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1.
Biotechnol Bioeng ; 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39279163

RESUMEN

The influence of extracellular matrix (ECM) stiffness on cell behavior is a well-established phenomenon. Tumor development is associated with the stiffening of the ECM. However, the understanding of the role of biomechanical behavior and mechanotransduction pathways in the oncogenesis of tumor cells remains limited. In this study, we constructed in vitro models using Polydimethylsiloxane substrates to create soft and stiff substrates. We then evaluated the migration of lung cancer cells A549 using video-microscopy and transwell assays. The mechanical properties were assessed through the utilization of atomic force microscopy, Optical Magnetic Twisting Cytometry, and traction force analysis. Additionally, the expression of Calponin 3 (CNN3) was evaluated using reverse transcription­quantitative PCR and immunofluorescence techniques. Our observations indicate that the presence of a stiff substrate enhances A549 motility, as evidenced by increased stiffness and traction force in A549 cells on the stiff substrate. Furthermore, we observed a decrease in CNN3 expression in A549 cells on the stiff substrate. Notably, when CNN3 was overexpressed, it effectively inhibited the migration and invasion of A549 cells on the stiff substrate. The results of our study provide novel perspectives on the mechanisms underlying cancer cell migration in response to substrate mechanical properties.

2.
PLoS One ; 19(9): e0307811, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39240833

RESUMEN

The current mainstream image restoration methods have difficulty fully learning the structure and color information of murals in mural image restoration tasks due to the limited size of the available datasets, resulting in problems such as structural loss and texture errors. This study proposes a two-stage mural restoration network based on an edge-constrained attention mechanism. This paper introduces additional sketches as inputs during the coarse restoration phase and incorporates a local edge loss function to enable the network to generate corresponding structural information based on the sketches. In the fine restoration phase, the calculation for the similarity between missing areas and known areas is optimized to enhance the consistency of the restoration results with the texture of the known areas. Furthermore, a structure-guided attention propagation block is introduced after adopting the attention mechanism. This block selectively integrates surrounding contextual information to update the attention score map, thereby enhancing the coherence and plausibility of the generated textures. The experimental results show that the proposed method outperforms the current mainstream restoration methods according to various assessment indices. The proposed method generates high-quality structural information according to user guidance information, and the repaired texture is highly visually consistent with that of the original mural, with few noticeable deviations. This study provides a new approach for mural restoration, which may positively impact cultural heritage protection and artistic restoration applications.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos
3.
JASA Express Lett ; 4(7)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39046893

RESUMEN

Although the telephone band (0.3-3 kHz) provides sufficient information for speech recognition, the contribution of the non-telephone band (<0.3 and >3 kHz) is unclear. To investigate its contribution, speech intelligibility and talker identification were evaluated using consonants, vowels, and sentences. The non-telephone band produced relatively good intelligibility for consonants (76.0%) and sentences (77.4%), but not vowels (11.5%). The non-telephone band supported good talker identification only with sentences (74.5%), but not vowels (45.8%) or consonants (10.8%). Furthermore, the non-telephone band cannot produce satisfactory speech intelligibility in noise at the sentence level, suggesting the importance of full-band access in realistic listening.


Asunto(s)
Inteligibilidad del Habla , Percepción del Habla , Humanos , Percepción del Habla/fisiología , Masculino , Femenino , Teléfono , Adulto , Adulto Joven , Fonética , Ruido
4.
Proc Natl Acad Sci U S A ; 121(30): e2401926121, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39018190

RESUMEN

Sex pheromones play a crucial role in mate location and reproductive success. Insects face challenges in finding mates in low-density environments. The population dynamics of locusts vary greatly, ranging from solitary individuals to high-density swarms, leading to multiple-trait divergence between solitary and gregarious phases. However, differences in sexual communication between solitary and gregarious locusts have not been sufficiently explored. Herein, we found that solitary locusts but not gregarious ones heavily rely on a single compound, dibutyl phthalate (DBP), for sexual communication. DBP is abundantly released by solitary female locusts and elicits strong attraction of male solitary and gregarious locusts. Solitary adult males display much higher electrophysiological responses to DBP than adult females. Additionally, LmigOr13 was identified as the DBP-specific odorant receptor expressed in neurons housed in basiconic sensilla. Male LmigOr13-/- mutants generated by CRISPR/Cas9 have low electrophysiological responses and behavioral attraction to DBP in both laboratory and field cage experiments. Notably, the attractiveness of DBP to male locusts becomes more evident at lower population densities imposed by controlling the cage size. This finding sheds light on the utilization of a sex pheromone to promote reproductive success in extremely low-density conditions and provides important insights into alternative approaches for population monitoring of locusts.


Asunto(s)
Dibutil Ftalato , Conducta Sexual Animal , Animales , Femenino , Masculino , Conducta Sexual Animal/fisiología , Atractivos Sexuales/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Comunicación Animal
5.
IEEE Trans Biomed Eng ; PP2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008389

RESUMEN

OBJECTIVE: Develop a novel and highly efficient framework that decodes Inferior Colliculus (IC) neural activities for phoneme recognition. METHODS: We propose using Hyperdimensional Computing (HDC) to support an efficient phoneme recognition algorithm, in contrast to widely applied Deep Neural Networks (DNN). The high-dimensional representation and operations in HDC are rooted in human brain functionalities and naturally parallelizable, showing the potential for efficient neural activity analysis. Our proposed method includes a spatial and temporal-aware HDC encoder that effectively captures global and local patterns. As part of our framework, we deploy the lightweight HDC-based algorithm on a highly customizable and flexible hardware platform, i.e., Field Programmable Gate Arrays (FPGA), for optimal algorithm speedup. To evaluate our method, we record IC neural activities on gerbils while playing the sound of different phonemes. RESULTS: We compare our proposed method with multiple baseline machine learning algorithms in recognition quality and learning efficiency, across different hardware platforms. The results show that our method generally achieves better classification quality than the best-performing baseline. Compared to the Deep Residual Neural Network (i.e., ResNet), our method shows a speedup up to 74×, 67×, 210× on CPU, GPU, and FPGA respectively. We achieve up to 15% (10%) higher accuracy in consonant (vowel) classification than ResNet. CONCLUSION: By leveraging brain-inspired HDC for IC neural activity encoding and phoneme classification, we achieve orders of magnitude runtime speedup while improving accuracy in various challenging task settings. SIGNIFICANCE: Decoding IC neural activities is an important step to enhance understanding about human auditory system. However, these responses from the central auditory system are noisy and contain high variance, demanding large-scale datasets and iterative model fine-tuning. The proposed HDC-based framework is more scalable and viable for future real-world deployment thanks to its fast training and overall better quality.

6.
Science ; 385(6706): 295-300, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39024431

RESUMEN

The industrial catalysts utilized for propane dehydrogenation (PDH) to propylene, an important alternative to petroleum-based cracking processes, either use expensive metals or metal oxides that are environmentally unbenign. We report that a typically less-active oxide, titanium oxide (TiO2), can be combined with earth-abundant metallic nickel (Ni) to form an unconventional Ni@TiOx catalyst for efficient PDH. The catalyst demonstrates a 94% propylene selectivity at 40% propane conversion and superior stability under industrially relevant conditions. Complete encapsulation of Ni nanoparticles was allowed at elevated temperatures (>550°C). A mechanistic study suggested that the defective TiOx overlayer consisting of tetracoordinated Ti sites with oxygen vacancies is catalytically active. Subsurface metallic Ni acts as an electronic promoter to accelerate carbon-hydrogen bond activation and hydrogen (H2) desorption on the TiOx overlayer.

8.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167211, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38701957

RESUMEN

The interaction between glioma cells and astrocytes promotes the proliferation of gliomas. Micro-RNAs (miRNAs) carried by astrocyte exosomes (exos) may be involved in this process, but the mechanism remains unclear. The oligonucleotide AS1411, which consists of 26 bases and has a G-quadruplex structure, is an aptamer that targets nucleolin. In this study, we demonstrate exosome-miRNA-27a-mediated cross-activation between astrocytes and glioblastoma and show that AS1411 reduces astrocytes' pro-glioma activity. The enhanced affinity of AS1411 toward nucleolin is attributed to its G-quadruplex structure. After binding to nucleolin, AS1411 inhibits the entry of the NF-κB pathway transcription factor P65 into the nucleus, then downregulates the expression of miRNA-27a in astrocytes surrounding gliomas. Then, AS1411 downregulates astrocyte exosome-miRNA-27a and upregulates the expression of INPP4B, the target gene of miRNA-27a in gliomas, thereby inhibiting the PI3K/AKT pathway and inhibiting glioma proliferation. These results were verified in mouse orthotopic glioma xenografts and human glioma samples. In conclusion, the parallel structure of AS1411 allows it to bind to nucleolin and disrupt the exosome-miRNA-27a-mediated reciprocal activation loop between glioma cells and astrocytes. Our results may help in the development of a novel approach to therapeutic modulation of the glioma microenvironment.


Asunto(s)
Aptámeros de Nucleótidos , Astrocitos , Exosomas , Glioma , MicroARNs , Nucleolina , Oligodesoxirribonucleótidos , Fosfoproteínas , Proteínas de Unión al ARN , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Humanos , Astrocitos/metabolismo , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , MicroARNs/genética , MicroARNs/metabolismo , Animales , Glioma/metabolismo , Glioma/patología , Glioma/genética , Ratones , Oligodesoxirribonucleótidos/genética , Oligodesoxirribonucleótidos/metabolismo , Oligodesoxirribonucleótidos/farmacología , Aptámeros de Nucleótidos/metabolismo , Aptámeros de Nucleótidos/genética , Exosomas/metabolismo , Exosomas/genética , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Ratones Desnudos , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Transducción de Señal
9.
Front Neurol ; 15: 1363053, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38651100

RESUMEN

Purpose: To explore the relationship between obstructive sleep apnea (OSA) and hypoperfusion during ultra-early acute cerebral infarction. Patients and methods: Data were retrospectively collected from patients admitted to our hospital with acute cerebral infarction between January 2020 and January 2022, who underwent comprehensive whole-brain computed tomography perfusion imaging and angiography examinations within 6 h of onset. The F-stroke software automatically assessed and obtained relevant data (Tmax). The patients underwent an initial screening for sleep apnea. Based on their Apnea-Hypopnea Index (AHI), patients were categorized into an AHI ≤15 (n = 22) or AHI >15 (n = 25) group. The pairwise difference of the time-to-maximum of the residue function (Tmax) > 6 s volume was compared, and the correlation between AHI, mean pulse oxygen saturation (SpO2), oxygen desaturation index (ODI), percentage of time with oxygen saturation < 90% (T90%), and the Tmax >6 s volume was analyzed. Results: The Tmax >6 s volume in the AHI > 15 group was significantly larger than that in the AHI ≤ 15 group [109 (62-157) vs. 59 (21-106) mL, p = 0.013]. Spearman's correlation analysis revealed Tmax >6 s volume was significantly correlated with AHI, mean SpO2, ODI, and T90% in the AHI > 15 group, however, no significant correlations were observed in the AHI ≤ 15 group. Controlling for the site of occlusion and Multiphase CT angiography (mCTA) score, AHI (ß = 0.919, p < 0.001), mean SpO2 (ß = -0.460, p = 0.031), ODI (ß = 0.467, p = 0.032), and T90% (ß =0.478, p = 0.026) remained associated with early hypoperfusion in the AHI > 15 group. Conclusion: In patients with acute cerebral infarction and AHI > 15, AHI, mean SpO2, ODI and T90% were associated with early hypoperfusion. However, no such relationship exists among patients with AHI ≤ 15.

10.
JASA Express Lett ; 4(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38573045

RESUMEN

The present study examined English vowel recognition in multi-talker babbles (MTBs) in 20 normal-hearing, native-English-speaking adult listeners. Twelve vowels, embedded in the h-V-d structure, were presented in MTBs consisting of 1, 2, 4, 6, 8, 10, and 12 talkers (numbers of talkers [N]) and a speech-shaped noise at signal-to-noise ratios of -12, -6, and 0 dB. Results showed that vowel recognition performance was a non-monotonic function of N when signal-to-noise ratios were less favorable. The masking effects of MTBs on vowel recognition were most similar to consonant recognition but less so to word and sentence recognition reported in previous studies.


Asunto(s)
Lenguaje , Habla , Adulto , Humanos , Reconocimiento en Psicología , Relación Señal-Ruido
11.
Sci Total Environ ; 918: 170503, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38301776

RESUMEN

Reactive oxygen species (ROS) over-production and oxidative stress resulted from climate change and environmental pollution seriously endangered global fish populations and healthy development of marine aquaculture. Peroxiredoxins (Prxs), a highly conserved family of thiol-specific antioxidants, can mitigate ROS and protect cells from oxidative stress. We previously demonstrated that large yellow croaker PrxIV (LcPrxIV) could not only regulate the pro-inflammatory responses, but also scavenge ROS. However, the underlying mechanism how LcPrxIV regulated immune response and redox homeostasis remains unknown. MicroRNAs (miRNAs) are non-coding RNAs that play important roles in the regulation of various biological processes. In this study, mRNA and miRNA expression profiles from LYCK-pcDNA3.1 and LYCK-PrxIV cells, with or without oxidative stress stimulated by H2O2 were evaluated using high-throughput sequencing. A series of differentially expressed miRNAs (DEMs) and differentially expressed genes (DEGs), as well as DEM-DEG pairs were identified from each two-group comparison, respectively. GO and KEGG functional analyses indicated that most significant DEGs were associated with signaling pathways related to oxidative stress and immune response. Subsequent DEM-DEG interaction analysis revealed that miR-731 and miR-1388 may be involved in both redox regulation and immune response via synergistic effect with LcPrxIV. Interestingly, miR-731 could regulate the expression of different down-stream DEGs under different stimulations of LcPrxIV over-expression, H2O2, or both. Moreover, miR-731 could cause the DEG, γ-glutamyl hydrolase (GGH), to be expressed in opposite ways under different stimulations. On the other hand, the expression of miR-1388 could be negatively or positively regulated under the stimulation of LcPrxIV over-expression with or without oxidative stress, thus regulating gene expression of different mRNAs. Based on these results, we speculate that LcPrxIV may participate in immune response or redox regulation by regulating the expression of different down-stream genes through controlling the expression level of a certain miRNA or by regulating the varieties of expressed miRNAs.


Asunto(s)
MicroARNs , Perciformes , Animales , MicroARNs/genética , Especies Reactivas de Oxígeno/metabolismo , ARN Mensajero/metabolismo , Riñón Cefálico/metabolismo , Peróxido de Hidrógeno/metabolismo , Perciformes/metabolismo , Oxidación-Reducción , Perfilación de la Expresión Génica
12.
Insect Sci ; 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38227554

RESUMEN

Fat body metabolism plays crucial roles in each aspect of insect life traits. Although neuropeptides have been documented to be one of the major neuroendocrinal regulators involved in fat body metabolism, the detailed regulatory mechanism is poorly explored. Here, we conducted comparative metabolome and transcriptome analyses of fat body between wide type (WT) and adipokinetic hormone/corazonin-related peptide (ACP) loss of function mutants of the migratory locust, Locusta migratoria. We found that knockout of ACP resulted in significantly reduced fat body triacylglycerol content but enhanced abundance of phospholipids, particularly phosphatidylcholine and phosphatidylethanolamine. Additionally, the expression levels of genes involved in triacylglycerol and phospholipid synthesis and degradation were significantly altered in the fat body of ACP mutants. Moreover, female ACP mutants displayed much higher fecundity compared to WT females. These findings highlight the important role of neuropeptide ACP in fat body lipid metabolism homeostasis in locusts.

13.
Dalton Trans ; 52(41): 14973-14981, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37807879

RESUMEN

To replace the current expensive precious metal catalysts for water electrolysis, it is important to develop inexpensive and powerful bifunctional catalysts for hydrogen production. It is an effective way to improve catalytic performance using excellent templates and elemental doping. Here, a hierarchical structure Fe-Co3S4/MoS2 was synthesized using an Fe-ZIF precursor prepared by ion exchange, followed by hydrothermal sulfuration and annealing. It required overpotentials of only 93 mV and 243 mV to achieve a current density of 10 mA cm-2 in the HER and OER, respectively. It also showed excellent catalytic performance for overall water splitting, requiring only 1.42 and 1.71 V to achieve current densities of 10 and 100 mA cm-2 in 1 M KOH. The catalyst also demonstrated excellent ultra-long-term stability. The superb catalytic performance and stability can be attributed to the Fe doping, exposing more active sites while retaining the highly stable framework of the ZIF. The component modulation of Co3S4 and MoS2 by Fe doping induced high intrinsic activity and excellent transfer coefficients. This work presents a novel approach to prepare noble metal-free catalysts with highly stable rich interfaces and defects for overall water splitting.

14.
Curr Opin Insect Sci ; 60: 101119, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37741615

RESUMEN

Social insects demonstrate remarkable behavioral flexibility in response to complex external and social environments. One of the most striking examples of this adaptability is the context-dependent division of labor among workers of bees and ants. Neuropeptides, the brain's most diverse group of messenger molecules, play an essential role in modulating this phenotypic plasticity related to labor division in social insects. Integrated omics research and mass spectrometry imaging technology have greatly accelerated the identification and spatiotemporal analysis of neuropeptides. Moreover, key roles of several neuropeptides in age- and caste-dependent behavioral plasticity have been uncovered. This review summarizes recent advances in the characterization, expression, distribution, and functions of neuropeptides in controlling behavioral plasticity in social insects, particularly bees and ants. The article concludes with a discussion of future directions and challenges in understanding the regulation of social behavior by neuropeptides.


Asunto(s)
Hormigas , Neuropéptidos , Abejas , Animales , Conducta Social , Hormigas/metabolismo , Neuropéptidos/metabolismo
15.
Curr Opin Insect Sci ; 60: 101115, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37704097

RESUMEN

Bumble bees are eusocial bees in which the division of labor (DoL) in reproduction and in task performance changes during their annual lifecycle. The queen monopolizes reproduction in young colonies, but at later stages, some workers start to challenge the queen and lay their own unfertilized eggs. The division of colony maintenance and growth tasks relates to worker body size. Reproduction and task performance are regulated by multiple social signals of the queen, the workers, and the brood. Here, we review recent studies suggesting that bumble bees use multiple sources of information to establish and maintain DoL in both reproduction and in task performance. Juvenile hormone (JH) is an important neuroendocrine signal involved in the regulation of DoL in reproduction but not in worker task performance. The reliance on multiple signals facilitates flexibility in face of changes in the social and geophysical environment.


Asunto(s)
Reproducción , Conducta Social , Abejas , Animales , Reproducción/fisiología , Hormonas Juveniles/fisiología
16.
Science ; 381(6660): 886-890, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37498988

RESUMEN

Direct propane dehydrogenation (PDH) to propylene is a desirable commercial reaction but is highly endothermic and severely limited by thermodynamic equilibrium. Routes that oxidatively remove hydrogen as water have safety and cost challenges. We coupled chemical looping-selective hydrogen (H2) combustion and PDH with multifunctional ferric vanadate-vanadium oxide (FeVO4-VOx) redox catalysts. Well-dispersed VOx supported on aluminum oxide (Al2O3) provides dehydrogenation sites, and adjacent nanoscale FeVO4 acts as an oxygen carrier for subsequent H2 combustion. We achieved an integral performance of 81.3% propylene selectivity at 42.7% propane conversion at 550°C for 200 chemical looping cycles for the reoxidization of FeVO4. Based on catalytic experiments, spectroscopic characterization, and theory calculations, we propose a hydrogen spillover-mediated coupling mechanism. The hydrogen species generated at the VOx sites migrated to adjacent FeVO4 for combustion, which shifted PDH toward propylene. This mechanism is favored by the proximity between the dehydrogenation and combustion sites.

17.
Front Psychol ; 14: 1129406, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37425151

RESUMEN

Introduction: This pilot research was designed to investigate if prosodic features from running spontaneous speech could differentiate dementia of the Alzheimer's type (DAT), vascular dementia (VaD), mild cognitive impairment (MCI), and healthy cognition. The study included acoustic measurements of prosodic features (Study 1) and listeners' perception of emotional prosody differences (Study 2). Methods: For Study 1, prerecorded speech samples describing the Cookie Theft picture from 10 individuals with DAT, 5 with VaD, 9 with MCI, and 10 neurologically healthy controls (NHC) were obtained from the DementiaBank. The descriptive narratives by each participant were separated into utterances. These utterances were measured on 22 acoustic features via the Praat software and analyzed statistically using the principal component analysis (PCA), regression, and Mahalanobis distance measures. Results: The analyses on acoustic data revealed a set of five factors and four salient features (i.e., pitch, amplitude, rate, and syllable) that discriminate the four groups. For Study 2, a group of 28 listeners served as judges of emotions expressed by the speakers. After a set of training and practice sessions, they were instructed to indicate the emotions they heard. Regression measures were used to analyze the perceptual data. The perceptual data indicated that the factor underlying pitch measures had the greatest strength for the listeners to separate the groups. Discussion: The present pilot work showed that using acoustic measures of prosodic features may be a functional method for differentiating among DAT, VaD, MCI, and NHC. Future studies with data collected under a controlled environment using better stimuli are warranted.

18.
Chem Sci ; 14(23): 6414-6419, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37325145

RESUMEN

The activation of the C-H bond in heterogeneous catalysis plays a privileged role in converting light alkanes into commodity chemicals with a higher value. In contrast to traditional trial-and-error approaches, developing predictive descriptors via theoretical calculations can accelerate the process of catalyst design. Using density functional theory (DFT) calculations, this work describes tracking C-H bond activation of propane over transition metal catalysts, which is highly dependent on the electronic environment of catalytic sites. Furthermore, we reveal that the occupancy of the antibonding state for metal-adsorbate interaction is the key factor in determining the ability to activate the C-H bond. Among 10 frequently used electronic features, the work function (W) exhibits a strong negative correlation with C-H activation energies. We demonstrate that e-W can effectively quantify the ability of C-H bond activation, surpassing the predictive capacity of the d-band center. The C-H activation temperatures of the synthesized catalysts also confirm the effectiveness of this descriptor. Apart from propane, e-W applies to other reactants like methane.

19.
Nat Ecol Evol ; 7(6): 914-926, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37156891

RESUMEN

Ageing plasticity represents the flexibility of the ageing process in response to non-genetic factors, occurring commonly in animals. However, the regulatory mechanisms underlying ageing plasticity are largely unclear. The density-dependent polyphenism of locusts, Locusta migratoria, displays dramatic lifespan divergence between solitary and gregarious phases, providing a useful system for studying ageing plasticity. Here, we found that gregarious locusts displayed faster locomotor deficits and increased muscle degeneration on ageing than solitary locusts. Comparative transcriptome analysis in flight muscles revealed significant differences in transcriptional patterns on ageing between two phases. RNA interference screening showed that the knockdown of the upregulated PLIN2 gene significantly relieved the ageing-related flight impairments in gregarious locusts. Mechanistically, the gradual upregulation of PLIN2 could induce the accumulation of ectopic lipid droplets and triacylglycerols in flight muscles during the ageing process. Further experiments suggested that ectopic lipid accumulation led to an ageing-related ß-oxidation decline through limiting fatty acid transport and content. These findings reveal the key roles of lipid metabolism in the differences of muscle ageing between solitary and gregarious locusts and provide a potential mechanism underlying environment-induced muscle ageing plasticity.


Asunto(s)
Saltamontes , Animales , Saltamontes/genética , Saltamontes/metabolismo , Transcriptoma , Músculos , Envejecimiento , Lípidos
20.
J Speech Lang Hear Res ; 66(6): 2155-2176, 2023 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-37208163

RESUMEN

PURPOSE: This study assessed the intelligibility of obstruent consonants in prelingually deafened Mandarin-speaking children with cochlear implants (CIs). METHOD: Twenty-two Mandarin-speaking children with normal hearing (NH) aged 3.25-10.0 years and 35 Mandarin-speaking children with CIs aged 3.77-15.0 years were recruited to produce a list of Mandarin words composed of 17 word-initial obstruent consonants in different vowel contexts. The children with CIs were assigned to chronological age-matched (CA) and hearing age-matched (HA) subgroups with reference to the NH controls. One hundred naïve NH adult listeners were recruited for a consonant identification task that consisted of a total of 2,663 stimulus tokens through an online research platform. For each child speaker, the consonant productions were judged by seven to 12 different adult listeners. An average percentage of consonants correct was calculated across all listeners for each consonant. RESULTS: The CI children in both the CA and HA subgroups showed lower intelligibility in their consonant productions than the NH controls. Among the 17 obstruents, both CI subgroups showed higher intelligibility for stops, but they demonstrated major problems with the sibilant fricatives and affricates and showed a different confusion pattern from the NH controls on these sibilants. Of the three places (alveolar, alveolopalatal, and retroflex) in Mandarin sibilants, both CI subgroups showed the lowest intelligibility and the greatest difficulties with alveolar sounds. For the NH children, there was a significant positive relationship between overall consonant intelligibility and chronological age. For the children with CIs, the best fit regression model revealed significant effects of chronological age and age at implantation, with their quadratic terms included. CONCLUSIONS: Mandarin-speaking children with CIs experience major challenges in the three-way place contrasts of sibilant sounds in consonant production. Chronological age and the combined effect of CI-related time variables play important roles in the development of obstruent consonants in the CI children.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Sordera , Percepción del Habla , Adulto , Niño , Humanos , Sordera/cirugía , Audición , Sonido
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