114 research outputs found
Sphingomyelin synthase overexpression increases cholesterol accumulation and decreases cholesterol secretion in liver cells
<p>Abstract</p> <p>Background</p> <p>Studies have shown that plasma high density lipoprotein cholesterol levels are negatively correlated with the development of atherosclerosis, whereas epidemiological studies have also shown that plasma sphingomyelin level is an independent risk factor for atherosclerosis.</p> <p>Methods</p> <p>To evaluate the relationship between cellular sphingomyelin level and cholesterol metabolism, we created two cell lines that overexpressed sphingomyelin synthase 1 or 2 (SMS1 or SMS2), using the Tet-off expression system.</p> <p>Results</p> <p>We found that SMS1 or SMS2 overexpression in Huh7 cells, a human hepatoma cell line, significantly increased the levels of intracellular sphingomyelin, cholesterol, and apolipoprotein A-I and decreased levels of apolipoprotein A-I and cholesterol in the cell culture medium, implying a defect in both processes.</p> <p>Conclusions</p> <p>Our findings indicate that the manipulation of sphingomyelin synthase activity could influence the metabolism of sphingomyelin, cholesterol and apolipoprotein A-I.</p
Recent controversies in liver transplantation
The chronicle backdrop of liver transplantation (LT) is an intricate story to reveal- it is an adventure of extraordinary achievement and catastrophic disappointments. Historically, controversies and LT seems to be synonymous.
Despite the improvements in results, LT is still facing lots of challenges and controversies, whereby demand is high but the resources, primarily concerned to donor, are very limited.
We have focused our perspective on LT for HCV-related cirrhosis and nutritional support for cachectic patients awaiting LT
Towards Authentic Face Restoration with Iterative Diffusion Models and Beyond
An authentic face restoration system is becoming increasingly demanding in
many computer vision applications, e.g., image enhancement, video
communication, and taking portrait. Most of the advanced face restoration
models can recover high-quality faces from low-quality ones but usually fail to
faithfully generate realistic and high-frequency details that are favored by
users. To achieve authentic restoration, we propose , an
teratively learned face restoration system based on denoising
iffusion odels (DDMs). We define the criterion of an
authentic face restoration system, and argue that denoising diffusion models
are naturally endowed with this property from two aspects: intrinsic iterative
refinement and extrinsic iterative enhancement. Intrinsic learning can preserve
the content well and gradually refine the high-quality details, while extrinsic
enhancement helps clean the data and improve the restoration task one step
further. We demonstrate superior performance on blind face restoration tasks.
Beyond restoration, we find the authentically cleaned data by the proposed
restoration system is also helpful to image generation tasks in terms of
training stabilization and sample quality. Without modifying the models, we
achieve better quality than state-of-the-art on FFHQ and ImageNet generation
using either GANs or diffusion models.Comment: ICCV 202
Variations in protein concentration and nitrogen sources in different positions of grain in wheat
The distribution patterns of total protein and protein components in different layers of wheat grain were investigated using the pearling technique, and the sources of different protein components and pearling fractions were identified using (15)N isotope tracing methods. It was found that N absorbed from jointing to anthesis (JA) and remobilized to the grain after anthesis was the principal source of grain N, especially in the outer layer. For albumin and globulin, the amount of N absorbed during different stages all showed a decreasing trend from the surface layer to the center part. Whereas, for globulin and glutenin, the N absorbed after anthesis accounted for the main part indicating that for storage protein, the utilization of N assimilated after anthesis is greater than that of the stored N assimilated before anthesis. It is concluded that manipulation of the N application rate during different growth stages could be an effective approach to modulate the distribution of protein fractions in pearled grains for specific end-uses
HyperDreamBooth: HyperNetworks for Fast Personalization of Text-to-Image Models
Personalization has emerged as a prominent aspect within the field of
generative AI, enabling the synthesis of individuals in diverse contexts and
styles, while retaining high-fidelity to their identities. However, the process
of personalization presents inherent challenges in terms of time and memory
requirements. Fine-tuning each personalized model needs considerable GPU time
investment, and storing a personalized model per subject can be demanding in
terms of storage capacity. To overcome these challenges, we propose
HyperDreamBooth-a hypernetwork capable of efficiently generating a small set of
personalized weights from a single image of a person. By composing these
weights into the diffusion model, coupled with fast finetuning, HyperDreamBooth
can generate a person's face in various contexts and styles, with high subject
details while also preserving the model's crucial knowledge of diverse styles
and semantic modifications. Our method achieves personalization on faces in
roughly 20 seconds, 25x faster than DreamBooth and 125x faster than Textual
Inversion, using as few as one reference image, with the same quality and style
diversity as DreamBooth. Also our method yields a model that is 10000x smaller
than a normal DreamBooth model. Project page: https://hyperdreambooth.github.ioComment: project page: https://hyperdreambooth.github.i
Mechano-stimulated modifications in the chloroplast antioxidant system and proteome changes are associated with cold response in wheat
BACKGROUND: Mechanical wounding can cause morphological and developmental changes in plants, which may affect the responses to abiotic stresses. However, the mechano-stimulation triggered regulation network remains elusive. Here, the mechano-stimulation was applied at two different times during the growth period of wheat before exposing the plants to cold stress (5.6 °C lower temperature than the ambient temperature, viz., 5.0 °C) at the jointing stage. RESULTS: Results showed that mechano-stimulation at the Zadoks growth stage 26 activated the antioxidant system, and substantially, maintained the homeostasis of reactive oxygen species. In turn, the stimulation improved the electron transport and photosynthetic rate of wheat plants exposed to cold stress at the jointing stage. Proteomic and transcriptional analyses revealed that the oxidative stress defense, ATP synthesis, and photosynthesis-related proteins and genes were similarly modulated by mechano-stimulation and the cold stress. CONCLUSIONS: It was concluded that mechano-stimulated modifications of the chloroplast antioxidant system and proteome changes are related to cold tolerance in wheat. The findings might provide deeper insights into roles of reactive oxygen species in mechano-stimulated cold tolerance of photosynthetic apparatus, and be helpful to explore novel approaches to mitigate the impacts of low temperature occurring at critical developmental stages. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12870-015-0610-6) contains supplementary material, which is available to authorized users
Taming Encoder for Zero Fine-tuning Image Customization with Text-to-Image Diffusion Models
This paper proposes a method for generating images of customized objects
specified by users. The method is based on a general framework that bypasses
the lengthy optimization required by previous approaches, which often employ a
per-object optimization paradigm. Our framework adopts an encoder to capture
high-level identifiable semantics of objects, producing an object-specific
embedding with only a single feed-forward pass. The acquired object embedding
is then passed to a text-to-image synthesis model for subsequent generation. To
effectively blend a object-aware embedding space into a well developed
text-to-image model under the same generation context, we investigate different
network designs and training strategies, and propose a simple yet effective
regularized joint training scheme with an object identity preservation loss.
Additionally, we propose a caption generation scheme that become a critical
piece in fostering object specific embedding faithfully reflected into the
generation process, while keeping control and editing abilities. Once trained,
the network is able to produce diverse content and styles, conditioned on both
texts and objects. We demonstrate through experiments that our proposed method
is able to synthesize images with compelling output quality, appearance
diversity, and object fidelity, without the need of test-time optimization.
Systematic studies are also conducted to analyze our models, providing insights
for future work
QTL Mapping of Fiber-Related Traits Based on a High-Density Genetic Map in Flax (Linum usitatissimum L.)
A genetic map is an important and valuable tool for quantitative trait locus (QTL) mapping, marker-assisted selection (MAS)-based breeding, and reference-assisted chromosome assembly. In this study, 112 F2 plants from a cross between Linum usitatissimum L. “DIANE” and “NY17” and parent plants were subjected to high-throughput sequencing and specific-locus amplified fragment (SLAF) library construction. After preprocessing, 61.64 Gb of raw data containing 253.71 Mb paired-end reads, each 101 bp in length, were obtained. A total of 192,797 SLAFs were identified, of which 23,115 were polymorphic, with a polymorphism rate of 11.99%. Finally, 2,339 SLAFs were organized into a linkage map consisting of 15 linkage groups (LGs). The total length of the genetic map was 1483.25 centimorgans (cM) and the average distance between adjacent markers was 0.63 cM. Combined with flax chromosome-scale pseudomolecules, 12 QTLs associating with 6 flax fiber-related traits were mapped on the chromosomal scaffolds. This high-density genetic map of flax should serve as a foundation for flax fine QTL mapping, draft genome assembly, and MAS-guided breeding. Ultimately, the genomic regions identified in this research could potentially be valuable for improving flax fiber cultivars, as well as for identification of candidate genes involved in flax fiber formation processes.Significance statementA high-density genetic map of flax was constructed, and QTLs were identified on the sequence scaffolds to be interrelated with fiber-related traits. The results of this study will not only provide a platform for gene/QTL fine mapping, map-based gene isolation, and molecular breeding for flax, but also provide a reference to help position sequence scaffolds on the physical map and assist in the process of assembling the flax genome sequence
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