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1.
Photoacoustics ; 38: 100622, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38911132

ABSTRACT

Microwave ablation (MWA) is a potent cancer treatment tool, but its effectiveness can be hindered by the lack of visual feedback. This paper validates the feasibility of using microwave-induced thermoacoustic imaging (TAI) technique to monitor the MWA process. A feasibility analysis was conducted at the principle level and a high-performance real-time TAI system was introduced. To address the interference caused by MWA, a robust principal component analysis (RPCA)-based method for TAI was proposed. This method leverages the correlation between multiple signal frames to eliminate interference. RPCA's effectiveness in TAI was demonstrated through three sets of different experiments. Experiments demonstrated that TAI can effectively monitors the MWA process. This work represents the first application of RPCA-related matrix decomposition methods in TAI, paving the way for the application of TAI in more complex clinical scenarios. By providing rapid and accurate visual feedback, this research advances MWA technology.

2.
EMBO J ; 43(12): 2368-2396, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38750259

ABSTRACT

Phosphoglycerate mutase 1 (PGAM1) is a key node enzyme that diverts the metabolic reactions from glycolysis into its shunts to support macromolecule biosynthesis for rapid and sustainable cell proliferation. It is prevalent that PGAM1 activity is upregulated in various tumors; however, the underlying mechanism remains unclear. Here, we unveil that pyruvate kinase M2 (PKM2) moonlights as a histidine kinase in a phosphoenolpyruvate (PEP)-dependent manner to catalyze PGAM1 H11 phosphorylation, that is essential for PGAM1 activity. Moreover, monomeric and dimeric but not tetrameric PKM2 are efficient to phosphorylate and activate PGAM1. In response to epidermal growth factor signaling, Src-catalyzed PGAM1 Y119 phosphorylation is a prerequisite for PKM2 binding and the subsequent PGAM1 H11 phosphorylation, which constitutes a discrepancy between tumor and normal cells. A PGAM1-derived pY119-containing cell-permeable peptide or Y119 mutation disrupts the interaction of PGAM1 with PKM2 and PGAM1 H11 phosphorylation, dampening the glycolysis shunts and tumor growth. Together, these results identify a function of PKM2 as a histidine kinase, and illustrate the importance of enzyme crosstalk as a regulatory mode during metabolic reprogramming and tumorigenesis.


Subject(s)
Glycolysis , Phosphoglycerate Mutase , Thyroid Hormones , Humans , Phosphoglycerate Mutase/metabolism , Phosphoglycerate Mutase/genetics , Phosphorylation , Animals , Thyroid Hormones/metabolism , Thyroid Hormones/genetics , Mice , Thyroid Hormone-Binding Proteins , Neoplasms/metabolism , Neoplasms/genetics , Neoplasms/pathology , Membrane Proteins/metabolism , Membrane Proteins/genetics , Cell Line, Tumor , Carrier Proteins/metabolism , Carrier Proteins/genetics
3.
J Am Chem Soc ; 145(37): 20412-20421, 2023 09 20.
Article in English | MEDLINE | ID: mdl-37651106

ABSTRACT

Somatic mutations are important signatures in clinical cancer treatment. However, accurate detection of rare somatic mutations with low variant-allele frequencies (VAFs) in clinical samples is challenging because of the interference caused by high concentrations of wild-type (WT) sequences. Here, we report a post amplification SNV-specific DNA assembly (PANDA) technology that eliminates the high concentration pressure caused by WT through a mismatch-guided DNA assembly and enables the ultrasensitive detection of cancer mutations with VAFs as low as 0.1%. Because it generates an assembly product that only exposes a single-stranded domain with the minimal length for signal readout and thus eliminates possible interferences from secondary structures and cross-interactions among sequences, PANDA is highly versatile and expandable for multiplex testing. With ultrahigh sensitivity, PANDA enabled the quantitative analysis of EGFR mutations in cell-free DNA of 68 clinical plasma samples and four pleuroperitoneal fluid samples, with test results highly consistent with NGS deep sequencing. Compared to digital PCR, PANDA returned fewer false negatives and ambiguous cases of clinical tests. Meanwhile, it also offers much lower upfront instrumental and operational costs. The multiplexity was demonstrated by developing a 3-plex PANDA for the simultaneous analysis of three EGFR mutations in 54 pairs of tumor and the adjacent noncancerous tissue samples collected from lung cancer patients. Because of the ultrahigh sensitivity, multiplexity, and simplicity, we anticipate that PANDA will find wide applications for analyzing clinically important rare mutations in diverse devastating diseases.


Subject(s)
Cell-Free Nucleic Acids , Lung Neoplasms , Humans , Alleles , Lung Neoplasms/diagnosis , Lung Neoplasms/genetics , DNA/genetics , ErbB Receptors
4.
Chem Commun (Camb) ; 59(57): 8803-8805, 2023 Jul 13.
Article in English | MEDLINE | ID: mdl-37366312

ABSTRACT

Herein, we describe a novel strategy that enables lateral flow readout for DNA strand displacement via disassembling chemical labels (DCL). Comparing it to a classic fluorogenic assay, we demonstrate that our DCL-based lateral flow assay is highly sensitive and specific, capable of discriminating single nucleotide variants in buccal swab samples.


Subject(s)
Biosensing Techniques , DNA/genetics
5.
Article in English | MEDLINE | ID: mdl-35954542

ABSTRACT

Accurate prediction of forest carbon sequestration potential requires a comprehensive understanding of tree growth relationships. However, the studies for estimating carbon sequestration potential concerning tree growth relationships at fine spatial-scales have been limited. In this paper, we assessed the current carbon stock and predicted sequestration potential of Lushan City, where a region has rich vegetation types in southern China, by introducing parameters of diameter at breast height (DBH) and tree height in the method of coupling biomass expansion factor (BEF) and tree growth equation. The partial least squares regression (PLSR) was used to explore the role of combined condition factors (e.g., site, stand, climate) on carbon sequestration potential. The results showed that (1) in 2019, the total carbon stock of trees in Lushan City was 9.22 × 105 t, and the overall spatial distribution exhibited a decreasing tendency from northwest to south-central, and the carbon density increased with elevation; (2) By 2070, the carbon density of forest in Lushan City will reach a relatively stable state, and the carbon stock will continue to rise to 2.15 × 106 t, which is 2.33 times of the current level, indicating that Lushan forest will continue to serve as a carbon sink for the next fifty years; (3) Excluding the effect of tree growth, regional forest carbon sequestration potential was significantly influenced on site characteristics, which achieved the highest Variable Importance in Projection (VIP) value (2.19) for slope direction. Our study provided a better understanding of the relationships between forest growth and carbon sequestration potential at fine spatial-scales. The results regarding the condition factors and how their combination characteristics affect the potential for carbon sequestration could provide crucial insights for Chinese carbon policy and global carbon neutrality goals.


Subject(s)
Carbon Sequestration , Forests , Biomass , Carbon/analysis , China , Trees
6.
Article in English | MEDLINE | ID: mdl-34770154

ABSTRACT

Understanding and assessing ecological vulnerability for estuarine islands are important for maintaining estuarine island ecosystem services and its sustainable development. However, due to its complex fresh water-sea-land interaction mechanism and multiple stressors from both climate change and anthropogenic influence, a comprehensive evaluation of ecological vulnerability for estuarine islands has been limited. Therefore, taking the typical estuary island of Chongming Island as an example, we developed a comprehensive evaluation system of ecological vulnerability for an estuarine island ecosystem based on the pressure-state-response (PSR) conceptual model, and explored the spatial and temporal distribution of ecological vulnerability in 2005 and 2015. The results indicated that the main pressures of Chongming Island from saltwater intrusion intensity and land use intensity were mainly distributed in northern coastal areas and eastern areas of wetland; the ecological vulnerability index (EV) of Chongming Island showed a slight decrease from 2005 to 2015; and three categories of towns based on ecological vulnerability assessment for an eco-island planning and environmental management were identified. Our study provides an effective evaluation system of ecological vulnerability for estuarine islands, which could be helpful for planners and decision makers in improving eco-island planning and environmental management.


Subject(s)
Ecosystem , Rivers , China , Climate Change , Conservation of Natural Resources , Estuaries , Wetlands
7.
Sci Total Environ ; 798: 149107, 2021 Dec 01.
Article in English | MEDLINE | ID: mdl-34325147

ABSTRACT

Uranium (U) pollution is an environmental hazard caused by the development of the nuclear industry. Microbial reduction of hexavalent uranium (U(VI)) to tetravalent uranium (U(IV)) reduces U solubility and mobility and has been proposed as an effective method to remediate uranium contamination. In this review, U(VI) remediation with respect to U(VI)-reducing bacteria, mechanisms, influencing factors, products, and reoxidation are systematically summarized. Reportedly, some metal- and sulfate-reducing bacteria possess excellent U(VI) reduction capability through mechanisms involving c-type cytochromes, extracellular pili, electron shuttle, or thioredoxin reduction. In situ remediation has been demonstrated as an ideal strategy for large-scale degradation of uranium contaminants than ex situ. However, U(VI) reduction efficiency can be affected by various factors, including pH, temperature, bicarbonate, electron donors, and coexisting metal ions. Furthermore, it is noteworthy that the reduction products could be reoxidized when exposed to oxygen and nitrate, inevitably compromising the remediation effects, especially for non-crystalline U(IV) with weak stability.


Subject(s)
Uranium , Water Pollutants, Radioactive , Bacteria , Biodegradation, Environmental , Nitrates , Oxidation-Reduction , Uranium/analysis
8.
Sci Total Environ ; 727: 138364, 2020 Jul 20.
Article in English | MEDLINE | ID: mdl-32334205

ABSTRACT

Resettlement of local people from protected areas (PAs) has been regarded as a preferred method to alleviate human disturbance and environmental pressure. Lack of knowledge about local communities' perceptions of resettlement, however, can lead to failed relocation projects and negative impacts on environmental sustainability and livelihoods. To better understand local communities' perception of relocation in PAs, we examine factors that affect local communities' willingness to relocate in Dashanbao Protected Area (DPA), an important location for conservation of the rare Black-necked Crane and the subject of a large-scale relocation policy in China. We surveyed 512 households in DPA and used multiple logistic regression to identify which factors predict local communities' willingness to relocate. Then, we examined how local communities' opinions of different payment for environmental services programs (PES) impacted their willingness to relocate. The results indicated that participation in a PES program for wetland conservation significantly decreases willingness, while distance from scenic spots and roads increases willingness. Furthermore, participants in the PES program for wetlands had a greater positive perception of the benefits from the DPA. Concern about a sustainable livelihood and loss of a sense of belonging represent the two main categories or 'clusters' of reasons explaining unwillingness to relocate. Our results suggest that prior experience with PES programs influences attitudes about relocation, and that integrating the perception of local communities into policy is important to the success of conservation programs relying on relocation. Managers and decision-makers could usefully consider the coupled relationships between sustainable livelihood strategies such as PES, attitudes toward relocation, and conservation benefits when working with communities in PAs toward enhanced livelihoods and conservation.


Subject(s)
Conservation of Natural Resources , Wetlands , Attitude , China , Humans , Policy
9.
J Mater Chem B ; 1(28): 3506-3512, 2013 Jul 28.
Article in English | MEDLINE | ID: mdl-32260942

ABSTRACT

Effective bone repair and reconstruction after the implantation of Ti-based materials requires the provision of topological cues on the material's surface to promote specific biological responses from the surrounding environment. This is often realized by surface modification. In this paper, micropatterned TiO2 nanotubes are fabricated on a Ti surface via a combination of photolithography and electrochemical anodization, by which micro- and nano-scale geometry can be controlled. The preparation conditions are optimized and the interaction between the micropatterning (via photolithography) and nanopatterning (via electrochemical anodization) processes is investigated in detail. The resulting materials are then used for protein adsorption and a cell adhesion test. It is found that protein adsorption and cell adhesion can "trace" the topological cues by presenting high selectivity between the micropatterned TiO2 nanotubes and the Ti surface. We hope our study can benefit the research of Ti-based repairing materials, especially for those which need to manipulate protein adsorption and cell adhesion behavior.

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