128 research outputs found
Technical Variables in High-Throughput miRNA Expression Profiling: Much Work Remains to Be Done
MicroRNA (miRNA) gene expression profiling has provided important insights into plant and animal biology. However, there has not been ample published work about pitfalls associated with technical parameters in miRNA gene expression profiling. One source of pertinent information about technical variables in gene expression profiling is the separate and more well-established literature regarding mRNA expression profiling. However, many aspects of miRNA biochemistry are unique. For example, the cellular processing and compartmentation of miRNAs, the differential stability of specific miRNAs, and aspects of global miRNA expression regulation require specific consideration. Additional possible sources of systematic bias in miRNA expression studies include the differential impact of pre-analytical variables, substrate specificity of nucleic acid processing enzymes used in labeling and amplification, and issues regarding new miRNA discovery and annotation. We conclude that greater focus on technical parameters is required to bolster the validity, reliability, and cultural credibility of miRNA gene expression profiling studies
Investigation of temperature stress tolerance in Arabidopsis STTM165/166 using electrophysiology and RNA-Seq
Plant electrical signals have been shown to be generated in response to
various environmental stresses, but the relationship between these signals and
stress tolerance is not well understood. In this study, we used the Arabidopsis
STTM165/166 mutant, which exhibits enhanced temperature tolerance, to examine
this relationship. Surface recording techniques were utilized to compare the
generation ratio and duration characteristics of electrical signals in the
STTM165/166 mutant and wild type (WT). Patch-clamp recording was employed to
assess ion channel currents, specifically those of calcium ions. The current
intensity of the mutant was found to be lower than that of the WT. As calcium
ions are involved in the generation of plant electrical signals, we
hypothesized that the reduced calcium channel activity in the mutant increased
its electrical signal threshold. RNA-Seq analysis revealed differential
expression of AHA genes in the STTM165/166 mutant, which may contribute to the
prolonged depolarization phenotype. Gene Ontology enrichment of differentially
expressed genes (DEGs) identified associations between these DEGs and various
stresses, including temperature, salt, and those related to the jasmonic acid
and abscisic acid pathways. These findings provide experimental evidence for
the use of plant electrical signals in characterizing stress tolerance and
explore potential ion mechanisms through patch-clamp recording and DEG Gene
Ontology analysis. They also emphasize the need for further research on the
relationship between plant electrical signals and stress tolerance.Comment: 20 pages, 5 figure
Study on Growth and Change of Solid Particles with Water Flow in Oilfield Water-Injection Pipeline
The solid particles in oilfield water-injection pipelines with water flow will continuously grow and change, and the oversized solid particles may block the pores of the formation and reduce the oilfield recovery efficiency. Therefore, the study on the growth and change to solid particles during transportation has become a question of interest in oilfields. However, there is little research on this question currently. Therefore, on the basis of the liquid-solid two-phase flow model and the particle population balance model, a growth and change model of solid particles in long-distance water-injection pipelines flowing along water was established in this paper in consideration of the injected water temperature drop along the path, as well as the growth, coalescence, breakage and deposition of particles. Comparison of the field test results indicated that the average error of the particle size distribution fitting degree calculated by the model is 6.9%, and the average error of median diameter is 4.1%. This model was used for analyzing the impact of the flow rate, temperature and median diameter of the united station outlet in a block oilfield of Shengli Oilfield on the solid particle size of the wellheads, and the critical flow rate, temperature and median diameter of the united station outlet were predicted when the median diameter at the wellheads meets the injection requirement (< 2 ÎĽm). The establishment of this model cannot only be used for the study on the growth and change to solid particles in water-injection pipelines flowing along water, but also provides a technical reference for the study on the growth and change to low-concentration solid particles accompanying flow in long-distance liquid/gas phase pipelines
Whole blueberry protects pancreatic beta-cells in diet-induced obese mouse
Background Blueberry is rich in bioactive substances and possesses powerful antioxidant potential, which can protect against oxidant-induced and inflammatory cell damage and cytotoxicity. The aim of this study was to determine how blueberry affects glucose metabolism and pancreatic β-cell proliferation in high fat diet (HFD)-induced obese mice. Methods Wild type male mice at age of 4 weeks received two different kinds of diets: high-fat diet (HFD) containing 60% fat or modified HFD supplemented with 4% (wt:wt) freeze-dried whole blueberry powder (HFD + B) for 14 weeks. A separate experiment was performed in mice fed with low-fat diet (LFD) containing 10% fat or modified LFD + B supplemented with 4% (wt:wt) freeze-dried whole blueberry powder. The metabolic parameters including blood glucose and insulin levels, glucose and insulin tolerances were measured. Results Blueberry-supplemented diet significantly increased insulin sensitivity and glucose tolerance in HFD + B mice compared to HFD mice. However, no difference was observed in blood glucose and insulin sensitivity between LFD + B and LFD mice. In addition, blueberry increased β-cell survival and prevented HFD-induced β-cell expansion. The most important finding was the observation of presence of small scattered islets in blueberry treated obese mice, which may reflect a potential role of blueberry in regenerating pancreatic β-cells. Conclusions Blueberry-supplemented diet can prevent obesity-induced insulin resistance by improving insulin sensitivity and protecting pancreatic β-cells. Blueberry supplementation has the potential to protect and improve health conditions for both type 1 and type 2 diabetes patients
Unimodal Training-Multimodal Prediction: Cross-modal Federated Learning with Hierarchical Aggregation
Multimodal learning has seen great success mining data features from multiple
modalities with remarkable model performance improvement. Meanwhile, federated
learning (FL) addresses the data sharing problem, enabling privacy-preserved
collaborative training to provide sufficient precious data. Great potential,
therefore, arises with the confluence of them, known as multimodal federated
learning. However, limitation lies in the predominant approaches as they often
assume that each local dataset records samples from all modalities. In this
paper, we aim to bridge this gap by proposing an Unimodal Training - Multimodal
Prediction (UTMP) framework under the context of multimodal federated learning.
We design HA-Fedformer, a novel transformer-based model that empowers unimodal
training with only a unimodal dataset at the client and multimodal testing by
aggregating multiple clients' knowledge for better accuracy. The key advantages
are twofold. Firstly, to alleviate the impact of data non-IID, we develop an
uncertainty-aware aggregation method for the local encoders with layer-wise
Markov Chain Monte Carlo sampling. Secondly, to overcome the challenge of
unaligned language sequence, we implement a cross-modal decoder aggregation to
capture the hidden signal correlation between decoders trained by data from
different modalities. Our experiments on popular sentiment analysis benchmarks,
CMU-MOSI and CMU-MOSEI, demonstrate that HA-Fedformer significantly outperforms
state-of-the-art multimodal models under the UTMP federated learning
frameworks, with 15%-20% improvement on most attributes.Comment: 10 pages,5 figure
Screening miRNAs for early diagnosis of colorectal cancer by small RNA deep sequencing and evaluation in a Chinese patient population
Purpose: This study aims to screen microRNAs (miRNAs), for an early diagnosis of colorectal cancer, by deep sequencing and evaluation of total miRNAs using clinical samples from a Chinese patient population.
Methods: Total small RNAs from normal colonic mucosa, colonic adenomas, and colorectal cancer tissues were prepared for miRNA analysis by deep sequencing. The sequencing data were then analyzed by bioinformatics for candidate diagnostic miRNAs, which were further validated for their up- or downregulation status.
Results: Comparison of cancer tissues with normal mucosa identified 99 upregulated and 90 downregulated miRNAs. Comparison of adenomas and normal mucosa found 114 upregulated and 107 downregulated miRNAs. Comparison of cancer and adenoma tissues found 70 upregulated and 27 downregulated miRNAs. Selected up- and downregulated miRNAs were validated for their expressions in 12 cases of patients with cancer and polyps. Specifically, for the upregulated miRNAs, miR-18a-5p and miR-21-3p were significantly upregulated in adenomas and cancer tissues, compared with the normal mucosa; miR-135b-5p, miR-17-5p, miR-182-5p, miR-200a-5p, and miR-200c-3p were significantly upregulated in cancer tissues compared to the normal mucosa, but their differential expression was not significant in adenoma tissues when compared with the normal mucosa. miR-183-5p and miR-96-5p were significantly upregulated in adenoma tissues when compared with normal mucosa, but these differences were not significant in cancer tissues when compared to normal mucosa. For the downregulated miRNAs, miR-133a-3p was significantly downregulated in both adenoma and cancer tissues when compared to normal mucosa; miR-204-5p, miR-125b-5p, miR-139-5p, miR-100-5p, and miR-30a-5p were significantly downregulated in cancer tissues compared to the normal mucosa, but their differential expression was not significant in adenoma tissue compared to normal mucosa.
Conclusion: The findings of this study show that a number of miRNAs might be important in the diagnosis and prognosis of colorectal cancer in Chinese patients using the method of small RNA deep sequencing. Upregulation of miR-18a-5p and miR-21-3p or downregulation of miR-133a-3p in adenoma and cancer tissues may serve as an index for early screening of colorectal cancer. Other miRNAs, such as miR-135b-5p, miR-17-5p, miR-182-5p, miR-200a-5p, miR-200c-3p, miR-183-5p, and miR-96-5p, which were either up- or downregulated, in cancer tissues, but not in adenoma tissues, have limited significance in early diagnosis. Further study is needed to determine a screening index with diagnostic value
The Making of Leaves: How Small RNA Networks Modulate Leaf Development
Leaf development is a sequential process that involves initiation, determination, transition, expansion and maturation. Many coding genes and a few non-coding small RNAs (sRNAs) have been identified as being involved in leaf development. sRNAs and their interactions not only determine gene expression and regulation, but also play critical roles in leaf development through their coordination with other genetic networks and physiological pathways. In this review, we first introduce the biogenesis pathways of sRNAs, mainly microRNAs (miRNAs) and trans-acting small interfering RNAs (ta-siRNAs), and then describe the function of miRNA-transcription factors in leaf development, focusing on guidance by interactive sRNA regulatory networks
The Expression of MicroRNA miR-107 Decreases Early in Alzheimer\u27s Disease and May Accelerate Disease Progression through Regulation of β-Site Amyloid Precursor Protein-Cleaving Enzyme 1
MicroRNAs (miRNAs) are small regulatory RNAs that participate in posttranscriptional gene regulation in a sequence-specific manner. However, little is understood about the role(s) of miRNAs in Alzheimer\u27s disease (AD). We used miRNA expression microarrays on RNA extracted from human brain tissue from the University of Kentucky Alzheimer\u27s Disease Center Brain Bank with near-optimal clinicopathological correlation. Cases were separated into four groups: elderly nondemented with negligible AD-type pathology, nondemented with incipient AD pathology, mild cognitive impairment (MCI) with moderate AD pathology, and AD. Among the AD-related miRNA expression changes, miR-107 was exceptional because miR-107 levels decreased significantly even in patients with the earliest stages of pathology. In situ hybridization with cross-comparison to neuropathology demonstrated that particular cerebral cortical laminas involved by AD pathology exhibit diminished neuronal miR-107 expression. Computational analysis predicted that the 3′-untranslated region (UTR) of β-site amyloid precursor protein-cleaving enzyme 1 (BACE1) mRNA is targeted multiply by miR-107. From the same RNA material analyzed on miRNA microarrays, mRNA expression profiling was performed using Affymetrix Exon Array microarrays on nondemented, MCI, and AD patients. BACE1 mRNA levels tended to increase as miR-107 levels decreased in the progression of AD. Cell culture reporter assays performed with a subset of the predicted miR-107 binding sites indicate the presence of at least one physiological miR-107 miRNA recognition sequence in the 3′-UTR of BACE1 mRNA. Together, the coordinated application of miRNA profiling, Affymetrix microarrays, new bioinformatics predictions, in situ hybridization, and biochemical validation indicate that miR-107 may be involved in accelerated disease progression through regulation of BACE1
The interaction between miR160 and miR165/166 in the control of leaf development and drought tolerance in Arabidopsis
MicroRNAs (miRNAs) are a class of non-coding RNAs that play important roles in plant development and abiotic stresses. To date, studies have mainly focused on the roles of individual miRNAs, however, a few have addressed the interactions among multiple miRNAs. In this study, we investigated the interplay and regulatory circuit between miR160 and miR165/166 and its effect on leaf development and drought tolerance in Arabidopsis using Short Tandem Target Mimic (STTM). By crossing STTM160 Arabidopsis with STTM165/166, we successfully generated a double mutant of miR160 and miR165/166. The double mutant plants exhibited a series of compromised phenotypes in leaf development and drought tolerance in comparison to phenotypic alterations in the single STTM lines. RNA-seq and qRT-PCR analyses suggested that the expression levels of auxin and ABA signaling genes in the STTM-directed double mutant were compromised compared to the two single mutants. Our results also suggested that miR160-directed regulation of auxin response factors (ARFs) contribute to leaf development via auxin signaling genes, whereas miR165/166- mediated HD-ZIP IIIs regulation confers drought tolerance through ABA signaling. Our studies further indicated that ARFs and HD-ZIP IIIs may play opposite roles in the regulation of leaf development and drought tolerance that can be further applied to other crops for agronomic traits improvement
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