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1.
Immunity ; 48(4): 675-687.e7, 2018 04 17.
Article in English | MEDLINE | ID: mdl-29653696

ABSTRACT

Manganese (Mn) is essential for many physiological processes, but its functions in innate immunity remain undefined. Here, we found that Mn2+ was required for the host defense against DNA viruses by increasing the sensitivity of the DNA sensor cGAS and its downstream adaptor protein STING. Mn2+ was released from membrane-enclosed organelles upon viral infection and accumulated in the cytosol where it bound directly to cGAS. Mn2+ enhanced the sensitivity of cGAS to double-stranded DNA (dsDNA) and its enzymatic activity, enabling cGAS to produce secondary messenger cGAMP in the presence of low concentrations of dsDNA that would otherwise be non-stimulatory. Mn2+ also enhanced STING activity by augmenting cGAMP-STING binding affinity. Mn-deficient mice showed diminished cytokine production and were more vulnerable to DNA viruses, and Mn-deficient STING-deficient mice showed no increased susceptibility. These findings indicate that Mn is critically involved and required for the host defense against DNA viruses.


Subject(s)
DNA Virus Infections/immunology , DNA Viruses/immunology , DNA, Viral/immunology , Manganese/metabolism , Membrane Proteins/metabolism , Nucleotidyltransferases/metabolism , Adult , Animals , Cell Line , Cricetinae , Enzyme Activation/immunology , Female , HEK293 Cells , HeLa Cells , Host-Pathogen Interactions , Humans , Immunity, Innate/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , Young Adult
2.
Nano Lett ; 24(14): 4108-4116, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38536003

ABSTRACT

Symmetry breaking plays a pivotal role in unlocking intriguing properties and functionalities in material systems. For example, the breaking of spatial and temporal symmetries leads to a fascinating phenomenon: the superconducting diode effect. However, generating and precisely controlling the superconducting diode effect pose significant challenges. Here, we take a novel route with the deliberate manipulation of magnetic charge potentials to realize unconventional superconducting flux-quantum diode effects. We achieve this through suitably tailored nanoengineered arrays of nanobar magnets on top of a superconducting thin film. We demonstrate the vital roles of inversion antisymmetry and its breaking in evoking unconventional superconducting effects, namely a magnetically symmetric diode effect and an odd-parity magnetotransport effect. These effects are nonvolatilely controllable through in situ magnetization switching of the nanobar magnets. Our findings promote the use of antisymmetry (breaking) for initiating unconventional superconducting properties, paving the way for exciting prospects and innovative functionalities in superconducting electronics.

3.
Biochem Biophys Res Commun ; 695: 149415, 2024 02 05.
Article in English | MEDLINE | ID: mdl-38159411

ABSTRACT

Macular edema (ME) has emerged as a leading cause of visual impairment, representing a critical clinical manifestation and complication associated with many eye diseases. In the occurrence and development of ME, retinal glial cells like Müller cells and microglial cells play vital roles. Moreover, growth factor and cytokines associated with them, such as vascular endothelial growth factor (VEGF), pigment epithelium-derived factor (PEDF), hypoxia-inducible factor-1α (HIF-1α), angiopoietin-like protein 4 (ANGPTL4), interleukin-6(IL-6), interleukin-8 (IL-8), monocyte chemoattractant protein-1 (MCP-1), prostaglandin, etc., also take part in the pathogenesis of ME. Changes in these cytokines can lead to retinal angiogenesis, increased vascular permeability, blood-retinal barrier (BRB) breakdown, and fluid leakage, further causing ME to occur or deteriorate. Research on the role of retinal glial cells and related cytokines in ME will provide new therapeutic directions and effective remedies. This article is a literature review on the role of Müller cells, microglial cells and related factors in ME pathogenesis.


Subject(s)
Macular Edema , Humans , Vascular Endothelial Growth Factor A/metabolism , Retina/metabolism , Neuroglia/metabolism , Cytokines/metabolism
4.
Cell Commun Signal ; 22(1): 290, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38802833

ABSTRACT

The Crumbs protein (CRB) family plays a crucial role in maintaining the apical-basal polarity and integrity of embryonic epithelia. The family comprises different isoforms in different animals and possesses diverse structural, localization, and functional characteristics. Mutations in the human CRB1 or CRB2 gene may lead to a broad spectrum of retinal dystrophies. Various CRB-associated experimental models have recently provided mechanistic insights into human CRB-associated retinopathies. The knowledge obtained from these models corroborates the importance of CRB in retinal development and maintenance. Therefore, complete elucidation of these models can provide excellent therapeutic prospects for human CRB-associated retinopathies. In this review, we summarize the current animal models and human-derived models of different CRB family members and describe the main characteristics of their retinal phenotypes.


Subject(s)
Membrane Proteins , Retinal Diseases , Humans , Animals , Membrane Proteins/genetics , Membrane Proteins/metabolism , Retinal Diseases/genetics , Retinal Diseases/pathology , Retinal Diseases/metabolism , Retina/metabolism , Retina/pathology , Eye Proteins/genetics , Eye Proteins/metabolism , Disease Models, Animal , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Mutation
5.
Mol Biol Rep ; 51(1): 166, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38252343

ABSTRACT

BACKGROUND: Genomic imprinting refers to expressing parent-specific genes in mammalian diploid cells. The NDN gene is maternally imprinted in humans and mice and correlates with the timing of puberty. This study aimed to investigate its imprinting status and its relationship with the onset of puberty in Dolang sheep. METHODS AND RESULTS: In this study, cloning and sequencing obtained the NDN gene cDNA sequence of 1082 bp of Dolang sheep, coding for 325 amino acids. Similarity analysis and phylogenetic tree showed that the NDN gene conformed to the law of speciation and was highly conserved among mammals. RT-qPCR results showed the highest expression of NDN mRNA was found in the hypothalamus at puberty, and the expression was significantly increased and then significantly decreased from prepuberty to postpuberty in the hypothalamus, pituitary, and ovary and oviduct. Based on expressed single nucleotide polymorphism (SNP), the NDN gene was expressed monoallelically in the tissues of adult and neonatal umbilical cords, and the expressed allele was paternally inherited. The NDN promoter region of 3400 bp was obtained by cloning and identified in monoallelic-expressing tissues (hypothalamus, ovary, spleen) as a differentially methylated region (DMR). CONCLUSION: These findings will enrich the number of imprinted genes in sheep and suggest that the NDN gene could be a candidate gene for studying puberty initiation in Dolang sheep.


Subject(s)
Amino Acids , Genes, cdc , Animals , Female , Alleles , Cloning, Molecular , Phylogeny , Sheep/genetics
6.
Cell ; 139(4): 679-92, 2009 Nov 13.
Article in English | MEDLINE | ID: mdl-19914164

ABSTRACT

Signaling proteins driving the proliferation of stem and progenitor cells are often encoded by proto-oncogenes. EphB receptors represent a rare exception; they promote cell proliferation in the intestinal epithelium and function as tumor suppressors by controlling cell migration and inhibiting invasive growth. We show that cell migration and proliferation are controlled independently by the receptor EphB2. EphB2 regulated cell positioning is kinase-independent and mediated via phosphatidylinositol 3-kinase, whereas EphB2 tyrosine kinase activity regulates cell proliferation through an Abl-cyclin D1 pathway. Cyclin D1 regulation becomes uncoupled from EphB signaling during the progression from adenoma to colon carcinoma in humans, allowing continued proliferation with invasive growth. The dissociation of EphB2 signaling pathways enables the selective inhibition of the mitogenic effect without affecting the tumor suppressor function and identifies a pharmacological strategy to suppress adenoma growth.


Subject(s)
Receptor, EphB2/metabolism , Signal Transduction , Animals , Cell Movement , Cell Proliferation , Cyclin D1/metabolism , Epithelium , Humans , Intestine, Small/cytology , Intestine, Small/metabolism , Male , Mice , Stem Cells/cytology
7.
Appl Opt ; 63(2): 525-534, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38227250

ABSTRACT

Sky-bionic polar co-ordinate navigation is an effective means of providing navigational information in the absence of a priori information. Polar co-ordinate navigation during clear daytime conditions has been studied, but there has been a lack of research of it at night due to problems with noise. Therefore, in this paper, a short-wave infrared polarimetric sensor system is designed, which is capable of acquiring atmospheric polarimetric information in low illumination environments at night, compared with traditional visible band sensors. Additionally, based on the statistics of polarization angle information, an algorithm for removing noise and starlight is proposed to solve the influence of starlight and noise on the polarization information at night. After many outdoor experiments, we found that the method can output the heading angle stably and accurately, and its standard deviation is controlled to be 0.42° in a clear night.

8.
Proc Natl Acad Sci U S A ; 118(42)2021 10 19.
Article in English | MEDLINE | ID: mdl-34625471

ABSTRACT

Cellular ionic concentrations are a central factor orchestrating host innate immunity, but no pathogenic mechanism that perturbs host innate immunity by directly targeting metal ions has yet been described. Here, we report a unique virulence strategy of Yersinia pseudotuberculosis (Yptb) involving modulation of the availability of Mn2+, an immunostimulatory metal ion in host cells. We showed that the Yptb type VI secretion system (T6SS) delivered a micropeptide, TssS, into host cells to enhance its virulence. The mutant strain lacking TssS (ΔtssS) showed substantially reduced virulence but induced a significantly stronger host innate immune response, indicating an antagonistic role of this effector in host antimicrobial immunity. Subsequent studies revealed that TssS is a Mn2+-chelating protein and that its Mn2+-chelating ability is essential for the disruption of host innate immunity. Moreover, we showed that Mn2+ enhances the host innate immune response to Yptb infection by activating the stimulator of interferon genes (STING)-mediated immune response. Furthermore, we demonstrated that TssS counteracted the cytoplasmic Mn2+ increase to inhibit the STING-mediated innate immune response by sequestering Mn2+ Finally, TssS-mediated STING inhibition sabotaged bacterial clearance in vivo. These results reveal a previously unrecognized bacterial immune evasion strategy involving modulation of the bioavailability of intracellular metal ions and provide a perspective on the role of the T6SS in pathogenesis.


Subject(s)
Immunity, Innate , Manganese/metabolism , Membrane Proteins/metabolism , Type VI Secretion Systems , Animals , Mice , Mice, Inbred C57BL , Protein Binding , Protein Transport , Yersinia pseudotuberculosis/metabolism , Yersinia pseudotuberculosis/pathogenicity
9.
Pharm Stat ; 23(2): 204-218, 2024.
Article in English | MEDLINE | ID: mdl-38014753

ABSTRACT

The propensity score-integrated composite likelihood (PSCL) method is one method that can be utilized to design and analyze an application when real-world data (RWD) are leveraged to augment a prospectively designed clinical study. In the PSCL, strata are formed based on propensity scores (PS) such that similar subjects in terms of the baseline covariates from both the current study and RWD sources are placed in the same stratum, and then composite likelihood method is applied to down-weight the information from the RWD. While PSCL was originally proposed for a fixed design, it can be extended to be applied under an adaptive design framework with the purpose to either potentially claim an early success or to re-estimate the sample size. In this paper, a general strategy is proposed due to the feature of PSCL. For the possibility of claiming early success, Fisher's combination test is utilized. When the purpose is to re-estimate the sample size, the proposed procedure is based on the test proposed by Cui, Hung, and Wang. The implementation of these two procedures is demonstrated via an example.


Subject(s)
Research Design , Humans , Propensity Score , Sample Size
10.
Pharm Stat ; 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38442919

ABSTRACT

In a randomized controlled trial with time-to-event endpoint, some commonly used statistical tests to test for various aspects of survival differences, such as survival probability at a fixed time point, survival function up to a specific time point, and restricted mean survival time, may not be directly applicable when external data are leveraged to augment an arm (or both arms) of an RCT. In this paper, we propose a propensity score-integrated approach to extend such tests when external data are leveraged. Simulation studies are conducted to evaluate the operating characteristics of three propensity score-integrated statistical tests, and an illustrative example is given to demonstrate how these proposed procedures can be implemented.

11.
Angew Chem Int Ed Engl ; 63(10): e202318750, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38265178

ABSTRACT

The chemically catalyzed production of fructose syrup from high concentrations of glucose is crucial for the food industry and biorefining. In this work, a single crystal catalyst was synthesized via protective desilication of zeolite while incorporating indium. Glucose was isomerized in methanol at concentrations as high as 33 wt % before being hydrolyzed with water. The final fructose production was 54.9 %, with 89.1 % selectivity and 93.3 % sugar recovery, the highest isomerization rate at the highest concentration ever reported. Indium was present in the single-crystal catalyst as oxide nanoparticles and boundary framework atoms, and it achieved intelligent cooperation in the production of fructose syrup in methanol by catalyzing isomerization and selective glycosidation, minimizing degradation due to fructose accumulation and eliminating side reactions. This study contributed to the advancement of the industrial practice of chemically catalyzed glucose isomerization.

12.
Anal Chem ; 95(30): 11449-11455, 2023 08 01.
Article in English | MEDLINE | ID: mdl-37477343

ABSTRACT

The blood-brain barrier (BBB) is essential for maintaining central nervous system (CNS) stability, and neuroinflammation may cause the dysfunction of the BBB. MicroRNA-146a (miR-146a) is closely associated with neuroinflammation, which showed significant upregulation in response to lipopolysaccharide (LPS) induction. Elucidating the relationship between LPS-induced miR-146a expression and the BBB could decipher the mechanism of many neurological diseases. Here, we constructed an in vitro microfluidic human-BBB (µF-hBBB) chip consisting of human umbilical vein vascular endothelial cells (HUVECs) and human astrocyte (HAs) cells. A tetrahedral DNA framework (TDF-3MB) nanoprobe was used to label miR-146a in HUVECs on µF-hBBB chips before and after LPS induction, and the study revealed a significant increase in miR-146a expression after LPS induction. We believe that such a µF-hBBB chip is a promising in vitro platform for further use in understanding CNS diseases.


Subject(s)
Lipopolysaccharides , MicroRNAs , Humans , Lipopolysaccharides/pharmacology , MicroRNAs/genetics , MicroRNAs/metabolism , Blood-Brain Barrier/metabolism , Neuroinflammatory Diseases , Microfluidics , Inflammation/chemically induced , Inflammation/metabolism , Human Umbilical Vein Endothelial Cells/metabolism , DNA
13.
Opt Express ; 31(21): 33776-33786, 2023 Oct 09.
Article in English | MEDLINE | ID: mdl-37859150

ABSTRACT

A multispectral silicon-based photodetector structure with stacked PN junctions is proposed in this study. The substrate layer of the proposed photodetector consists of four vertically stacked PN junction structures that contain four photodiodes. The designed structure achieves quantum efficiency of up to 70% and a response time of 5.1 × 10-8 s. The proposed photodetector has a simple structure, and the vertically stacked PN junction structure not only reduces the phenomenon of color aliasing, but also achieves multispectral absorption over the range from ultraviolet to visible light with high response speeds, which provides an effective way to perform high-quality imaging.

14.
Biometrics ; 79(2): 1446-1458, 2023 06.
Article in English | MEDLINE | ID: mdl-35476298

ABSTRACT

Temporal changes exist in clinical trials. Over time, shifts in patients' characteristics, trial conduct, and other features of a clinical trial may occur. In typical randomized clinical trials, temporal effects, that is, the impact of temporal changes on clinical outcomes and study analysis, are largely mitigated by randomization and usually need not be explicitly addressed. However, temporal effects can be a serious obstacle for conducting clinical trials with complex designs, including the adaptive platform trials that are gaining popularity in recent medical product development. In this paper, we introduce a Bayesian robust prior for mitigating temporal effects based on a hidden Markov model, and propose a particle filtering algorithm for computation. We conduct simulation studies to evaluate the performance of the proposed method and provide illustration examples based on trials of Ebola virus disease therapeutics and hemostat in vascular surgery.


Subject(s)
Algorithms , Research Design , Humans , Bayes Theorem , Sample Size , Computer Simulation
15.
J Chem Phys ; 158(17)2023 May 07.
Article in English | MEDLINE | ID: mdl-37125717

ABSTRACT

Organometallic phosphors are an important class of emissive materials used in high-efficiency organic light-emitting devices. However, problems of low photostability arise for blue-emitting phosphors due to chemical and environmental degradation and triplet quenching processes. Various approaches have been developed to improve the photostability of such phosphors, including the design of new organometallic molecules and control of host-dopant composition in thin films. Here, we demonstrate a different approach for improving the photostability of blue organometallic phosphors that uses localized surface plasmon resonances to increase the triplet recombination rate. The increased recombination rate improves the photostability of the phosphor due to the reduction in triplet quenching pathways. We show that the lifetime of phosphorescence is decreased significantly by nanoparticle-based plasmonic surfaces, which improves the photostability of the blue organometallic phosphor by up to a factor of 3.6. Other plasmonic surfaces are also tested and exhibit less significant photostability improvements due to a reduced spectral overlap of the plasmonic modes with the emitter and lower mode confinement. The use of plasmonic surfaces to improve phosphor photostability at blue wavelengths is distinct from other approaches because it involves modification to the local electromagnetic environment of the phosphor rather than modifications to the phosphor molecular structure or the emitting material composition.

16.
Plant Dis ; 107(1): 177-187, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35640950

ABSTRACT

Stem-end rot (SER), caused by Lasiodiplodia theobromae, is one of the most critical diseases of mango in China. The demethylation inhibitor fungicide prochloraz has been widely used in China to control mango diseases. Isolates (n = 139) of L. theobromae were collected in 2019 from six mango-producing regions in Hainan Province, China. The fungicide sensitivity of L. theobromae isolates to prochloraz revealed that the EC50 (50% effective concentration) values ranged from 0.0006 to 16.4131 µg/ml. In total, 21 of the 139 isolates were categorized as resistant to prochloraz. The resistant isolates sprayed with prochloraz could not be effectively controlled in detached fruit. The mycelial growth, conidia germination, and ability to grow at temperatures ranging from 12 to 35°C of resistant isolates decreased, suggesting fitness penalties. The experiment showed that, after treatment with prochloraz at 10 µg/ml, the content of ergosterol in the mycelia of the sensitive isolate decreased by 80.23%, whereas the resistant strain decreased by only 57.52%. The damage to membranes in the sensitive isolates was more serious than for resistant isolates. The target gene CYP51 and the ATP-binding cassette (ABC) subfamily ABCG gene were cloned but no mutation was found. When treated with prochloraz, the expression of CYP51 and ABCG in resistant isolates was significantly higher than in the sensitive isolates. Thus, induced expression of its target gene combined with the induction of expression drug efflux transporters appeared to mediate the prochloraz resistance of L. theobromae.


Subject(s)
Ascomycota , Fungicides, Industrial , Fungicides, Industrial/pharmacology , Ascomycota/genetics , Fruit , China
17.
Pharm Stat ; 22(3): 547-569, 2023.
Article in English | MEDLINE | ID: mdl-36871949

ABSTRACT

In the area of diagnostics, it is common practice to leverage external data to augment a traditional study of diagnostic accuracy consisting of prospectively enrolled subjects to potentially reduce the time and/or cost needed for the performance evaluation of an investigational diagnostic device. However, the statistical methods currently being used for such leveraging may not clearly separate study design and outcome data analysis, and they may not adequately address possible bias due to differences in clinically relevant characteristics between the subjects constituting the traditional study and those constituting the external data. This paper is intended to draw attention in the field of diagnostics to the recently developed propensity score-integrated composite likelihood approach, which originally focused on therapeutic medical products. This approach applies the outcome-free principle to separate study design and outcome data analysis and can mitigate bias due to imbalance in covariates, thereby increasing the interpretability of study results. While this approach was conceived as a statistical tool for the design and analysis of clinical studies for therapeutic medical products, here, we will show how it can also be applied to the evaluation of sensitivity and specificity of an investigational diagnostic device leveraging external data. We consider two common scenarios for the design of a traditional diagnostic device study consisting of prospectively enrolled subjects, which is to be augmented by external data. The reader will be taken through the process of implementing this approach step-by-step following the outcome-free principle that preserves study integrity.


Subject(s)
Likelihood Functions , Humans , Propensity Score , Sensitivity and Specificity
18.
Biom J ; 65(8): e2100357, 2023 12.
Article in English | MEDLINE | ID: mdl-37672794

ABSTRACT

In observational studies, covariates are often confounding factors for treatment assignment. Such covariates need to be adjusted to estimate the causal treatment effect. For observational studies with survival outcomes, it is usually more challenging to adjust for the confounding covariates for causal effect estimation because of censoring. The challenge becomes even thornier when there exists a nonignorable cure fraction in the population. In this paper, we propose a causal effect estimation approach in observational studies for survival data with a cure fraction. We extend the absolute treatment effects on survival outcomes-including the restricted average causal effect and SPCE-to survival outcomes with cure fractions, and construct the corresponding causal effect estimators based on propensity score stratification. We prove the asymptotic properties of the proposed estimators and conduct simulation studies to evaluate their performances. As an illustration, the method is applied to a stomach cancer study.


Subject(s)
Propensity Score , Computer Simulation
19.
Angew Chem Int Ed Engl ; 62(6): e202215737, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36478093

ABSTRACT

Via hydrothermal synthesis of Sn-Al gels, mild dealumination and ion exchange, a bimetallic Sn-Ni-Beta catalyst was prepared which can convert glucose to methyl lactate (MLA) and methyl vinyl glycolate (MVG) in methanol at yields of 71.2 % and 10.2 %, respectively. Results from solid-state magic-angle spinning nuclear magnetic resonance, X-ray photoelectron spectroscopy, transmission electron microscopy, spectroscopic analysis, probe-temperature-programmed desorption, and density functional theory calculations conclusively reveal that the openness of the Sn sites, such as by the formation of [(SiO)3 -Sn-OH] entities, is governed by an adjacent metal cation such as Ni2+ , Co2+ , and Mn2+ . This relies on the low structure-defective pore channel, provided by the current synthesis scheme, and the specific silica hydroxyl anchor point is associated with the incorporation of Sn for additional and precise metal ion localization. The presence of metal cations significantly improved the catalytic performance of Sn-Ni-Beta for glucose isomerization and conversion to MLA of sugar compared with Sn-Beta.

20.
Anal Chem ; 94(35): 12095-12102, 2022 09 06.
Article in English | MEDLINE | ID: mdl-36006461

ABSTRACT

Lipid droplets (LDs), which are ubiquitous organelles existing in almost all eukaryotic cells, have attracted a lot of attention in the field of cell biology over the last decade. For the biological study of LDs via fluorescence imaging, the superior LD fluorescent probes with environmental polarity-sensitive character are highly desired and powerful but are very scarce. Herein, we have newly developed such a kind of fluorescent probe named LDs-Red which enables us to visualize LDs and to further reveal their polarity information. This fluorescent probe displays the advantages of intense red/near-infrared emission, high LD staining specificity, and good photostability; thus, it would be very useful for LD fluorescence imaging application. As a result, the three-dimensional confocal imaging to visualize spatial distribution of LDs and the multicolor confocal imaging to simultaneously observe LDs and other cellular organelles have been realized using this new LD fluorescent probe. Furthermore, the polarity-sensitive emission character of this probe enables us to quantitatively determine the LD polarity via spectral scan imaging. Consequently, the cancer cells (HepG2, HeLa, and Panc02) displaying lower polarity of LDs than the normal cells (L929, U251, and HT22) have been systematically demonstrated. In addition, this polarity-sensitive probe displaying shorter fluorescence wavelengths in cancer cells than in normal cells has an important and potential ability to distinguish them.


Subject(s)
Fluorescent Dyes , Lipid Droplets , HeLa Cells , Humans , Optical Imaging , Staining and Labeling
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