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1.
Hum Mol Genet ; 32(7): 1162-1174, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36345169

RESUMO

ADP-ribosylation factor 1 (ARF1) is a small GTPase that regulates membrane traffic at the Golgi apparatus and endosomes through recruitment of several coat proteins and lipid-modifying enzymes. Here, we report a pediatric patient with an ARF1-related disorder because of a monoallelic de novo missense variant (c.296 G > A; p.R99H) in the ARF1 gene, associated with developmental delay, hypotonia, intellectual disability and motor stereotypies. Neuroimaging revealed a hypoplastic corpus callosum and subcortical white matter abnormalities. Notably, this patient did not exhibit periventricular heterotopias previously observed in other patients with ARF1 variants (including p.R99H). Functional analysis of the R99H-ARF1 variant protein revealed that it was expressed at normal levels and properly localized to the Golgi apparatus; however, the expression of this variant caused swelling of the Golgi apparatus, increased the recruitment of coat proteins such as coat protein complex I, adaptor protein complex 1 and GGA3 and altered the morphology of recycling endosomes. In addition, we observed that the expression of R99H-ARF1 prevented dispersal of the Golgi apparatus by the ARF1-inhibitor brefeldin A. Finally, protein interaction analyses showed that R99H-ARF1 bound more tightly to the ARF1-effector GGA3 relative to wild-type ARF1. These properties were similar to those of the well-characterized constitutively active Q71L-ARF1 mutant, indicating that the pathogenetic mechanism of the R99H-ARF1 variant involves constitutive activation with resultant Golgi and endosomal alterations. The absence of periventricular nodular heterotopias in this R99H-ARF1 subject also indicates that this finding may not be a consistent phenotypic expression of all ARF1-related disorders.


Assuntos
Fator 1 de Ribosilação do ADP , Transtornos do Neurodesenvolvimento , Humanos , Animais , Camundongos , Fator 1 de Ribosilação do ADP/química , Fator 1 de Ribosilação do ADP/genética , Fator 1 de Ribosilação do ADP/metabolismo , Mutação de Sentido Incorreto , Feminino , Criança , Complexo de Golgi/patologia , Endossomos/patologia , Transtornos do Neurodesenvolvimento/diagnóstico , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/patologia
2.
J Cell Physiol ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38924572

RESUMO

There is no doubt that navigating academia is a formidable challenge, particularly for those from underrepresented backgrounds who face additional barriers at every turn. In such an environment, efforts to create learning and training environments that are diverse, equitable, and inclusive can feel like an uphill battle. We believe that harnessing the power of artificial intelligence (AI) tools can help in leveling the playing field. While AI cannot supplant the need for supportive mentorship, it can serve as a vital supplement, offering guidance and assistance to those who may lack access to adequate avenues of support. Embracing AI in this context should not be stigmatized, as it may represent a vital lifeline for underrepresented individuals who often face systemic biases while forging their own paths in pursuit of success and belonging in academia. AI tools should not be gatekept from these individuals, particularly by those in positions of power and privilege within the scientific community. Instead, we argue, institutions should make a strong commitment to educating their community members on how to ethically harness these tools.

3.
Orthod Craniofac Res ; 27(2): 203-210, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37525623

RESUMO

OBJECTIVE: To describe a method to calculate the total intra-articular volume (inter-osseous space) of the temporomandibular joint (TMJ) determined by cone-beam computed tomography (CBCT). This could be used as a marker of tissue proliferation and different degrees of soft tissue hyperplasia in juvenile idiopathic arthritis (JIA) patients. MATERIALS AND METHODS: Axial single-slice CBCT images of cross-sections of the TMJs of 11 JIA patients and 11 controls were employed. From the top of the glenoid fossa, in the caudal direction, an average of 26 slices were defined in each joint (N = 44). The interosseous space was manually delimited from each slice by using dedicated software that includes a graphic interface. TMJ volumes were calculated by adding the areas measured in each slice. Two volumes were defined: Ve-i and Vi , where Ve-i is the inter-osseous space, volume defined by the borders of the fossa and Vi is the internal volume defined by the condyle. An intra-articular volume filling index (IF) was defined as Ve-i /Vi , which represents the filling of the space. RESULTS: The measured space of the intra-articular volume, corresponding to the intra-articular soft tissue and synovial fluid, was more than twice as large in the JIA group as in the control group. CONCLUSION: The presented method, based on CBCT, is feasible for assessing inter-osseus joint volume of the TMJ and delimits a threshold of intra-articular changes related to intra-articular soft tissue proliferation, based on differences in volumes. Intra-articular soft tissue is found to be enlarged in JIA patients.


Assuntos
Artrite Juvenil , Transtornos da Articulação Temporomandibular , Humanos , Artrite Juvenil/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Articulação Temporomandibular/diagnóstico por imagem , Côndilo Mandibular/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos
4.
Rev Esp Enferm Dig ; 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38205691

RESUMO

Gastrointestinal stromal tumors (GIST) are rare mesenchymal tumors of the gastrointestinal tract and a rare cause of gastrointestinal bleeding. These tumors usually affect people over 50 years of age and they exhibit a wide range of clinical manifestations, including asymptomatic patients, nonspecific symptoms, obstruction or bleeding, which may delay diagnosis. Early diagnosis and treatment are crucial because GISTs can be aggressive and metastasize. This case highlights the importance of considering GISTs in the differential diagnosis of obscure gastrointestinal bleeding.

5.
Rev Esp Enferm Dig ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767031

RESUMO

Retrograde upper esophageal sphincter dysfunction (R-UESD) is characterized by the inability to belch. Evidence of using high-resolution manometry (HRM) in diagnosing R-UESD has emerged in recent years. We describe the clinical picture and HRM patterns of two patients with R-UESD. Case 1: A 23-year-old female presented with a two-year complaint of inability to belch. We performed HRM with a belch provocation test for which the patient drank 500 ml of carbonated water. The study revealed increased esophageal pressure, an absence of UES relaxation and secondary peristalsis once the patient mentioned the need to belch. Case 2: A 21-year-old male presented to our medical office with a history of an incapacity to belch during the last three years. We performed HRM with a belch provocation test. During the study, he reported an incapacity to belch and his symptoms coincided with increased esophageal pressure, an absence of UES relaxation, and secondary peristalsis. Retrograde upper esophageal sphincter dysfunction is a rare condition characterized by a lack of UES relaxation during esophageal distension. The incapacity to belch is the hallmark of the disease. We encourage the use of HRM, looking for an increase in esophageal pressure to the level of gastric pressure, failure of UES relaxation with consequently no venting of air across the UES, and secondary peristalsis. In conclusion, diverse R-UESD clinical presentations represent a diagnostic challenge for physicians. This case series highlights the need to actively search for typical HRM findings when encountering patients referring an incapacity to belch.

6.
Development ; 147(8)2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32265198

RESUMO

Endocannabinoids (eCB) modulate growth cone dynamics and axonal pathfinding through the stimulation of cannabinoid type-1 receptors (CB1R), the function of which depends on their delivery and precise presentation at the growth cone surface. However, the mechanism involved in the axonal transport of CB1R and its transport role in eCB signaling remains elusive. As mutations in the kinesin-1 molecular motor have been identified in patients with abnormal cortical development and impaired white matter integrity, we studied the defects in axonal pathfinding and fasciculation in mice lacking the kinesin light chain 1 (Klc1-/-) subunit of kinesin-1. Reduced levels of CB1R were found in corticofugal projections and axonal growth cones in Klc1-/- mice. By live-cell imaging of CB1R-eGFP we characterized the axonal transport of CB1R vesicles and described the defects in transport that arise after KLC1 deletion. Cofilin activation, which is necessary for actin dynamics during growth cone remodeling, is impaired in the Klc1-/- cerebral cortex. In addition, Klc1-/- neurons showed expanded growth cones that were unresponsive to CB1R-induced axonal elongation. Together, our data reveal the relevance of kinesin-1 in CB1R axonal transport and in eCB signaling during brain wiring.


Assuntos
Transporte Axonal , Axônios/metabolismo , Canabinoides/metabolismo , Cinesinas/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Animais , Axônios/ultraestrutura , Córtex Cerebral/metabolismo , Deleção de Genes , Cones de Crescimento/metabolismo , Camundongos Endogâmicos C57BL , Subunidades Proteicas/metabolismo , Tálamo/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-37612449

RESUMO

BACKGROUND: There is strong evidence supporting the association between environmental factors and increased risk of non-affective psychotic disorders. However, the use of sound statistical methods to account for spatial variations associated with environmental risk factors, such as urbanicity, migration, or deprivation, is scarce in the literature. METHODS: We studied the geographical distribution of non-affective first-episode psychosis (NA-FEP) in a northern region of Spain (Navarra) during a 54-month period considering area-level socioeconomic indicators as putative explanatory variables. We used several Bayesian hierarchical Poisson models to smooth the standardized incidence ratios (SIR). We included neighborhood-level variables in the spatial models as covariates. RESULTS: We identified 430 NA-FEP cases over a 54-month period for a population at risk of 365,213 inhabitants per year. NA-FEP incidence risks showed spatial patterning and a significant ecological association with the migrant population, unemployment, and consumption of anxiolytics and antidepressants. The high-risk areas corresponded mostly to peripheral urban regions; very few basic health sectors of rural areas emerged as high-risk areas in the spatial models with covariates. DISCUSSION: Increased rates of unemployment, the migrant population, and consumption of anxiolytics and antidepressants showed significant associations linked to the spatial-geographic incidence of NA-FEP. These results may allow targeting geographical areas to provide preventive interventions that potentially address modifiable environmental risk factors for NA-FEP. Further investigation is needed to understand the mechanisms underlying the associations between environmental risk factors and the incidence of NA-FEP.

8.
Int J Mol Sci ; 24(18)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37762529

RESUMO

While cells in the human body function in an environment where the blood supply constantly delivers nutrients and removes waste, cells in conventional tissue culture well platforms are grown with a static pool of media above them and often lack maturity, limiting their utility to study cell biology in health and disease. In contrast, organ-chip microfluidic systems allow the growth of cells under constant flow, more akin to the in vivo situation. Here, we differentiated human induced pluripotent stem cells into dopamine neurons and assessed cellular properties in conventional multi-well cultures and organ-chips. We show that organ-chip cultures, compared to multi-well cultures, provide an overall greater proportion and homogeneity of dopaminergic neurons as well as increased levels of maturation markers. These organ-chips are an ideal platform to study mature dopamine neurons to better understand their biology in health and ultimately in neurological disorders.


Assuntos
Neurônios Dopaminérgicos , Células-Tronco Pluripotentes Induzidas , Humanos , Diferenciação Celular , Células Cultivadas , Técnicas de Cultura de Órgãos
9.
Exp Appl Acarol ; 91(2): 319-330, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37735304

RESUMO

The cattle tick Rhipicephalus (Boophilus) microplus is a major problem of concern for cattle industry in tropical and subtropical areas. Control of cattle tick is based mainly on the use of chemical acaricides, which has contributed to the emerging problem of selection of resistant tick lineages. Plants have been used as an alternative to conventional acaricidal drugs. On the other hand, the acaricidal activity of hydroethanolic extract of Randia aculeata seed (EHRA) has been demonstrated against R. microplus under laboratory conditions. However, the utility of EHRA seed as a potential acaricidal needs to be determined under field conditions. For this reason, the aim of this study was to evaluate the efficacy of the EHRA against R. microplus sprayed on naturally infested calves, determine the effect of the EHRA seed on acetylcholinesterase activity in R. microplus larval and identify the chemical composition of EHRA. Forty-five male calves were divided in three groups and treated with: G1 water; G2 EHRA 20% w/v and G3 coumaphos 0.2% v/v. Acetylcholinesterase (AChE) activity in R. microplus larvae was determined by a colorimetric assay. The chemical composition of EHRA was accessed through HPLC/MS. Significantly fewer ticks were observed after 24 h on the treated group compared to control group. EHRA significantly inhibited in vitro AChE activity in R. microplus at all tested concentrations. Chlorogenic acid, vanillinic acid, p-coumaric acid, caffeic acid. rutin, quercetin, (-)-epicatechin, 4-hydroxybenzoic acid, quercetin, vanillin, 2,4-dimethoxy-6-methylbenzoic acid, scopoletin and ferulic acid were identified in the extract. The results provided new data for the elucidation of the mechanisms of EHRA acaricide action and to further evaluate the use as a new alternative control agent against R. microplus under in vivo conditions.


Assuntos
Acaricidas , Doenças dos Bovinos , Besouros , Ixodidae , Rhipicephalus , Infestações por Carrapato , Animais , Bovinos , Acetilcolinesterase , Quercetina/farmacologia , Quercetina/uso terapêutico , Acaricidas/farmacologia , Sementes , Larva , Extratos Vegetais/farmacologia , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/prevenção & controle , Infestações por Carrapato/tratamento farmacológico , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/veterinária
11.
Rev Esp Enferm Dig ; 115(6): 327-328, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36093969

RESUMO

A 38-year-old male with established diagnosis of stage IV squamous cell carcinoma of the esophagus treated with chemoradiotherapy (25 sessions of 50 Gy), presented with acute aphagia, thoracic pain, productive cough, and mild hemoptysis. Upon physical examination the right hemithorax presented with crepitations. An initial CT scan showed an esophageal perforation. An upper endoscopy was performed, visualizing the esophageal perforation in the mid third of the esophagus at 26 cm of the dental arcade. It was possible to bypass and intubate the stomach, enabling the placement of a guide wire under endoscopic visualization. Afterwards, a partially covered, self-expandable, metal stent (Wallflex esophageal stent 10 cm/18/23; Boston Scientific) was placed in the esophagus restoring continuity, visualized by fluoroscopy.


Assuntos
Neoplasias Esofágicas , Perfuração Esofágica , Masculino , Humanos , Adulto , Perfuração Esofágica/diagnóstico por imagem , Perfuração Esofágica/etiologia , Perfuração Esofágica/terapia , Neoplasias Esofágicas/terapia , Endoscopia , Stents/efeitos adversos , Quimiorradioterapia/efeitos adversos
12.
Rev Esp Enferm Dig ; 115(5): 283-284, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36719344

RESUMO

Pyogenic granuloma is a benign vascular lesion that is most frequently found in the epidermis or mucosa of the oral cavity. Its finding in the ileum is rare, there are only a few case reports. In most reported cases, diagnosis is made with capsule endoscopy or double-balloon enteroscopy. We present a case of a lesion in the ileum, approximately 15 cm from the ileocecal valve, documented by colonoscopy.


Assuntos
Granuloma Piogênico , Valva Ileocecal , Humanos , Valva Ileocecal/diagnóstico por imagem , Granuloma Piogênico/diagnóstico por imagem , Colonoscopia , Íleo/diagnóstico por imagem , Íleo/patologia , Intubação Intratraqueal
13.
Actas Esp Psiquiatr ; 51(1): 21-28, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36912391

RESUMO

The spectrum of suicidal behavior is a core factor of the prognosis and care of Borderline Personality Disorder (BPD). The aim of this study is to identify possible BPD specific personality traits that could act as protective factors of nonsuicidal self-injuries (NSSI.


Assuntos
Transtorno da Personalidade Borderline , Comportamento Autodestrutivo , Humanos , Ideação Suicida , Intenção , Narcisismo , Fatores de Proteção
14.
Psychol Med ; 52(1): 188-194, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32404217

RESUMO

BACKGROUND: The current coronavirus disease (COVID-19) has a great impact worldwide. Healthcare workers play an essential role and are one of the most exposed groups. Information about the psychosocial impact on healthcare workers is limited. METHODS: 3109 healthcare workers completed a national, internet-based, cross-sectional 45-item survey between 9 and 19 April 2020. The objective is to assess the psychological impact of the COVID-19 pandemic in Spanish healthcare workers. A Psychological Stress and Adaptation at work Score (PSAS) was defined combining four modified versions of validated psychological assessment tests (A) Healthcare Stressful Test, (B) Coping Strategies Inventory, (C) Font-Roja Questionnaire and (D) Trait Meta-Mood Scale. RESULTS: The highest psychosocial impact was perceived in Respiratory Medicine, the mean (S.D.) PSAS was 48.3 (13.6) and Geriatrics 47.6 (16.4). Higher distress levels were found in the geographical areas with the highest incidence of COVID-19 (>245.5 cases per 100 000 people), PSAS 46.8 (15.2); p < 0.001. The least stress respondents were asymptomatic workers PSAS, 41.3 (15.4); p < 0.001, as well as those above 60 years old, PSAS, 37.6 (16); p < 0.001. Workers who needed psychological therapy and did not receive it, were more stressed PSAS 52.5 (13.6) than those who did not need it PSAS 39.7 (13.9); p < 0.001. CONCLUSIONS: The psychological impact in healthcare workers in Spain during COVID-19 emergency has been studied. The stress perceived is parallel to the number of cases per 100 000 people. Psychotherapy could have a major role to mitigate the experimented stress level.


Assuntos
COVID-19 , Pandemias , Humanos , Pessoa de Meia-Idade , COVID-19/epidemiologia , Espanha/epidemiologia , Estudos Transversais , Pessoal de Saúde/psicologia
15.
Br J Clin Pharmacol ; 88(4): 1913-1924, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34705297

RESUMO

AIMS: Imatinib is considered the standard first-line treatment in newly diagnosed patients with chronic-phase myeloid leukaemia (CML). Several imatinib population pharmacokinetic (popPK) models have been developed. However, their predictive performance has not been well established when extrapolated to different populations. Therefore, this study aimed to perform an external evaluation of available imatinib popPK models developed mainly in adult patients, and to evaluate the improvement in individual model-based predictions through Bayesian forecasting computed by each model at different treatment occasions. METHODS: A literature review was conducted through PubMed and Scopus to identify popPK models. Therapeutic drug monitoring data collected in adult CML patients treated with imatinib was used for external evaluation, including prediction- and simulated-based diagnostics together with Bayesian forecasting analysis. RESULTS: Fourteen imatinib popPK studies were included for model-performance evaluation. A total of 99 imatinib samples were collected from 48 adult CML patients undergoing imatinib treatment with a minimum of one plasma concentration measured at steady-state between January 2016 and December 2020. The model proposed by Petain et al showed the best performance concerning prediction-based diagnostics in the studied population. Bayesian forecasting demonstrated a significant improvement in predictive performance at the second visit. Inter-occasion variability contributed to reducing bias and improving individual model-based predictions. CONCLUSIONS: Imatinib popPK studies developed in Caucasian subjects including α1-acid glycoprotein showed the best model performance in terms of overall bias and precision. Moreover, two imatinib samples from different visits appear sufficient to reach an adequate model-based individual prediction performance trough Bayesian forecasting.


Assuntos
Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Adulto , Antineoplásicos/farmacocinética , Teorema de Bayes , Monitoramento de Medicamentos , Humanos , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Modelos Biológicos
16.
Brain ; 144(5): 1422-1434, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-33970200

RESUMO

Human 4-hydroxyphenylpyruvate dioxygenase-like (HPDL) is a putative iron-containing non-heme oxygenase of unknown specificity and biological significance. We report 25 families containing 34 individuals with neurological disease associated with biallelic HPDL variants. Phenotypes ranged from juvenile-onset pure hereditary spastic paraplegia to infantile-onset spasticity and global developmental delays, sometimes complicated by episodes of neurological and respiratory decompensation. Variants included bona fide pathogenic truncating changes, although most were missense substitutions. Functionality of variants could not be determined directly as the enzymatic specificity of HPDL is unknown; however, when HPDL missense substitutions were introduced into 4-hydroxyphenylpyruvate dioxygenase (HPPD, an HPDL orthologue), they impaired the ability of HPPD to convert 4-hydroxyphenylpyruvate into homogentisate. Moreover, three additional sets of experiments provided evidence for a role of HPDL in the nervous system and further supported its link to neurological disease: (i) HPDL was expressed in the nervous system and expression increased during neural differentiation; (ii) knockdown of zebrafish hpdl led to abnormal motor behaviour, replicating aspects of the human disease; and (iii) HPDL localized to mitochondria, consistent with mitochondrial disease that is often associated with neurological manifestations. Our findings suggest that biallelic HPDL variants cause a syndrome varying from juvenile-onset pure hereditary spastic paraplegia to infantile-onset spastic tetraplegia associated with global developmental delays.


Assuntos
Oxigenases/genética , Paraplegia Espástica Hereditária/genética , Animais , Feminino , Humanos , Masculino , Camundongos , Mutação , Linhagem , Ratos , Peixe-Zebra
17.
Molecules ; 26(24)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34946651

RESUMO

Immobilization of enzymes has many advantages for their application in biotechnological processes. In particular, the cross-linked enzyme aggregates (CLEAs) allow the production of solid biocatalysts with a high enzymatic loading and the advantage of obtaining derivatives with high stability at low cost. The purpose of this study was to produce cross-linked enzymatic aggregates (CLEAs) of LipMatCCR11, a 43 kDa recombinant solvent-tolerant thermoalkaliphilic lipase from Geobacillus thermoleovorans CCR11. LipMatCCR11-CLEAs were prepared using (NH4)2SO4 (40% w/v) as precipitant agent and glutaraldehyde (40 mM) as cross-linker, at pH 9, 20 °C. A U10(56) uniform design was used to optimize CLEA production, varying protein concentration, ammonium sulfate %, pH, glutaraldehyde concentration, temperature, and incubation time. The synthesized CLEAs were also analyzed using scanning electron microscopy (SEM) that showed individual particles of <1 µm grouped to form a superstructure. The cross-linked aggregates showed a maximum mass activity of 7750 U/g at 40 °C and pH 8 and retained more than 20% activity at 100 °C. Greater thermostability, resistance to alkaline conditions and the presence of organic solvents, and better durability during storage were observed for LipMatCCR11-CLEAs in comparison with the soluble enzyme. LipMatCCR11-CLEAs presented good reusability by conserving 40% of their initial activity after 9 cycles of reuse.


Assuntos
Proteínas de Bactérias/química , Geobacillus/enzimologia , Lipase/química , Agregados Proteicos , Proteínas de Bactérias/genética , Reagentes de Ligações Cruzadas/química , Estabilidade Enzimática , Geobacillus/genética , Lipase/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
18.
J Cell Sci ; 131(11)2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29724915

RESUMO

Alzheimer disease (AD) pathology includes the accumulation of poly-ubiquitylated (also known as poly-ubiquitinated) proteins and failures in proteasome-dependent degradation. Whereas the distribution of proteasomes and its role in synaptic function have been studied, whether proteasome activity regulates the axonal transport and metabolism of the amyloid precursor protein (APP), remains elusive. By using live imaging in primary hippocampal neurons, we showed that proteasome inhibition rapidly and severely impairs the axonal transport of APP. Fluorescence cross-correlation analyses and membrane internalization blockage experiments showed that plasma membrane APP does not contribute to transport defects. Moreover, by western blotting and double-color APP imaging, we demonstrated that proteasome inhibition precludes APP axonal transport by enhancing its endo-lysosomal delivery, where ß-cleavage is induced. Taken together, we found that proteasomes control the distal transport of APP and can re-distribute Golgi-derived vesicles to the endo-lysosomal pathway. This crosstalk between proteasomes and lysosomes regulates the intracellular APP dynamics, and defects in proteasome activity can be considered a contributing factor that leads to abnormal APP metabolism in AD.This article has an associated First Person interview with the first author of the paper.


Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Axônios/metabolismo , Lisossomos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Transporte Axonal , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Lisossomos/genética , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Complexo de Endopeptidases do Proteassoma/genética
19.
Genet Med ; 22(5): 878-888, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31949314

RESUMO

PURPOSE: Determination of genotypic/phenotypic features of GATAD2B-associated neurodevelopmental disorder (GAND). METHODS: Fifty GAND subjects were evaluated to determine consistent genotypic/phenotypic features. Immunoprecipitation assays utilizing in vitro transcription-translation products were used to evaluate GATAD2B missense variants' ability to interact with binding partners within the nucleosome remodeling and deacetylase (NuRD) complex. RESULTS: Subjects had clinical findings that included macrocephaly, hypotonia, intellectual disability, neonatal feeding issues, polyhydramnios, apraxia of speech, epilepsy, and bicuspid aortic valves. Forty-one novelGATAD2B variants were identified with multiple variant types (nonsense, truncating frameshift, splice-site variants, deletions, and missense). Seven subjects were identified with missense variants that localized within two conserved region domains (CR1 or CR2) of the GATAD2B protein. Immunoprecipitation assays revealed several of these missense variants disrupted GATAD2B interactions with its NuRD complex binding partners. CONCLUSIONS: A consistent GAND phenotype was caused by a range of genetic variants in GATAD2B that include loss-of-function and missense subtypes. Missense variants were present in conserved region domains that disrupted assembly of NuRD complex proteins. GAND's clinical phenotype had substantial clinical overlap with other disorders associated with the NuRD complex that involve CHD3 and CHD4, with clinical features of hypotonia, intellectual disability, cardiac defects, childhood apraxia of speech, and macrocephaly.


Assuntos
Deficiência Intelectual , Megalencefalia , Transtornos do Neurodesenvolvimento , Criança , Feminino , Fatores de Transcrição GATA/genética , Humanos , Deficiência Intelectual/genética , Transtornos do Neurodesenvolvimento/genética , Nucleossomos , Fenótipo , Gravidez , Proteínas Repressoras
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