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1.
J Pediatr Psychol ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38872286

RESUMO

OBJECTIVE: Community-based video interventions offer an effective and potentially scalable early interaction coaching tool for caregivers living in low resource settings. We tested the Universal Baby (UB) video innovation; an early interaction coaching tool using video sourced and produced locally with early child development (ECD) expert supervision. METHODS: This proof-of-concept study enrolled 40 caregivers of children ages 10-18 months assigned to intervention and control groups by health establishments in Carabayllo, Lima, Peru. Mother/child dyads received 12 weekly group health education sessions with social support. Of those, 16 caregivers also received 6 UB videos featuring brain science education and local clips of responsive, reciprocal interaction, also known as "serve and return" interaction. Survey data assessed feasibility and acceptability of the intervention. We assessed improved quality of mother/child interaction using the Parenting Interactions with Children: Checklist of Observations Linked to Outcomes (PICCOLO). RESULTS: We found the program feasible. We successfully trained the local team to produce UB videos using locally-sourced footage and delivered the videos as part of a community-based intervention. We also found it to be acceptable in that participants enthusiastically received the UB videos, reporting they enjoyed being videotaped, and learned how to recognize and appropriately respond to their child's nuanced sounds and gestures. The median change in total PICCOLO scores favored the intervention group compared to the control group. CONCLUSIONS: UB offers great potential as a sustainable, potentially scalable, and culturally appropriate tool to promote equity for child development among young children living in low resource homes globally.

2.
Mol Cell Neurosci ; 124: 103795, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36436725

RESUMO

Properly working synapses are one important guarantor for a functional and healthy brain. They are small, densely packed structures, where information is transmitted through the release of neurotransmitters from synaptic vesicles (SVs). The latter cycle within the presynaptic terminal as they first fuse with the plasma membrane to deliver their neurotransmitter, and afterwards become recycled and prepared for a new release event. The synapse is an autonomous structure functioning mostly independent of the neuronal soma. Dysfunction in synaptic processes associated with local insults or genetic abnormalities can directly compromise synapse function and integrity and subsequently lead to the onset of neurodegenerative diseases. Therefore, measures need to be in place counteracting these threats for instance through the continuous replacement of old and damaged SV proteins. Interestingly recent studies show that the presynaptic scaffolding protein Piccolo contributes to health, function and integrity of synapses, as it mediates the delivery of synaptic proteins from the trans-Golgi network (TGN) towards synapses, as well as the local recycling and turnover of SV proteins within synaptic terminals. It can fulfill these various tasks through its multi-domain structure and ability to interact with numerous binding partners. In addition, Piccolo has recently been linked with the early onset neurodegenerative disease Pontocerebellar Hypoplasia Type 3 (PCH3) further underlying its importance for neuronal health. In this review, we will focus on Piccolo's contributions to synapse function, health and integrity and make a connection how those may contribute to the disease pattern of PCH3.


Assuntos
Doenças Neurodegenerativas , Vesículas Sinápticas , Humanos , Vesículas Sinápticas/metabolismo , Doenças Neurodegenerativas/metabolismo , Sinapses/metabolismo , Terminações Pré-Sinápticas/metabolismo , Transporte Biológico
3.
Cardiol Young ; 34(1): 157-162, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37283091

RESUMO

In this multi-centre study, the mid- to long-term efficacy and safety of the Amplatzer Piccolo Occluder in patent ductus arteriosus closure in premature and term infants as well as children were discussed. Methods. Between 2016 and 2021, 645 patients, 152 of whom were less than 1 month old, underwent ductus closure with the Piccolo device from five different centres in Turkey. The median age of the patients was 2.2 years, and the mean narrowest point of duct diameter was 1.8 mm. Sixty-two patients weighed ≤ 1.5 kg, 90 patients 1.5-3 kg, and the mean follow-up was 20.4 months. In 396, the duct was closed by the retrograde route. Ductal anatomy was Type A in 285, C in 72, E in 171, and F in 64 patients. Fluoroscopy duration was 6.2 min. The procedure success rate was 99.1%. Device embolisation occurred in 13 patients (2%), and 11 were retrieved with a snare. Cardiac perforation and death developed in one premature baby. The left pulmonary artery and the descending aorta stenosis were observed in 3 (0.4%) and in 5 patients (0.5%). Results. Piccolo device is safe and effective in closing ductus in all age groups. It has low profile for use in premature and newborn babies, a small embolisation risk, and a low residual shunt rate after closure. Conclusion. The Piccolo device can be considered as close an ideal occluder. The lower profile, smaller delivery catheter size, and symmetry of this device allow for a venous or arterial approach.


Assuntos
Permeabilidade do Canal Arterial , Nascimento Prematuro , Dispositivo para Oclusão Septal , Criança , Lactente , Recém-Nascido , Feminino , Humanos , Adolescente , Pré-Escolar , Resultado do Tratamento , Permeabilidade do Canal Arterial/cirurgia , Cateterismo Cardíaco/métodos , Recém-Nascido Prematuro
4.
Neurobiol Dis ; 186: 106280, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37666363

RESUMO

Considerable evidence of reactive oxygen species (ROS) involvement in cochlear hair cell (HC) loss, leading to acquired sensorineural hearing loss (SNHL), were reported. Cochlear synaptopathy between HCs and spiral ganglion neurons has been gathering attention as a cochlear HC loss precursor not detectable by normal auditory evaluation. However, the molecular mechanisms linking ROS with HC loss, as well as the relationship between ROS and cochlear synaptopathy have not been elucidated. Here, we examined these linkages using NOX4-TG mice, which constitutively produce ROS without stimulation. mRNA levels of Piccolo 1, a major component of the synaptic ribbon (a specialized structure surrounded by synaptic vesicles in HCs), were decreased in postnatal day 6 NOX4-TG mice cochleae compared to those in WT mice; they were also decreased by noise exposure in 2-week-old WT cochleae. As noise exposure induces ROS production, this suggests that the synaptic ribbon is a target of ROS. The level of CtBP2, another synaptic ribbon component, was significantly lower in NOX4-TG cochleae of 1-month-old and 4-month-old mice compared to that in WT mice, although no significant differences were noted at 1.5- and 2-months. The decrease in CtBP2 plateaued in 4-month-old NOX4-TG, while it gradually decreased from 1 to 6 months in WT mice. Furthermore, CtBP2 level in 2-month-old NOX4-TG mice decreased significantly after exposure to cisplatin and noise compared to that in WT mice. These findings suggest that ROS lead to developmental delays and early degeneration of synaptic ribbons, which could be potential targets for novel therapeutics for ROS-induced SNHL.


Assuntos
Perda Auditiva Neurossensorial , Sinapses , Animais , Camundongos , Espécies Reativas de Oxigênio , Vesículas Sinápticas , Citoesqueleto , Fatores de Transcrição , Perda Auditiva Neurossensorial/induzido quimicamente , Perda Auditiva Neurossensorial/genética
5.
Neurochem Res ; 47(9): 2856-2864, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35906352

RESUMO

Methamphetamine (METH), the most widely distributed psychostimulant, aberrantly activates the reward system in the brain to induce addictive behaviors. The presynaptic protein "Piccolo", encoded by Pclo, was identified as a METH-responsive protein with enhanced expression in the nucleus accumbens (NAc) in mice. Although the physiological and pathological significance of Piccolo has been identified in dopaminergic signaling, its role in METH-induced behavioral abnormalities and the underlying mechanisms remain unclear. To clarify such functions, mice with Piccolo knockdown in the NAc (NAc-miPiccolo mice) by local injection of an adeno-associated virus vector carrying miRNA targeting Pclo were generated and investigated. NAc-miPiccolo mice exhibited suppressed hyperlocomotion, sensitization, and conditioned place preference behavior induced by systemic administration of METH. The excessive release of dopamine in the NAc was reduced in NAc-miPiccolo mice at baseline and in response to METH. These results suggest that Piccolo in the NAc is involved in METH-induced behavioral alterations and is a candidate therapeutic target for the treatment of drug addiction.


Assuntos
Estimulantes do Sistema Nervoso Central , Metanfetamina , Animais , Estimulantes do Sistema Nervoso Central/farmacologia , Dopamina/metabolismo , Metanfetamina/farmacologia , Camundongos , Núcleo Accumbens/metabolismo , Recompensa
6.
Cardiol Young ; 32(8): 1353-1356, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35199639

RESUMO

We present the case of a 4-month-old, former 23-week premature baby who underwent patent ductus arteriosus device closure in the cardiac catheterisation lab with an Amplatzer Piccolo™ device at 12 weeks of life. This was complicated by late migration of the device into the aorta resulting in severe obstruction and requiring surgical intervention.


Assuntos
Permeabilidade do Canal Arterial , Dispositivo para Oclusão Septal , Aorta , Cateterismo Cardíaco/métodos , Permeabilidade do Canal Arterial/cirurgia , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Dispositivo para Oclusão Septal/efeitos adversos , Resultado do Tratamento
7.
Cardiol Young ; 32(3): 503-505, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34378501

RESUMO

Neonatal aortic thrombus is a rare and critical condition that can present mimicking severe coarctation of the aorta or interrupted aortic arch. Transcatheter thrombectomy for this lesion has not been well described. We report a premature neonate with an occlusive proximal descending aorta thrombus, who underwent transcatheter mechanical thrombectomy using an Amplatzer Piccolo PDA occluder (Abbott, North Chicago, IL, USA). The procedure was successful with no subsequent distal thromboembolic events.


Assuntos
Coartação Aórtica , Permeabilidade do Canal Arterial , Dispositivo para Oclusão Septal , Tromboembolia , Trombose , Cateterismo Cardíaco , Permeabilidade do Canal Arterial/cirurgia , Humanos , Recém-Nascido , Trombectomia/métodos , Trombose/diagnóstico por imagem , Trombose/cirurgia , Resultado do Tratamento
8.
J Neurosci ; 40(14): 2943-2959, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122952

RESUMO

Piccolo, a presynaptic active zone protein, is best known for its role in the regulated assembly and function of vertebrate synapses. Genetic studies suggest a further link to several psychiatric disorders as well as Pontocerebellar Hypoplasia type 3 (PCH3). We have characterized recently generated Piccolo KO (Pclogt/gt ) rats. Analysis of rats of both sexes revealed a dramatic reduction in brain size compared with WT (Pclowt/wt ) animals, attributed to a decrease in the size of the cerebral cortical, cerebellar, and pontine regions. Analysis of the cerebellum and brainstem revealed a reduced granule cell layer and a reduction in size of pontine nuclei. Moreover, the maturation of mossy fiber afferents from pontine neurons and the expression of the α6 GABAA receptor subunit at the mossy fiber-granule cell synapse are perturbed, as well as the innervation of Purkinje cells by cerebellar climbing fibers. Ultrastructural and functional studies revealed a reduced size of mossy fiber boutons, with fewer synaptic vesicles and altered synaptic transmission. These data imply that Piccolo is required for the normal development, maturation, and function of neuronal networks formed between the brainstem and cerebellum. Consistently, behavioral studies demonstrated that adult Pclogt/gt rats display impaired motor coordination, despite adequate performance in tasks that reflect muscle strength and locomotion. Together, these data suggest that loss of Piccolo function in patients with PCH3 could be involved in many of the observed anatomical and behavioral symptoms, and that the further analysis of these animals could provide fundamental mechanistic insights into this devastating disorder.SIGNIFICANCE STATEMENT Pontocerebellar Hypoplasia Type 3 is a devastating developmental disorder associated with severe developmental delay, progressive microcephaly with brachycephaly, optic atrophy, seizures, and hypertonia with hyperreflexia. Recent genetic studies have identified non-sense mutations in the coding region of the PCLO gene, suggesting a functional link between this disorder and the presynaptic active zone. Our analysis of Piccolo KO rats supports this hypothesis, formally demonstrating that anatomical and behavioral phenotypes seen in patients with Pontocerebellar Hypoplasia Type 3 are also exhibited by these Piccolo deficient animals.


Assuntos
Cerebelo/metabolismo , Cerebelo/patologia , Cerebelo/fisiopatologia , Proteínas do Citoesqueleto/metabolismo , Neuropeptídeos/metabolismo , Atrofias Olivopontocerebelares , Animais , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Masculino , Fenótipo , Ratos
9.
J Biol Chem ; 295(46): 15482-15497, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-32878983

RESUMO

In Saccharomyces cerevisiae, the Pif1 helicase functions in both nuclear and mitochondrial DNA replication and repair processes, preferentially unwinding RNA:DNA hybrids and resolving G-quadruplex structures. We sought to determine how the various activities of Pif1 are regulated in vivo Here, we report lysine acetylation of nuclear Pif1 and demonstrate that it influences both Pif1's cellular roles and core biochemical activities. Using Pif1 overexpression toxicity assays, we determined that the acetyltransferase NuA4 and deacetylase Rpd3 are primarily responsible for the dynamic acetylation of nuclear Pif1. MS analysis revealed that Pif1 was modified in several domains throughout the protein's sequence on the N terminus (Lys-118 and Lys-129), helicase domain (Lys-525, Lys-639, and Lys-725), and C terminus (Lys-800). Acetylation of Pif1 exacerbated its overexpression toxicity phenotype, which was alleviated upon deletion of its N terminus. Biochemical assays demonstrated that acetylation of Pif1 stimulated its helicase, ATPase, and DNA-binding activities, whereas maintaining its substrate preferences. Limited proteolysis assays indicate that acetylation of Pif1 induces a conformational change that may account for its altered enzymatic properties. We propose that acetylation is involved in regulating of Pif1 activities, influencing a multitude of DNA transactions vital to the maintenance of genome integrity.


Assuntos
Núcleo Celular/metabolismo , DNA Helicases/metabolismo , Lisina/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Acetilação , DNA Helicases/química , DNA Helicases/genética , DNA Fúngico/metabolismo , Histona Acetiltransferases/química , Histona Acetiltransferases/metabolismo , Histona Desacetilases/metabolismo , Mutagênese Sítio-Dirigida , Domínios Proteicos , RNA Fúngico/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Especificidade por Substrato , Espectrometria de Massas em Tandem
10.
Pediatr Cardiol ; 42(6): 1258-1274, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34195869

RESUMO

Transcatheter closure of patent ductus arteriosus (PDA) in premature infants is a feasible, safe, and an effective alternative to surgical ligation and may be performed with an implant success rate of 97%. Major procedural complications related to transcatheter PDA closure in extremely low birth weight (ELBW) infants are relatively infrequent (< 3%) ,but may be associated with a fatality if not optimally managed. Operators performing transcatheter PDA closures should be knowledgeable about these potential complications and management options. Prompt recognition and treatment are often necessary to avoid serious consequences. With strict guidelines on operator training, proctoring requirements, and technical refinements, transcatheter PDA closure in ELBW infants can be performed safely with low complication rates. This article summarizes the consensus guidelines put forward by a panel of physicians for the prevention and management of periprocedural complications of transcatheter PDA closure with the Amplatzer Piccolo Occluder in ELBW infants.


Assuntos
Consenso , Permeabilidade do Canal Arterial/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Guias de Prática Clínica como Assunto , Dispositivo para Oclusão Septal/efeitos adversos , Humanos , Lactente , Recém-Nascido de Peso Extremamente Baixo ao Nascer
11.
J Biol Chem ; 294(52): 20122-20134, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31699900

RESUMO

Histone post-translational modifications (PTMs) are critical for processes such as transcription. The more notable among these are the nonacetyl histone lysine acylation modifications such as crotonylation, butyrylation, and succinylation. However, the biological relevance of these PTMs is not fully understood because their regulation is largely unknown. Here, we set out to investigate whether the main histone acetyltransferases in budding yeast, Gcn5 and Esa1, possess crotonyltransferase activity. In vitro studies revealed that the Gcn5-Ada2-Ada3 (ADA) and Esa1-Yng2-Epl1 (Piccolo NuA4) histone acetyltransferase complexes have the capacity to crotonylate histones. Mass spectrometry analysis revealed that ADA and Piccolo NuA4 crotonylate lysines in the N-terminal tails of histone H3 and H4, respectively. Functionally, we show that crotonylation selectively affects gene transcription in vivo in a manner dependent on Gcn5 and Esa1. Thus, we identify the Gcn5- and Esa1-containing ADA and Piccolo NuA4 complexes as bona fide crotonyltransferases that promote crotonylation-dependent transcription.


Assuntos
Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Crotonatos/química , Histona Acetiltransferases/genética , Histonas/química , Lisina/química , Lisina/metabolismo , Espectrometria de Massas , Peptídeos/análise , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica
12.
J Cell Sci ; 131(15)2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29930086

RESUMO

Hedgehog (Hh) transduces signals by promoting cell surface accumulation and activation of the G-protein-coupled receptor (GPCR)-family protein Smoothened (Smo) in Drosophila, but the molecular mechanism underlying the regulation of Smo trafficking remains poorly understood. Here, we identified the Cul4-DDB1 E3 ubiquitin ligase complex as being essential for Smo ubiquitylation and cell surface clearance. We found that the C-terminal intracellular domain of Smo recruits Cul4-DDB1 through the ß subunit of trimeric G protein (Gß), and that Cul4-DDB1-Gß promotes the ubiquitylation of both Smo and its binding partner G-protein-coupled-receptor kinase 2 (Gprk2) and induces the internalization and degradation of Smo. Hh dissociates Cul4-DDB1 from Smo by recruiting the catalytic subunit of protein kinase A (PKA) to phosphorylate DDB1, which disrupts its interaction with Gß. Inactivation of the Cul4-DDB1 complex resulted in elevated Smo cell surface expression, whereas an excessive amount of Cul4-DDB1 blocked Smo accumulation and attenuated Hh pathway activation. Taken together, our study identifies an E3 ubiquitin ligase complex targeting Smo for ubiquitylation and provides new insight into how Hh signaling regulates Smo trafficking and cell surface expression.


Assuntos
Proteínas Culina/metabolismo , Proteínas de Drosophila/metabolismo , Transdução de Sinais/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/fisiologia , Animais , Proteínas Culina/genética , Proteínas de Drosophila/genética , Ouriços/genética , Ouriços/metabolismo , Ligação Proteica , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética
13.
Catheter Cardiovasc Interv ; 96(6): 1266-1276, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32433821

RESUMO

OBJECTIVES: Characterize the safety and effectiveness of the Amplatzer Piccolo Occluder for patent ductus arteriosus (PDA) closure. BACKGROUND: The presence of a hemodynamically significant PDA has been associated with an increased risk of morbidity and mortality in children born premature. METHODS: This was a single arm, prospective, multicenter, non-randomized study to evaluate the Amplatzer Piccolo Occluder to treat PDA in patients ≥700 g. From June 2017 to February 2019, 200 patients were enrolled at nine centers, with 100 patients weighing ≤2 kg. Primary effectiveness endpoint was the rate of PDA closure at 6-month follow-up. Primary safety endpoint was the rate of major complications through 6 months. Secondary endpoint was rate of significant pulmonary or aortic obstruction through 6 months' follow-up. RESULTS: The implant success rate was 95.5% (191/200) overall and 99% in patients ≤2 kg (99/100). The primary effectiveness endpoint was achieved in 99.4% of implanted patients. Four patients experienced a primary safety endpoint event (2 transfusions, 1 hemolysis, and 1 aortic obstruction). There were no branch pulmonary artery obstructions. Five patients, all ≤2 kg, were noted to have worsening of tricuspid regurgitation (TR) after the procedure. None of the TR incidences manifested clinically. The Amplatzer Piccolo Occluder received FDA approval in January 2019 and became the first device approved for PDA closure in patients ≥700 g. CONCLUSIONS: This study supports the safety and effectiveness of the Amplatzer Piccolo Occluder, particularly in patients between 700 g and 2 kg where there is currently a significant unmet need in the United States. ClinicalTrials.gov identifier: NCT03055858.


Assuntos
Cateterismo Cardíaco/instrumentação , Permeabilidade do Canal Arterial/terapia , Lactente Extremamente Prematuro , Recém-Nascido de muito Baixo Peso , Dispositivo para Oclusão Septal , Peso ao Nascer , Cateterismo Cardíaco/efeitos adversos , Circulação Coronária , Permeabilidade do Canal Arterial/diagnóstico por imagem , Permeabilidade do Canal Arterial/fisiopatologia , Feminino , Idade Gestacional , Hemodinâmica , Humanos , Recém-Nascido , Masculino , Estudos Prospectivos , Desenho de Prótese , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
14.
Sensors (Basel) ; 19(3)2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30678031

RESUMO

There is an increasing interest in using hyperspectral data for phenotyping and crop management while overcoming the challenge of changing atmospheric conditions. The Piccolo dual field-of-view system collects up- and downwelling radiation nearly simultaneously with one spectrometer. Such systems offer great promise for crop monitoring under highly variable atmospheric conditions. Here, the system's utility from a tractor-mounted boom was demonstrated for a case study of estimating soybean plant populations in early vegetative stages. The Piccolo system is described and its performance under changing sky conditions are assessed for two replicates of the same experiment. Plant population assessment was estimated by partial least squares regression (PLSR) resulting in stable estimations by models calibrated and validated under sunny and cloudy or cloudy and sunny conditions, respectively. We conclude that the Piccolo system is effective for data collection under variable atmospheric conditions, and we show its feasibility of operation for precision agriculture research and potential commercial applications.


Assuntos
Glycine max/metabolismo , Análise dos Mínimos Quadrados , Glycine max/genética
15.
J Neurosci ; 37(33): 7848-7863, 2017 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-28701482

RESUMO

RAB3A-interacting molecule (RIM) proteins are important regulators of transmitter release from active zones. At conventional chemical synapses, RIMs contribute substantially to vesicle priming and docking and their loss reduces the readily releasable pool of synaptic vesicles by up to 75%. The priming function of RIMs is mediated via the formation of a tripartite complex with Munc13 and RAB3A, which brings synaptic vesicles in close proximity to Ca2+ channels and the fusion site and activates Munc13. We reported previously that, at mouse photoreceptor ribbon synapses, vesicle priming is Munc13 independent. In this study, we examined RIM expression, distribution, and function at male and female mouse photoreceptor ribbon synapses. We provide evidence that RIM1α and RIM1ß are highly likely absent from mouse photoreceptors and that RIM2α is the major large RIM isoform present at photoreceptor ribbon synapses. We show that mouse photoreceptors predominantly express RIM2 variants that lack the interaction domain for Munc13. Loss of full-length RIM2α in a RIM2α mutant mouse only marginally perturbs photoreceptor synaptic transmission. Our findings therefore strongly argue for a priming mechanism at the photoreceptor ribbon synapse that is independent of the formation of a RIM-Munc13-RAB3A complex and thus provide further evidence for a fundamental difference between photoreceptor ribbon synapses and conventional chemical synapses in synaptic vesicle exocytosis.SIGNIFICANCE STATEMENT RAB3A-interacting molecules 1 and 2 (RIM1/2) are essential regulators of exocytosis. At conventional chemical synapses, their function involves Ca2+ channel clustering and synaptic vesicle priming and docking through interactions with Munc13 and RAB3A, respectively. Examining wild-type and RIM2 mutant mice, we show here that the sensory photoreceptor ribbon synapses most likely lack RIM1 and predominantly express RIM2 variants that lack the interaction domain for Munc13. Our findings demonstrate that the photoreceptor-specific RIM variants are not essential for synaptic vesicle priming at photoreceptor ribbon synapses, which represents a fundamental difference between photoreceptor ribbon synapses and conventional chemical synapses with respect to synaptic vesicle priming mechanisms.


Assuntos
Proteínas de Ligação ao GTP/biossíntese , Células Fotorreceptoras de Vertebrados/metabolismo , Sinapses/metabolismo , Animais , Células Cultivadas , Feminino , Proteínas de Ligação ao GTP/análise , Proteínas de Ligação ao GTP/genética , Expressão Gênica , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células NIH 3T3 , Células Fotorreceptoras de Vertebrados/química , Sinapses/química , Sinapses/genética
16.
J Pediatr ; 202: 171-178.e3, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30268401

RESUMO

OBJECTIVE: We sought to assess worldwide differences among pediatric patients undergoing hemodialysis. Because practices differ widely regarding nutritional resources, treatment practice, and access to renal replacement therapy, investigators from the Pediatric Investigation and Close Collaboration to examine Ongoing Life Outcomes, the pediatric subset of the MONitoring Dialysis Outcomes Cohort (PICCOLO MONDO) performed this cross-sectional study. We hypothesized that growth would be better in developed countries, possibly at the expense of bone mineral disease. STUDY DESIGN: In this cross-sectional study, we analyzed growth by height z score and recommended age-specific bone mineral metabolism markers from 225 patients <18 years of age maintained on hemodialysis, between the years of 2000 to 2012 from 21 countries in different regions. RESULTS: The patients' median age was 16 (IQR 14-17) years, and 45% were females. A height z score less than the third percentile was noted in 34% of the cohort, whereas >66% of patients reported normal heights, with patients from North America having the greatest proportion (>80%). More than 70% of the entire cohort had greater than the age-recommended levels of phosphorus, particularly in the Asia-Pacific and North America, where we also observed the greatest body mass index z score (0.99 ± 1.6) and parathyroid hormone levels (557.1 [268.4-740.5]). Below-recommended parathyroid hormone levels were noted in 26% and elevated levels in 61% of the entire sample, particularly in the Asia Pacific region. Lower-than-recommended calcium levels were noted in 36% of the entire cohort, particularly in Latin America. CONCLUSIONS: We found regional differences in growth- and age-adjusted bone mineral metabolism markers. Children from North America had the best growth, received the most dialysis, but also had the worst phosphate control and body mass index z scores.


Assuntos
Estatura , Doenças Ósseas Metabólicas/epidemiologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/epidemiologia , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/terapia , Diálise Renal/métodos , Adolescente , Antropometria , Biomarcadores/sangue , Índice de Massa Corporal , Doenças Ósseas Metabólicas/diagnóstico , Criança , Pré-Escolar , Distúrbio Mineral e Ósseo na Doença Renal Crônica/diagnóstico , Estudos Transversais , Feminino , Saúde Global , Humanos , Internacionalidade , Falência Renal Crônica/diagnóstico , Masculino , Prognóstico , Medição de Risco , Taxa de Sobrevida
17.
Biochem J ; 472(2): 239-48, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26420880

RESUMO

We have a limited understanding of the site specificity of multi-subunit lysine acetyltransferase (KAT) complexes for histone-based substrates, especially in regards to the different complexes formed during nucleosome assembly. Histone complexes could be a major factor in determining the acetylation specificity of KATs. In the present study, we utilized a label-free quantitative MS-based method to determine the site specificity of acetylation catalysed by Piccolo NuA4 on (H3/H4)2 tetramer, tetramer bound DNA (tetrasome) and nucleosome core particle (NCP). Our results show that Piccolo NuA4 can acetylate multiple lysine residues on these three histone complexes, of which NCP is the most favourable, (H3/H4)2 tetramer is the second and tetrasome is the least favourable substrate for Piccolo NuA4 acetylation. Although Piccolo NuA4 preferentially acetylates histone H4 (H4K12), the site specificity of the enzyme is altered with different histone complex substrates. Our results show that before nucleosome assembly is complete, H3K14 specificity is almost equal to that of H4K12 and DNA-histone interactions suppress the acetylation ability of Piccolo NuA4. These data suggest that the H2A/H2B dimer could play a critical role in the increase in acetylation specificity of Piccolo NuA4 for NCP. This demonstrates that histone complex formation can alter the acetylation preference of Piccolo NuA4. Such findings provide valuable insight into regulating Piccolo NuA4 specificity by modulating chromatin dynamics and in turn manipulating gene expression.


Assuntos
Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Nucleossomos/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Xenopus/metabolismo , Acetilcoenzima A/metabolismo , Acetilação , Acetiltransferases , Animais , Montagem e Desmontagem da Cromatina , Histona Acetiltransferases/química , Histona Acetiltransferases/genética , Histonas/química , Histonas/genética , Cinética , Lisina/metabolismo , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Nucleossomos/química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Estrutura Quaternária de Proteína , Subunidades Proteicas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Especificidade por Substrato , Proteínas de Xenopus/química , Proteínas de Xenopus/genética
19.
Front Pediatr ; 12: 1257694, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38379909

RESUMO

The patent ductus arteriosus frequently poses a significant morbidity in preterm infants, subjecting their immature pulmonary vascular bed to substantial volume overload. This, in turn, results in concurrent hypoperfusion to post-ductal organs, and subsequently alters cerebral blood flow. In addition, treatment has not demonstrated definitive improvements in patient outcomes. Currently, the optimal approach remains a subject of considerable debate with ongoing research controversy regarding the best approach. This article provides a comprehensive review of existing literature.

20.
J Soc Cardiovasc Angiogr Interv ; 3(2): 101194, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39132219

RESUMO

Background: Device closure of a patent ductus arteriosus (PDA) is rapidly evolving, with the Amplatzer Piccolo Occluder (Abbott) receiving US Food and Drug Administration approval and becoming the first device approved for PDA closure in patients ≥700 g. We report on the first known cases of complete left pulmonary artery (LPA) occlusion following Piccolo closure of a PDA in premature infants. Methods: Retrospective chart analysis of PDA closures. Results: We have performed over 50 cases of Piccolo device closure of the PDA in preterm neonates in the past 2 years, with these 2 cases representing our only complications (4%). This represents a total complication rate similar to or lower than most centers that have published data for this procedure. Conclusions: Although rare, severe LPA obstruction can be seen in premature infants following device closure of the PDA. The Piccolo device is designed to ideally remain entirely intraductal. Although our device selection appeared to provide a device short enough for the given ductal length, we recommend, whenever possible, giving consideration to using the shortest possible device. We also recommend increasing the frequency of echocardiographic surveillance to weekly studies if at any time the imaging demonstrates an increase in the degree of obstruction/turbulence.

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