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1.
Cell ; 184(13): 3542-3558.e16, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34051138

RESUMO

Structural variations (SVs) and gene copy number variations (gCNVs) have contributed to crop evolution, domestication, and improvement. Here, we assembled 31 high-quality genomes of genetically diverse rice accessions. Coupling with two existing assemblies, we developed pan-genome-scale genomic resources including a graph-based genome, providing access to rice genomic variations. Specifically, we discovered 171,072 SVs and 25,549 gCNVs and used an Oryza glaberrima assembly to infer the derived states of SVs in the Oryza sativa population. Our analyses of SV formation mechanisms, impacts on gene expression, and distributions among subpopulations illustrate the utility of these resources for understanding how SVs and gCNVs shaped rice environmental adaptation and domestication. Our graph-based genome enabled genome-wide association study (GWAS)-based identification of phenotype-associated genetic variations undetectable when using only SNPs and a single reference assembly. Our work provides rich population-scale resources paired with easy-to-access tools to facilitate rice breeding as well as plant functional genomics and evolutionary biology research.


Assuntos
Ecótipo , Variação Genética , Genoma de Planta , Oryza/genética , Adaptação Fisiológica/genética , Agricultura , Domesticação , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Estrutural do Genoma , Anotação de Sequência Molecular , Fenótipo
2.
Proc Natl Acad Sci U S A ; 120(4): e2209528120, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36649428

RESUMO

Sepsis is a lethal syndrome manifested by an unregulated, overwhelming inflammation from the host in response to infection. Here, we exploit the use of a synthetic heparan sulfate octadecasaccharide (18-mer) to protect against sepsis. The 18-mer not only inhibits the pro-inflammatory activity of extracellular histone H3 and high mobility group box 1 (HMGB1), but also elicits the anti-inflammatory effect from apolipoprotein A-I (ApoA-I). We demonstrate that the 18-mer protects against sepsis-related injury and improves survival in cecal ligation and puncture mice and reduces inflammation in an endotoxemia mouse model. The 18-mer neutralizes the cytotoxic histone-3 (H3) through direct interaction with the protein. Furthermore, the 18-mer enlists the actions of ApoA-I to dissociate the complex of HMGB1 and lipopolysaccharide, a toxic complex contributing to cell death and tissue damage in sepsis. Our study provides strong evidence that the 18-mer mitigates inflammatory damage in sepsis by targeting numerous mediators, setting it apart from other potential therapies with a single target.


Assuntos
Endotoxemia , Proteína HMGB1 , Sepse , Camundongos , Animais , Proteína HMGB1/metabolismo , Apolipoproteína A-I , Sepse/tratamento farmacológico , Sepse/metabolismo , Lipopolissacarídeos , Heparitina Sulfato , Modelos Animais de Doenças
3.
Am J Pathol ; 194(2): 307-320, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38245252

RESUMO

Sleep deprivation (SD) is a global public health burden, and has a detrimental role in the nervous system. Retina is an important part of the central nervous system; however, whether SD affects retinal structures and functions remains largely unknown. Herein, chronic SD mouse model indicated that loss of sleep for 4 months could result in reductions in the visual functions, but without obvious morphologic changes of the retina. Ultrastructural analysis by transmission electron microscope revealed the deterioration of mitochondria, which was accompanied with the decrease of multiple mitochondrial proteins in the retina. Mechanistically, oxidative stress was provoked by chronic SD, which could be ameliorated after rest, and thus restore retinal homeostasis. Moreover, the supplementation of two antioxidants, α-lipoic acid and N-acetyl-l-cysteine, could reduce retinal reactive oxygen species, repair damaged mitochondria, and, as a result, improve the retinal functions. Overall, this work demonstrated the essential roles of sleep in maintaining the integrity and health of the retina. More importantly, it points towards supplementation of antioxidants as an effective intervention strategy for people experiencing sleep shortages.


Assuntos
Privação do Sono , Ácido Tióctico , Humanos , Camundongos , Animais , Privação do Sono/complicações , Privação do Sono/metabolismo , Estresse Oxidativo/fisiologia , Antioxidantes/farmacologia , Retina/metabolismo , Ácido Tióctico/farmacologia , Ácido Tióctico/metabolismo
4.
Cereb Cortex ; 34(3)2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517172

RESUMO

The fetal period is a critical stage in brain development, and understanding the characteristics of the fetal brain is crucial. Although some studies have explored aspects of fetal brain functional networks, few have specifically focused on sex differences in brain network characteristics. We adopted the graph theory method to calculate brain network functional connectivity and topology properties (including global and nodal properties), and further compared the differences in these parameters between male and female fetuses. We found that male fetuses showed an increased clustering coefficient and local efficiency than female fetuses, but no significant group differences concerning other graph parameters and the functional connectivity matrix. Our study suggests the existence of sex-related distinctions in the topological properties of the brain network at the fetal stage of development and demonstrates an increase in brain network separation in male fetuses compared with female fetuses.


Assuntos
Imageamento por Ressonância Magnética , Caracteres Sexuais , Masculino , Humanos , Feminino , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Análise por Conglomerados
5.
Genome Res ; 31(3): 397-410, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33563719

RESUMO

Topologically associating domains (TADs) were recently identified as fundamental units of three-dimensional eukaryotic genomic organization, although our knowledge of the influence of TADs on genome evolution remains preliminary. To study the molecular evolution of TADs in Drosophila species, we constructed a new reference-grade genome assembly and accompanying high-resolution TAD map for D. pseudoobscura Comparison of D. pseudoobscura and D. melanogaster, which are separated by ∼49 million years of divergence, showed that ∼30%-40% of their genomes retain conserved TADs. Comparative genomic analysis of 17 Drosophila species revealed that chromosomal rearrangement breakpoints are enriched at TAD boundaries but depleted within TADs. Additionally, genes within conserved TADs show lower expression divergence than those located in nonconserved TADs. Furthermore, we found that a substantial proportion of long genes (>50 kbp) in D. melanogaster (42%) and D. pseudoobscura (26%) constitute their own TADs, implying transcript structure may be one of the deterministic factors for TAD formation. By using structural variants (SVs) identified from 14 D. melanogaster strains, its three closest sibling species from the D. simulans species complex, and two obscura clade species, we uncovered evidence of selection acting on SVs at TAD boundaries, but with the nature of selection differing between SV types. Deletions are depleted at TAD boundaries in both divergent and polymorphic SVs, suggesting purifying selection, whereas divergent tandem duplications are enriched at TAD boundaries relative to polymorphism, suggesting they are adaptive. Our findings highlight how important TADs are in shaping the acquisition and retention of structural mutations that fundamentally alter genome organization.


Assuntos
Cromatina/química , Cromatina/genética , Drosophila/classificação , Drosophila/genética , Evolução Molecular , Genoma de Inseto/genética , Animais , Drosophila melanogaster/genética , Feminino , Genômica , Masculino
6.
Genome Res ; 31(3): 380-396, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33563718

RESUMO

The rapid evolution of repetitive DNA sequences, including satellite DNA, tandem duplications, and transposable elements, underlies phenotypic evolution and contributes to hybrid incompatibilities between species. However, repetitive genomic regions are fragmented and misassembled in most contemporary genome assemblies. We generated highly contiguous de novo reference genomes for the Drosophila simulans species complex (D. simulans, D. mauritiana, and D. sechellia), which speciated ∼250,000 yr ago. Our assemblies are comparable in contiguity and accuracy to the current D. melanogaster genome, allowing us to directly compare repetitive sequences between these four species. We find that at least 15% of the D. simulans complex species genomes fail to align uniquely to D. melanogaster owing to structural divergence-twice the number of single-nucleotide substitutions. We also find rapid turnover of satellite DNA and extensive structural divergence in heterochromatic regions, whereas the euchromatic gene content is mostly conserved. Despite the overall preservation of gene synteny, euchromatin in each species has been shaped by clade- and species-specific inversions, transposable elements, expansions and contractions of satellite and tRNA tandem arrays, and gene duplications. We also find rapid divergence among Y-linked genes, including copy number variation and recent gene duplications from autosomes. Our assemblies provide a valuable resource for studying genome evolution and its consequences for phenotypic evolution in these genetic model species.


Assuntos
Drosophila simulans/classificação , Drosophila simulans/genética , Evolução Molecular , Genoma de Inseto/genética , Animais , Variações do Número de Cópias de DNA/genética , Elementos de DNA Transponíveis/genética , DNA Satélite/genética , Drosophila melanogaster/genética , Feminino , Masculino
7.
Plant Biotechnol J ; 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735054

RESUMO

The reduction in crop yield caused by pathogens and pests presents a significant challenge to global food security. Genetic engineering, which aims to bolster plant defence mechanisms, emerges as a cost-effective solution for disease control. However, this approach often incurs a growth penalty, known as the growth-defence trade-off. The precise molecular mechanisms governing this phenomenon are still not completely understood, but they generally fall under two main hypotheses: a "passive" redistribution of metabolic resources, or an "active" regulatory choice to optimize plant fitness. Despite the knowledge gaps, considerable practical endeavours are in the process of disentangling growth from defence. The plant microbiome, encompassing both above- and below-ground components, plays a pivotal role in fostering plant growth and resilience to stresses. There is increasing evidence which indicates that plants maintain intimate associations with diverse, specifically selected microbial communities. Meta-analyses have unveiled well-coordinated, two-way communications between plant shoots and roots, showcasing the capacity of plants to actively manage their microbiota for balancing growth with immunity, especially in response to pathogen incursions. This review centers on successes in making use of specific root-associated microbes to mitigate the growth-defence trade-off, emphasizing pivotal advancements in unravelling the mechanisms behind plant growth and defence. These findings illuminate promising avenues for future research and practical applications.

8.
BMC Microbiol ; 24(1): 139, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658841

RESUMO

BACKGROUND: Gastric cancer is one of the global health concerns. A series of studies on the stomach have confirmed the role of the microbiome in shaping gastrointestinal diseases. Delineation of microbiome signatures to distinguish chronic gastritis from gastric cancer will provide a non-invasive preventative and treatment strategy. In this study, we performed whole metagenome shotgun sequencing of fecal samples to enhance the detection of rare bacterial species and increase genome sequence coverage. Additionally, we employed multiple bioinformatics approaches to investigate the potential targets of the microbiome as an indicator of differentiating gastric cancer from chronic gastritis. RESULTS: A total of 65 patients were enrolled, comprising 33 individuals with chronic gastritis and 32 with gastric cancer. Within each group, the chronic gastritis group was sub-grouped into intestinal metaplasia (n = 15) and non-intestinal metaplasia (n = 18); the gastric cancer group, early stage (stages 1 and 2, n = 13) and late stage (stages 3 and 4, n = 19) cancer. No significant differences in alpha and beta diversities were detected among the patient groups. However, in a two-group univariate comparison, higher Fusobacteria abundance was identified in phylum; Fusobacteria presented higher abundance in gastric cancer (LDA scored 4.27, q = 0.041 in LEfSe). Age and sex-adjusted MaAsLin and Random Forest variable of importance (VIMP) analysis in species provided meaningful features; Bacteria_caccae was the most contributing species toward gastric cancer and late-stage cancer (beta:2.43, se:0.891, p:0.008, VIMP score:2.543). In contrast, Bifidobacterium_longum significantly contributed to chronic gastritis (beta:-1.8, se:0.699, p:0.009, VIMP score:1.988). Age, sex, and BMI-adjusted MasAsLin on metabolic pathway analysis showed that GLCMANNANAUT-PWY degradation was higher in gastric cancer and one of the contributing species was Fusobacterium_varium. CONCLUSION: Microbiomes belonging to the pathogenic phylum Fusobacteria and species Bacteroides_caccae and Streptococcus_anginosus can be significant targets for monitoring the progression of gastric cancer. Whereas Bifidobacterium_longum and Lachnospiraceae_bacterium_5_1_63FAA might be protection biomarkers against gastric cancer.


Assuntos
Bactérias , Fezes , Gastrite , Metagenoma , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Gastrite/microbiologia , Fezes/microbiologia , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Idoso , Microbioma Gastrointestinal/genética , Adulto
9.
Exp Dermatol ; 33(1): e15015, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38284203

RESUMO

IMP-3 expression is a poor prognostic factor of melanomas and it promotes melanoma cell migration and invasion by a pathway modulating HMGA2 mRNA expression. We tried to identify other putative targets of IMP-3. We identified putative IMP-3-binding RNAs, including AKT1, MAPK3, RB1 and RELA, by RNA immunoprecipitation coupled with next-generation sequencing. IMP-3 overexpression increased AKT and RELA levels in MeWo cells. siRNAs against AKT1 and RELA inhibited MeWo/Full-length IMP-3 cell migration. IMP-3 knockdown of A2058 cells decreased AKT1 and RELA expression and lowered migration ability. Co-transfection of A2058 cells with AKT1- or RELA-expressing plasmids with IMP-3 siRNA restored the inhibitory effects of IMP-3 knockdown on migration. HMGA2 did not influence AKT1 and RELA expression in melanoma cells. Human melanoma samples with high IMP-3 levels also showed high HMGA2, AKT1 and RELA expression. Our results show that IMP-3 enhances melanoma cell migration through the regulation of the AKT1 and RELA axis.


Assuntos
Melanoma , Proteínas Proto-Oncogênicas c-akt , Proteínas de Ligação a RNA , Fator de Transcrição RelA , Humanos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Melanoma/genética , Melanoma/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
10.
Mov Disord ; 39(1): 152-163, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38014483

RESUMO

BACKGROUND: Hereditary spastic paraplegias (HSP) are neurologic disorders characterized by progressive lower-extremity spasticity. Despite the identification of several HSP-related genes, many patients lack a genetic diagnosis. OBJECTIVES: The aims were to confirm the pathogenic role of biallelic COQ4 mutations in HSP and elucidate the clinical, genetic, and functional molecular features of COQ4-associated HSP. METHODS: Whole exome sequences of 310 index patients with HSP of unknown cause from three distinct populations were analyzed to identify potential HSP causal genes. Clinical data obtained from patients harboring candidate causal mutations were examined. Functional characterization of COQ4 variants was performed using bioinformatic tools, single-cell RNA sequencing, biochemical assays in cell lines, primary fibroblasts, induced pluripotent stem cell-derived pyramidal neurons, and zebrafish. RESULTS: Compound heterozygous variants in COQ4, which cosegregated with HSP in pedigrees, were identified in 7 patients from six unrelated families. Patients from four of the six families presented with pure HSP, whereas probands of the other two families exhibited complicated HSP with epilepsy or with cerebellar ataxia. In patient-derived fibroblasts and COQ4 knockout complementation lines, stable expression of these missense variants exerted loss-of-function effects, including mitochondrial reactive oxygen species accumulation, decreased mitochondrial membrane potential, and lower ubiquinone biosynthesis. Whereas differentiated pyramidal neurons expressed high COQ4 levels, coq4 knockdown zebrafish displayed severe motor dysfunction, reflecting motor neuron dysregulation. CONCLUSIONS: Our study confirms that loss-of-function, compound heterozygous, pathogenic COQ4 variants are causal for autosomal recessive pure and complicated HSP. Moreover, reduced COQ4 levels attributable to variants correspond with decreased ubiquinone biosynthesis, impaired mitochondrial function, and higher phenotypic disease severity. © 2023 International Parkinson and Movement Disorder Society.


Assuntos
Paraplegia Espástica Hereditária , Peixe-Zebra , Animais , Humanos , Ubiquinona/genética , Paraplegia Espástica Hereditária/genética , Mutação/genética , Mutação de Sentido Incorreto , Proteínas Mitocondriais/genética
11.
Pediatr Res ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914760

RESUMO

BACKGROUND: Stuttering affects approximately 5% of children; however, its neurological basis remains unclear. Identifying imaging biomarkers could aid in early detection. Accordingly, we investigated resting-state cerebral blood flow (CBF) in children with developmental stuttering. METHODS: Pulsed arterial spin labelling magnetic resonance imaging was utilised to quantify CBF in 35 children with developmental stuttering and 27 healthy controls. We compared normalised CBF between the two groups and evaluated the correlation between abnormal CBF and clinical indicators. RESULTS: Compared with healthy controls, the stuttering group exhibited decreased normalised CBF in the cerebellum lobule VI bilaterally, right cuneus, and left superior occipital gyrus and increased CBF in the right medial superior frontal gyrus, left rectus, and left dorsolateral superior frontal gyrus. Additionally, normalised CBF in the left cerebellum lobule VI and left superior occipital gyrus was positively correlated with stuttering severity. CONCLUSIONS: Children who stutter display decreased normalised CBF primarily in the cerebellum and occipital gyrus, with increased normalised CBF in the frontal gyrus. Additionally, the abnormal CBF in the left cerebellum lobule VI and left superior occipital gyrus was associated with more severe symptoms, suggesting that decreased CBF in these areas may serve as a novel neuroimaging clue for stuttering. IMPACT: Stuttering occurs in 5% of children and often extends into adulthood, which may negatively affect quality of life. Early detection and treatment are essential. We used pulsed arterial spin labelling magnetic resonance imaging to visualise the resting-state cerebral blood flow (CBF) in children who stutter and healthy children. Normalised CBF was decreased in stutterers in the cerebellum and occipital gyrus and increased in the frontal gyrus. Stuttering severity was linked to abnormal normalised CBF in the left cerebellum lobule VI and left superior occipital gyrus, suggesting that CBF may serve as a novel neuroimaging clue for stuttering.

12.
Crit Rev Food Sci Nutr ; : 1-28, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594966

RESUMO

Oil bodies (OBs) function as organelles that store lipids in plant seeds. An oil body (OB) is encased by a membrane composed of proteins (e.g., oleosins, caleosins, and steroleosins) and a phospholipid monolayer. The distinctive protein-phospholipid membrane architecture of OBs imparts exceptional stability even in extreme environments, thereby sparking increasing interest in their structure and properties. However, a comprehensive understanding of the structure-activity relationships determining the stability and properties of oil bodies requires a more profound exploration of the associated membrane proteins, an aspect that remains relatively unexplored. In this review, we aim to summarize and discuss the structural attributes, biological functions, and properties of OB membrane proteins. From a commercial perspective, an in-depth understanding of the structural and functional properties of OBs is important for the expansion of their applications by producing artificial oil bodies (AOB). Besides exploring their structural intricacies, we describe various methods that are used for purifying and isolating OB membrane proteins. These insights may provide a foundational framework for the practical utilization of OB membrane proteins in diverse applications within the realm of AOB technology, including biological and probiotic delivery, protein purification, enzyme immobilization, astringency detection, and antibody production.

13.
Mol Biol Rep ; 51(1): 520, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625436

RESUMO

BACKGROUND: Mutations in human ether-à-go-go-related gene (hERG) potassium channels are closely associated with long QT syndrome (LQTS). Previous studies have demonstrated that macrolide antibiotics increase the risk of cardiovascular diseases. To date, the mechanisms underlying acquired LQTS remain elusive. METHODS: A novel hERG mutation I1025N was identified in an azithromycin-treated patient with acquired long QT syndrome via Sanger sequencing. The mutant I1025N plasmid was transfected into HEK-293 cells, which were subsequently incubated with azithromycin. The effect of azithromycin and mutant I1025N on the hERG channel was evaluated via western blot, immunofluorescence, and electrophysiology techniques. RESULTS: The protein expression of the mature hERG protein was down-regulated, whereas that of the immature hERG protein was up-regulated in mutant I1025N HEK-293 cells. Azithromycin administration resulted in a negative effect on the maturation of the hERG protein. Additionally, the I1025N mutation exerted an inhibitory effect on hERG channel current. Moreover, azithromycin inhibited hERG channel current in a concentration-dependent manner. The I1025N mutation and azithromycin synergistically decreased hERG channel expression and hERG current. However, the I1025N mutation and azithromycin did not alter channel gating dynamics. CONCLUSIONS: These findings suggest that hERG gene mutations might be involved in the genetic susceptibility mechanism underlying acquired LQTS induced by azithromycin.


Assuntos
Azitromicina , Síndrome do QT Longo , Humanos , Azitromicina/efeitos adversos , Células HEK293 , Antibacterianos/efeitos adversos , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/genética , Mutação
14.
Phys Chem Chem Phys ; 26(2): 788-807, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38088777

RESUMO

Ultrafast excited-state dynamics of the simplest nitrostilbenes, namely trans-4-nitrostilbene (t-NSB), was studied in solvents of various polarities with ultrafast broadband time-resolved fluorescence and transient absorption spectroscopies, and by quantum-chemical computations. The results revealed that the initially excited S1(ππ*) state deactivation dynamics is strongly influenced by the solvent polarity. Specifically, the t-NSB S1-state lifetime decreases by three orders of magnitude from ∼60 ps in high-polarity solvents to ∼60 fs in nonpolar solvents. The strong solvent-polarity dependence arises from the differences in dipole moments among the S1 and relevant states, including the major intersystem crossing (ISC) receiver triplet states, and therefore, the solvent polarity can modulate their relative energies and ISC rates. In nonpolar solvents, the sub-100 fs lifetime is due to a combination of efficient ISC and internal conversion. In medium-polarity solvents, the S1-state population decays via a competing ISC relaxation mechanism in a biphasic manner, and the ISC rates are found to obey the inverse energy gap law of the strong coupling case. In high-polarity solvents, the S1 state is stabilized to a much lower energy such that ISC becomes energetically infeasible, and the S1 state decays via barrier crossing along the torsion angle of the central ethylenic bond to the nonfluorescent perpendicular configuration. Regardless of the initial S1-state deactivation pathways in various solvents, the excited-state population is ultimately trapped in the metastable T1-state perpendicular configuration, at which a slower ISC occurs to bring the system to the ground state and bifurcate into either trans or cis form of NSB.

15.
Phys Chem Chem Phys ; 26(20): 14832-14838, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38721813

RESUMO

Magnetic molecules are promising candidates for quantum information processing (QIP) due to their tunable electron structures and quantum properties. A high spin Co(II) complex, CoH2dota, is studied for its potential to be used as a quantum bit (qubit) utilizing continuous wave (CW) and pulsed electron paramagnetic resonance (EPR) spectroscopy at low temperature. On the X-band microwave energy scale, the system can be treated as an effective spin 1/2 with a strongly anisotropic g-tensor resulting from the significant spin-orbital coupling. An experimental and theoretical study is conducted to investigate the anisotropic Rabi oscillations of the two magnetically equivalent spin centres with different orientations in a single crystal sample, which aims to verify the relationship between the Rabi frequency and the orientation of the g-tensor. The findings of this study show that an effective quantum manipulation method is developed for orthorhombic spin systems.

16.
Phys Chem Chem Phys ; 26(5): 4062-4070, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38224171

RESUMO

Direct access to trans-cis photoisomerization in a metastable state photoacid (mPAH) remains challenging owing to the presence of competing excited-state relaxation pathways and multiple transient isomers with overlapping spectra. Here, we reveal the photoisomerization dynamics in an indazole mPAH using time-resolved fluorescence (TRF) spectroscopy by exploiting a unique property of this mPAH having fluorescence only from the trans isomer. The combination of these experimental results with time-dependent density function theory (TDDFT) calculations enables us to gain mechanistic insight into this key dynamical process.

17.
Int J Med Sci ; 21(1): 107-122, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38164360

RESUMO

NF-κB activation is pivotal for the excess inflammation causing the critical condition and mortality of respiratory viral infection patients. This study was aimed to evaluate the effect of a banana plant extract (BPE) on suppressing NF-κB activity and acute lung inflammatory responses in mice induced by a synthetic double-stranded RNA viral mimetic, polyinosinic-polycytidylic acid (poly (I:C)). The inflammatory responses were analyzed by immunohistochemistry and HE stains and ELISA. The NF-κB activities were detected by immunohistochemistry in vivo and immunofluorescence and Western blot in vitro. Results showed that BPE significantly decreased influx of immune cells (neutrophils, lymphocytes, and total WBC), markedly suppressed the elevation of pro-inflammatory cytokines and chemokines (IL-6, RANTES, IFN-γ, MCP-1, keratinocyte-derived chemokine, and IL-17), and restored the diminished anti-inflammatory IL-10 in the bronchoalveolar lavage fluid (BALF) of poly (I:C)-stimulated mice. Accordingly, HE staining revealed that BPE treatment alleviated poly (I:C)-induced inflammatory cell infiltration and histopathologic changes in mice lungs. Moreover, immunohistochemical analysis showed that BPE reduced the pulmonary IL-6, CD11b (macrophage marker), and nuclear NF-κB p65 staining intensities, whilst restored that of IL-10 in poly (I:C)-stimulated mice. In vitro, BPE antagonized poly(I:C)-induced elevation of IL-6, nitric oxide, reactive oxygen species, NF-κB p65 signaling, and transient activation of p38 MAPK in human lung epithelial-like A549 cells. Taken together, BPE ameliorated viral mimic poly(I:C)-induced acute pulmonary inflammation in mice, evidenced by reduced inflammatory cell infiltration and regulation of both pro- and anti-inflammatory cytokines. The mechanism of action might closely associate with NF-κB signaling inhibition.


Assuntos
Musa , Pneumonia , Camundongos , Humanos , Animais , NF-kappa B , Poli I-C/farmacologia , Poli I-C/uso terapêutico , Interleucina-10 , Interleucina-6 , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Citocinas , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Quimiocinas , Anti-Inflamatórios/uso terapêutico
18.
J Chem Phys ; 160(8)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38421074

RESUMO

Controlling triplet states is crucial to improve the efficiency and lifetime of organic room temperature phosphorescence (ORTP). Although the intrinsic factors from intramolecular radiative and non-radiative decay have been intensively investigated, the extrinsic factors that affect triplet exciton quenching are rarely reported. Diffusion to the defect sites inside the crystal or at the crystal surface may bring about quenching of triplet exciton. Here, the phosphorescence lifetime is found to have a negative correlation with the triplet exciton diffusion coefficient based on the density functional theory (DFT)/time-dependent density functional theory (TD-DFT) calculations on a series of ORTP materials. For systems with a weak charge transfer (CT) characteristic, close π-π stacking will lead to strong triplet coupling and fast triplet exciton diffusion in most cases, which is detrimental to the phosphorescence lifetime. Notably, for intramolcular donor-acceptor (D-A) type systems with a CT characteristic, intermolecular D-A stacking results in ultra-small triplet coupling, thus contributing to slow triplet diffusion and long phosphorescence lifetime. These findings shed some light on molecular design toward high-efficiency long persistent ORTP.

19.
Med Vet Entomol ; 38(1): 99-107, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37715613

RESUMO

Ticks are not only bloodsucking ectoparasites but also important vectors of tick-borne diseases (TBDs), posing significant threats to public and animal health. Domesticated animals serve as critical hosts for numerous ticks, highlighting the importance of understanding tick infestations in Taiwan. To address this knowledge gap, we conducted a nationwide survey to identify ticks on domesticated animals and associated environments in 2018 and 2019. A total of 6,205 ticks were collected from 1,337 host animals, revealing the presence of seven tick species, with Rhipicephalus microplus, and Rhipicephalus sanguineus being the dominant species. High infestation rates and widespread distribution of ticks were observed on domesticated animals, especially on dogs and cattle (yellow cattle and angus cattle), and the neighbouring grassland of yellow cattle. While this study has certain limitations, it provides valuable insights into the distribution and prevalence of ticks on domesticated animals in Taiwan and their implications for controlling TBDs. Further research is needed to comprehensively understand the complex interactions among ticks, hosts and pathogens.


Assuntos
Doenças dos Bovinos , Doenças do Cão , Rhipicephalus , Infestações por Carrapato , Doenças Transmitidas por Carrapatos , Animais , Bovinos , Cães , Animais Domésticos , Taiwan/epidemiologia , Saúde Pública , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Doenças Transmitidas por Carrapatos/veterinária , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças do Cão/parasitologia
20.
Clin Exp Dermatol ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946350

RESUMO

BACKGROUND: Hidradenitis suppurativa (HS) is a chronic inflammatory disorder associated with tunnel formation and scarring. Surgical excision is a potential curative therapy for HS. OBJECTIVES: To characterize the surgical outcomes of patients with HS undergoing complete excision and to identify the risk factors associated with postoperative recurrence. METHODS: This retrospective 16-year cohort study enrolled patients 20 years or older who underwent complete excision for HS lesions at the National Taiwan University Hospital. We assessed the rates of postsurgical recurrence and complications, and estimated the odds ratio (ORs) with 95% confidence intervals (CIs) of their association with potential risk factors using generalized estimating equations. RESULTS: In total, 136 patients with HS and the 284 corresponding complete excisions were identified. Recurrence developed in 88 (31.0%) operations, while complications occurred in 102 (35.9%). Common types of complications included wound dehiscence, hypertrophic scars, and surgical site infection. Clinical factors associated with a lower risk of recurrence were male sex (aOR, 0.48; 95% CI, 0.23-0.98), operation at atypical locations (aOR, 0.28; 95% CI, 0.08-0.99), and wound repair by split-thickness skin graft (aOR, 0.31; 95% CI, 0.12-0.77). Wound dehiscence was associated with an increased risk of recurrence (aOR, 2.55; 95% CI, 1.21-5.42). No independent factors were identified as being associated with composite postoperative complications. CONCLUSIONS: Complete excision alone is effective in curing HS in Asians. Recurrence developed in about one-third of the complete excisions performed for HS. Sex, operative locations, methods of wound repair, and wound dehiscence were major determinants for recurrence.

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