328 research outputs found
The role of Slc7a11 in controlling extracellular and intracellular redox environments of lung fibroblasts - potential targets for intervention in aging and idiopathic pulmonary fibrosis.
Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease characterized by extracellular matrix deposition by fibroblasts. Aging and oxidative stress increase the susceptibility to IPF. Redox couples, cysteine/cystine (Cys/CySS) and glutathione/glutathione disulfide (GSH/GSSG), and their redox potentials (Eh) quantify oxidative stress. Fibroblasts from old mice maintain more oxidized extracellular Eh(Cys/CySS) than young mice. Microarray shows down-regulation of Slc7a11 potentially mediates this age-related oxidation. Slc7a11 is the key component of system Xc-, an antiporter that imports CySS and exports glutamate. The first aim of this dissertation is to investigate the mechanistic link between Slc7a11 expression and extracellular Eh(Cys/CySS). The second aim is to evaluate the effects of aging on the redox states of intracellular proteins and whether Slc7a11 contributes to the age-dependent effects. The last aim is to compare SLC7A11 expression, extracellular Eh(Cys/CySS) and intracellular Eh(GSH/GSSG) between human lung fibroblasts from IPF and non-IPF donors and to explore their association with pro-fibrotic gene expression. Slc7a11 expression was manipulated by pharmacological and genetic methods. Reduced and oxidized forms of Cys residues were labelled by Iodoacetyl Tandem Mass Tags. The ratio of oxidized/reduced forms (i.e., redox state) of a Cys residue was determined by multiplexed tandem mass spectrometry. Eh(Cys/CySS) and Eh(GSH/GSSG) were more oxidized in conditioned media of old fibroblasts. Up-regulation of Slc7a11 reduced extracellular Eh(Cys/CySS) for old fibroblasts. Inhibition of GSH synthesis had no effect on the ability of cells to restore their extracellular Eh(Cys/CySS). Redox states of 151 proteins changed with aging. Slc7a11 over-expression restored redox states of 104 proteins. Ingenuity Pathway Analysis showed these 104 proteins were involved in pathways of protein translation initiation, ubiquitin-proteasome-mediated degradation and integrin-cytoskeleton-associated signaling. Slc7a11 expression was lower in IPF fibroblasts. Extracellular Eh(Cys/CySS) was more oxidized and expression of pro-fibrotic genes was higher in IPF fibroblasts. In conclusion, Slc7a11 is the key regulator of extracellular Eh(Cys/CySS). Its effects are independent of GSH synthesis. Aging results in changes of redox states of proteins involved in protein turnover and cytoskeleton dynamics. Up-regulating Slc7a11 restores changes of protein redox states due to aging. Decreased SLC7A11 might represent a susceptibility factor for developing tissue disrepair and fibrosis in IPF
DNA editing in DNA/RNA hybrids by adenosine deaminases that act on RNA.
Adenosine deaminases that act on RNA (ADARs) carry out adenosine (A) to inosine (I) editing reactions with a known requirement for duplex RNA. Here, we show that ADARs also react with DNA/RNA hybrid duplexes. Hybrid substrates are deaminated efficiently by ADAR deaminase domains at dA-C mismatches and with E to Q mutations in the base flipping loop of the enzyme. For a long, perfectly matched hybrid, deamination is more efficient with full length ADAR2 than its isolated deaminase domain. Guide RNA strands for directed DNA editing by ADAR were used to target six different 2΄-deoxyadenosines in the M13 bacteriophage ssDNA genome. DNA editing efficiencies varied depending on the sequence context of the editing site consistent with known sequence preferences for ADARs. These observations suggest the reaction within DNA/RNA hybrids may be a natural function of human ADARs. In addition, this work sets the stage for development of a new class of genome editing tools based on directed deamination of 2΄-deoxyadenosines in DNA/RNA hybrids
Cross-Cultural Emotion Recognition of Angry and Happy Face between China and Indonesia samples
Face emotion recognition have an important ability in surviving in social relations and have been a nosology of anxiety disorder The aim of this study is to test the influence of' culture between Indonesia and China sample. Participants of this study are 40 student from both countries. Two experiments have been conducted to measure the latency and the score of correct answer in recognizing of happy, neutral and angry face. This reserach found that China samples are significant more, faster andhigher score in angry face recognition
MoviePuzzle: Visual Narrative Reasoning through Multimodal Order Learning
We introduce MoviePuzzle, a novel challenge that targets visual narrative
reasoning and holistic movie understanding. Despite the notable progress that
has been witnessed in the realm of video understanding, most prior works fail
to present tasks and models to address holistic video understanding and the
innate visual narrative structures existing in long-form videos. To tackle this
quandary, we put forth MoviePuzzle task that amplifies the temporal feature
learning and structure learning of video models by reshuffling the shot, frame,
and clip layers of movie segments in the presence of video-dialogue
information. We start by establishing a carefully refined dataset based on
MovieNet by dissecting movies into hierarchical layers and randomly permuting
the orders. Besides benchmarking the MoviePuzzle with prior arts on movie
understanding, we devise a Hierarchical Contrastive Movie Clustering (HCMC)
model that considers the underlying structure and visual semantic orders for
movie reordering. Specifically, through a pairwise and contrastive learning
approach, we train models to predict the correct order of each layer. This
equips them with the knack for deciphering the visual narrative structure of
movies and handling the disorder lurking in video data. Experiments show that
our approach outperforms existing state-of-the-art methods on the \MoviePuzzle
benchmark, underscoring its efficacy
Tri-Modal Motion Retrieval by Learning a Joint Embedding Space
Information retrieval is an ever-evolving and crucial research domain. The
substantial demand for high-quality human motion data especially in online
acquirement has led to a surge in human motion research works. Prior works have
mainly concentrated on dual-modality learning, such as text and motion tasks,
but three-modality learning has been rarely explored. Intuitively, an extra
introduced modality can enrich a model's application scenario, and more
importantly, an adequate choice of the extra modality can also act as an
intermediary and enhance the alignment between the other two disparate
modalities. In this work, we introduce LAVIMO (LAnguage-VIdeo-MOtion
alignment), a novel framework for three-modality learning integrating
human-centric videos as an additional modality, thereby effectively bridging
the gap between text and motion. Moreover, our approach leverages a specially
designed attention mechanism to foster enhanced alignment and synergistic
effects among text, video, and motion modalities. Empirically, our results on
the HumanML3D and KIT-ML datasets show that LAVIMO achieves state-of-the-art
performance in various motion-related cross-modal retrieval tasks, including
text-to-motion, motion-to-text, video-to-motion and motion-to-video
Shuo Wen Jie Zi: Rethinking Dictionaries and Glyphs for Chinese Language Pre-training
We introduce CDBERT, a new learning paradigm that enhances the semantics
understanding ability of the Chinese PLMs with dictionary knowledge and
structure of Chinese characters. We name the two core modules of CDBERT as
Shuowen and Jiezi, where Shuowen refers to the process of retrieving the most
appropriate meaning from Chinese dictionaries and Jiezi refers to the process
of enhancing characters' glyph representations with structure understanding. To
facilitate dictionary understanding, we propose three pre-training tasks, i.e.,
Masked Entry Modeling, Contrastive Learning for Synonym and Antonym, and
Example Learning. We evaluate our method on both modern Chinese understanding
benchmark CLUE and ancient Chinese benchmark CCLUE. Moreover, we propose a new
polysemy discrimination task PolyMRC based on the collected dictionary of
ancient Chinese. Our paradigm demonstrates consistent improvements on previous
Chinese PLMs across all tasks. Moreover, our approach yields significant
boosting on few-shot setting of ancient Chinese understanding.Comment: To appear at ACL 2023 Finding
Towards the Transferable Audio Adversarial Attack via Ensemble Methods
In recent years, deep learning (DL) models have achieved significant progress
in many domains, such as autonomous driving, facial recognition, and speech
recognition. However, the vulnerability of deep learning models to adversarial
attacks has raised serious concerns in the community because of their
insufficient robustness and generalization. Also, transferable attacks have
become a prominent method for black-box attacks. In this work, we explore the
potential factors that impact adversarial examples (AEs) transferability in
DL-based speech recognition. We also discuss the vulnerability of different DL
systems and the irregular nature of decision boundaries. Our results show a
remarkable difference in the transferability of AEs between speech and images,
with the data relevance being low in images but opposite in speech recognition.
Motivated by dropout-based ensemble approaches, we propose random gradient
ensembles and dynamic gradient-weighted ensembles, and we evaluate the impact
of ensembles on the transferability of AEs. The results show that the AEs
created by both approaches are valid for transfer to the black box API.Comment: Submitted to Cybersecurity journal 202
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