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1.
Nature ; 597(7878): 688-692, 2021 09.
Article in English | MEDLINE | ID: mdl-34497416

ABSTRACT

Mechanisms that favour rare species are key to the maintenance of diverse communities1-3. One of the most critical tasks for conservation of flowering plant biodiversity is to understand how plant-pollinator interactions contribute to the maintenance of rare species4-7. Here we show that niche partitioning in pollinator use and asymmetric facilitation confer fitness advantage of rarer species in a biodiversity hotspot using phylogenetic structural equation modelling that integrates plant-pollinator and interspecific pollen transfer networks with floral functional traits. Co-flowering species filtered pollinators via floral traits, and rarer species showed greater pollinator specialization leading to higher pollination-mediated male and female fitness than more abundant species. When plants shared pollinator resources, asymmetric facilitation via pollen transport dynamics benefitted the rarer species at the cost of more abundant species, serving as an alternative diversity-promoting mechanism. Our results emphasize the importance of community-wide plant-pollinator interactions that affect reproduction for biodiversity maintenance.


Subject(s)
Biodiversity , Magnoliopsida/classification , Pollination , Animals , California , Ecosystem , Flowers/anatomy & histology , Genetic Fitness , Insecta , Models, Biological , Phylogeny , Pollen
2.
Blood ; 143(1): 32-41, 2024 01 04.
Article in English | MEDLINE | ID: mdl-37824804

ABSTRACT

ABSTRACT: Chronic active Epstein-Barr virus (EBV) disease (CAEBV) is a lethal syndrome because of persistent EBV infection. When diagnosed as CAEBV, EBV infection was observed in multiple hematopoietic lineages, but the etiology of CAEBV is still elusive. Bone marrow and peripheral cells derived from 5 patients with CAEBV, 1 patient with EBV-associated hemophagocytic lymphohistiocytosis, and 2 healthy controls were analyzed. Multiple assays were applied to identify and characterize EBV-infected cells, including quantitative polymerase chain reaction, PrimeFlow, and single-cell RNA-sequencing (scRNA-seq). Based on scRNA-seq data, alterations in gene expression of particular cell types were analyzed between patients with CAEBV and controls, and between infected and uninfected cells. One patient with CAEBV was treated with allogeneic hematopoietic stem cell transplantation (HSCT), and the samples derived from this patient were analyzed again 6 months after HSCT. EBV infected the full spectrum of the hematopoietic system including both lymphoid and myeloid lineages, as well as the hematopoietic stem cells (HSCs) of the patients with CAEBV. EBV-infected HSCs exhibited a higher differentiation rate toward downstream lineages, and the EBV infection had an impact on both the innate and adaptive immunity, resulting in inflammatory symptoms. EBV-infected cells were thoroughly removed from the hematopoietic system after HSCT. Taken together, multiple lines of evidence presented in this study suggest that CAEBV disease originates from the infected HSCs, which might potentially lead to innovative therapy strategies for CAEBV.


Subject(s)
Epstein-Barr Virus Infections , Lymphohistiocytosis, Hemophagocytic , Humans , Herpesvirus 4, Human/genetics , Chronic Disease , Lymphohistiocytosis, Hemophagocytic/complications , Hematopoietic Stem Cells
3.
Immunity ; 46(3): 474-487, 2017 03 21.
Article in English | MEDLINE | ID: mdl-28314594

ABSTRACT

Brain ischemia inhibits immune function systemically, with resulting infectious complications. Whether in stroke different immune alterations occur in brain and periphery and whether analogous mechanisms operate in these compartments remains unclear. Here we show that in patients with ischemic stroke and in mice subjected to middle cerebral artery occlusion, natural killer (NK) cells display remarkably distinct temporal and transcriptome profiles in the brain as compared to the periphery. The activation of catecholaminergic and hypothalamic-pituitary-adrenal axis leads to splenic atrophy and contraction of NK cell numbers in the periphery through a modulated expression of SOCS3, whereas cholinergic innervation-mediated suppression of NK cell responses in the brain involves RUNX3. Importantly, pharmacological or genetic ablation of innervation preserved NK cell function and restrained post-stroke infection. Thus, brain ischemia compromises NK cell-mediated immune defenses through mechanisms that differ in the brain versus the periphery, and targeted inhibition of neurogenic innervation limits post-stroke infection.


Subject(s)
Brain Ischemia/immunology , Brain/immunology , Killer Cells, Natural/immunology , Spleen/immunology , Aged , Animals , Brain Ischemia/complications , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Gene Expression Profiling , Humans , Infections/etiology , Infections/immunology , Male , Mice , Mice, Inbred C57BL , Real-Time Polymerase Chain Reaction , Transcriptome
4.
Proc Natl Acad Sci U S A ; 120(18): e2216342120, 2023 05 02.
Article in English | MEDLINE | ID: mdl-37098070

ABSTRACT

NKG2D (natural-killer group 2, member D) is a homodimeric transmembrane receptor that plays an important role in NK, γδ+, and CD8+ T cell-mediated immune responses to environmental stressors such as viral or bacterial infections and oxidative stress. However, aberrant NKG2D signaling has also been associated with chronic inflammatory and autoimmune diseases, and as such NKG2D is thought to be an attractive target for immune intervention. Here, we describe a comprehensive small-molecule hit identification strategy and two distinct series of protein-protein interaction inhibitors of NKG2D. Although the hits are chemically distinct, they share a unique allosteric mechanism of disrupting ligand binding by accessing a cryptic pocket and causing the two monomers of the NKG2D dimer to open apart and twist relative to one another. Leveraging a suite of biochemical and cell-based assays coupled with structure-based drug design, we established tractable structure-activity relationships with one of the chemical series and successfully improved both the potency and physicochemical properties. Together, we demonstrate that it is possible, albeit challenging, to disrupt the interaction between NKG2D and multiple protein ligands with a single molecule through allosteric modulation of the NKG2D receptor dimer/ligand interface.


Subject(s)
Killer Cells, Natural , NK Cell Lectin-Like Receptor Subfamily K , Ligands , CD8-Positive T-Lymphocytes , Protein Binding
5.
J Biol Chem ; 300(10): 107756, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39260699

ABSTRACT

Aminoacyl-tRNA synthetases are fundamental to the translation machinery with emerging roles in transcriptional regulation. Previous cellular studies have demonstrated tyrosyl-tRNA synthetase (YARS1 or TyrRS) as a stress response protein through its cytosol-nucleus translocation to maintain cellular homeostasis. Here, we established a mouse model with a disrupted TyrRS nuclear localization signal, revealing its systemic impact on metabolism. Nuclear TyrRS deficiency (YarsΔNLS) led to reduced lean mass, reflecting a mild developmental defect, and reduced fat mass, possibly due to increased energy expenditure. Consistently, YarsΔNLS mice exhibit improved insulin sensitivity and reduced insulin levels, yet maintain normoglycemia, indicative of enhanced insulin action. Notably, YarsΔNLS mice also develop progressive hearing loss. These findings underscore the crucial function of nuclear TyrRS in the maintenance of fat storage and hearing and suggest that aminoacyl-tRNA synthetases' regulatory roles can affect metabolic pathways and tissue-specific health. This work broadens our understanding of how protein synthesis interconnects metabolic regulation to ensure energy efficiency.

6.
Proc Biol Sci ; 291(2023): 20240612, 2024 May.
Article in English | MEDLINE | ID: mdl-38772419

ABSTRACT

Plant microbiomes that comprise diverse microorganisms, including prokaryotes, eukaryotes and viruses, are the key determinants of plant population dynamics and ecosystem function. Despite their importance, little is known about how species interactions (especially trophic interactions) between microbes from different domains modify the importance of microbiomes for plant hosts and ecosystems. Using the common duckweed Lemna minor, we experimentally examined the effects of predation (by bacterivorous protists) and parasitism (by bacteriophages) within microbiomes on plant population size and ecosystem phosphorus removal. Our results revealed that the addition of predators increased plant population size and phosphorus removal, whereas the addition of parasites showed the opposite pattern. The structural equation modelling further pointed out that predation and parasitism affected plant population size and ecosystem function via distinct mechanisms that were both mediated by microbiomes. Our results highlight the importance of understanding microbial trophic interactions for predicting the outcomes and ecosystem impacts of plant-microbiome symbiosis.


Subject(s)
Araceae , Bacteria , Microbial Interactions , Microbiota , Araceae/microbiology , Araceae/physiology , Symbiosis , Phosphorus/metabolism , Bacteria/virology , Eukaryota/physiology , Bacteriophages/physiology
7.
Appl Environ Microbiol ; 90(8): e0085024, 2024 08 21.
Article in English | MEDLINE | ID: mdl-39016614

ABSTRACT

Viral communities exist in a variety of ecosystems and play significant roles in mediating biogeochemical processes, whereas viruses inhabiting strongly alkaline geochemical systems remain underexplored. In this study, the viral diversity, potential functionalities, and virus-host interactions in a strongly alkaline environment (pH = 10.4-12.4) exposed to the leachates derived from the serpentinization-like reactions of smelting slags were investigated. The viral populations (e.g., Herelleviridae, Queuovirinae, and Inoviridae) were closely associated with the dominating prokaryotic hosts (e.g., Meiothermus, Trueperaceae, and Serpentinomonas) in this ultrabasic environment. Auxiliary metabolic genes (AMGs) suggested that viruses may enhance hosts' fitness by facilitating cofactor biosynthesis, hydrogen metabolism, and carbon cycling. To evaluate the activity of synthesis of essential cofactor vitamin B9 by the viruses, a viral folA (vfolA) gene encoding dihydrofolate reductase (DHFR) was introduced into a thymidine-auxotrophic strain Escherichia coli MG1655 ΔfolA mutant, which restored the growth of the latter in the absence of thymidine. Notably, the homologs of the validated vDHFR were globally distributed in the viromes across various ecosystems. The present study sheds new light on the unique viral communities in hyperalkaline ecosystems and their potential beneficial impacts on the coexisting microbial consortia by supplying essential cofactors. IMPORTANCE: This study presents a comprehensive investigation into the diversity, potential functionalities, and virus-microbe interactions in an artificially induced strongly alkaline environment. Functional validation of the detected viral folA genes encoding dihydrofolate reductase substantiated the synthesis of essential cofactors by viruses, which may be ubiquitous, considering the broad distribution of the viral genes associated with folate cycling.


Subject(s)
Microbiota , Hydrogen-Ion Concentration , Virome/genetics , Viruses/genetics , Escherichia coli/genetics , Escherichia coli/metabolism , Tetrahydrofolate Dehydrogenase/genetics , Tetrahydrofolate Dehydrogenase/metabolism , Bacteria/genetics , Bacteria/metabolism , Bacteria/classification
8.
Cancer Invest ; 42(6): 527-537, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38965994

ABSTRACT

Despite the emergence of various treatment strategies for rectal cancer based on neoadjuvant chemoradiotherapy, there is currently a lack of reliable biomarkers to determine which patients will respond well to neoadjuvant chemoradiotherapy. Through collecting hematological and biochemical parameters data of patients prior to receiving neoadjuvant chemoradiotherapy, we evaluated the predictive value of systemic inflammatory indices for pathological response and prognosis in rectal cancer patients. We found that baseline GRIm-Score was an independent predictor for MPR in rectal cancer patients. However, no association was observed between several commonly systemic inflammation indices and long-term outcome.


Subject(s)
Neoadjuvant Therapy , Rectal Neoplasms , Humans , Rectal Neoplasms/pathology , Rectal Neoplasms/therapy , Rectal Neoplasms/immunology , Male , Female , Middle Aged , Neoadjuvant Therapy/methods , Aged , Chemoembolization, Therapeutic/methods , Prognosis , Treatment Outcome , Adult , Chemoradiotherapy/methods
9.
Chemistry ; 30(32): e202401108, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38567703

ABSTRACT

Sialyl-Lewisx (SLex) is involved in immune regulation, human fertilization, cancer, and bacterial and viral diseases. The influence of the complex glycan structures, which can present SLex epitopes, on binding is largely unknown. We report here a chemoenzymatic strategy for the preparation of a panel of twenty-two isomeric asymmetrical tri-antennary N-glycans presenting SLex-Lex epitopes on either the MGAT4 or MGAT5 arm that include putative high-affinity ligands for E-selectin. The N-glycans were prepared starting from a sialoglycopeptide isolated from egg yolk powder and took advantage of inherent substrate preferences of glycosyltransferases and the use of 5'-diphospho-N-trifluoracetylglucosamine (UDP-GlcNHTFA) that can be transferred by branching N-acetylglucosaminyltransferases to give, after base treatment, GlcNH2-containing glycans that temporarily disable an antenna from enzymatic modification. Glycan microarray binding studies showed that E-selectin bound equally well to linear glycans and tri-antennary N-glycans presenting SLex-Lex. On the other hand, it was found that hemagglutinins (HA) of H5 influenza A viruses (IAV) preferentially bound the tri-antennary N-glycans. Furthermore, several H5 HAs preferentially bound to N-glycan presenting SLex on the MGAT4 arm. SLex is displayed in the respiratory tract of several avian species, demonstrating the relevance of investigating the binding of, among others IAVs, to complex N-glycans presenting SLex.


Subject(s)
E-Selectin , Influenza A virus , Polysaccharides , Sialyl Lewis X Antigen , Polysaccharides/chemistry , Polysaccharides/metabolism , Influenza A virus/metabolism , Sialyl Lewis X Antigen/metabolism , Sialyl Lewis X Antigen/chemistry , E-Selectin/metabolism , E-Selectin/chemistry , Humans , Oligosaccharides/chemistry , Oligosaccharides/chemical synthesis , Oligosaccharides/metabolism , Receptors, Virus/metabolism , Receptors, Virus/chemistry , Epitopes/chemistry , Epitopes/metabolism , Animals
10.
Mol Cell Biochem ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38967721

ABSTRACT

Extracellular vesicles (EVs) produced from MSCs were currently considered as a novel therapeutic agent for skin tissue regeneration and repair. Preconditioning stem cells may activate more molecular pathways and release more bioactive agents. In this study, we obtained EVs from normal (N-EVs) and serum- and glucose-deprived (SGD-EVs) human umbilical cord mesenchymal stem cells (HUCMSCs), and showed that SGD-EVs promoted the migration, proliferation, and tube formation of HUVECs in vitro. In vivo experiments utilizing a rat model show that both N-EVs and SGD-EVs boosted angiogenesis of skin defects and accelerated skin wound healing, while treating wounds with SGD-EVs led to faster skin healing and enhanced angiogenesis. miRNA sequencing showed that miR-29a-3p was abundant in SGD-EVs, and overexpressing miR-29a-3p enhanced the angiogenic ability of HUVECs, while inhibiting miR-29a-3p presented the opposite effect. Further studies demonstrated that miR-29a-3p directly targeted CTNNBIP1, which mediated angiogenesis of HUCMSCs-derived EVs through inhibiting CTNNBIP1 to activate Wnt/ß-catenin signaling pathway. Taken together, these findings suggested that SGD-EVs promote angiogenesis via transferring miR-29a-3p, and activation of Wnt/ß-catenin signaling pathway played a crucial role in SGD-EVs-induced VEGFA production during wound angiogenesis. Our results offered a new avenue for modifying EVs to enhance tissue angiogenesis and augment its role in skin repair.

11.
Am J Bot ; 111(8): e16287, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38366679

ABSTRACT

PREMISE: Whole-genome duplication (neopolyploidy) can instantly differentiate the phenotype of neopolyploids from their diploid progenitors. These phenotypic shifts in organs such as roots and leaves could also differentiate the way neopolyploids interact with microbial species. While some studies have addressed how specific microbial interactions are affected by neopolyploidy, we lack an understanding of how genome duplication affects the diversity and composition of microbial communities. METHODS: We performed a common garden experiment with multiple clones of artificially synthesized autotetraploids and their ancestral diploids, derived from 13 genotypes of wild strawberry, Fragaria vesca. We sequenced epiphytic bacteria and fungi from roots and leaves and characterized microbial communities and leaf functional traits. RESULTS: Autotetraploidy had no effect on bacterial alpha diversity of either organ, but it did have a genotype-dependent effect on the diversity of fungi on leaves. In contrast, autotetraploidy restructured the community composition of leaf bacteria and had a genotype-dependent effect on fungal community composition in both organs. The most differentially abundant bacterial taxon on leaves belonged to the Sphingomonas, while a member of the Trichoderma was the most differentially abundant fungal taxon on roots. Ploidy-induced change in leaf size was strongly correlated with a change in bacterial but not fungal leaf communities. CONCLUSIONS: Genome duplication can immediately alter aspects of the plant microbiome, but this effect varies by host genotype and bacterial and fungal community. Expanding these studies to wild settings where plants are exposed continuously to microbes are needed to confirm the patterns observed here.


Subject(s)
Bacteria , Fragaria , Fungi , Microbiota , Plant Leaves , Plant Roots , Fragaria/microbiology , Fragaria/genetics , Plant Leaves/microbiology , Bacteria/genetics , Bacteria/classification , Plant Roots/microbiology , Fungi/genetics , Fungi/physiology , Polyploidy , Genotype , Biodiversity
12.
Article in English | MEDLINE | ID: mdl-39438281

ABSTRACT

OBJECTIVES: To investigate the diagnostic performance of Node Reporting and Data System (Node-RADS) combined with computed tomography (CT) radiomics for assessing nonenlargement regional lymph nodes in gastric cancer (GC). METHODS: Preoperative CT images were retrospectively collected from 376 pathologically confirmed of gastric adenocarcinoma from January 2019 to December 2023, with 605 lymph nodes included for analysis. They were divided into training (n = 362) and validation (n = 243) sets. Radiomics features were extracted from venous-phase, and the radiomics score was obtained. Clinical information, CT parameters, and Node-RADS classification were collected. A combined model was built using machine-learning approach and tested in validation set using receiver operating characteristic curve analysis. Further validation was conducted in different subgroups of lymph node short-axis diameter (SD) range. RESULTS: Node-RADS score, SD, maximum diameter of thickness of tumor, and radiomics were identified as the most predictive factors. The results demonstrated that the integrated model combining SD, maximum diameter of thickness of tumor, Node-RADS, and radiomics outperformed the model excluding radiomics, yielding an area under the receiver operating characteristic curve of 0.82 compared with 0.79, with a statistically significant difference (P < 0.001). Subgroup analysis based on different SDs of lymph nodes also revealed enhanced diagnostic accuracy when incorporating the radiomics score for the 4- to 7.9-mm subgroups, all P < 0.05. However, for the 8- to 9.9-mm subgroup, the combination of the radiomics did not significantly improve the prediction, with an area under the receiver operating characteristic curve of 0.85 versus 0.85, P = 0.877. CONCLUSION: The integration of radiomics scores with Node-RADS assessments significantly enhances the accuracy of lymph node metastasis evaluation for GC. This combined model is particularly effective for lymph nodes with smaller standard deviations, yielding a marked improvement in diagnostic precision. CLINICAL RELEVANCE STATEMENT: The findings of this study indicate that a composite model, which incorporates Node-RADS, radiomics features, and conventional parameters, may serve as an effective method for the assessment of nonenlarged lymph nodes in GC.

13.
Neurol Sci ; 45(5): 2191-2197, 2024 May.
Article in English | MEDLINE | ID: mdl-37982973

ABSTRACT

BACKGROUND: Very late-onset neuromyelitis optica spectrum disorder-related optic neuritis is limited to a few case reports. OBJECTIVE: To investigate the clinical features and visual prognosis of very late-onset neuromyelitis optica spectrum disorder-related optic neuritis. METHODS: This study evaluated 22 patients with first-onset optic neuritis and fulfilled the 2015 diagnosis criteria for neuromyelitis optica spectrum disorders. RESULTS: The mean age at optic neuritis onset was 73.91 ± 4.71 (range: 70-82) years with a female predominance (81.8%; ratio: 4.5:1). Antinuclear antibody seropositivity and seronegativity were identified in 12 (55.5%) and 10 (45.5%) patients, respectively. Severe visual loss persisted in 19 (19/42, 45.3%) eyes at the last follow-up. Although patients with antinuclear antibody seropositivity had a significantly higher frequency of attacks (P = 0.015), but they had a longer median time to reach severe visual loss (37 vs. 26 months; log-rank test, P = 0.023). Multivariate logistic regression analysis revealed antinuclear antibody seropositivity (hazard ratio = 4.849, 95% confidence interval: 1.309-17.965, P = 0.018) as a good predictor of visual acuity improvement. CONCLUSION: Patients with very late-onset neuromyelitis optica spectrum disorder-related optic neuritis may develop severe optic neuritis, and those with antinuclear antibody seronegativity have a similar clinical presentation but worse outcome than those with seropositivity.


Subject(s)
Neuromyelitis Optica , Optic Neuritis , Humans , Female , Aged , Aged, 80 and over , Male , Neuromyelitis Optica/diagnosis , Antibodies, Antinuclear , Optic Neuritis/diagnosis , Prognosis , Eye , Aquaporin 4 , Retrospective Studies
14.
Oral Dis ; 2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39039759

ABSTRACT

OBJECTIVES: Periodontitis is a common oral disease that is aggravated by occlusal trauma. Fibrin is a protein that participates in blood clotting and is involved in several human diseases. The deposition of fibrin in periodontal tissues can induce periodontitis, while mechanical forces may regulate the degradation of fibrin. Our study investigated how occlusal trauma aggravating periodontitis through regulating the plasminogen/plasmin system and fibrin deposition. MATERIALS AND METHODS: This study included 84 C57BL/6 mice in which periodontitis was induced with or without occlusal trauma. Micro-computed tomography was used to assess bone resorption. Fibrin, fibrinogen, plasminogen, plasmin, tissue plasminogen activator (t-PA), and urokinase plasminogen activator (u-PA) levels were measured using Frazer-Lendrum staining, quantitative reverse transcription polymerase chain reaction, enzyme-linked immunosorbent assay, western blotting, immunofluorescence staining, and immunohistochemistry staining. RESULTS: Occlusal trauma aggravated inflammation and bone resorption. The periodontitis group showed significant fibrin deposition. Occlusal trauma increased fibrin deposition and neutrophil aggregation. The periodontitis with occlusal trauma group had decreased fibrinogen, t-PA, and u-PA expression and plasmin and fibrin degradation product levels, as well as increased plasminogen levels. CONCLUSION: Occlusal trauma promotes excessive fibrin deposition by suppressing the plasminogen/plasmin system, thus exacerbating periodontitis.

15.
BMC Ophthalmol ; 24(1): 237, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38844903

ABSTRACT

BACKGROUND: The purpose of this study was to investigate the photoprotection effect of peroxiredoxin 1 (PRDX1) protein in ultraviolet B (UVB) irradiation-induced damage of retinal pigment epithelium (RPE) and its possible molecular mechanism. METHODS: ARPE-19 cell viability and apoptosis were assessed by MTT assay and flow cytometry, respectively. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the PRDX1 expression. The corresponding kits were employed to measure the levels or activities of lactate dehydrogenase (LDH), 8-hydroxy-2-deoxyguanosine (8-OHdG), reactive oxygen species (ROS), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD). Western blotting was applied to examine PRDX1 expression and mitogen-activated protein kinase (MAPK) signaling pathway-related proteins. RESULTS: After exposure to 20 mJ/cm2 intensity of UVB irradiation for 24 h, ARPE-19 cells viability was decreased, the leakage degree of LDH and 8-OHdG were increased, and cell apoptosis was elevated. The expression of PRDX1 was significantly down-regulated in UVB-induced ARPE-19 cells. The low expression of PRDX1 was involved in high irradiation intensity. Overexpression of PRDX1 increased cell activity, decreased cell apoptosis, and LDH as well as 8-OHdG leakage in UVB-induced ARPE-19 cells. In addition to alleviating UVB-induced cell damage, PRDX1 overexpression also inhibited UVB-induced oxidative stress (down-regulation of ROS and MDA levels, up-regulation of GSH-Px and SOD activities) and the activation of MAPK signaling pathway in ARPE-19 cells. CONCLUSION: PRDX1 exerts a photoprotection effect on RPE by attenuating UVB-induced cell damage and inhibiting oxidative stress, which can be attributed to the inhibition of MAPK signaling pathway activation.


Subject(s)
Apoptosis , Cell Survival , Oxidative Stress , Peroxiredoxins , Reactive Oxygen Species , Retinal Pigment Epithelium , Ultraviolet Rays , Humans , Retinal Pigment Epithelium/radiation effects , Retinal Pigment Epithelium/metabolism , Peroxiredoxins/metabolism , Ultraviolet Rays/adverse effects , Reactive Oxygen Species/metabolism , MAP Kinase Signaling System/physiology , Cell Line , Blotting, Western , Cells, Cultured , 8-Hydroxy-2'-Deoxyguanosine/metabolism , Signal Transduction
16.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Article in English | MEDLINE | ID: mdl-33753480

ABSTRACT

Through dominant mutations, aminoacyl-tRNA synthetases constitute the largest protein family linked to Charcot-Marie-Tooth disease (CMT). An example is CMT subtype 2N (CMT2N), caused by individual mutations spread out in AlaRS, including three in the aminoacylation domain, thereby suggesting a role for a tRNA-charging defect. However, here we found that two are aminoacylation defective but that the most widely distributed R329H is normal as a purified protein in vitro and in unfractionated patient cell samples. Remarkably, in contrast to wild-type (WT) AlaRS, all three mutant proteins gained the ability to interact with neuropilin 1 (Nrp1), the receptor previously linked to CMT pathogenesis in GlyRS. The aberrant AlaRS-Nrp1 interaction is further confirmed in patient samples carrying the R329H mutation. However, CMT2N mutations outside the aminoacylation domain do not induce the Nrp1 interaction. Detailed biochemical and biophysical investigations, including X-ray crystallography, small-angle X-ray scattering, hydrogen-deuterium exchange (HDX), switchSENSE hydrodynamic diameter determinations, and protease digestions reveal a mutation-induced structural loosening of the aminoacylation domain that correlates with the Nrp1 interaction. The b1b2 domains of Nrp1 are responsible for the interaction with R329H AlaRS. The results suggest Nrp1 is more broadly associated with CMT-associated members of the tRNA synthetase family. Moreover, we revealed a distinct structural loosening effect induced by a mutation in the editing domain and a lack of conformational impact with C-Ala domain mutations, indicating mutations in the same protein may cause neuropathy through different mechanisms. Our results show that, as with other CMT-associated tRNA synthetases, aminoacylation per se is not relevant to the pathology.


Subject(s)
Alanine-tRNA Ligase/metabolism , Charcot-Marie-Tooth Disease/genetics , Neuropilin-1/metabolism , Alanine-tRNA Ligase/chemistry , Alanine-tRNA Ligase/genetics , Aminoacylation/genetics , Cells, Cultured , Charcot-Marie-Tooth Disease/blood , Crystallography, X-Ray , Deuterium Exchange Measurement , Humans , Lymphocytes , Mutation , Neuropilin-1/genetics , Primary Cell Culture , Protein Binding/genetics , Protein Domains/genetics , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Recombinant Proteins/ultrastructure , Scattering, Small Angle
17.
Altern Ther Health Med ; 30(1): 122-128, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37773655

ABSTRACT

Objective: To explore whether contrast-enhanced ultrasound (CEUS) can improve tubal ectopic pregnancy detection rate, tubal dilation, tubal hematoma, and gestational sac. Methods: This retrospective study included 34 patients with suspected ectopic pregnancy who underwent contrast-enhanced ultrasound at Dongzhimen Hospital of Beijing University of Chinese Medicine between March 2021 and September 2016. Of these, 27 patients were confirmed to have tubal pregnancy by laparoscopic surgery and histopathology. Four ultrasound physicians (2 experts and 2 non-experts) conducted a retrospective analysis of conventional color Doppler ultrasound and the combination of conventional color Doppler ultrasound with contrast-enhanced ultrasound (color Doppler ultrasound + CEUS). They analyzed the differences in confidence levels and reproducibility in identifying tubal dilation, tubal hematoma, and gestational sac implantation sites. Additionally, the characteristic features of ectopic pregnancy on contrast-enhanced ultrasound were summarized, including gestational sac morphology, triple ring sign, enhancement patterns (branching or punctate), tubal dilation (with or without hematoma), contrast enhancement of tubal walls, and presence of free fluid. Results: In the expert group, the correct identification rate of the gestational sac implantation site on ultrasound images increased from 13/34 (38.2%) with conventional color Doppler ultrasound to 20/34 (58.8%) with color Doppler ultrasound + CEUS, the differences were statistically significant (38.2% vs. 58.8%, P = .039). The correct identification rate of tubal dilation increased from 6/34 (17.7%) to 25/34 (73.5%) (P = .001), and the correct identification rate of tubal hematoma increased from 3/34 (8.8%) to 17/34 (50.0%) with color Doppler ultrasound + CEUS (P < .001). In the non-expert group, the correct identification rate of the gestational sac implantation site increased from 8/24 (23.5%) with conventional ultrasound to 19/34 (55.9%) with ultrasound + CEUS (P = .003). The correct identification rate of tubal dilation increased from 6/34 (17.7%) to 23/34 (67.7%) (P < .001), and the correct identification rate of tubal hematoma increased from 3/34 (8.82%) to 12/34 (35.3%) with color Doppler ultrasound + CEUS (P = .012). Conclusion: The analysis of contrast-enhanced ultrasound images provides characteristic features and diagnostic points for tubal ectopic pregnancy, including gestational sac, thick ring sign, tubal dilation, and tubal dilation with hematoma. This approach improves the accuracy of partial pregnancy of unknown location (PUL) diagnosis and reduces the technical dependence on ultrasound personnel.


Subject(s)
Pregnancy, Ectopic , Pregnancy, Tubal , Pregnancy , Female , Humans , Retrospective Studies , Reproducibility of Results , Pregnancy, Tubal/diagnostic imaging , Pregnancy, Ectopic/diagnostic imaging , Treatment Outcome , Hematoma
18.
Lasers Med Sci ; 39(1): 89, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38453744

ABSTRACT

Various treatment modalities have been applied to atrophic scars. Fractional CO2 laser treatment has attracted increasingly more attention because of its quicker recovery time and fewer side effects. However, its limitation of sculpting the edge is an urgent shortcoming. In order to achieve a more effective result with fewer complications, we have integrated ultrapulse CO2 and fractional CO2 lasers to for the treatment of facial atrophic scars. The study included 25 patients (10 males and 15 females) diagnosed with moderate to severe atrophic scars between August 2020 and July 2022. All subjects underwent the same surgical treatment. The effects were assessed at baseline, 1 week, 1 month, and 3 months using photographic evidence. Objective evaluation of the results was conducted using a quartile grading scale, while the subjects' satisfaction and any adverse events were also recorded. The patients in the study underwent more than two laser sessions (2-5), resulting in substantial improvement in their appearance. The time interval between each session was 3-6 months. The majority of the patients (19/25, 76%) had a significant or even excellent improvement. Any adverse events observed, such as erythema, superficial crusting, and PIH, were of a mild nature and temporary in duration. This treatment combined two CO2 lasers is an effective and safe choice for atrophic scars in Asians.


Subject(s)
Acne Vulgaris , Lasers, Gas , Male , Female , Humans , Cicatrix/pathology , Carbon Dioxide , Treatment Outcome , Acne Vulgaris/complications , Erythema/etiology , Lasers, Gas/therapeutic use , Atrophy/complications
19.
Rev Esp Enferm Dig ; 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38832596

ABSTRACT

The inverted hyperplastic polyp (IHP) is known as hyperplastic gastric mucosa growth into submucosa and endoscopically presented as sessile or pedunculated submucosa lesion. It occurs in between 3.1% to 20.1% of cases, while its malignant transformation rate is just 0.02%. A male underwent esophagogastroduodenoscopy (EGD) and discovered a submucosal lesion with a pinhole-like orifice in the fundus. And endoscopic ultrasound (EUS) showed it was a heterogenous hypoechoic lesion located in the submucosa. After endoscopic resection, the pathological findings and immunohistochemical staining revealed it was inverted hyperplastic polyp (IHP) with adenocarcinoma. The measurement of the cancerous IHP depth of invasion is controversial. Thus, how to define the depth of lesion invasion in this patient needs to be seriously considered. To manage IHP with adenocarcinoma better, the depth of lesion invasion cancerous IHP needs to be seriously considered.

20.
Carcinogenesis ; 44(6): 463-475, 2023 08 18.
Article in English | MEDLINE | ID: mdl-37158456

ABSTRACT

Circular RNAs (circRNAs) have been accepted to play key roles in the development and progression of mutiple cancers including colorectal cancer (CRC). Here, we identified circ-METTL9, derived from 2 to 4 exons of METTL9 gene, may promote CRC progression by accelerating cell cycle progression. However, the role and mechanism of circ-METTL9 in CRC remains unclear. Based on our data, the expression of circ-METTL9 was significantly upregulated in CRC tissues and markedly increased in advanced tumors in CRC patients. Functional experiments demonstrated that circ-METTL9 overexpression promoted CRC cells proliferation and migration in vitro, and simultaneously enhanced CRC tumor growth and metastasis in vivo. Mechanistically, RNA immunoprecipitation (RIP) assays proved that circ-METTL9 might be a miRNA sponge, and RNA pulldown assays showed the interaction between circ-METTL9 and miR-551b-5p. Notably, cyclin-dependent kinase 6 (CDK6), a key regulator in cell cycle, is a conserved downstream target of miR-551b-5p. Taken together, our findings highlight a novel oncogenic function of circ-METTL9 in CRC progression via circ-METTL9/miR-551b-5p/CDK6 axis, which may serve as a prognostic biomarker and therapeutic target for CRC patients.


Subject(s)
Colorectal Neoplasms , MicroRNAs , Humans , Cell Line, Tumor , Cell Proliferation/genetics , Colorectal Neoplasms/pathology , Cyclin-Dependent Kinase 6/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Circular/genetics , RNA, Circular/metabolism , Methyltransferases/metabolism
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