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1.
Cell ; 166(2): 343-357, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27374334

RESUMO

Cells benefit from silencing foreign genetic elements but must simultaneously avoid inactivating endogenous genes. Although chromatin modifications and RNAs contribute to maintenance of silenced states, the establishment of silenced regions will inevitably reflect underlying DNA sequence and/or structure. Here, we demonstrate that a pervasive non-coding DNA feature in Caenorhabditis elegans, characterized by 10-base pair periodic An/Tn-clusters (PATCs), can license transgenes for germline expression within repressive chromatin domains. Transgenes containing natural or synthetic PATCs are resistant to position effect variegation and stochastic silencing in the germline. Among endogenous genes, intron length and PATC-character undergo dramatic changes as orthologs move from active to repressive chromatin over evolutionary time, indicating a dynamic character to the An/Tn periodicity. We propose that PATCs form the basis of a cellular immune system, identifying certain endogenous genes in heterochromatic contexts as privileged while foreign DNA can be suppressed with no requirement for a cellular memory of prior exposure.


Assuntos
Caenorhabditis elegans/metabolismo , DNA Intergênico/metabolismo , Inativação Gênica , Animais , Composição de Bases , Caenorhabditis elegans/genética , Cromatina , Elementos de DNA Transponíveis , DNA Viral/genética , Células Germinativas/metabolismo , Íntrons , Regiões Promotoras Genéticas , RNA Antissenso/metabolismo , RNA Mensageiro/metabolismo , Transgenes
2.
Cell ; 154(2): 337-50, 2013 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-23870123

RESUMO

Synaptic contacts are largely established during embryogenesis and are then maintained during growth. To identify molecules involved in this process, we conducted a forward genetic screen in C. elegans and identified cima-1. In cima-1 mutants, synaptic contacts are correctly established during embryogenesis, but ectopic synapses emerge during postdevelopmental growth. cima-1 encodes a solute carrier in the SLC17 family of transporters that includes sialin, a protein that when mutated in humans results in neurological disorders. cima-1 does not function in neurons but rather functions in the nearby epidermal cells to correctly position glia during postlarval growth. Our findings indicate that CIMA-1 antagonizes the FGF receptor (FGFR), and does so most likely by inhibiting FGFR's role in epidermal-glia adhesion rather than signaling. Our data suggest that epidermal-glia crosstalk, in this case mediated by a transporter and the FGF receptor, is vital to preserve embryonically derived circuit architecture during postdevelopmental growth.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/metabolismo , Neuroglia/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo I/metabolismo , Sinapses , Animais , Tamanho Corporal , Caenorhabditis elegans/embriologia , Proteínas de Caenorhabditis elegans/genética , Desenvolvimento Embrionário , Células Epidérmicas , Epiderme/metabolismo , Mutação , Neuritos/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo I/genética
3.
Cell ; 141(5): 846-58, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20510931

RESUMO

Polarized trafficking of synaptic proteins to axons and dendrites is crucial to neuronal function. Through forward genetic analysis in C. elegans, we identified a cyclin (CYY-1) and a cyclin-dependent Pctaire kinase (PCT-1) necessary for targeting presynaptic components to the axon. Another cyclin-dependent kinase, CDK-5, and its activator p35, act in parallel to and partially redundantly with the CYY-1/PCT-1 pathway. Synaptic vesicles and active zone proteins mostly mislocalize to dendrites in animals defective for both PCT-1 and CDK-5 pathways. Unlike the kinesin-3 motor, unc-104/Kif1a mutant, cyy-1 cdk-5 double mutants have no reduction in anterogradely moving synaptic vesicle precursors (SVPs) as observed by dynamic imaging. Instead, the number of retrogradely moving SVPs is dramatically increased. Furthermore, this mislocalization defect is suppressed by disrupting the retrograde motor, the cytoplasmic dynein complex. Thus, PCT-1 and CDK-5 pathways direct polarized trafficking of presynaptic components by inhibiting dynein-mediated retrograde transport and setting the balance between anterograde and retrograde motors.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Sinapses/metabolismo , Animais , Axônios , Caenorhabditis elegans , Ciclinas/metabolismo , Cinesinas/metabolismo , Neurônios , Transdução de Sinais
4.
PLoS Genet ; 17(11): e1009755, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34748534

RESUMO

Gene editing in C. elegans using plasmid-based CRISPR reagents requires microinjection of many animals to produce a single edit. Germline silencing of plasmid-borne Cas9 is a major cause of inefficient editing. Here, we present a set of C. elegans strains that constitutively express Cas9 in the germline from an integrated transgene. These strains markedly improve the success rate for plasmid-based CRISPR edits. For simple, short homology arm GFP insertions, 50-100% of injected animals typically produce edited progeny, depending on the target locus. Template-guided editing from an extrachromosomal array is maintained over multiple generations. We have built strains with the Cas9 transgene on multiple chromosomes. Additionally, each Cas9 locus also contains a heatshock-driven Cre recombinase for selectable marker removal and a bright fluorescence marker for easy outcrossing. These integrated Cas9 strains greatly reduce the workload for producing individual genome edits.


Assuntos
Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas , Caenorhabditis elegans/genética , Edição de Genes/métodos , Genoma Helmíntico , Animais
5.
Opt Express ; 31(20): 33565-33581, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859135

RESUMO

By engineering the point-spread function (PSF) of single molecules, different fluorophore species can be imaged simultaneously and distinguished by their unique PSF patterns. Here, we insert a silicon-dioxide phase plate at the Fourier plane of the detection path of a wide-field fluorescence microscope to produce distinguishable PSFs (X-PSFs) at different wavelengths. We demonstrate that the resulting PSFs can be localized spatially and spectrally using a maximum-likelihood estimation algorithm and can be utilized for hyper-spectral super-resolution microscopy of biological samples. We produced superresolution images of fixed U2OS cells using X-PSFs for dSTORM imaging with simultaneous illumination of up to three fluorophore species. The species were distinguished only by the PSF pattern. We achieved ∼21-nm lateral localization precision (FWHM) and ∼17-nm axial precision (FWHM) with an average of 1,800 - 3,500 photons per PSF and a background as high as 130 - 400 photons per pixel. The modified PSF distinguished fluorescent probes with ∼80 nm separation between spectral peaks.

6.
Ear Hear ; 44(3): 603-618, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36534639

RESUMO

OBJECTIVES: The purpose of this study was to investigate differences in auditory environments and hearing aid feature activation between younger listeners with normal hearing and older listeners with hearing loss in an urban and rural location. We hypothesized that (1) urban dwellers and younger listeners would encounter more diverse and demanding auditory environments than rural dwellers and older listeners, respectively; (2) the advanced hearing aid features (noise reduction and directional microphone) of urban dwellers and younger listeners would be activated more frequently than rural dwellers and older listeners, respectively. DESIGN: The design of this study was cross-sectional with repeated measures. A total of 12 older adults with hearing loss (OHL-U) and 11 younger adults with normal hearing (YNH-U) were recruited from an urban area (Berkeley, California) and 13 older adults with hearing loss (OHL-R) and 10 YNH-U were recruited from a rural area (Iowa City, Iowa). Participants wore hearing aids that recorded data about their listening environments and completed ecological momentary assessments for 1 week. RESULTS: The YNH-U group experienced higher sound pressure levels and hearing aid features were activated more frequently than in the OHL groups. The OHL-R group experienced significantly less diverse sound pressure levels than the YNH-U group. The YNH-R group had sound levels between the YNH-U group and the OHL groups but without significant differences from any other group. The YNH groups showed a greater likelihood of hearing aid feature activation than the OHL-R group. CONCLUSIONS: Demographics affect auditory environments and the activation of hearing aid features. Younger urban dwellers have the most diverse or demanding auditory environments and hearing aid feature activation, and older, rural dwellers with hearing loss have the least diverse or demanding auditory environments and hearing aid feature activation. Future studies of real-world auditory environments and audiology intervention effectiveness should consider location in recruitment and interpretation of results.


Assuntos
Surdez , Auxiliares de Audição , Perda Auditiva Neurossensorial , Perda Auditiva , Percepção da Fala , Humanos , Idoso , Perda Auditiva Neurossensorial/reabilitação , Estudos Transversais , Percepção da Fala/fisiologia , Perda Auditiva/epidemiologia
7.
J Acoust Soc Am ; 154(6): 3627-3643, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38051522

RESUMO

Hearing aids show more benefit in traditional laboratory speech-in-noise tests than in real-world noisy environments. Real-world noise comprises a large range of acoustic properties that vary randomly and rapidly between and within environments, making quantifying real-world noise and using it in experiments and clinical tests challenging. One approach is to use acoustic features and statistics to quantify acoustic properties of real-world noise and control for them or measure their relationship to listening performance. In this study, the complexity of real-world noise from different environments was quantified using entropy in both the time- and frequency-domains. A distribution of noise segments from low to high entropy were extracted. Using a trial-by-trial design, listeners with normal hearing and hearing loss (in aided and unaided conditions) repeated back sentences embedded in these noise segments. Entropy significantly affected speech perception, with a larger effect of entropy in the time-domain than the frequency-domain, a larger effect for listeners with normal hearing than for listeners with hearing loss, and a larger effect for listeners with hearing loss in the aided than unaided condition. Speech perception also differed between most environment types. Combining entropy with the environment type improved predictions of speech perception above the environment type alone.


Assuntos
Surdez , Auxiliares de Audição , Perda Auditiva Neurossensorial , Perda Auditiva , Percepção da Fala , Humanos , Entropia , Audição , Ruído
8.
Opt Express ; 30(2): 1546-1554, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209312

RESUMO

Deep-brain microscopy is strongly limited by the size of the imaging probe, both in terms of achievable resolution and potential trauma due to surgery. Here, we show that a segment of an ultra-thin multi-mode fiber (cannula) can replace the bulky microscope objective inside the brain. By creating a self-consistent deep neural network that is trained to reconstruct anthropocentric images from the raw signal transported by the cannula, we demonstrate a single-cell resolution (< 10µm), depth sectioning resolution of 40 µm, and field of view of 200 µm, all with green-fluorescent-protein labelled neurons imaged at depths as large as 1.4 mm from the brain surface. Since ground-truth images at these depths are challenging to obtain in vivo, we propose a novel ensemble method that averages the reconstructed images from disparate deep-neural-network architectures. Finally, we demonstrate dynamic imaging of moving GCaMp-labelled C. elegans worms. Our approach dramatically simplifies deep-brain microscopy.


Assuntos
Encéfalo/diagnóstico por imagem , Aprendizado de Máquina , Microscopia de Fluorescência/métodos , Neuroimagem/métodos , Animais , Caenorhabditis elegans/citologia , Células Cultivadas , Proteínas de Fluorescência Verde/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Camundongos , Procedimentos Cirúrgicos Minimamente Invasivos , Redes Neurais de Computação , Neurônios/citologia , Neurônios/metabolismo
9.
Catheter Cardiovasc Interv ; 97(4): E467-E474, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32681717

RESUMO

OBJECTIVES: To ascertain the effect of age on outcomes after culprit-only and complete revascularization after Primary PCI (PPCI) for ST-elevation myocardial infarction (STEMI). BACKGROUND: The numbers of older patients being treated with PPCI are increasing. The optimal management of nonculprit stenoses in such patients is unclear. METHODS: We conducted an analysis of patients aged ≥75 years randomized in the DANAMI-3-PRIMULTI study to either culprit-only or complete FFR-guided revascularization. The primary endpoint was a composite of all-cause mortality, nonfatal reinfarction, and ischaemia-driven revascularization of lesions in noninfarct-related arteries after a median of 27 months of follow-up. RESULTS: One hundred and ten of six hundred and twenty seven patients in the DANAMI-3-PRIMULTI trial were aged ≥75 years. These patients were more likely female (p < .001), hypertensive (p < .001), had lower hemoglobin levels (p < .001), and higher serum creatinine levels (p < .001) than the younger patients in the trial. Other than less use of drug-eluting stents (96.6 versus 88.0%: p = .02), there were no significant differences in procedural technique and success between patients aged <75 years and those ≥75 years of age. There was no significant difference in the incidence of the primary endpoint in patients ≥75 years randomized to culprit-only or FFR-guided complete revascularization (HR 1.49 [95% CI 0.57-4.65]; log-rank p = .19; p for interaction versus patients <75 years <.001). There was a significant interaction between age as a continuous variable, treatment assignment, and the primary outcome (p < .001); beyond the age of about 75 years, there may be no prognostic advantage to complete revascularization. CONCLUSIONS: In patients ≥75 years, after treatment of the culprit lesion in STEMI, there is no significant prognostic benefit to prophylactic complete revascularization of nonculprit stenoses. Pending further study, data would support a symptom-guided approach to further invasive treatment.


Assuntos
Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Feminino , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Prognóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Resultado do Tratamento
10.
Int J Audiol ; 60(5): 328-340, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33074752

RESUMO

OBJECTIVE: Hearing aid technology can allow users to "geo-tag" hearing aid preferences using the Global Positioning System (GPS). This technology assumes that listening environment characteristics that affect hearing aid benefit change little in a location over time. The purpose of this study was to investigate whether certain characteristics (reverberation, signal type, listening activity, noise location, noisiness, talker familiarity, talker location, and visual cues) changed in a location over time. Design: Participants completed GPS-tagged surveys on smartphones to report on characteristics of their listening environments. Coordinates were used to create indices that described how much listening environment characteristics changed in a location over time. Indices computed in one location were compared to indices computed across all locations for each participant. Study sample: 54 adults with hearing loss participated in this study (26 males and 38 females; 30 experienced hearing aid users and 24 new users). Results: A location dependency was observed for all characteristics. Characteristics were significantly different from one another in their stability over time. Conclusions: Listening environment characteristics changed less over time in a given location than in participants' lives generally. The effectiveness of GPS-dependent hearing aid settings likely depends on the accuracy and location definition of the GPS feature.


Assuntos
Auxiliares de Audição , Perda Auditiva Neurossensorial , Percepção da Fala , Adulto , Feminino , Sistemas de Informação Geográfica , Humanos , Masculino , Ruído/efeitos adversos
11.
Appl Environ Microbiol ; 87(1)2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33067198

RESUMO

The high-gamma-amino butyric acid (GABA)-producing bacterium Levilactobacillus brevis strain NPS-QW 145, along with Streptococcus thermophilus (one of the two starter bacteria used to make yogurt for its proteolytic activity), enhances GABA production in milk. However, a mechanistic understanding of how Levilactobacillus brevis cooperates with S. thermophilus to stimulate GABA production has been lacking. Comparative peptidomic and metatranscriptomic analyses were carried out to unravel the casein and lactose utilization patterns during milk fermentation with the coculture. We found that particular peptides hydrolyzed by S. thermophilus ASCC1275 were transported and biodegraded with peptidase in Lb. brevis 145 to meet the growth needs of the latter. In addition, amino acid synthesis and metabolism in Lb. brevis 145 were activated to further support its growth. Glucose, as a result of lactose hydrolysis by S. thermophilus 1275, but not available lactose in milk, was metabolized as the main carbon source by Lb. brevis 145 for ATP production. In the stationary phase, under acidic conditions due to the accumulation of lactic acid produced by S. thermophilus 1275, the expression of genes involved in pyridoxal phosphate (coenzyme of glutamic acid decarboxylase) metabolism and glutamic acid decarboxylase (Gad) in Lb. brevis 145 was induced for GABA production.SIGNIFICANCE A huge market for GABA-rich milk as a dietary therapy for the management of hypertension is anticipated. The novelty of this work lies in applying peptide profiles supported by metatranscriptomics to elucidate (i) the pattern of casein hydrolysis by S. thermophilus 1275, (ii) the supply of peptides and glucose by S. thermophilus 1275 to Lb. brevis 145, (iii) the transportation of peptides in Lb. brevis and the degradation of peptides by this organism, which was reported to be nonproteolytic, and (iv) GABA production by Lb. brevis 145 under acidic conditions. Based on the widely reported contribution of lactic acid bacteria (LAB) and GABA to human health, the elucidation of interactions between the two groups of bacterial communities in the production of GABA-rich milk is important for promoting the development of functional dairy food and may provide new insight into the development of industrial GABA production.


Assuntos
Brevibacillus/metabolismo , Fermentação , Leite/metabolismo , Streptococcus thermophilus/metabolismo , Transcriptoma , Ácido gama-Aminobutírico/metabolismo , Animais , Transporte Biológico , Carbono/metabolismo , Técnicas de Cocultura , Perfilação da Expressão Gênica , Lactose/metabolismo , Proteínas do Leite/metabolismo , Nitrogênio/metabolismo
12.
Nature ; 515(7526): 228-33, 2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25296249

RESUMO

Ultrafast endocytosis can retrieve a single, large endocytic vesicle as fast as 50-100 ms after synaptic vesicle fusion. However, the fate of the large endocytic vesicles is not known. Here we demonstrate that these vesicles transition to a synaptic endosome about one second after stimulation. The endosome is resolved into coated vesicles after 3 s, which in turn become small-diameter synaptic vesicles 5-6 s after stimulation. We disrupted clathrin function using RNA interference (RNAi) and found that clathrin is not required for ultrafast endocytosis but is required to generate synaptic vesicles from the endosome. Ultrafast endocytosis fails when actin polymerization is disrupted, or when neurons are stimulated at room temperature instead of physiological temperature. In the absence of ultrafast endocytosis, synaptic vesicles are retrieved directly from the plasma membrane by clathrin-mediated endocytosis. These results may explain discrepancies among published experiments concerning the role of clathrin in synaptic vesicle endocytosis.


Assuntos
Clatrina/metabolismo , Endossomos/metabolismo , Vesículas Sinápticas/metabolismo , Animais , Membrana Celular/metabolismo , Endocitose , Humanos , Camundongos , Temperatura
13.
J Acoust Soc Am ; 148(2): 908, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32873021

RESUMO

This study investigated the effect of presentation level on spectral-ripple detection for listeners with and without sensorineural hearing loss (SNHL). Participants were 25 listeners with normal hearing and 25 listeners with SNHL. Spectral-ripple detection thresholds (SRDTs) were estimated at three spectral densities (0.5, 2, and 4 ripples per octave, RPO) and three to four sensation levels (SLs) (10, 20, 40, and, when possible, 60 dB SL). Each participant was also tested at 90 dB sound pressure level (SPL). Results indicate that level affected SRDTs. However, the effect of level depended on ripple density and hearing status. For all listeners and all RPO conditions, SRDTs improved from 10 to 40 dB SL. In the 2- and 4-RPO conditions, SRDTs became poorer from the 40 dB SL to the 90 dB SPL condition. The results suggest that audibility likely controls spectral-ripple detection at low SLs for all ripple densities, whereas spectral resolution likely controls spectral-ripple detection at high SLs and ripple densities. For optimal ripple detection across all listeners, clinicians and researchers should use a SL of 40 dB SL. To avoid absolute-level confounds, a presentation level of 80 dB SPL can also be used.


Assuntos
Surdez , Perda Auditiva Neurossensorial , Percepção da Fala , Limiar Auditivo , Audição , Perda Auditiva Neurossensorial/diagnóstico , Humanos
14.
Circulation ; 138(24): 2741-2750, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30565996

RESUMO

BACKGROUND: The optimal timing of invasive coronary angiography (ICA) and revascularization in patients with non-ST-segment elevation acute coronary syndrome is not well defined. We tested the hypothesis that a strategy of very early ICA and possible revascularization within 12 hours of diagnosis is superior to an invasive strategy performed within 48 to 72 hours in terms of clinical outcomes. METHODS: Patients admitted with clinical suspicion of non-ST-segment elevation acute coronary syndrome in the Capital Region of Copenhagen, Denmark, were screened for inclusion in the VERDICT trial (Very Early Versus Deferred Invasive Evaluation Using Computerized Tomography) ( ClinicalTrials.gov NCT02061891). Patients with ECG changes indicating new ischemia or elevated troponin, in whom ICA was clinically indicated and deemed logistically feasible within 12 hours, were randomized 1:1 to ICA within 12 hours or standard invasive care within 48 to 72 hours. The primary end point was a combination of all-cause death, nonfatal recurrent myocardial infarction, hospital admission for refractory myocardial ischemia, or hospital admission for heart failure. RESULTS: A total of 2147 patients were randomized; 1075 patients allocated to very early invasive evaluation had ICA performed at a median of 4.7 hours after randomization, whereas 1072 patients assigned to standard invasive care had ICA performed 61.6 hours after randomization. Among patients with significant coronary artery disease identified by ICA, coronary revascularization was performed in 88.4% (very early ICA) and 83.1% (standard invasive care). Within a median follow-up time of 4.3 (interquartile range, 4.1-4.4) years, the primary end point occurred in 296 (27.5%) of participants in the very early ICA group and 316 (29.5%) in the standard care group (hazard ratio, 0.92; 95% CI, 0.78-1.08). Among patients with a GRACE risk score (Global Registry of Acute Coronary Events) >140, a very early invasive treatment strategy improved the primary outcome compared with the standard invasive treatment (hazard ratio, 0.81; 95% CI, 0.67-1.01; P value for interaction=0.023). CONCLUSIONS: A strategy of very early invasive coronary evaluation does not improve overall long-term clinical outcome compared with an invasive strategy conducted within 2 to 3 days in patients with non-ST-segment elevation acute coronary syndrome. However, in patients with the highest risk, very early invasive therapy improves long-term outcomes. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02061891.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Angiografia Coronária/métodos , Intervenção Coronária Percutânea , Síndrome Coronariana Aguda/terapia , Idoso , Feminino , Parada Cardíaca/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Troponina/metabolismo
15.
J Transl Med ; 17(1): 360, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31711513

RESUMO

BACKGROUND: Stem cell therapy is investigated as a treatment option for patients with ischemic heart disease. In this study, long-term safety and efficacy of autologous intra-myocardial injections of adipose-derived stromal cells (ASCs) was studied in patients with refractory angina. METHODS: Sixty patients with coronary artery stenosis and preserved left ventricular ejection fraction were 2:1 randomised to intramyocardial injections of ASCs or saline and followed for 3 years. RESULTS: For patients in the ASC group, the bicycle exercise time and the exercise performance in watt were un-changed (383 ± 30 s to 370 ± 44 s, P = 0.052 and 81 ± 6 to 78 ± 10, P = 0.123, respectively), but the performance in METs was reduced significantly (4.2 ± 0.3 to 4.0 ± 0.4, P = 0.027) during the follow-up period. However, in the same period, there was in the placebo group a significant decline in bicycle exercise time (437 ± 53 s to 383 ± 58 s, P = 0.001), the exercise performance measured in watt (87 ± 12 W to 80 ± 12 W, P = 0.019) and in METs (4.5 ± 0.4 to 4.1 ± 0.4, P = 0.002). Moreover, angina measured as CCS class was significantly reduced in the ASC group but not in the placebo group (2.5 ± 0.9 to 1.8 ± 1.2, P = 0.002 and 2.5 ± 0.8 to 2.1 ± 1.3, P = 0.186, respectively). However, no significant change was observed between the two groups. CONCLUSIONS: Patients receiving ASCs had improved cardiac symptoms and unchanged exercise capacity, in opposition to deterioration in the placebo group. Trial registration ClinicalTrials.gov Identifier: NCT01449032. Registered 7 October 2011-Retrospectively registered, https://www.clinicaltrials.gov/ct2/show/NCT01449032?term=jens+kastrup&rank=7.


Assuntos
Angina Pectoris/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angina Pectoris/fisiopatologia , Autoenxertos , Técnicas de Cultura de Células , Separação Celular , Método Duplo-Cego , Teste de Esforço , Feminino , Seguimentos , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/terapia , Miocárdio , Gordura Subcutânea/citologia , Pesquisa Translacional Biomédica , Resultado do Tratamento , Função Ventricular Esquerda
16.
Nature ; 504(7479): 242-247, 2013 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-24305055

RESUMO

To sustain neurotransmission, synaptic vesicles and their associated proteins must be recycled locally at synapses. Synaptic vesicles are thought to be regenerated approximately 20 s after fusion by the assembly of clathrin scaffolds or in approximately 1 s by the reversal of fusion pores via 'kiss-and-run' endocytosis. Here we use optogenetics to stimulate cultured hippocampal neurons with a single stimulus, rapidly freeze them after fixed intervals and examine the ultrastructure using electron microscopy--'flash-and-freeze' electron microscopy. Docked vesicles fuse and collapse into the membrane within 30 ms of the stimulus. Compensatory endocytosis occurs within 50 to 100 ms at sites flanking the active zone. Invagination is blocked by inhibition of actin polymerization, and scission is blocked by inhibiting dynamin. Because intact synaptic vesicles are not recovered, this form of recycling is not compatible with kiss-and-run endocytosis; moreover, it is 200-fold faster than clathrin-mediated endocytosis. It is likely that 'ultrafast endocytosis' is specialized to restore the surface area of the membrane rapidly.


Assuntos
Endocitose , Hipocampo/citologia , Sinapses/metabolismo , Actinas/metabolismo , Actinas/ultraestrutura , Potenciais de Ação , Animais , Dinaminas/metabolismo , Dinaminas/ultraestrutura , Exocitose , Fusão de Membrana , Camundongos , Microscopia Eletrônica , Rodopsina/genética , Rodopsina/metabolismo , Sinapses/ultraestrutura , Transmissão Sináptica , Vesículas Sinápticas/metabolismo , Vesículas Sinápticas/ultraestrutura , Fatores de Tempo
17.
Ear Hear ; 40(4): 1001-1008, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30531261

RESUMO

OBJECTIVES: To (1) identify the etiologies and risk factors of the patient cohort and determine the degree to which they reflected the incidence for children with hearing loss and (2) quantify practice management patterns in three catchment areas of the United States with available centers of excellence in pediatric hearing loss. DESIGN: Medical information for 307 children with bilateral, mild-to-severe hearing loss was examined retrospectively. Children were participants in the Outcomes of Children with Hearing Loss (OCHL) study, a 5-year longitudinal study that recruited subjects at three different sites. Children aged 6 months to 7 years at time of OCHL enrollment were participants in this study. Children with cochlear implants, children with severe or profound hearing loss, and children with significant cognitive or motor delays were excluded from the OCHL study and, by extension, from this analysis. Medical information was gathered using medical records and participant intake forms, the latter reflecting a caregiver's report. A comparison group included 134 children with normal hearing. A Chi-square test on two-way tables was used to assess for differences in referral patterns by site for the children who are hard of hearing (CHH). Linear regression was performed on gestational age and birth weight as continuous variables. Risk factors were assessed using t tests. The alpha value was set at p < 0.05. RESULTS: Neonatal intensive care unit stay, mechanical ventilation, oxygen requirement, aminoglycoside exposure, and family history were correlated with hearing loss. For this study cohort, congenital cytomegalovirus, strep positivity, bacterial meningitis, extracorporeal membrane oxygenation, and loop diuretic exposure were not associated with hearing loss. Less than 50% of children underwent imaging, although 34.2% of those scanned had abnormalities identified. No single imaging modality was preferred. Differences in referral rates were apparent for neurology, radiology, genetics, and ophthalmology. CONCLUSIONS: The OCHL cohort reflects known etiologies of CHH. Despite available guidelines, centers of excellence, and high-yield rates for imaging, the medical workup for children with hearing loss remains inconsistently implemented and widely variable. There remains limited awareness as to what constitutes appropriate medical assessment for CHH.


Assuntos
Aminoglicosídeos/uso terapêutico , Perda Auditiva Bilateral/epidemiologia , Hospitalização/estatística & dados numéricos , Encaminhamento e Consulta , Respiração Artificial/estatística & dados numéricos , Estudos de Casos e Controles , Área Programática de Saúde , Criança , Pré-Escolar , Feminino , Genética Médica , Perda Auditiva Bilateral/etiologia , Humanos , Lactente , Unidades de Terapia Intensiva Neonatal , Masculino , Anamnese , Neurologia , Oftalmologia , Oxigenoterapia/estatística & dados numéricos , Radiologia , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Estados Unidos/epidemiologia
18.
PLoS Genet ; 12(1): e1005654, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26771544

RESUMO

The C. elegans AWC olfactory neuron pair communicates to specify asymmetric subtypes AWCOFF and AWCON in a stochastic manner. Intercellular communication between AWC and other neurons in a transient NSY-5 gap junction network antagonizes voltage-activated calcium channels, UNC-2 (CaV2) and EGL-19 (CaV1), in the AWCON cell, but how calcium signaling is downregulated by NSY-5 is only partly understood. Here, we show that voltage- and calcium-activated SLO BK potassium channels mediate gap junction signaling to inhibit calcium pathways for asymmetric AWC differentiation. Activation of vertebrate SLO-1 channels causes transient membrane hyperpolarization, which makes it an important negative feedback system for calcium entry through voltage-activated calcium channels. Consistent with the physiological roles of SLO-1, our genetic results suggest that slo-1 BK channels act downstream of NSY-5 gap junctions to inhibit calcium channel-mediated signaling in the specification of AWCON. We also show for the first time that slo-2 BK channels are important for AWC asymmetry and act redundantly with slo-1 to inhibit calcium signaling. In addition, nsy-5-dependent asymmetric expression of slo-1 and slo-2 in the AWCON neuron is necessary and sufficient for AWC asymmetry. SLO-1 and SLO-2 localize close to UNC-2 and EGL-19 in AWC, suggesting a role of possible functional coupling between SLO BK channels and voltage-activated calcium channels in AWC asymmetry. Furthermore, slo-1 and slo-2 regulate the localization of synaptic markers, UNC-2 and RAB-3, in AWC neurons to control AWC asymmetry. We also identify the requirement of bkip-1, which encodes a previously identified auxiliary subunit of SLO-1, for slo-1 and slo-2 function in AWC asymmetry. Together, these results provide an unprecedented molecular link between gap junctions and calcium pathways for terminal differentiation of olfactory neurons.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Canais de Cálcio/genética , Diferenciação Celular/genética , Junções Comunicantes/genética , Canais de Potássio Ativados por Cálcio de Condutância Alta/genética , Proteínas de Membrana/genética , Proteínas de Membrana Transportadoras/genética , Proteínas Musculares/genética , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/biossíntese , Canais de Cálcio/biossíntese , Sinalização do Cálcio/genética , Comunicação Celular/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Membrana/biossíntese , Proteínas Musculares/biossíntese , Neurônios Receptores Olfatórios/metabolismo , Olfato/genética
19.
Eur Heart J ; 39(2): 102-110, 2018 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-29029035

RESUMO

Aims: We aimed to study survival and causes of death in patients with ST-elevation acute coronary syndrome (STE-ACS) with and without obstructive coronary artery disease (CAD). Methods and results: We included 4793 consecutive patients with STE-ACS triaged for acute coronary angiography at a large cardiac invasive centre (2009-2014). Of these, 88% had obstructive CAD (stenosis ≥50%), 6% had non-obstructive CAD (stenosis 1-49%), and 5% had normal coronary arteries. Patients without obstructive CAD were younger and more often female with fewer cardiovascular risk factors. Median follow-up time was 2.6 years. Compared with patients with obstructive CAD, the short-term hazard of death (≤30 days) was lower in both patients with non-obstructive CAD [hazard ratio (HR) 0.49, 95% confidence interval (CI) 0.27-0.89, P = 0.018] and normal coronary arteries (HR 0.31, 95% CI 0.11-0.83, P = 0.021). In contrast, the long-term hazard of death (>30 days) was similar in patients with non-obstructive CAD (HR 1.15, 95% CI 0.77-1.72, P = 0.487) and higher in patients with normal coronary arteries (HR 2.44, 95% CI 1.58-3.76, P < 0.001), regardless of troponin levels. Causes of death were cardiovascular in 70% of patients with obstructive CAD, 38% with non-obstructive CAD, and 32% with normal coronary arteries. Finally, patients without obstructive CAD had lower survival compared with an age and sex matched general population. Conclusions: STE-ACS patients without obstructive CAD had a long-term risk of death similar to or higher than patients with obstructive CAD. Causes of death were less often cardiovascular. This suggests that STE-ACS patients without obstructive CAD warrant medical attention and close follow-up.


Assuntos
Síndrome Coronariana Aguda/mortalidade , Doença da Artéria Coronariana/mortalidade , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Sobreviventes , Síndrome Coronariana Aguda/diagnóstico , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico , Dinamarca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Fatores Sexuais , Troponina T/sangue
20.
Am Heart J ; 204: 128-138, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30103092

RESUMO

BACKGROUND: The objective was to compare patients with ischemic heart disease (IHD) undergoing percutaneous coronary intervention (PCI) who were included in randomized controlled trials (RCTs) (trial participants) with patients who were not included (nonparticipants) on a trial-by-trial basis and according to indication for PCI. METHODS: In this cohort study, we compared patients with IHD who were randomized in RCTs in relation to undergoing PCI in Denmark between 2011 and 2015 were considered as RCT-participants in this study. The RCT-participants were compared with contemporary nonparticipants with IHD undergoing PCI in the same period, and they were identified using unselected national registry data. The primary end point was all-cause mortality. RESULTS: A total of 10,317 (30%) patients were included in 10 relevant RCTs (trial participants), and a total of 23,644 (70%) contemporary patients did not participate (nonparticipants). In all the included RCTs, nonparticipants had higher hazard ratios for mortality compared to trial participants (P < .001). Among all patients treated with PCI, the pooled estimates showed a significantly higher mortality rate for nonparticipants compared to trial participants (hazard ratio: 2.03, 95% CI: 1.88-2.19) (P < .001). When patients were stratified according to indication for PCI, the pooled estimates showed a significantly lower mortality rate for trial participants compared to nonparticipants in all strata (P for all < .001). CONCLUSIONS: Trial participants in recently performed RCTs including patients undergoing PCI were not representative of the general population of patients with IHD treated with PCI according to clinical characteristics and mortality. The difference in mortality was found irrespective of the indication for PCI. Thus, results from RCTs including patients undergoing PCI should be extrapolated with caution to the general patient population.


Assuntos
Isquemia Miocárdica/cirurgia , Seleção de Pacientes , Intervenção Coronária Percutânea , Ensaios Clínicos Controlados Aleatórios como Assunto , Idoso , Angina Estável/cirurgia , Angina Instável/cirurgia , Causas de Morte , Dinamarca , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/cirurgia , Isquemia Miocárdica/mortalidade , Readmissão do Paciente , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia
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