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Finite mixture of linear regression (FMLR) models are among the most exemplary statistical tools to deal with various heterogeneous data. In this paper, we introduce a new procedure to simultaneously determine the number of components and perform variable selection for the different regressions for FMLR models via an exponential power error distribution, which includes normal distributions and Laplace distributions as special cases. Under some regularity conditions, the consistency of order selection and the consistency of variable selection are established, and the asymptotic normality for the estimators of non-zero parameters is investigated. In addition, an efficient modified expectation-maximization (EM) algorithm and a majorization-maximization (MM) algorithm are proposed to implement the proposed optimization problem. Furthermore, we use the numerical simulations to demonstrate the finite sample performance of the proposed methodology. Finally, we apply the proposed approach to analyze a baseball salary data set. Results indicate that our proposed method obtains a smaller BIC value than the existing method.
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BACKGROUND: Previous studies have validated the efficacy of both magnetic compression and surgical techniques in creating rabbit tracheoesophageal fistula (TEF) models. Magnetic compression achieves a 100% success rate but requires more time, while surgery, though less frequently successful, offers rapid model establishment and technical maturity in larger animal models. AIM: To determine the optimal approach for rabbit disease modeling and refine the process. METHODS: TEF models were created in 12 rabbits using both the modified magnetic compression technique and surgery. Comparisons of the time to model establishment, success rate, food and water intake, weight changes, activity levels, bronchoscopy findings, white blood cell counts, and biopsies were performed. In response to the failures encountered during modified magnetic compression modeling, we increased the sample size to 15 rabbit models and assessed the repeatability and stability of the models, comparing them with the original magnetic compression technique. RESULTS: The modified magnetic compression technique achieved a 66.7% success rate, whereas the success rate of the surgery technique was 33.3%. Surviving surgical rabbits might not meet subsequent experimental requirements due to TEF-related inflammation. In the modified magnetic compression group, one rabbit died, possibly due to magnet corrosion, and another died from tracheal magnet obstruction. Similar events occurred during the second round of modified magnetic compression modeling, with one rabbit possibly succumbing to aggravated lung infection. The operation time of the first round of modified magnetic compression was 3.2 ± 0.6 min, which was significantly reduced to 2.1 ± 0.4 min in the second round, compared to both the first round and that of the original technique. CONCLUSION: The modified magnetic compression technique exhibits lower stress responses, a simple procedure, a high success rate, and lower modeling costs, making it a more appropriate choice for constructing TEF models in rabbits.
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The investigation into trade-offs among plant functional traits sheds light on how plants strategically balance growth and survival when facing environmental stress. This study sought to evaluate whether trade-offs observed at both community and individual species levels could indicate adaptive fitness across an intensity of flooding intensity. The study was conducted at 25 sampling sites spanning approximately 600 km along the riparian zone in the Three Gorges Reservoir area, China. The findings revealed that, along the flooding gradient, the overall riparian community did not exhibit significant trade-offs between leaf and root traits. Examining three broadly distributed dominant species (Cynodon dactylon, Xanthium strumarium, and Abutilon theophrasti), perennial plants showed pronounced trade-offs under low flooding intensity, while annuals exhibited trade-offs under moderate and low flooding intensity. The trade-offs were evident in traits related to nitrogen-carbon resources, such as specific leaf area, root tissue density, and photosynthetic rate. However, under strong flooding intensity, the relationship between leaf and root traits of the species studied was decoupled. Furthermore, the study identified a significant correlation between soil nitrogen and the trade-off traits under moderate and low flooding intensity. Integrating results from the CSR (Competitors, Stress-tolerators, Ruderals) strategy model, species niche breath analysis, and nitrogen-regulated trade-off, the study revealed that, in the face of high flooding intensity, perennial species (C. dactylon) adopts an S-strategy, demonstrating tolerance through a conservative resource allocation that decouples leaf-root coordination. Annual species (X. strumarium and A. theophrasti), on the other hand, exhibit niche specialization along the flooding gradient, employing distinct strategies (R- and C-strategy). As flooding stress diminishes and soil nitrogen level decreases, plant strategies tend to shift towards an R-strategy with a competition for reduced N resources. In conclusion, the study highlighted the pivotal roles of soil nitrogen and flooding intensity acting as the dual determinants of species growth and tolerance. These dynamics of growth-tolerance balance were evident in the diverse trade-offs between leaf and root traits of individual plant species with different life histories, underscoring the array of adaptive strategies employed by riparian plants across the flooding intensity gradient.
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BACKGROUND: As a new technique developed in recent years, bronchoscopic intervention therapy has the advantages of minimal invasion, high safety and repeatability. The aim of this study is to investigate the clinical characteristics of bronchopleural fistula (BPF) induced by surgeries for lung malignancies or benign diseases and the effect of bronchoscopic intervention therapy for BPF, so as to provide support for prevention and treatment of BPF. METHODS: Data 64 patients with BPF who were treated by bronchoscopic intervention in Respiratory Disease Center of Dongzhimen Hospital, Beijing University of Chinese Medicine from June 2020 to September 2023 were collected. Patients with fistula diameter ≤5 mm were underwent submucous injection of macrogol, combined with blocking therapy with N-butyl cyanoacrylate, medical bioprotein glue or silicone prosthesis. Patients with fistula diameter >5 mm were implanted with different stents and cardiac occluders. Locations and characteristics of fistulas were summarized, meanwhile, data including Karnofsky performance status (KPS), shortbreath scale (SS), body temperature, pleural drainage volume and white blood cell count before and after operation were observed. RESULTS: For all 64 patients, 96 anatomic lung resections including pneumonectomy, lobectomy and segmentectomy were executed and 74 fistulas occurred in 65 fistula locations. The proportion of fistula in the right lung (63.5%) was significantly higher than that in the left (36.5%). Besides, the right inferior lobar bronchial fistula was the most common (40.5%). After operation, KPS was significantly increased, while SS, body temperature, pleural drainage volume and white blood cell count were significantly decreased compared to the preoperative values (P<0.05). By telephone follow-up or readmission during 1 month to 38 months after treament, median survival time was 21 months. 33 patients (51.6%) showed complete response, 7 patients (10.9%) showed complete clinical response, 18 patients (28.1%) showed partial response, and 6 patients (9.4%) showed no response. As a whole, the total effective rate of bronchoscopic intervention for BPF was 90.6%. CONCLUSIONS: BPF induced by pulmonary surgery can lead to severe symptoms and it is usually life-threating. Bronchoscopic intervention therapy is one of the fast and effective therapeutic methods for BPF.
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Fístula Bronquial , Neoplasias Pulmonares , Enfermedades Pleurales , Humanos , Fístula Bronquial/etiología , Fístula Bronquial/cirugía , Estudios Retrospectivos , Neoplasias Pulmonares/cirugía , Neoplasias Pulmonares/etiología , Enfermedades Pleurales/etiología , Enfermedades Pleurales/cirugía , Pleura , Neumonectomía/efectos adversosRESUMEN
Pulmonary sarcomatoid carcinoma (PSC) is a rare and highly malignant tumor, which includes the following five pathologic types: pleomorphic carcinoma, spindle cell carcinoma, giant cell carcinoma, carcinosarcoma and pulmonary blastoma. The onset of PSC is occult with non-specific clinical symptoms and signs. The clinical manifestations include irritating cough, bloody sputum, dyspnea, chest pain and so on, which are closely related to the growth and invasion site of the tumor. PSC tends to metastasize early, so most patients are already in local advanced stage or advanced stage with a median survival of 9 months at the time of hospital visit. A patient with primary PSC which led to 90% stenosis in central airway was treated by combined method of vascular and tracheoscopic intervention in our respiratory center. This treatment prolonged the patient's survival time and got a satisfactory effect at 19-month follow-up after surgery. Herein we report the case for clinical reference.â©.
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Carcinoma , Carcinosarcoma , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Pronóstico , Carcinoma/patología , Carcinosarcoma/cirugía , Carcinosarcoma/patología , Pulmón/patologíaRESUMEN
X-ray irradiation and modified atmospheres (MAs) provide eco-friendly, chemical-free methods for pest management. Although a low-oxygen atmospheric treatment improves the performance of some irradiated insects, its influence on the irradiation of quarantine insects and its impacts on pest control efficacy have yet to be investigated. Based on bioassay results, this study employed direct immersion solid-phase microextraction (DI-SPME) combined with gas chromatography-mass spectrometry (GC-MS) to determine metabolic profiles of late third-instar B. dorsalis larvae under normoxia (CON, Air), hypoxia (95% N2 + 5% O2, HY), super-hypoxia (99.5% N2 + 0.5% O2, Sup-HY), irradiation-alone (116 Gy, IR-alone), hypoxia + irradiation (HY + IR) and super-hypoxia + irradiation (Sup-HY + IR). Our findings reveal that, compared to the IR-alone group, the IR treatment under HY and Sup-HY (HY + IR and Sup-HY + IR) increases the larval pupation of B. dorsalis, and weakens the delaying effect of IR on the larval developmental stage. However, these 3 groups further hinder adult emergence under the phytosanitary IR dose of 116 Gy. Moreover, all IR-treated groups, including IR-alone, HY + IR, and Sup-HY + IR, lead to insect death as a coarctate larvae or pupae. Pathway analysis identified changed metabolic pathways across treatment groups. Specifically, changes in lipid metabolism-related pathways were observed: 3 in HY vs. CON, 2 in Sup-HY vs. CON, and 5 each in IR-alone vs. CON, HY + IR vs. CON, and Sup-HY + IR vs. CON. The treatments of IR-alone, HY + IR, and Sup-HY + IR induce comparable modifications in metabolic pathways. However, in the HY + IR, and Sup-HY + IR groups, the third-instar larvae of B. dorsalis demonstrate significantly fewer changes. Our research suggests that a low-oxygen environment (HY and Sup-HY) might enhance the radiation tolerance in B. dorsalis larvae by stabilizing lipid metabolism pathways at biologically feasible levels. Additionally, our findings indicate that the current phytosanitary IR dose contributes to the effective management of B. dorsalis, without being influenced by radioprotective effects. These results hold significant importance for understanding the biological effects of radiation on B. dorsalis and for developing IR-specific regulatory guidelines under MA environments.
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Colonization of Pseudomonas aeruginosa in the lung environments frequently leads to the enrichment of strains displaying enhanced antibiotic resistance and reduced production of quorum-sensing (QS) controlled products. However, the relationship between the emergence of QS deficient variants and antibiotic resistance remains less understood. In this study, 67 P. aeruginosa strains were isolated from the lungs of 14 patients with chronic obstructive pulmonary disease, followed by determining their genetic relationship, QS-related phenotypes and resistance to commonly used antibiotics. The integrity of P. aeruginosa QS system was checked by DNA sequencing. The relationship between the QS system and antibiotic resistance was then assessed by correlation analyses. The function of the LasR protein and bacterial virulence were evaluated through homology modeling and nematode-infection assay. The influence of antibiotic on the development of extracellular protease production ability of P. aeruginosa was tested by an evolutionary experiment. The results showed that P. aeruginosa clinical strains displayed abundant diversity in phenotype and genotype. The production of extracellular proteases was significantly negatively correlated with antibiotic resistance. The strains with enhanced antibiotic resistance also showed a notable overlap with the mutation of lasR gene, which is the core regulatory gene of P. aeruginosa QS system. Molecular docking and Caenorhabditis elegans infection assays further suggested that P. aeruginosa with impaired LasR protein could also have varying pathogenicity. Moreover, in vitro evolution experiments demonstrated that antibiotic-mediated selective pressure, particularly from Levofloxacin contributed to the emergence of extracellular protease-negative strains. Therefore, this study provides evidence for the connection of P. aeruginosa QS system and antibiotic resistance, and holds significance for developing targeted strategies to address antibiotic resistance and improving the management of antibiotic-resistant infections in chronic respiratory diseases.
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This paper presents a novel co-packaging approach through on-chip hybrid laser integration with photonic circuits using photonic wire bonding. The process involves die-bonding a low-cost semiconductor distributed-feedback (DFB) laser into a deep trench on a silicon-on-insulator (SOI) chip and coupling it to the silicon circuitry through photonic wire bonding (PWB). After characterizing the power-current-voltage (LIV) and optical spectrum of the laser, a wavelength-current relationship utilizing its tunability through self-heating a swept-frequency laser (SFL) is developed. Photonic integrated circuit (PIC) resonators are successfully characterized using the SFL method, demonstrating signal detection with a quality factor comparable to measurements conducted with an off-chip benchtop laser.
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We have clarified the study area has a history of 65 years and has been restored for 6 years. This study investigated the carbon storage characteristics of undisturbed natural forests and restored mining vegetation in Yunnan Province, China. The goal was to quantify carbon reserves and increments to inform ecological restoration strategies. Four vegetation components (tree, shrub, herb, litter) and five soil layers (0-10, 10-20, 20-30, 30-40, 40-60 cm) were analyzed. In natural forest, the tree layer stored 60% of carbon (273 Mg ha-1), overwhelmingly dominating vegetation carbon stocks. Shrub, herb, and litter layers each comprised < 1%. Surface soil layers (0-30 cm) stored 64% of soil carbon. In the restored mining area, the tree layer contributed 75% of vegetation carbon increment (16 Mg ha-1), though stocks were lower than natural forest. Soil layers showed the highest carbon increment (69%) despite lower biomass than natural conditions. Unexploited forests thus exhibit robust carbon storage, while restored mining areas have weaker carbon gains, indicating recovery potential. Strategic interventions targeting soil quality, stimulating vegetation growth, and increasing carbon sequestration could significantly augment reserves and ecological functionality. Prioritizing vegetation succession and soil revitalization are paramount to ensuring ecological integrity and sustainable development. Fostering a positive regional ecological feedback loop will be pivotal. This research quantifies carbon storage differences between undisturbed and restored mining areas, highlighting soil and vegetation as critical targets for optimizing carbon sequestration and ecosystem recovery in degraded environments.
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Carbono , Ecosistema , Carbono/metabolismo , China , Bosques , Biomasa , Árboles/metabolismo , Secuestro de Carbono , SueloRESUMEN
Fructose 1, 6-diphosphate (FDP) is an endogenous intermediate in the glycolytic pathway, as well as an allosteric activator of phosphofructokinase (PFK). Based on the role in promoting glycolysis, FDP has been widely used as a therapeutic agent for mitigating the damage of endotoxemia and ischemia/reperfusion in clinical practice. However, the effect of exogenous FDP-induced glycolysis activation on insect carbohydrate metabolism and chitin synthesis remains largely unclear. Here, we investigated for the first time the effects of FDP-Na, an allosteric activator of PFK, on the growth and development of Hyphantria cunea larvae, a serious defoliator in agriculture and forestry, especially on glycolysis and chitin synthesis. The results showed that FDP-Na significantly restrained the growth and development of H. cunea larvae and resulted in larval lethality. After treatment with FDP-Na, hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) were significantly activated, and HcHK2, HcPFK, HcPK were dramatically upregulated, which suggested that FDP-Na enhanced glycolysis in H. cunea larvae. Meanwhile, FDP-Na also distinctly impacted chitin biosynthesis by disturbing transcriptions of genes in the chitin synthesis pathway, resulting in changes of chitin contents in the midgut and epidermis of H. cunea larvae. Therefore, we considered that FDP-Na caused the growth and development arrest, and impacted chitin biosynthesis, probably by disturbing in vivo glycolysis and carbohydrate metabolism in H. cunea larvae. The findings provide a new perspective on the mechanism by which glycolysis regulates insect growth and development, and lay the foundation for exploring the potential application of glycolysis activators in pest control as well.
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Difosfatos , Mariposas Nocturnas , Animales , Larva , Glucólisis , Fosfofructoquinasas , Quitina/farmacologíaRESUMEN
Microbial polysaccharides are natural carbohydrates that can confer adhesion capacity to cells and protect them from harsh environments. Due to their various physiological activities, these macromolecules are widely used in food, medicine, environmental, cosmetic, and textile applications. Microbial co-culture is an important strategy that is used to increase the production of microbial polysaccharides or produce new polysaccharides (structural alterations). This is achieved by exploiting the symbiotic/antagonistic/chemo-sensitive interactions between microbes and stimulating the expression of relevant silent genes. In this article, we review the performance of polysaccharides produced using microbial co-culture in terms of yield, antioxidant activity, and antibacterial, antitumor, and anti-inflammatory properties, in addition to the advantages and application prospects of co-culture. Moreover, the potential for microbial polysaccharides to be used in various applications is discussed.
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BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic fatal disease of unknown etiology. Its pathological manifestations include excessive proliferation and activation of fibroblasts and deposition of extracellular matrix. Endothelial cell-mesenchymal transformation (EndMT), a novel mechanism that generates fibroblast during IPF, is responsible for fibroblast-like phenotypic changes and activation of fibroblasts into hypersecretory cells. However, the exact mechanism behind EndMT-derived fibroblasts and activation is uncertain. Here, we investigated the role of sphingosine 1-phosphate receptor 1 (S1PR1) in EndMT-driven pulmonary fibrosis. METHODS: We treated C57BL/6 mice with bleomycin (BLM) in vivo and pulmonary microvascular endothelial cells with TGF-ß1 in vitro. Western blot, flow cytometry, and immunofluorescence were used to detect the expression of S1PR1 in endothelial cells. To evaluate the effect of S1PR1 on EndMT and endothelial barrier and its role in lung fibrosis and related signaling pathways, S1PR1 agonist and antagonist were used in vitro and in vivo. RESULTS: Endothelial S1PR1 protein expression was downregulated in both in vitro and in vivo models of pulmonary fibrosis induced by TGF-ß1 and BLM, respectively. Downregulation of S1PR1 resulted in EndMT, indicated by decreased expression of endothelial markers CD31 and VE-cadherin, increased expression of mesenchymal markers α-SMA and nuclear transcription factor Snail, and disruption of the endothelial barrier. Further mechanistic studies found that stimulation of S1PR1 inhibited TGF-ß1-mediated activation of the Smad2/3 and RhoA/ROCK1 pathways. Moreover, stimulation of S1PR1 attenuated Smad2/3 and RhoA/ROCK1 pathway-mediated damage to endothelial barrier function. CONCLUSIONS: Endothelial S1PR1 provides protection against pulmonary fibrosis by inhibiting EndMT and attenuating endothelial barrier damage. Accordingly, S1PR1 may be a potential therapeutic target in progressive IPF.
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Fibrosis Pulmonar Idiopática , Fibrosis Pulmonar , Ratones , Animales , Fibrosis Pulmonar/patología , Factor de Crecimiento Transformador beta1/metabolismo , Células Endoteliales/metabolismo , Receptores de Esfingosina-1-Fosfato/metabolismo , Receptores de Esfingosina-1-Fosfato/uso terapéutico , Ratones Endogámicos C57BL , Bleomicina/farmacología , Transición Epitelial-Mesenquimal , Fibroblastos/metabolismo , Fibrosis Pulmonar Idiopática/patologíaRESUMEN
Polypeptoids are a family of synthetic peptidomimetic polymers featuring N-substituted polyglycine backbones with large chemical and structural diversity. Their synthetic accessibility, tunable property/functionality, and biological relevance make polypeptoids a promising platform for molecular biomimicry and various biotechnological applications. To gain insight into the relationship between the chemical structure, self-assembly behavior, and physicochemical properties of polypeptoids, many efforts have been made using thermal analysis, microscopy, scattering, and spectroscopic techniques. In this review, we summarize recent experimental investigations that have focused on the hierarchical self-assembly and phase behavior of polypeptoids in bulk, thin film, and solution states, highlighting the use of advanced characterization tools such as in situ microscopy and scattering techniques. These methods enable researchers to unravel multiscale structural features and assembly processes of polypeptoids over a wide range of length and time scales, thereby providing new insights into the structure-property relationship of these protein-mimetic materials.
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Nano-/microplastics accumulate in aquatic bodies and raise increasing threats to ecosystems and human health. The limitation of existing water cleanup strategies, especially in the context of nano-/microplastics, primarily arises from their complexity (morphological, compositional, and dimensional). Here, highly efficient and bio-based flowthrough capturing materials (bioCap) are reported to remove a broad spectrum of nano-/microplastics from water: polyethylene terephthalate (anionic, irregular shape), polyethylene (net neutral, irregular shape), polystyrene (anionic and cationic, spherical shape), and other anionic and spherical shaped particles (polymethyl methacrylate, polypropylene, and polyvinyl chloride). Highly efficient bioCap systems that adsorb the ubiquitous particles released from beverage bags are demonstrated. As evidence of removal from drinking water, the in vivo biodistribution of nano-/microplastics is profiled, confirming a significant reduction of particle accumulation in main organs. The unique advantage of phenolic-mediated multi-molecular interactions is employed in sustainable, cost-effective, and facile strategies based on wood sawdust support for the removal of challenging nano-/microplastics pollutions.
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Microplásticos , Contaminantes Químicos del Agua , Humanos , Plásticos , Polifenoles , Ecosistema , Madera/química , Distribución Tisular , Monitoreo del Ambiente , AguaRESUMEN
Polymer nanoparticles generally refer to hydrophobic polymers-based nanoparticles, which have been extensively studied in the nanomedicine field due to their good biocompatibility, efficient long-circulation characteristics, and superior metabolic discharge patterns over other nanoparticles. Existing studies have proved that polymer nanoparticles possess unique advantages in the diagnosis and treatment of cardiovascular diseases, and have been transformed from basic researches to clinical applications, especially in the diagnosis and treatment of atherosclerosis (AS). However, the inflammatory reaction induced by polymer nanoparticles would induce the formation of foam cells and autophagy of macrophages. In addition, the variations in the mechanical microenvironment of cardiovascular diseases may cause the enrichment of polymer nanoparticles. These could possibly promote the occurrence and development of AS. Herein, this review summarized the recent application of polymer nanoparticles in the diagnosis and treatment of AS, as well as the relationship between polymer nanoparticles and AS and the associated mechanism, with the aim to facilitate the development of novel nanodrugs for the treatment of AS.
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Aterosclerosis , Enfermedades Cardiovasculares , Nanopartículas , Humanos , Polímeros/química , Nanopartículas/química , Sistemas de Liberación de Medicamentos , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/diagnóstico , Aterosclerosis/patologíaRESUMEN
Porphyromonas gingivalis is a keystone pathogen in periodontitis. Our previous study indicated that periodontitis induced by P. gingivalis increased the percentage of CD19+ B cells but decreased the ratio of IL-10-producing regulatory B cells (B10) in collagen-induced arthritis (CIA) mice. It is still unclear which virulence factors of P. gingivalis are involved in these processes. Here, we compared the effects of different components of P. gingivalis on the biogenesis of B10 cells and found that the decreased proportion of B10 cells mainly resulted from the undenatured proteins other than the DNA, RNA, or lipopolysaccharides of P. gingivalis. As gingipains are enzymes and virulence factors that play a vital role in the progression in periodontitis through affecting the innate and adaptive immune system, we then compared the influence of the wild-type (WT) strain of P. gingivalis (ATCC 33277) and its isogenic gingipain-null mutant (∆K∆RAB) on the differentiation of splenic B cells into B10 cells. Interestingly, compared to WT strain, ∆K∆RAB treatment increased the frequency of B10 cells as well as the expression of IL-6 in B cells. Furthermore, the acute peritonitis, an ideal model for the quick evaluation of immune effects of agents, induced by ∆K∆RAB, showed the higher IL-6 production and proportion of B10 cells compared with WT. Finally, we performed transcriptomic analysis to better understand the effects and possible mechanisms of gingipains on B cells. Compared with WT, ∆K∆RAB upregulated the PI3K-Akt pathway of B cells, which is important for IL-10 production and B10 cell biogenesis, and more activated Jak-STAT pathway, which is a classical signaling pathway mediated by IL-6. Cumulatively, this study preliminarily revealed that gingipains of P. gingivalis are vital virulence factors downregulating B10 cells and altering immune responses.
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Periodontitis , Porphyromonas gingivalis , Animales , Ratones , Cisteína-Endopeptidasas Gingipaínas/metabolismo , Factores de Virulencia/metabolismo , Interleucina-10/metabolismo , Interleucina-6 , Fosfatidilinositol 3-Quinasas/metabolismo , Quinasas Janus/metabolismo , Adhesinas Bacterianas/genética , Adhesinas Bacterianas/metabolismo , Transducción de Señal , Factores de Transcripción STAT/metabolismoRESUMEN
Much of biological electron transfer occurs between proteins. These molecular processes usually involve molecular recognition and intermolecular electron transfer (inter-ET). The inter-ET reaction between copper-containing nitrite reductase (CuNiR) and partner protein pseudoazurin (PAz) is the first step in denitrification, which is affected by intermolecular association. However, the transient interaction between CuNiR and PAz and the indistinct inter-ET pathway pose challenges for people to understand the biological functions of the CuNiR-PAz complex. Thus, molecular dynamics simulation and quantum mechanical calculation were used to investigate the question in this study. The interaction of the interface residues was determined through hydrogen bonds, root-mean-square deviation, root-mean-square fluctuation, the dynamics cross-correlation matrix, and molecular mechanics Poisson-Boltzmann surface area of molecular dynamics simulations. The interactions among the residues Glu89, Gly200, Asp205, Asn91, Glu204, Thr92, and Met141 on CuNiR and the residues Lys109, Ala15, Lys10, Asn9, Ile110, Met84, and Met16 on PAz are responsible for the stabilization of the complex. The binding free energy is up to -25.33 kcal mol-1. We compared the wild-type and mutant (M84A) interfacial optimized complex models at the CAM-B3LYP level with Grimme dispersion corrections (GD3) to confirm Met84 as a relay station for promoting the inter-ET. Additionally, to test whether Met84 may combine with the adjacent Met141 to form a special two-center, three-electron (Sâ´S)+ structure to promote the inter-ET, QM/MM was further performed to discuss the possibility of generating an electron stepping stone. Our study will promote a deep understanding of the stable protein-protein interaction, and the identified inter-residue interaction will be theoretical guidance for enhancing the catalytic activity of CuNiR in denitrification.
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Cobre , Simulación de Dinámica Molecular , Humanos , Cobre/química , Electrones , Oxidación-Reducción , Nitrito Reductasas/químicaRESUMEN
We report the whole-genome sequence of the endophytic Actinacidiphila bryophytorum strain DS3, which was isolated from the roots of the medicinal plant Dysosma versipellis. The DS3 strain genome consists of a chromosome of 8,265,668 bp, with a GC content of 72.47%, including 7,121 coding sequences.
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Bistortae Rhizoma (Quanshen), a dried rhizome of Polygonum bistorta L., is edited in Chinese Pharmacopiea as only one of species of Polygonum. There are many adulterants were used as Quanshen such as "Eryeliao," "Taipingyangliao" and "Daogenliao" because of its remarkable functions. Previous researches had shown that there were not significant differences among them. Therefore, it is necessary to conduct a comprehensive authentication of these herbs samples. Analyses of the microscopic features of the powders and transverse sections of herbs are the most significant measures of accreditation of the quality of traditional Chinese medicine. In this study, microscopic observation of powders of the herbs and cross-sectional tissues were performed by using common light microscopy, polarized light microscopy and combining PCA analysis to identify Quanshen and three adulterants. We found that calcium oxalate clusters can be a good microscopic marker index to distinguish Quabshen and Eryeliao. In addition, Quanshen and the other two can be further distinguished by the characteristics of cork layer cells and vascular bundles on transverse section of the rhizome. Our results showed that the approach, microscopic features and digital characterization, is efficient, convenient, and reliable.
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Medicamentos Herbarios Chinos , Rizoma , Rizoma/anatomía & histología , Estudios Transversales , Medicina Tradicional China , Microscopía de PolarizaciónRESUMEN
The steroid hormone 20-hydroxyecdysone (20E) has been described to regulate fat body lipid metabolism in insects, but its accurate regulatory mechanism, especially the crosstalk between 20E-induced lipid metabolism and gluconeogenesis remains largely unclear. Here, we specially investigated the effect of 20E on lipid metabolism and gluconeogenesis in the fat body of Hyphantria cunea larvae, a notorious pest in forestry. Lipidomics analysis showed that a total of 1 907 lipid species were identified in the fat body of H. cunea larvae assigned to 6 groups and 48 lipid classes. The differentially abundant lipids analysis showed a significant difference between 20E-treated and control samples, indicating that 20E caused a remarkable alteration of lipidomics profiles in the fat body of H. cunea larvae. Further studies demonstrated that 20E accelerated fatty acid ß-oxidation, inhibited lipid synthesis, and promoted lipolysis. Meanwhile, the activities of pyruvate carboxylase, phosphoenolpyruvate carboxykinase, fructose-1,6-bisphosphatase, and glucose-6-phosphatase were dramatically suppressed by 20E in the fat body of H. cunea larvae. As well, the transcriptions of genes encoding these 4 rate-limiting gluconeogenic enzymes were significantly downregulated in the fat body of H. cunea larvae after treatment with 20E. Taken together, our results revealed that 20E disturbed fat body lipid homeostasis, accelerated fatty acid ß-oxidation and promoted lipolysis, but negatively regulated gluconeogenesis in H. cunea larvae. The findings might provide a new insight into hormonal regulation of glucose and lipid metabolism in insect fat body.