RESUMEN
Recent evidence has demonstrated that the transsynaptic nanoscale organization of synaptic proteins plays a crucial role in regulating synaptic strength in excitatory synapses. However, the molecular mechanism underlying this transsynaptic nanostructure in inhibitory synapses still remains unclear and its impact on synapse function in physiological or pathological contexts has not been demonstrated. In this study, we utilized an engineered proteolysis technique to investigate the effects of acute cleavage of neuroligin-2 (NL2) on synaptic transmission. Our results show that the rapid cleavage of NL2 led to impaired synaptic transmission by reducing both neurotransmitter release probability and quantum size. These changes were attributed to the dispersion of RIM1/2 and GABAA receptors and a weakened spatial alignment between them at the subsynaptic scale, as observed through superresolution imaging and model simulations. Importantly, we found that endogenous NL2 undergoes rapid MMP9-dependent cleavage during epileptic activities, which further exacerbates the decrease in inhibitory transmission. Overall, our study demonstrates the significant impact of nanoscale structural reorganization on inhibitory transmission and unveils ongoing modulation of mature GABAergic synapses through active cleavage of NL2 in response to hyperactivity.
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Moléculas de Adhesión Celular Neuronal , Proteínas del Tejido Nervioso , Sinapsis , Transmisión Sináptica , Animales , Ratones , Moléculas de Adhesión Celular Neuronal/metabolismo , Epilepsia/metabolismo , Epilepsia/fisiopatología , Epilepsia/patología , Hipocampo/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Proteolisis , Receptores de GABA-A/metabolismo , Sinapsis/metabolismo , Transmisión Sináptica/fisiologíaRESUMEN
Genetically encoded calcium indicators (GECIs) are indispensable tools for real-time monitoring of intracellular calcium signals and cellular activities in living organisms. Current GECIs face the challenge of suboptimal peak signal-to-baseline ratio (SBR) with limited resolution for reporting subtle calcium transients. We report herein the development of a suite of calcium sensors, designated NEMO, with fast kinetics and wide dynamic ranges (>100-fold). NEMO indicators report Ca2+ transients with peak SBRs around 20-fold larger than the top-of-the-range GCaMP6 series. NEMO sensors further enable the quantification of absolution calcium concentration with ratiometric or photochromic imaging. Compared with GCaMP6s, NEMOs could detect single action potentials in neurons with a peak SBR two times higher and a median peak SBR four times larger in vivo, thereby outperforming most existing state-of-the-art GECIs. Given their high sensitivity and resolution to report intracellular Ca2+ signals, NEMO sensors may find broad applications in monitoring neuronal activities and other Ca2+-modulated physiological processes in both mammals and plants.
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Calcio , Neuronas , Animales , Calcio/metabolismo , Neuronas/fisiología , Señalización del Calcio/fisiología , Indicadores y Reactivos , Mamíferos/metabolismoRESUMEN
Mitochondria are in a constant balance of fusion and fission. Excessive fission or deficient fusion leads to mitochondrial fragmentation, causing mitochondrial dysfunction and physiological disorders. How the cell prevents excessive fission of mitochondria is not well understood. Here, we report that the fission yeast AAA-ATPase Yta4, which is the homolog of budding yeast Msp1 responsible for clearing mistargeted tail-anchored (TA) proteins on mitochondria, plays a critical role in preventing excessive mitochondrial fission. The absence of Yta4 leads to mild mitochondrial fragmentation in a Dnm1-dependent manner but severe mitochondrial fragmentation upon induction of mitochondrial depolarization. Overexpression of Yta4 delocalizes the receptor proteins of Dnm1, i.e., Fis1 (a TA protein) and Mdv1 (the bridging protein between Fis1 and Dnm1), from mitochondria and reduces the localization of Dnm1 to mitochondria. The effect of Yta4 overexpression on Fis1 and Mdv1, but not Dnm1, depends on the ATPase and translocase activities of Yta4. Moreover, Yta4 interacts with Dnm1, Mdv1, and Fis1. In addition, Yta4 competes with Dnm1 for binding Mdv1 and decreases the affinity of Dnm1 for GTP and inhibits Dnm1 assembly in vitro. These findings suggest a model, in which Yta4 inhibits mitochondrial fission by inhibiting the function of the mitochondrial divisome composed of Fis1, Mdv1, and Dnm1. Therefore, the present work reveals an uncharacterized molecular mechanism underlying the inhibition of mitochondrial fission.
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Demencia Frontotemporal , Schizosaccharomyces , Humanos , ATPasas Asociadas con Actividades Celulares Diversas/genética , Dinámicas Mitocondriales , Adenosina Trifosfatasas , Mitocondrias , Schizosaccharomyces/genéticaRESUMEN
Non-invasive neuroimaging has revealed specific network-based resting-state dynamics in the human brain, yet the underlying neurophysiological mechanism remains unclear. We employed intracranial electroencephalography to characterize local field potentials within the default mode network (DMN), frontoparietal network (FPN), and salience network (SN) in 42 participants. We identified stronger within-network phase coherence at low frequencies (θ and α band) within the DMN, and at high frequencies (γ band) within the FPN. Hidden Markov modeling indicated that the DMN exhibited preferential low frequency phase coupling. Phase-amplitude coupling (PAC) analysis revealed that the low-frequency phase in the DMN modulated the high-frequency amplitude envelopes of the FPN, suggesting frequency-dependent characterizations of intrinsic brain networks at rest. These findings provide intracranial electrophysiological evidence in support of the network model for intrinsic organization of human brain and shed light on the way brain networks communicate at rest.
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Encéfalo , Red Nerviosa , Humanos , Masculino , Femenino , Adulto , Red Nerviosa/fisiología , Red Nerviosa/diagnóstico por imagen , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Red en Modo Predeterminado/fisiología , Red en Modo Predeterminado/diagnóstico por imagen , Adulto Joven , Electrocorticografía , Electroencefalografía/métodosRESUMEN
Bioluminescent indicators are power tools for studying dynamic biological processes. In this study, we present the generation of novel bioluminescent indicators by modifying the luciferin molecule with an analyte-binding moiety. Specifically, we have successfully developed the first bioluminescent indicator for potassium ions (K+), which are critical electrolytes in biological systems. Our approach involved the design and synthesis of a K+-binding luciferin named potassiorin. Additionally, we engineered a luciferase enzyme called BRIPO (bioluminescent red indicator for potassium) to work synergistically with potassiorin, resulting in optimized K+-dependent bioluminescence responses. Through extensive validation in cell lines, primary neurons, and live mice, we demonstrated the efficacy of this new tool for detecting K+. Our research demonstrates an innovative concept of incorporating sensory moieties into luciferins to modulate luciferase activity. This approach has great potential for developing a wide range of bioluminescent indicators, advancing bioluminescence imaging (BLI), and enabling the study of various analytes in biological systems.
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Luciferasas , Mediciones Luminiscentes , Potasio , Potasio/metabolismo , Potasio/química , Animales , Mediciones Luminiscentes/métodos , Ratones , Luciferasas/química , Luciferasas/metabolismo , Humanos , Ingeniería de Proteínas , Sustancias Luminiscentes/química , Luciferina de Luciérnaga/química , Luciferina de Luciérnaga/metabolismoRESUMEN
Serotonin (5-HT) is an important signaling monoamine and neurotransmitter. We report structure-guided engineering of a green fluorescent, genetically encoded serotonin sensor (G-GESS) from a 5-HT-binding lipocalin in the soft tick Argas monolakensis. G-GESS shows fast response kinetics and high affinity, specificity, brightness and photostability. We used G-GESS to image 5-HT dynamics in cultured cells, brain slices and behaving mice.
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Técnicas Biosensibles/métodos , Lipocalinas/metabolismo , Imagen Óptica/métodos , Serotonina/análisis , Animales , Argas/metabolismo , Encéfalo/diagnóstico por imagen , Línea Celular , Células HEK293 , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BLRESUMEN
BACKGROUND: The prognostic significance of obstructive sleep apnea (OSA) in patients with unstable angina (UA) based on remnant cholesterol (RC) or triglyceride (TG) levels remains unclear. This study aims to evaluate the effects of the interaction between RC, TG, and OSA on cardiovascular outcomes in UA patients. METHODS: In this prospective cohort study, OSA was diagnosed when apnea-hypopnea index of ≥ 15 events/h. Patients with high RC (HRC, n = 370) or high TG (HTG, n = 362) included RC or TG in the highest tertile, and those in the middle and lowest tertiles were defined as normal RC (NRC, n = 736) or normal TG (NTG, n = 744). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), including cardiovascular death, myocardial infarction, ischemia stroke, ischemia-driven revascularization, or hospitalization for UA. RESULTS: A total of 1,106 eligible UA patients were enrolled, among which 560 (50.6%) had OSA. RC and TG levels were increased in OSA patients, but there was no difference in the prevalence of OSA between the NRC and HRC or NTG and HTG groups. During a median follow-up of 1.9 (1.1, 3.0) years, OSA was associated with an increased risk of MACCE occurrence compared to non-OSA in UA patients with HRC (adjusted HR 2.06; 95% CI 1.20-3.51, P = 0.008), but not in those with NRC (adjusted HR 1.21; 95% CI 0.84-1.75, P = 0.297). The incremental risk in HRC was attributable to higher rates of hospitalization for UA and ischemia-driven revascularization. Results for HTG and NTG were similar. CONCLUSION: OSA was associated with a worse prognosis in UA patients with HRC or HTG, emphasizing the necessity of identifying OSA presence in this population. TRIAL REGISTRATION: Clinicaltrials.gov; No: NCT03362385.
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Angina Inestable , Biomarcadores , Colesterol , Apnea Obstructiva del Sueño , Triglicéridos , Humanos , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/sangre , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/mortalidad , Apnea Obstructiva del Sueño/complicaciones , Femenino , Angina Inestable/sangre , Angina Inestable/mortalidad , Angina Inestable/diagnóstico , Angina Inestable/epidemiología , Masculino , Estudios Prospectivos , Persona de Mediana Edad , Anciano , Triglicéridos/sangre , Colesterol/sangre , Pronóstico , Biomarcadores/sangre , Factores de Riesgo , Medición de Riesgo , Factores de Tiempo , PrevalenciaRESUMEN
BACKGROUND: The impact of sex on the association of obstructive sleep apnoea (OSA) with recurrent cardiovascular events following acute coronary syndrome (ACS) remains uncertain. This study sought to examine the association between OSA and long-term cardiovascular outcomes in women and men with ACS. METHODS: In this prospective cohort study, we recruited 2160 ACS patients undergoing portable sleep monitoring between June 2015 and January 2020. The primary end-point was major adverse cardiovascular and cerebrovascular event (MACCE), including cardiovascular death, myocardial infarction, stroke, ischaemia-driven revascularisation or hospitalisation for unstable angina or heart failure. RESULTS: After exclusion of patients with failed sleep studies, central sleep apnoea, regular continuous positive airway pressure therapy and loss of follow-up, 1927 patients were enrolled. Among them, 298 (15.5%) were women and 1014 (52.6%) had OSA (apnoea-hypopnoea index ≥15 events·h-1). The prevalence of OSA was 43.0% and 54.4% in women and men, respectively. In 4339â person-years (median 2.9â years, interquartile range 1.5-3.6â years), the cumulative incidence of MACCE was significantly higher in OSA versus non-OSA groups in the overall population (22.4% versus 17.7%; adjusted hazard ratio (HR) 1.29, 95% CI 1.04-1.59; p=0.018). OSA was associated with greater risk of MACCE in women (28.1% versus 18.8%; adjusted HR 1.68, 95% CI 1.02-2.78; p=0.042), but not in men (21.6% versus 17.5%; adjusted HR 1.22, 95% CI 0.96-1.54; p=0.10). No significant interaction was noted between sex and OSA for MACCE (interaction p=0.32). The incremental risk in women was attributable to higher rates of hospitalisation for unstable angina and ischaemia-driven revascularisation. CONCLUSIONS: In hospitalised ACS patients, OSA was associated with increased risk of subsequent events, particularly among women. Female patients with ACS should not be neglected for OSA screening and dedicated intervention studies focusing on women with ACS and comorbid OSA should be prioritised.
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Síndrome Coronario Agudo , Apnea Obstructiva del Sueño , Masculino , Humanos , Femenino , Síndrome Coronario Agudo/complicaciones , Estudios Prospectivos , Factores de Riesgo , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/terapia , Apnea Obstructiva del Sueño/diagnóstico , Angina Inestable/complicaciones , Angina Inestable/epidemiologíaRESUMEN
BACKGROUND: The mortality following ST-segment elevation myocardial infarction (STEMI) remains substantial in the reperfusion era. Shenfu injection, as a traditional Chinese herbal formula, can alleviate ischemia-reperfusion injury through multiple pharmacologic effects. However, no robust data are available regarding the role of Shenfu injection in reducing infarct size for patients with STEMI undergoing primary percutaneous coronary intervention (PPCI). METHODS/DESIGN: This RESTORE trial is a multicenter, randomized, double-blind, parallel-group, placebo-controlled trial (NCT04493840). A total of 326 eligible patients with first-time anterior STEMI undergoing PPCI within 12 h of symptom onset will be enrolled from 10 centers in mainland China. Patients are randomized in a 1:1 fashion to receive either intravenous Shenfu injection (80mL Shenfu injection + 70mL 5% glucose injection) or placebo group (150mL 5% glucose injection) before reperfusion and followed by once a day until 5 days after PPCI. The primary end point is infarct size assessed by cardiac magnetic resonance (CMR) imaging 5±2 days after PPCI. The major secondary end points include enzymatic infarct size, microvascular obstruction, intramyocardial hemorrhage, left ventricular volume and ejection fraction assessed by CMR, as well as cardiovascular events at 30 days. CONCLUSIONS: The RESTORE trial is sufficiently powered to demonstrate the clinical effects of Shenfu injection on myocardial injury in STEMI patients undergoing PPCI in the contemporary era.
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Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Humanos , Infarto del Miocardio con Elevación del ST/tratamiento farmacológico , Infarto del Miocardio con Elevación del ST/diagnóstico , Intervención Coronaria Percutánea/métodos , Imagen por Resonancia Magnética , Método Doble Ciego , Resultado del TratamientoRESUMEN
In this study, 232 class I Newcastle disease viruses (NDVs) were identified from multiple bird species at nationwide live bird markets (LBMs) from 2017 to 2019 in China. Phylogenetic analysis indicated that all 232 isolates were clustered into genotype 1.1.2 of class I on the basis of the fusion (F) gene sequences, which were distinct from the genotypes identified in other countries. Most of the isolates (212/232) were shown to have the typical F gene molecular characteristics of class I NDVs, while a few (20/232) contained mutations at the site of the conventional start codon of the F gene, which resulted in open reading frames (ORFs) altered in length. The isolates with ACG, CTA, and ATA mutations showed different levels of increased virulence and replication capacity, suggesting that these viruses may be transitional types during the evolution of class I NDVs from avirulent to virulent. Further evaluation of biological characteristics with recombinant viruses obtained by reverse genetics demonstrated that the ATG located at genomic positions 4523 to 4525 was the authentic start codon in the F gene of class I NDV, and the specific ATA mutations which contributed to the expression of F protein on the surface of infected cells were the key determinants of increased replication capacity and virulence. Interestingly, the mutation at the corresponding site of genotype II LaSota of class II had no effects on the virulence and replication capacity in chickens. Our results suggest that the alteration of virulence and replication capacity caused by specific mutations in the F gene could be a specific characteristic of class I NDVs and indicate the possibility of the emergence of virulent NDVs due to the persistent circulation of class I NDVs. IMPORTANCE The available information on the distribution, genetic diversity, evolution, and biological characteristics of class I Newcastle disease viruses (NDVs) in domestic poultry is currently very limited. Here, identification of class I NDVs at nationwide live bird markets (LBMs) in China was performed and representative isolates were characterized. A widespread distribution of genotype 1.1.2 of class I NDVs was found in multiple bird species at LBMs in China. Though most isolates demonstrated typical molecular characteristics of class I NDVs, a few that contained specific mutations at the site of the conventional start codon of the fusion gene with increased virulence and replication capacity were identified for the first time. Our findings indicate that the virulence of class I NDVs could have evolved, and the widespread transmission and circulation of class I NDVs may represent a potential threat for disease outbreaks in poultry.
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Enfermedad de Newcastle , Enfermedades de las Aves de Corral , Animales , Pollos/virología , China/epidemiología , Codón Iniciador , Comercio , Monitoreo Epidemiológico/veterinaria , Genotipo , Enfermedad de Newcastle/epidemiología , Virus de la Enfermedad de Newcastle/genética , Filogenia , Aves de Corral/virología , Enfermedades de las Aves de Corral/epidemiología , Virulencia/genéticaRESUMEN
AIMS: Synaptic strength depends strongly on the subsynaptic organisation of presynaptic transmitter release and postsynaptic receptor densities, and their alterations are expected to underlie pathologies. Although synaptic dysfunctions are common pathogenic traits of Alzheimer's disease (AD), it remains unknown whether synaptic protein nano-organisation is altered in AD. Here, we systematically characterised the alterations in the subsynaptic organisation in cellular and mouse models of AD. METHODS: We used immunostaining and super-resolution stochastic optical reconstruction microscopy imaging to quantitatively examine the synaptic protein nano-organisation in both Aß1-42-treated neuronal cultures and cortical sections from a mouse model of AD, APP23 mice. RESULTS: We found that Aß1-42-treatment of cultured hippocampal neurons decreased the synaptic retention of postsynaptic scaffolds and receptors and disrupted their nanoscale alignment to presynaptic transmitter release sites. In cortical sections, we found that while GluA1 receptors in wild-type mice were organised in subsynaptic nanoclusters with high local densities, receptors in APP23 mice distributed more homogeneously within synapses. This reorganisation, together with the reduced overall receptor density, led to reduced glutamatergic synaptic transmission. Meanwhile, the transsynaptic alignment between presynaptic release-guiding RIM1/2 and postsynaptic scaffolding protein PSD-95 was reduced in APP23 mice. Importantly, these reorganisations were progressive with age and were more pronounced in synapses in close vicinity of Aß plaques with dense cores. CONCLUSIONS: Our study revealed a spatiotemporal-specific reorganisation of synaptic nanostructures in AD and identifies dense-core amyloid plaques as the major local inductor in APP23 mice.
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Enfermedad de Alzheimer , Ratones , Animales , Enfermedad de Alzheimer/patología , Sinapsis/patología , Neuronas/patología , Transmisión Sináptica/fisiología , Péptidos beta-Amiloides/metabolismo , Modelos Animales de Enfermedad , Ratones TransgénicosRESUMEN
BACKGROUND: Sporadic studies have examined the impact of OSA on ACS patients by homocysteine (Hcy) level. This study attempted to comprehensively evaluate the effects of the interaction between Hcy and OSA on long-term cardiovascular outcomes in ACS patients. METHODS: In this prospective, large-scale cohort study, 2160 patients admitted for ACS were recruited to undergo overnight sleep monitoring. OSA was diagnosed when apnea-hypopnea index ≥ 15 events/h. Patients with normohomocysteinemia (NHcy) were defined as having serum Hcy ≤ 15 µmol/L, and the others had hyperhomocysteinemia (HHcy). The primary endpoint was major adverse cerebrocardiovascular event (MACCE), a composite of cardiovascular death, myocardial infarction, stroke, ischemia-driven revascularization and hospitalization for unstable angina and heart failure. RESULTS: A total of 1553 eligible ACS patients (average age: 56.3 ± 10.5 years) were enrolled, among which 819 (52.7%) had OSA, and 988 (63.6%) were with NHcy. OSA did not significantly affect the level of Hcy. During a median follow-up of 2.9 (1.6, 3.5) years, after adjustment for clinical confounders, OSA was associated with increased risk for MACCE occurrence versus non-OSA ones in ACS patients with NHcy (adjusted hazard ratio [HR] = 1.36, 95% confidence interval [CI] 1.02-1.83, P = 0.039), but not in those with HHcy (adjusted HR = 0.92, 95%CI 0.62-1.36, P = 0.668). There was an absence of interaction between homocysteine level and OSA in relation to MACCE (interaction P = 0.106). CONCLUSIONS: OSA was independently associated with worse prognosis in ACS patients with NHcy. Our study emphasized the necessity to identify potential presence of OSA in such a population. TRIAL REGISTRATION: ClinicalTrials.gov; Number: NCT03362385; URL: www. CLINICALTRIALS: gov .
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Síndrome Coronario Agudo , Apnea Obstructiva del Sueño , Humanos , Persona de Mediana Edad , Anciano , Pronóstico , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/epidemiología , Estudios Prospectivos , Estudios de Cohortes , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/complicaciones , Homocisteína , Factores de RiesgoRESUMEN
BACKGROUND: As an integral ingredient of human sociality, prosocial behavior requires learning what acts can benefit or harm others. However, it remains unknown how individuals adjust prosocial learning to avoid punishment or to pursue reward. Given that arginine vasopressin (AVP) is a neuropeptide that has been involved in modulating various social behaviors in mammals, it could be a crucial neurochemical facilitator that supports prosocial learning. METHODS: In 50 placebo controls and 54 participants with AVP administration, we examined the modulation of AVP on the prosocial learning characterized by reward and punishment framework, as well as its underlying neurocomputational mechanisms combining computational modeling, event-related potentials and oscillations. RESULTS: We found a self-bias that individuals learn to avoid punishment asymmetrically more severely than reward-seeking. Importantly, AVP increased behavioral performances and learning rates when making decisions to avoid losses for others and to obtain gains for self. These behavioral effects were underpinned by larger responses of stimulus-preceding negativity (SPN) to anticipation, as well as higher punishment-related feedback-related negativity (FRN) for prosocial learning and reward-related P300 for proself benefits, while FRN and P300 neural processes were integrated into theta (4-7 Hz) oscillation at the outcome evaluation stage. CONCLUSIONS: These results suggest that AVP context-dependently up-regulates altruism for concerning others' losses and reward-seeking for self-oriented benefits. Our findings provide insight into the selectively modulatory roles of AVP in prosocial behaviors depending on learning contexts between proself reward-seeking and prosocial punishment-avoidance.
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Electroencefalografía , Castigo , Humanos , Potenciales Evocados/fisiología , Recompensa , VasopresinasRESUMEN
Microbial oils produced by Yarrowia lipolytica offer an environmentally friendly and sustainable alternative to petroleum as well as traditional lipids from animals and plants. The accurate measurement of fermentation parameters, including the substrate concentration, dry cell weight, and lipid accumulation, is the foundation of process control, which is indispensable for industrial lipid production. However, it remains a great challenge to measure the complex parameters online during the lipid fermentation process, which is nonlinear, multivariate, and characterized by strong coupling. As a type of AI technology, the artificial neural network model is a powerful tool for handling extremely complex problems, and it can be employed to develop a soft sensor to monitor the microbial lipid fermentation process of Y. lipolytica. In this study, we first analyzed and emphasized the volume of sodium hydroxide and dissolved oxygen concentration as central parameters of the fermentation process. Then, a soft sensor based on a four-input artificial neural network model was developed, in which the input variables were fermentation time, dissolved oxygen concentration, initial glucose concentration, and additional volume of sodium hydroxide. This provides the possibility of online monitoring of dry cell weight, glucose concentration, and lipid production with high accuracy, which can be extended to similar fermentation processes characterized by the addition of bases or acids, as well as changes of the dissolved oxygen concentration.
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Yarrowia , Animales , Fermentación , Yarrowia/metabolismo , Hidróxido de Sodio/metabolismo , Aceites/metabolismo , Glucosa/metabolismo , Oxígeno/metabolismoRESUMEN
Heterologous expression systems have been used as a powerful experimental strategy to study the function of many proteins, particularly ion transporters. For this experiment, it is fundamental to prepare an expression vector encoding a protein of interest. However, we encountered problems in vector preparation of the voltage sensor domain (VSD) of murine sperm-specific Na+/H+ exchanger (sNHE) due to its severe toxicity to bacteria. We overcame the problems by insertion of an amber stop codon or a synthetic intron into the coding sequence of the VSD in the expression vectors. Both methods allowed us to express the protein of interest in HEK293 cells (combined with a stop codon suppression system for amber codon). The VSD of mouse sNHE generates voltage-dependent outward ionic currents, which is a probable cause of toxicity to bacteria. We propose these two strategies as practical solutions to study the function of any protein toxic to bacteria.
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Protones , Semen , Animales , Bacterias/metabolismo , Codón de Terminación/metabolismo , Células HEK293 , Humanos , Masculino , Ratones , Semen/metabolismo , Sodio/metabolismo , Intercambiadores de Sodio-Hidrógeno/genética , Intercambiadores de Sodio-Hidrógeno/metabolismo , Espermatozoides/metabolismoRESUMEN
The Drosophila testis is an excellent system for studying the process from germ stem cells to motile sperm, including the proliferation of male germ cells, meiosis of primary spermatocytes, mitochondrial morphogenesis, and spermatid individualization. We previously demonstrated that ocnus (ocn) plays an essential role in male germ cell development. Among those genes and proteins whose expression levels were changed as a result of ocn knockdown, cytochrome c1-like (cyt-c1L) was downregulated significantly. Here, we show that cyt-c1L is highly expressed in the testis of D. melanogaster. Knockdown or mutation of cyt-c1L in early germ cells of flies resulted in male sterility. Immunofluorescence staining showed that cyt-c1L knockdown testes had no defects in early spermatogenesis; however, in late stages, in contrast to many individualization complexes (ICs) composed of F-actin cones that appeared at different positions in control testes, no actin cones or ICs were observed in cyt-c1L knockdown testes. Furthermore, no mature sperm were found in the seminal vesicle of cyt-c1L knockdown testes whereas the control seminal vesicle was full of mature sperm with needle-like nuclei. cyt-c1L knockdown also caused abnormal mitochondrial morphogenesis during spermatid elongation. Excessive apoptotic signals accumulated in the base of cyt-c1L knockdown fly testes. These results suggest that cyt-c1L may play an important role in spermatogenesis by affecting the mitochondrial morphogenesis and individualization of sperm in D. melanogaster.
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Proteínas de Drosophila , Drosophila melanogaster , Animales , Masculino , Citocromos c1/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Semen , Espermatogénesis/genética , Testículo , Drosophila/metabolismo , MorfogénesisRESUMEN
The clinical outcome of obstructive sleep apnea in patients with acute coronary syndrome in relation to hyperuricemia is still unclear. We aimed to explore the clinical prognosis of obstructive sleep apnea in patients with acute coronary syndrome in relation to hyperuricemia status. This was a prospective cohort study. We included consecutively eligible patients with acute coronary syndrome who underwent cardiorespiratory polygraphy between June 2015 and January 2020. According to apnea-hypopnea index ≥ 15 events per hr and serum uric acid level, the population was divided into four groups: hyperuricemia with obstructive sleep apnea; hyperuricemia with non-obstructive sleep apnea; no hyperuricemia with obstructive sleep apnea; and no hyperuricemia with non-obstructive sleep apnea. The primary endpoint was major adverse cardiovascular and cerebrovascular events, including cardiovascular death, myocardial infarction, stroke, ischaemia-driven revascularization, and readmission for unstable angina or heart failure. Spearman correlation analysis and Cox regression model were mainly used to estimate the data. The median follow-up was 2.9 years. Among 1925 patients with acute coronary syndrome, 29.6% had hyperuricemia and 52.6% had obstructive sleep apnea. Uric acid was negatively correlated with minimum arterial oxygen saturation and mean arterial oxygen saturation, and positively correlated with apnea-hypopnea index, oxygen desaturation index and the duration of time with arterial oxygen saturation < 90% (p < 0.001). During 2.9 (1.5, 3.6) years of follow-up, obstructive sleep apnea was associated with an increased risk of major adverse cardiovascular and cerebrovascular events in patients with hyperuricemia (23.5% versus 13.4%; adjusted hazard ratio: 1.834; 95% confidence interval: 1.192-2.821, p = 0.006), but not in patients without hyperuricemia (21.9% versus 19.2%; adjusted hazard ratio: 1.131; 95% confidence interval: 0.880-1.453, p = 0.336). There was a correlation between uric acid levels and sleep respiratory indicators. Obstructive sleep apnea was associated with increased risk of major adverse cardiovascular and cerebrovascular events in patients with acute coronary syndrome with hyperuricemia, but not in patients without hyperuricemia.
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Síndrome Coronario Agudo , Apnea Obstructiva del Sueño , Humanos , Síndrome Coronario Agudo/complicaciones , Síndrome Coronario Agudo/epidemiología , Ácido Úrico , Estudios Prospectivos , Factores de Riesgo , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/epidemiologíaRESUMEN
ABSTRACT: The role of phosphodiesterase 5 (Pde5) in obstructive sleep apnea (OSA) induced damage remains unclear. Our study aimed to investigate the role of Pde5 in chronic intermittent hypoxia (CIH) model. C57BL/6J wild-type (WT) mice (n=48) and Pde5 knockout (Pde5-/-) mice (n=24) were randomly assigned to CIH group and room air (RA) group. After 6 weeks, some WT mice (n=24) in CIH group were given sildenafil or saline gavage for another 4 weeks. Blood pressure was regularly measured during the experiment. Echocardiography was used to estimate cardiac function. We collected organs from each group of mice and measured their physical indicators. Histochemical staining was used to explore the size of cardiomyocyte and fibrosis area of various organs. Cyclic guanosine monophosphate (cGMP) and Malondialdehyde (MDA) concentrations in serum were measured by ELISA assay. Compared to the RA-treated group, the 6-week CIH resulted in a significant increase in blood pressure, altered heart structure and reduced serum cGMP in WT mice. Pde5-/- mice and sildenafil intragastric administration significantly reduced systolic blood pressure in CIH condition and attenuated the damage of target organs. In CIH model, we found that the cardiomyocyte size and fibrosis area of heart and kidney significantly reduced in Pde5-/- groups. Besides, endogenous and exogenous inhibition of Pde5 reduced MDA level and inflammatory and oxidative stress markers expression in CIH condition. In the present study, we found that Pde5 inhibition could reduce blood pressure and alleviate target organ damage in the CIH model, which may be mediated through the oxidative stress pathway.
RESUMEN
BACKGROUND: The effects of obstructive sleep apnea (OSA) on the prognosis of acute coronary syndrome (ACS) without revascularization remain unclear, so the aim of the present study was to elucidate the association of OSA with subsequent cardiovascular events in ACS patients with and without revascularization.MethodsâandâResults: We prospectively recruited hospitalized ACS patients undergoing sleep monitoring between June 2015 and January 2020. OSA was defined as an apnea-hypopnea index ≥15 events/h. The primary endpoint was a major adverse cardiovascular and cerebrovascular event (MACCE), including cardiovascular death, myocardial infarction, stroke, ischemia-driven revascularization, or hospitalization for unstable angina or heart failure. Among 1,927 patients, 52.6% had OSA and 69.4% underwent revascularization. During a 2.9-year follow-up (1.5-3.6 years), the risk of MACCE was similar in patients with or without revascularization. OSA was an independent predictor of MACCE in the non-revascularization group (22.6% vs. 14.6%; hazard ratio (HR) 1.861; 95% confidence interval (CI) 1.239-2.796; P=0.003) but not in revascularization group (22.3% vs. 19.3%; HR 1.135; 95% CI 0.882-1.460; P=0.324). The incremental risk in the non-revascularization group was attributable to more hospitalizations for unstable angina (14.2% vs. 8.6%; HR 1.896; 95% CI 1.124-3.199; P=0.016). CONCLUSIONS: For patients with ACS, OSA was independently associated with higher risk of recurrent cardiovascular events among patients without revascularization but not among patients undergoing revascularization. The benefits of suitable OSA treatment for patients without revascularization need further investigation.
Asunto(s)
Síndrome Coronario Agudo , Apnea Obstructiva del Sueño , Humanos , Síndrome Coronario Agudo/complicaciones , Síndrome Coronario Agudo/cirugía , Estudios Prospectivos , Sueño , Angina Inestable/epidemiología , Factores de RiesgoRESUMEN
Trematodes of the genus Ogmocotyle are intestinal flukes that can infect a variety of definitive hosts, resulting in significant economic losses worldwide. However, there are few studies on molecular data of these trematodes. In this study, the mitochondrial (mt) genome of Ogmocotyle ailuri isolated from red panda (Ailurus fulgens) was determined and compared with those from Pronocephalata to investigate the mt genome content, genetic distance, gene rearrangements and phylogeny. The complete mt genome of O. ailuri is a typical closed circular molecule of 14 642 base pairs, comprising 12 protein-coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes and 2 non-coding regions. All genes are transcribed in the same direction. In addition, 23 intergenic spacers and 2 locations with gene overlaps were determined. Sequence identities and sliding window analysis indicated that cox1 is the most conserved gene among 12 PCGs in O. ailuri mt genome. The sequenced mt genomes of the 48 Plagiorchiida trematodes showed 5 types of gene arrangement based on all mt genome genes, with the gene arrangement of O. ailuri being type I. Phylogenetic analysis using concatenated amino acid sequences of 12 PCGs revealed that O. ailuri was closer to Ogmocotyle sikae than to Notocotylus intestinalis. These data enhance the Ogmocotyle mt genome database and provide molecular resources for further studies of Pronocephalata taxonomy, population genetics and systematics.