were included for comprehensive analysis of the distribution of these deletions. RESULTS: A total of 13 patients with DLG2 intragenic deletions, from 10 families in our cohort, were identified. Nine of 10 probands presented with clinical features of neurodevelopmental disorders. Congenital anomalies and dysmorphism were common in our cohort of patients. Association analysis showed that the frequency of DLG2 deletions in our cohort is significantly higher than those in the Database of Genomic Variants-Gold Standard Variants and the Genome Aggregation Database. Most of DLG2 intragenic deletions identified in 69 unrelated patients from our cohort, the literature, and DECIPHER map to the 5' region of the gene, with a hotspot centered around HPin7, exon 8, and HPin8. CONCLUSION: Our findings reinforce the link between DLG2 intragenic deletions and neurodevelopmental disorders, strongly support the haploinsufficiency of this gene, and indicate that these deletions might also have an association with congenital anomalies and dysmorphism.


Assuntos
Transtornos do Neurodesenvolvimento , Humanos , Transtornos do Neurodesenvolvimento/genética , Éxons/genética , Haploinsuficiência/genética , Proteínas Supressoras de Tumor/genética , Guanilato Quinases/genética
3.
Mol Psychiatry ; 28(2): 588-600, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36357671

RESUMO

Posttraumatic stress disorder (PTSD) after the pandemic has emerged as a major neuropsychiatric component of post-acute COVID-19 syndrome, yet the current pharmacotherapy for PTSD is limited. The use of adrenergic drugs to treat PTSD has been suggested; however, it is hindered by conflicting clinical results and a lack of mechanistic understanding of drug actions. Our studies, using both genetically modified mice and human induced pluripotent stem cell-derived neurons, reveal a novel α2A adrenergic receptor (α2AAR)-spinophilin-cofilin axis in the hippocampus that is critical for regulation of contextual fear memory reconsolidation. In addition, we have found that two α2 ligands, clonidine and guanfacine, exhibit differential abilities in activating this signaling axis to disrupt fear memory reconsolidation. Stimulation of α2AAR with clonidine, but not guanfacine, promotes the interaction of the actin binding protein cofilin with the receptor and with the dendritic spine scaffolding protein spinophilin to induce cofilin activation at the synapse. Spinophilin-dependent regulation of cofilin is required for clonidine-induced disruption of contextual fear memory reconsolidation. Our results inform the interpretation of differential clinical observations of these two drugs on PTSD and suggest that clonidine could provide immediate treatment for PTSD symptoms related to the current pandemic. Furthermore, our study indicates that modulation of dendritic spine morphology may represent an effective strategy for the development of new pharmacotherapies for PTSD.


Assuntos
COVID-19 , Células-Tronco Pluripotentes Induzidas , Animais , Humanos , Camundongos , Fatores de Despolimerização de Actina/farmacologia , Adrenérgicos/farmacologia , Clonidina/farmacologia , Medo/fisiologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas dos Microfilamentos/metabolismo , Receptores Adrenérgicos alfa 2/metabolismo
4.
Hum Genet ; 142(7): 849-861, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37186028

RESUMO

Neurofibromatosis type 1 results from loss-of-function NF1 pathogenic variants (PVs). Up to 30% of all NF1 PVs disrupt mRNA splicing, including deep intronic variants. Here, we retrospectively investigated the spectrum of NF1 deep intronic PVs in a cohort of 8,090 unrelated individuals from the University of Alabama at Birmingham (UAB) dataset with a molecularly confirmed neurofibromatosis type 1. All variants were identified through their effect on the NF1 transcript, followed by variant characterization at the DNA-level. A total of 68 distinct variants, which were ≥ 20 nucleotides away from the closest exon-intron junction, were identified in 2.5% unrelated individuals with NF1 (200/8,090). Nine different pathogenic splice variants, identified in 20 probands, led to exonization of different parts of intron 30 [23.2] or 31 [23a]. The two major NF1 transcript isoforms, distinguished by the absence (type I) or presence (type II) of the alternatively spliced cassette exon 31 [23a], are equally expressed in blood in control individuals without NF1 or NF1-affected individuals carrying their PV not in the introns flanking exon 31 [23a]. By fragment and cloning analysis we demonstrated that the exonization of intron 31 [23a] sequences due to deep intronic PV predominantly affects the NF1 isoform II. Seven additional (likely) pathogenic NF1 deep intronic variants not observed in the UAB dataset were found by classification of 36 variants identified by a literature search. Hence, the unique list of these 75 deep intronic (likely) PVs should be included in any comprehensive NF1 testing strategy.


Assuntos
Neurofibromatose 1 , Humanos , Neurofibromatose 1/genética , Íntrons/genética , Estudos Retrospectivos , Éxons/genética , Fenótipo , Isoformas de Proteínas/genética
5.
BMC Oral Health ; 23(1): 138, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36894923

RESUMO

BACKGROUND: The anatomical position of the mandibular third molars (M3s) is located in the distal-most portions of the molar area. In some previous literature, researchers evaluated the relationship between retromolar space (RS) and different classifications of M3 in three­dimensional (3D) cone-beam computed tomography (CBCT). METHODS: Two hundred six M3s from 103 patients were included. M3s were grouped according to four classification criteria: PG-A/B/C, PG-I/II/III, mesiodistal angle and buccolingual angle. 3D hard tissue models were reconstructed by CBCT digital imaging. RS was measured respectively by utilizing the fitting WALA ridge plane (WP) which was fitted by the least square method and the occlusal plane (OP) as reference planes. SPSS (version 26) was used to analyze the data. RESULTS: In all criteria evaluated, RS decreased steadily from the crown to the root (P < 0.05), the minimum was at the root tip. From PG-A classification, PG-B classification to PG-C classification and from PG-I classification, PG-II classification to PG-III classification, RS both appeared a diminishing tendency (P < 0.05). As the degree of mesial tilt decreased, RS appeared an increasing trend (P < 0.05). RS in classification criteria of buccolingual angle had no statistical difference (P > 0.05). CONCLUSIONS: RS was associated with positional classifications of the M3. In the clinic, RS can be evaluated by watching the Pell&Gregory classification and mesial angle of M3.


Assuntos
Dente Serotino , Dente Impactado , Humanos , Adulto , Dente Serotino/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Coroa do Dente , Tomografia Computadorizada de Feixe Cônico/métodos
6.
Hum Mutat ; 43(1): 74-84, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34747535

RESUMO

Constitutional LZTR1 or SMARCB1 pathogenic variants (PVs) have been found in ∼86% of familial and ∼40% of sporadic schwannomatosis cases. Hence, we performed massively parallel sequencing of the entire LZTR1, SMARCB1, and NF2 genomic loci in 35 individuals with schwannomas negative for constitutional first-hit PVs in the LZTR1/SMARCB1/NF2 coding sequences; however, with 22q deletion and/or a different NF2 PV in each tumor, including six cases with only one tumor available. Furthermore, we verified whether any other LZTR1/SMARCB1/NF2 (likely) PVs could be found in 16 cases carrying a SMARCB1 constitutional variant in the 3'-untranslated region (3'-UTR) c.*17C>T, c.*70C>T, or c.*82C>T. As no additional variants were found, functional studies were performed to clarify the effect of these 3'-UTR variants on the transcript. The 3'-UTR variants c.*17C>T and c.*82C>T showed pathogenicity by negatively affecting the SMARCB1 transcript level. Two novel deep intronic SMARCB1 variants, c.500+883T>G and c.500+887G>A, resulting in out-of-frame missplicing of intron 4, were identified in two unrelated individuals. Further resequencing of the entire repeat-masked genomics sequences of chromosome 22q in individuals negative for PVs in the SMARCB1/LZTR1/NF2 coding- and noncoding regions revealed five potential schwannomatosis-predisposing candidate genes, that is, MYO18B, NEFH, SGSM1, SGSM3, and SBF1, pending further verification.


Assuntos
Neurilemoma , Neurofibromatoses , Cromossomos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neurilemoma/genética , Neurilemoma/patologia , Neurofibromatoses/genética , Proteína SMARCB1/genética , Fatores de Transcrição/genética
7.
Am J Hum Genet ; 102(1): 69-87, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29290338

RESUMO

Neurofibromatosis type 1 (NF1), a common genetic disorder with a birth incidence of 1:2,000-3,000, is characterized by a highly variable clinical presentation. To date, only two clinically relevant intragenic genotype-phenotype correlations have been reported for NF1 missense mutations affecting p.Arg1809 and a single amino acid deletion p.Met922del. Both variants predispose to a distinct mild NF1 phenotype with neither externally visible cutaneous/plexiform neurofibromas nor other tumors. Here, we report 162 individuals (129 unrelated probands and 33 affected relatives) heterozygous for a constitutional missense mutation affecting one of five neighboring NF1 codons-Leu844, Cys845, Ala846, Leu847, and Gly848-located in the cysteine-serine-rich domain (CSRD). Collectively, these recurrent missense mutations affect ∼0.8% of unrelated NF1 mutation-positive probands in the University of Alabama at Birmingham (UAB) cohort. Major superficial plexiform neurofibromas and symptomatic spinal neurofibromas were more prevalent in these individuals compared with classic NF1-affected cohorts (both p < 0.0001). Nearly half of the individuals had symptomatic or asymptomatic optic pathway gliomas and/or skeletal abnormalities. Additionally, variants in this region seem to confer a high predisposition to develop malignancies compared with the general NF1-affected population (p = 0.0061). Our results demonstrate that these NF1 missense mutations, although located outside the GAP-related domain, may be an important risk factor for a severe presentation. A genotype-phenotype correlation at the NF1 region 844-848 exists and will be valuable in the management and genetic counseling of a significant number of individuals.


Assuntos
Códon/genética , Estudos de Associação Genética , Mutação de Sentido Incorreto/genética , Neurofibromatose 1/genética , Neurofibromina 1/genética , Adolescente , Sequência de Aminoácidos , Criança , Estudos de Coortes , Simulação por Computador , Demografia , Feminino , Heterozigoto , Humanos , Masculino , Neurofibromina 1/química , Fenótipo , Adulto Jovem
8.
Hum Mutat ; 41(6): 1145-1156, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32126153

RESUMO

Uncovering frequent motives of action by which variants impair 3' splice site (3'ss) recognition and selection is essential to improve our understanding of this complex process. Through several mini-gene experiments, we demonstrate that the pyrimidine (Y) to purine (R) transversion NM_000267.3(NF1):c.1722-11T>G, although expected to weaken the polypyrimidine tract, causes exon skipping primarily by introducing a novel AG in the AG-exclusion zone (AGEZ) between the authentic 3'ss AG and the branch point. Evaluation of 90 additional noncanonical intronic NF1 3'ss mutations confirmed that 63% of all mutations and 89% (49/55) of the single-nucleotide variants upstream of positions -3 interrupt the AGEZ. Of these AGEZ-interrupting mutations, 24/49 lead to exon skipping suggesting that absence of AG in this region is necessary for accurate 3'ss selection already in the initial steps of splicing. The analysis of 91 noncanonical NF1 3'ss mutations also shows that 90% either introduce a novel AG in the AGEZ, cause a Y>R transversion at position -3 or remove ≥2 Ys in the AGEZ. We confirm in a validation cohort that these three motives distinguish spliceogenic from splice-neutral variants with 85% accuracy and, therefore, are generally applicable to select among variants of unknown significance those likely to affect splicing.


Assuntos
Íntrons , Neurofibromina 1/genética , Sítios de Splice de RNA , Splicing de RNA , Adulto , Processamento Alternativo , Sequência de Bases , Éxons , Feminino , Humanos , Mutação , Ribonucleoproteínas Nucleares Pequenas/genética
9.
Hum Mutat ; 41(1): 299-315, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31595648

RESUMO

We report 281 individuals carrying a pathogenic recurrent NF1 missense variant at p.Met1149, p.Arg1276, or p.Lys1423, representing three nontruncating NF1 hotspots in the University of Alabama at Birmingham (UAB) cohort, together identified in 1.8% of unrelated NF1 individuals. About 25% (95% confidence interval: 20.5-31.2%) of individuals heterozygous for a pathogenic NF1 p.Met1149, p.Arg1276, or p.Lys1423 missense variant had a Noonan-like phenotype, which is significantly more compared with the "classic" NF1-affected cohorts (all p < .0001). Furthermore, p.Arg1276 and p.Lys1423 pathogenic missense variants were associated with a high prevalence of cardiovascular abnormalities, including pulmonic stenosis (all p < .0001), while p.Arg1276 variants had a high prevalence of symptomatic spinal neurofibromas (p < .0001) compared with "classic" NF1-affected cohorts. However, p.Met1149-positive individuals had a mild phenotype, characterized mainly by pigmentary manifestations without externally visible plexiform neurofibromas, symptomatic spinal neurofibromas or symptomatic optic pathway gliomas. As up to 0.4% of unrelated individuals in the UAB cohort carries a p.Met1149 missense variant, this finding will contribute to more accurate stratification of a significant number of NF1 individuals. Although clinically relevant genotype-phenotype correlations are rare in NF1, each affecting only a small percentage of individuals, together they impact counseling and management of a significant number of the NF1 population.


Assuntos
Alelos , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação de Sentido Incorreto , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/genética , Neurofibromina 1/genética , Substituição de Aminoácidos , Estudos Transversais , Heterozigoto , Humanos , Fenótipo
10.
Genet Med ; 22(12): 2081-2088, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32773772

RESUMO

PURPOSE: Biallelic germline mismatch repair (MMR) gene pathogenic variants (PVs) cause constitutional MMR deficiency (CMMRD), a highly penetrant childhood cancer syndrome phenotypically overlapping with neurofibromatosis type 1 (NF1). CMMRD testing in suspected NF1 children without NF1/SPRED1 PVs enables inclusion of CMMRD positives into monitoring programs prior to tumor onset. However, testing is associated with potential harms and the prevalence of CMMRD among these children is unknown. METHODS: Using a simple and scalable microsatellite instability (MSI) assay of non-neoplastic leukocyte DNA to detect CMMRD, we retrospectively screened >700 children suspected of sporadic NF1 but lacking NF1/SPRED1 PVs. RESULTS: For three of seven MSI-positive patients germline MMR gene PVs confirmed the diagnosis of CMMRD. Founder variants NM_000535.5(PMS2):c.736_741delinsTGTGTGTGAAG, prevalent in Europe and North America, and NM_000179.2(MSH6):c.10C>G, affecting 1:400 French Canadians, represented two of five PVs. The prevalence of CMMRD was 3/735 (0.41%, 95% confidence interval [CI]: 0.08-1.19%). CONCLUSION: Our empirical data provide reliable numbers for genetic counseling and confirm previous prevalence estimations, on which Care for CMMRD consortium guidelines are based. These advocate CMMRD testing of preselected patients rather than offering reflex testing to all suspected sporadic NF1 children lacking NF1/SPRED1 PVs. The possibility of founder effects should be considered alongside these testing guidelines.


Assuntos
Neoplasias Colorretais , Neurofibromatose 1 , Proteínas Adaptadoras de Transdução de Sinal , Neoplasias Encefálicas , Canadá , Criança , Reparo de Erro de Pareamento de DNA/genética , Europa (Continente) , Humanos , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Síndromes Neoplásicas Hereditárias , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/epidemiologia , Neurofibromatose 1/genética , América do Norte , Estudos Retrospectivos
12.
Genet Med ; 21(4): 867-876, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30190611

RESUMO

PURPOSE: Neurofibromatosis type 1 (NF1) is characterized by a highly variable clinical presentation, but almost all NF1-affected adults present with cutaneous and/or subcutaneous neurofibromas. Exceptions are individuals heterozygous for the NF1 in-frame deletion, c.2970_2972del (p.Met992del), associated with a mild phenotype without any externally visible tumors. METHODS: A total of 135 individuals from 103 unrelated families, all carrying the constitutional NF1 p.Met992del pathogenic variant and clinically assessed using the same standardized phenotypic checklist form, were included in this study. RESULTS: None of the individuals had externally visible plexiform or histopathologically confirmed cutaneous or subcutaneous neurofibromas. We did not identify any complications, such as symptomatic optic pathway gliomas (OPGs) or symptomatic spinal neurofibromas; however, 4.8% of individuals had nonoptic brain tumors, mostly low-grade and asymptomatic, and 38.8% had cognitive impairment/learning disabilities. In an individual with the NF1 constitutional c.2970_2972del and three astrocytomas, we provided proof that all were NF1-associated tumors given loss of heterozygosity at three intragenic NF1 microsatellite markers and c.2970_2972del. CONCLUSION: We demonstrate that individuals with the NF1 p.Met992del pathogenic variant have a mild NF1 phenotype lacking clinically suspected plexiform, cutaneous, or subcutaneous neurofibromas. However, learning difficulties are clearly part of the phenotypic presentation in these individuals and will require specialized care.


Assuntos
Deficiências da Aprendizagem/genética , Neurofibroma Plexiforme/genética , Neurofibromatose 1/genética , Neurofibromina 1/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Heterozigoto , Humanos , Lactente , Deficiências da Aprendizagem/fisiopatologia , Masculino , Mutação de Sentido Incorreto/genética , Neurofibroma Plexiforme/fisiopatologia , Neurofibromatose 1/patologia , Deleção de Sequência , Adulto Jovem
13.
FASEB J ; 31(10): 4434-4446, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28646018

RESUMO

The amyloid precursor protein (APP) has long been appreciated for its role in Alzheimer's disease (AD) pathology. However, less is known about the physiologic function of APP outside of AD. Particularly, whether and how APP may regulate functions of cell surface receptors, including GPCRs, remains largely unclear. In this study, we identified a novel direct interaction between APP and the α2A-adrenergic receptor (α2AAR) that occurs at the intracellular domains of both proteins. The APP interaction with α2AAR is promoted by agonist stimulation and competes with arrestin 3 binding to the receptor. Consequently, the presence of APP attenuates α2AAR internalization and desensitization, which are arrestin-dependent processes. Furthermore, in neuroblastoma neuro-2A cells and primary superior cervical ganglion neurons, where APP is highly expressed, the lack of APP leads to a dramatic increase in plasma membrane recruitment of endogenous arrestin 3 following α2AAR activation. Concomitantly, agonist-induced internalization of α2AAR is significantly enhanced in these neuronal cells. Our study provided the first evidence that APP fine tunes GPCR signaling and trafficking. Given the important role of α2AAR in controlling norepinephrine release and response, this novel regulation of α2AAR by APP may have an impact on modulation of noradrenergic activity and sympathetic tone.-Zhang, F., Gannon, M., Chen, Y., Zhou, L., Jiao, K., Wang, Q. The amyloid precursor protein modulates α2A-adrenergic receptor endocytosis and signaling through disrupting arrestin 3 recruitment.


Assuntos
Arrestinas/metabolismo , Endocitose/efeitos dos fármacos , Neurônios/metabolismo , Receptores Adrenérgicos alfa 2/metabolismo , beta-Arrestina 2/metabolismo , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/farmacologia , Animais , Endocitose/fisiologia , Camundongos , Transporte Proteico/fisiologia , Transdução de Sinais/fisiologia
14.
BMC Oral Health ; 18(1): 107, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29895270

RESUMO

BACKGROUND: Teeth treated endodontically are more susceptible to vertical root fracture (VRF). Some studies have suggested that obturating the root canals with Gutta-percha or Resilon can reinforce endodontically treated teeth, but a few others have presented conflicting results. These inconsistent results cannot guide clinicians in determining clinical approaches. The objective of this meta-analysis is to evaluate and compare the vertical fracture resistance of endodontically treated root canals obturated with Gutta-percha/AH plus and the Resilon system. METHODS: Comprehensive literature searches were performed in the PubMed, Cochrane Library, ScienceDirect, Web of Science and Embase databases. The titles and abstracts of all of the retrieved articles were independently assessed by two authors according to predefined selection criteria. Data in the included articles were independently extracted. Statistical analyses were conducted using Review Manager 5.3 and Stata 12.0 software. The pooled standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated for the outcome indicators. The level of statistical significance was set at p < 0.05. The Cochran Q test (I2 test) was used to test for heterogeneity among studies. RESULTS: Fourteen randomized controlled in vitro trials were included in the meta-analysis. The results demonstrated that the vertical root fracture resistance of unprepared and unfilled roots was significantly higher than that of roots obturated with Gutta-percha/AH plus (SMD = - 0.69, 95% CI = - 1.34 to - 0.04, p = 0.04) or the Resilon system (SMD = - 0.54, 95% CI = - 1.07 to - 0.00, p = 0.05). The differences in fracture resistance between the roots filled with Gutta-percha/AH plus and the prepared unfilled root canals was not significant (SMD = 0.59, 95% CI = - 0.02 to 1.21, p = 0.06). Roots obturated with Resilon had higher fracture resistance than instrumented unfilled roots (SMD = 0.83, 95% CI = 0.44 to 1.22, p < 0.0001) or roots filled with Gutta-percha/AH plus (SMD = 0.62, 95% CI = 0.01 to 1.23, p = 0.05). CONCLUSIONS: The present study suggests that filling with Gutta-percha/AH plus dose not reinforce endodontically treated roots, whereas obturating with the Resilon system can increase vertical root fracture resistance of prepared roots. As this meta-analysis was based on in vitro studies, it should be careful to extrapolate its conclusion to the clinical context.


Assuntos
Restauração Dentária Permanente , Guta-Percha/uso terapêutico , Materiais Restauradores do Canal Radicular/uso terapêutico , Fraturas dos Dentes/prevenção & controle , Dente não Vital/patologia , Restauração Dentária Permanente/efeitos adversos , Restauração Dentária Permanente/métodos , Análise do Estresse Dentário , Humanos , Técnicas In Vitro , Fraturas dos Dentes/etiologia
15.
Mol Pharmacol ; 92(6): 630-639, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28954816

RESUMO

The adenosine A1 receptor (A1R) is a key mediator of the neuroprotective effect by endogenous adenosine. Yet targeting this receptor for neuroprotection is challenging due to its broad expression throughout the body. A mechanistic understanding of the regulation of A1R signaling is necessary for the future design of therapeutic agents that can selectively enhance A1R-mediated responses in the nervous system. In this study, we demonstrate that A1R activation leads to a sustained localization of regulator of G protein signaling 4 (RGS4) at the plasma membrane, a process that requires neurabin (a neural tissue-specific protein). A1R and RGS4 interact with the overlapping regions of neurabin. In addition, neurabin domains required for oligomerization are essential for formation of the A1R/neurabin/RGS4 ternary complex, as well as for stable localization of RGS4 at the plasma membrane and attenuation of A1R signaling. Thus, A1R and RGS4 each likely interact with one neurabin molecule in a neurabin homo-oligomer to form a ternary complex, representing a novel mode of regulation of G protein-coupled receptor signaling by scaffolding proteins. Our mechanistic analysis of neurabin-mediated regulation of A1R signaling in this study will be valuable for the future design of therapeutic agents that can selectively enhance A1R-mediated responses in the nervous system.


Assuntos
Proteínas dos Microfilamentos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptor A1 de Adenosina/metabolismo , Animais , Células COS , Membrana Celular/metabolismo , Chlorocebus aethiops , Células HEK293 , Humanos , Complexos Multiproteicos/metabolismo , Domínios Proteicos , Multimerização Proteica , Transporte Proteico , Proteínas RGS/metabolismo , Transdução de Sinais
16.
Proc Natl Acad Sci U S A ; 111(48): 17296-301, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25404298

RESUMO

Accumulation of amyloid ß (Aß) peptides in the brain is the key pathogenic factor driving Alzheimer's disease (AD). Endocytic sorting of amyloid precursor protein (APP) mediated by the vacuolar protein sorting (Vps10) family of receptors plays a decisive role in controlling the outcome of APP proteolytic processing and Aß generation. Here we report for the first time to our knowledge that this process is regulated by a G protein-coupled receptor, the α(2A) adrenergic receptor (α(2A)AR). Genetic deficiency of the α(2A)AR significantly reduces, whereas stimulation of this receptor enhances, Aß generation and AD-related pathology. Activation of α(2A)AR signaling disrupts APP interaction with a Vps10 family receptor, sorting-related receptor with A repeat (SorLA), in cells and in the mouse brain. As a consequence, activation of α(2A)AR reduces Golgi localization of APP and concurrently promotes APP distribution in endosomes and cleavage by ß secretase. The α(2A)AR is a key component of the brain noradrenergic system. Profound noradrenergic dysfunction occurs consistently in patients at the early stages of AD. α(2A)AR-promoted Aß generation provides a novel mechanism underlying the connection between noradrenergic dysfunction and AD. Our study also suggests α(2A)AR as a previously unappreciated therapeutic target for AD. Significantly, pharmacological blockade of the α(2A)AR by a clinically used antagonist reduces AD-related pathology and ameliorates cognitive deficits in an AD transgenic model, suggesting that repurposing clinical α(2A)R antagonists would be an effective therapeutic strategy for AD.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Amiloide/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Receptores Adrenérgicos alfa 2/metabolismo , Receptores de LDL/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Western Blotting , Encéfalo/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Modelos Animais de Doenças , Células HEK293 , Humanos , Proteínas de Membrana Transportadoras/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Microscopia Confocal , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Receptores Adrenérgicos alfa 2/genética , Receptores de LDL/genética
17.
Hum Mol Genet ; 23(8): 2145-56, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24293546

RESUMO

Haploinsufficiency for CHD7, an ATP-dependent nucleosome remodeling factor, is the leading cause of CHARGE syndrome. While congenital heart defects (CHDs) are major clinical features of CHARGE syndrome, affecting >75% of patients, it remains unclear whether CHD7 can directly regulate cardiogenic genes in embryos. Our complementary yeast two-hybrid and biochemical assays reveal that CHD7 is a novel interaction partner of canonical BMP signaling pathway nuclear mediators, SMAD1/5/8, in the embryonic heart. Moreover, CHD7 associates in a BMP-dependent manner with the enhancers of a critical cardiac transcription factor, Nkx2.5, that contain functional SMAD1-binding elements. Both the active epigenetic signature of Nkx2.5 regulatory elements and its proper expression in cardiomyocytes require CHD7. Finally, inactivation of Chd7 in mice impairs multiple BMP signaling-regulated cardiogenic processes. Our results thus support the model that CHD7 is recruited by SMAD1/5/8 to the enhancers of BMP-targeted cardiogenic genes to epigenetically regulate their expression. Impaired BMP activities in embryonic hearts may thus have a major contribution to CHDs in CHARGE syndrome.


Assuntos
Proteína Morfogenética Óssea 1/metabolismo , Proteínas de Ligação a DNA/fisiologia , Embrião de Mamíferos/metabolismo , Epigenômica , Coração/embriologia , Proteínas de Homeodomínio/genética , Proteínas Smad Reguladas por Receptor/metabolismo , Fatores de Transcrição/genética , Animais , Western Blotting , Proteína Morfogenética Óssea 1/genética , Células Cultivadas , Imunoprecipitação da Cromatina , Embrião de Mamíferos/citologia , Regulação da Expressão Gênica no Desenvolvimento , Proteína Homeobox Nkx-2.5 , Proteínas de Homeodomínio/metabolismo , Técnicas Imunoenzimáticas , Imunoprecipitação , Camundongos , Organogênese/fisiologia , Ligação Proteica , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Elementos Reguladores de Transcrição , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Proteínas Smad Reguladas por Receptor/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Técnicas do Sistema de Duplo-Híbrido
18.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 41(4): 394-8, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-27241150

RESUMO

OBJECTIVE: To establish the Chinese Han national criteria for the thickness of upper lip in Chongqing and to investigate the effect of lip thickness on lip retraction in orthodontic treatment.
 METHODS: A total of 240 adult patients (male=120, female=120) of Chinese Han nationality aged 18-35 years in Chongqing were treated with cephalograms and measured the thickness of upper lip. We established the Chinese Han national criteria for the thickness of upper lip in Chongqing according to the results. Sixty-eight female patients with Angle II 1 from Department of Orthodontics Stomatological Hospital of Chongqing Medical University were treated with maxillary premolars extraction, and pre- and post-treated with lateral cephalograms, then divided into 3 groups according to our criteria: a thin lips group, a normal lips group and a thick lips group. The ratio of the incisors retraction and the upper lip retraction were measured and calculated. The correlation between incisors retraction and the upper lip retraction was analyzed by the Pearson correlation method.
 RESULTS: There was statistical significance in the thickness of upper lip between males and females (P<0.01). The ratio of maxillary inscior retraction to the upper lip soft tissue retraction was 1.6:1, 2.2:1 and 2.9:1 in the thin lips group, the normal lips group and the thick lips group, respectively.
 CONCLUSION: Gender differences exist in the thickness of upper lip. Upper lip retraction with the incisors was negatively correlated with the soft tissue thickness of the upper lip in females with Angle II 1.


Assuntos
Lábio/anatomia & histologia , Extração Dentária , Adolescente , Adulto , Dente Pré-Molar , Cefalometria , Feminino , Humanos , Incisivo , Masculino , Adulto Jovem
19.
Hum Mutat ; 36(11): 1052-63, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26178382

RESUMO

Neurofibromatosis type 1 (NF1) is one of the most frequent genetic disorders, affecting 1:3,000 worldwide. Identification of genotype-phenotype correlations is challenging because of the wide range clinical variability, the progressive nature of the disorder, and extreme diversity of the mutational spectrum. We report 136 individuals with a distinct phenotype carrying one of five different NF1 missense mutations affecting p.Arg1809. Patients presented with multiple café-au-lait macules (CALM) with or without freckling and Lisch nodules, but no externally visible plexiform neurofibromas or clear cutaneous neurofibromas were found. About 25% of the individuals had Noonan-like features. Pulmonic stenosis and short stature were significantly more prevalent compared with classic cohorts (P < 0.0001). Developmental delays and/or learning disabilities were reported in over 50% of patients. Melanocytes cultured from a CALM in a segmental NF1-patient showed two different somatic NF1 mutations, p.Arg1809Cys and a multi-exon deletion, providing genetic evidence that p.Arg1809Cys is a loss-of-function mutation in the melanocytes and causes a pigmentary phenotype. Constitutional missense mutations at p.Arg1809 affect 1.23% of unrelated NF1 probands in the UAB cohort, therefore this specific NF1 genotype-phenotype correlation will affect counseling and management of a significant number of patients.


Assuntos
Substituição de Aminoácidos , Códon , Mutação de Sentido Incorreto , Neurofibromina 1/genética , Síndrome de Noonan/diagnóstico , Síndrome de Noonan/genética , Fenótipo , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Nanismo/genética , Feminino , Estudos de Associação Genética , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Neurofibromina 1/química , Adulto Jovem
20.
Ann Neurol ; 75(1): 77-87, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24114805

RESUMO

OBJECTIVE: Autosomal dominant cortical myoclonus and epilepsy (ADCME) is characterized by distal, fairly rhythmic myoclonus and epilepsy with variable severity. We have previously mapped the disease locus on chromosome 2p11.1-q12.2 by genome-wide linkage analysis. Additional pedigrees affected by similar forms of epilepsy have been associated with chromosomes 8q, 5p, and 3q, but none of the causing genes has been identified. We aim to identify the mutant gene responsible for this form of epilepsy. METHODS: Genes included in the ADCME critical region were directly sequenced. Coimmunoprecipitation, immunofluorescent, and electrophysiologic approaches to transfected human cells have been utilized for testing the functional significance of the identified mutation. RESULTS: Here we show that mutation in the α2 -adrenergic receptor subtype B (α2B -AR) is associated with ADCME by identifying a novel in-frame insertion/deletion in 2 Italian families. The mutation alters several conserved residues of the third intracellular loop, hampering neither the α2B -AR plasma membrane localization nor the arrestin-mediated internalization capacity, but altering the binding with the scaffolding protein spinophilin upon neurotransmitter activation. Spinophilin, in turn, regulates interaction of G protein coupled receptors with regulator of G protein signaling proteins. Accordingly, the mutant α2B -AR increases the epinephrine-stimulated calcium signaling. INTERPRETATION: The identified mutation is responsible for ADCME, as the loss of α2B -AR/spinophilin interaction causes a gain of function effect. This work implicates for the first time the α-adrenergic system in human epilepsy and opens new ways of understanding the molecular pathway of epileptogenesis, widening the spectrum of possible therapeutic targets.


Assuntos
Epilepsias Mioclônicas/diagnóstico , Epilepsias Mioclônicas/genética , Mutação/genética , Receptores Adrenérgicos alfa 2/genética , Sequência de Aminoácidos , Animais , Células COS , Chlorocebus aethiops , Epilepsias Mioclônicas/fisiopatologia , Potenciais Somatossensoriais Evocados/fisiologia , Feminino , Células HeLa , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Receptores Adrenérgicos alfa 2/química , Xenopus laevis
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