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1.
Altern Ther Health Med ; 30(1): 386-390, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37793338

RESUMO

Background: Acute gastroenteritis is a frequently encountered diarrheal illness in children, often self-limiting but occasionally linked to substantial mortality and morbidity, demanding effective approaches for assessment and intervention. While the utilization of the Pediatric Early Warning Score (PEWS) and the Situation-Background-Assessment-Recommendation system (SBAR) in pediatric patient management is recognized as effective, research in this area remains limited. Objective: Our study aimed to investigate the potential impact of PEWS and SBAR systems on the outcomes of pediatric patients with acute gastroenteritis. Methods: We conducted a randomized controlled trial at our hospital, enrolling 124 children aged 3 to 12 years diagnosed with acute gastroenteritis. These participants were randomly assigned to either a control group (62 cases) or an intervention group (62 cases). Different outcomes were assessed, including the frequency and duration of diarrhea and vomiting, the Modified Vesikari Scale (MVS), the Clinical Dehydration Scale (CDS), and follow-up physician visits. We utilized a two-group independent sample t test to compare outcomes between the two groups. Results: Our study resulted in statistically significant findings favoring the intervention group regarding the frequency and duration of diarrhea and vomiting, the MVS, the CDS, and the need for repeat healthcare visits. Conclusions: The integration of PEWS with SBAR appears to offer improved outcomes for children afflicted with acute gastroenteritis.


Assuntos
Escore de Alerta Precoce , Gastroenterite , Criança , Humanos , Diarreia/diagnóstico , Diarreia/terapia , Gastroenterite/diagnóstico , Gastroenterite/terapia , Vômito/terapia , Pré-Escolar
2.
Int J Mol Sci ; 24(13)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37445626

RESUMO

Metabolites play critical roles in macrophage polarization and in their function in response to infection and inflammation. α-aminobutyric acid (AABA), a non-proteinogenic amino acid which can be generated from methionine, threonine, serine, and glycine, has not been studied extensively in relation to macrophage polarization and function. In this study, we aimed to investigate the immunomodulatory function of AABA in regulating M1 macrophage polarization and function in vitro and in vivo. We stimulated bone-marrow-derived macrophages with lipopolysaccharide (LPS) to generate M1 macrophages. Subsequently, we induced sepsis and colitis in mice, followed by treatment with AABA. We then analyzed the samples using ELISA, real-time PCR, Western blotting, flow cytometry, and histopathological analysis to evaluate cytokine secretion, inflammatory gene expression, macrophage activation, disease progression, and inflammation severity. Additionally, metabolomic and chromatin immunoprecipitation-qPCR were conducted to investigate the function of AABA on metabolic reprogramming and epigenetic modifications of M1 macrophages. Our results revealed that AABA inhibited M1 macrophage polarization and function, which led to prolonged survival in septic mice and reduced disease severity in colitis mice. Mechanically, AABA promoted oxidative phosphorylation (OXPHOS) and glutamine and arginine metabolism while inhibiting glycolysis. Moreover, AABA could increase the occupancy of trimethylation of histone H3K27 at the promoter regions of M1 macrophage-associated inflammatory genes, which contributed to the inhibition of M1 macrophage polarization. These findings suggest that AABA may have therapeutic potential for inflammatory diseases by regulating macrophage polarization and function through metabolic and epigenetic pathways.


Assuntos
Colite , Macrófagos , Camundongos , Animais , Macrófagos/metabolismo , Inflamação/metabolismo , Colite/genética , Colite/metabolismo , Epigênese Genética , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos
3.
Front Immunol ; 13: 942465, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36045674

RESUMO

Follicular helper T (TFH) cells provide specialized help for B cells to ensure optimal humoral immunity. The histone methyltransferase EZH2, as a chromatin repressor, secures the TFH differentiation by promoting TFH lineage associated gene expression during acute viral infection, including Tcf7 and Bcl6. By using conditional deletion murine system, we observed that EZH2 ablation in CD4+ T cells was accompanied by aberrant accumulation of DNA methyltransferases (DNMTs) DNMT1 and DNMT3B in TFH cells. And the loss of EZH2 promoted aggravation of DNA methylation status at Tcf7 locus. Therefore, our findings suggested that EZH2 plays an important role in maintenance of hypomethylation at Tcf7 locus thus affecting TFH differentiation during acute viral infection.


Assuntos
Metilação de DNA , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Fator 1-alfa Nuclear de Hepatócito/genética , Linfócitos T Auxiliares-Indutores , Viroses , Animais , Diferenciação Celular , Histona Metiltransferases/metabolismo , Camundongos , Viroses/imunologia
4.
Appl Environ Microbiol ; 88(7): e0252921, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35323023

RESUMO

As a key bacterial second messenger, cyclic di-GMP (c-di-GMP) regulates various physiological processes, such as motility, biofilm formation, and virulence. Cellular c-di-GMP levels are regulated by the opposing activities of diguanylate cyclases (DGCs) and phosphodiesterases (PDEs). Beyond that, the enzymatic activities of c-di-GMP metabolizing proteins are controlled by a variety of extracellular signals and intracellular physiological conditions. Here, we report that pdcA (BTH_II2363), pdcB (BTH_II2364), and pdcC (BTH_II2365) are cotranscribed in the same operon and are involved in a regulatory cascade controlling the cellular level of c-di-GMP in Burkholderia thailandensis. The GGDEF domain-containing protein PdcA was found to be a DGC that modulates biofilm formation, motility, and virulence in B. thailandensis. Moreover, the DGC activity of PdcA was inhibited by phosphorylated PdcC, a single-domain response regulator composed of only the phosphoryl-accepting REC domain. The phosphatase PdcB affects the function of PdcA by dephosphorylating PdcC. The observation that homologous operons of pdcABC are widespread among betaproteobacteria and gammaproteobacteria suggests a general mechanism by which the intracellular concentration of c-di-GMP is modulated to coordinate bacterial behavior and virulence. IMPORTANCE The transition from planktonic cells to biofilm cells is a successful strategy adopted by bacteria to survive in diverse environments, while the second messenger c-di-GMP plays an important role in this process. Cellular c-di-GMP levels are mainly controlled by modulating the activity of c-di-GMP-metabolizing proteins via the sensory domains adjacent to their enzymatic domains. However, in most cases how c-di-GMP-metabolizing enzymes are modulated by their sensory domains remains unclear. Here, we reveal a new c-di-GMP signaling cascade that regulates motility, biofilm formation, and virulence in B. thailandensis. While pdcA, pdcB, and pdcC constitute an operon, the phosphorylated PdcC binds the PAS sensory domain of PdcA to inhibit its DGC activity, with PdcB dephosphorylating PdcC to derepress the activity of PdcA. We also show this c-di-GMP regulatory model is widespread in the phylum Proteobacteria. Our study expands the current knowledge of how bacteria regulate intracellular c-di-GMP levels.


Assuntos
Proteínas de Escherichia coli , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , Burkholderia , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Proteínas de Escherichia coli/genética , Diester Fosfórico Hidrolases/metabolismo , Fósforo-Oxigênio Liases/genética , Fósforo-Oxigênio Liases/metabolismo , Virulência
5.
Molecules ; 27(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35011549

RESUMO

Angelica sinensis, a perennial herb that produces ferulic acid and phthalides for the treatment of cardio-cerebrovascular diseases, prefers growing at an altitude of 1800-3000 m. Geographical models have predicted that high altitude, cool temperature and sunshade play determining roles in geo-authentic formation. Although the roles of altitude and light in yield and quality have been investigated, the role of temperature in regulating growth, metabolites biosynthesis and gene expression is still unclear. In this study, growth characteristics, metabolites contents and related genes expression were investigated by exposing A. sinensis to cooler (15 °C) and normal temperatures (22 °C). The results showed that plant biomass, the contents of ferulic acid and flavonoids and the expression levels of genes related to the biosynthesis of ferulic acid (PAL1, 4CLL4, 4CLL9, C3H, HCT, CCOAMT and CCR) and flavonoids (CHS and CHI) were enhanced at 15 °C compared to 22 °C. The contents of ligustilide and volatile oils exhibited slight increases, while polysaccharide contents decreased in response to cooler temperature. Based on gene expression levels, ferulic acid biosynthesis probably depends on the CCOAMT pathway and not the COMT pathway. It can be concluded that cool temperature enhances plant growth, ferulic acid and flavonoid accumulation but inhibits polysaccharide biosynthesis in A. sinensis. These findings authenticate that cool temperature plays a determining role in the formation of geo-authentic and also provide a strong foundation for regulating metabolites production of A. sinensis.


Assuntos
Angelica sinensis/fisiologia , Temperatura Baixa , Ácidos Cumáricos/metabolismo , Flavonoides/biossíntese , Polissacarídeos/biossíntese , 4-Butirolactona/análogos & derivados , Metabolismo dos Carboidratos , Regulação da Expressão Gênica de Plantas , Óleos Voláteis , Óleos de Plantas , Fenômenos Fisiológicos Vegetais
6.
Environ Sci Pollut Res Int ; 29(5): 6990-7000, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34467488

RESUMO

Though gold mines provide significant economic benefits to local governments, mining causes soil pollution by potentially toxic trace elements (PTEs) in mining areas, especially in the Qinghai-Tibet Plateau. Screening of native plant species from mining areas is now an effective, inexpensive, and eco-friendly method for the remediation of PTEs in situ. In the present study, we conducted experiments to assess the accumulation of As, Cd, Pb, and Zn in 12 native plant species growing on a typical gold mining area in the Qinghai-Tibet Plateau. Our results showed that rhizosphere soils have high soil organic matter content, high levels of As, and moderate levels of Cd. Geranium pylzowianum accumulated relatively higher As in its shoots and exhibited translocation factor (TF) higher than 1 for As (4.65), Cd (1.87), and Pb (1.36). Potentilla saundersiana had bioconcentration factor of shoot (BCF-S) higher than 1 for Cd (4.52) and Pb (1.70), whereas its TF was higher than 1 for As, Cd, Pb, and Zn. These plant species exhibit strong tolerance to these PTEs. Furthermore, Elymus nutans accumulated low levels of As, Cd, Pb, and Zn in their shoots and exhibited TF values lower than 1 for the four PTEs. Therefore, G. pylzowianum is a promising candidate for the in situ phytoextraction of As, and P. saundersiana can be used as an effective plant for Cd and Pb phytoextraction. E. nutans is better suited for the phytostabilisation of multiple PTEs. This work is of significant importance for screening native plant species that can provide a reference for phytoremediation of PTE-contaminated soils in this area or other place with similar climate, and has a good potential for developing PTE phytoremediation strategies at mining sites.


Assuntos
Metais Pesados , Poluentes do Solo , Oligoelementos , Biodegradação Ambiental , Ouro , Metais Pesados/análise , Mineração , Solo , Poluentes do Solo/análise , Tibet , Oligoelementos/análise
7.
J Leukoc Biol ; 110(6): 1057-1067, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34612525

RESUMO

Iron plays a critical role in immune responses. However, its role in T helper cell differentiation and function remains poorly understood. In this study, it is shown that the restraint of iron availability through blocking CD71-mediated iron endocytosis impaired the differentiation and pathogenicity of TH 17 cells. Administrations of anti-CD71 mAb could relieve the development of experimental autoimmune encephalomyelitis (EAE). Mechanistically, the iron deficiency due to the blocking of CD71 enhanced IL-2 expression, which further restrained the differentiation of TH 17 cells. Meanwhile, CD71 blockade impaired histone modifications of Il17 gene and reduced the recruitment of RORγt to Il17a locus. In sum, the findings reveal that iron plays a pivotal role in regulating TH 17 cell differentiation and function in autoimmune diseases.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Ferro/imunologia , Ferro/metabolismo , Células Th17/imunologia , Animais , Antígenos CD/imunologia , Antígenos CD/metabolismo , Diferenciação Celular/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Receptores da Transferrina/imunologia , Receptores da Transferrina/metabolismo , Células Th17/metabolismo
8.
Nat Commun ; 11(1): 5371, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097715

RESUMO

Autoinducer-2 (AI-2) is a quorum sensing signal that mediates communication within and between many bacterial species. However, its known receptors (LuxP and LsrB families) are not found in all the bacteria capable of responding to this signaling molecule. Here, we identify a third type of AI-2 receptor, consisting of a dCACHE domain. AI-2 binds to the dCACHE domain of chemoreceptors PctA and TlpQ of Pseudomonas aeruginosa, thus inducing chemotaxis and biofilm formation. Boron-free AI-2 is the preferred ligand for PctA and TlpQ. AI-2 also binds to the dCACHE domains of histidine kinase KinD from Bacillus subtilis and diguanylate cyclase rpHK1S-Z16 from Rhodopseudomonas palustris, enhancing their enzymatic activities. dCACHE domains (especially those belonging to a subfamily that includes the AI-2 receptors identified in the present work) are present in a large number of bacterial and archaeal proteins. Our results support the idea that AI-2 serves as a widely used signaling molecule in the coordination of cell behavior among prokaryotic species.


Assuntos
Quimiotaxia/fisiologia , Homosserina/análogos & derivados , Homosserina/metabolismo , Lactonas/metabolismo , Células Procarióticas/metabolismo , Proteínas Arqueais , Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Liases de Carbono-Enxofre/genética , Liases de Carbono-Enxofre/metabolismo , Proteínas de Transporte/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli , Homosserina/química , Homosserina/genética , Lactonas/química , Ligantes , Fósforo-Oxigênio Liases , Pseudomonas aeruginosa/metabolismo , Percepção de Quorum , Rodopseudomonas/metabolismo , Transdução de Sinais/fisiologia
9.
J Cancer Res Ther ; 14(Supplement): S1035-S1040, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30539842

RESUMO

AIM: Norcantharidin (NCTD) has been used as a clinical antineoplastic drug in China for several years, and diamminedichloroplatinum is a valuable clinical cancer chemotherapy agent. Here, we tried to investigate the effects of NCTD plus diamminedichloroplatinum on hepatic carcinoma in murine. MATERIALS AND METHODS: In vivo and in vitro investigations on anticancer effects of the two drugs were individually made. RESULT: In vitro, the combination of the two drugs resulted in apparent apoptosis and cell proliferation inhibitions of H22 cancer cells. Meanwhile, their coadministration in vivo produced significant suppressions of tumor growth and cancerometastasis. Further, CD31 immunohistochemistry and matrigel tube formation assay demonstrated that angiogenesis was inhibited by NCTD plus diamminedichloroplatinum in vivo and in vitro, respectively. CONCLUSION: Based on the findings, we concluded that NCTD plus diamminedichloroplatinum may have an additive anticancer efficacy because the two drugs work in different ways, and thus, their combination had inhibited cancer cell proliferations and tumor angiogenesis more effectively than either of the compounds alone.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Cisplatino/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Carcinoma Hepatocelular/secundário , Linhagem Celular Tumoral/transplante , Proliferação de Células/efeitos dos fármacos , Cisplatino/uso terapêutico , Modelos Animais de Doenças , Sinergismo Farmacológico , Feminino , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Resultado do Tratamento
10.
Cancer Biother Radiopharm ; 33(1): 25-31, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29466034

RESUMO

Cancer vaccines mostly aim to induce cytotoxic T lymphocytes (CTLs) against tumors. An appropriate adjuvant is of fundamental importance for inducing cellular immune response. Since the antigen in particulate form is substantially more immunogenic than soluble form antigen, it is beneficial to interact with antigen-presenting cells membrane to induce robust CD8+ T cell activation following vaccination. Based on previous research, we designed an adjuvant formulation by combining Astragalus saponins, cholesterol, and liposome to incorporate antigen into a particulate delivery system, so as to enhance cellular immune response. Meanwhile, angiogenesis contributes to tumor growth and metastasis, and basic fibroblast growth factor (bFGF) is involved in tumor angiogenesis. Therefore, using lipo-saponins adjuvant formulation and a human recombinant bFGF antigen protein, we tried to induce bFGF-specific CTL response to inhibit tumor angiogenesis to achieve antitumor activity. After five immunizations, the lipo-saponins/bFGF complex elicited robust antibody response and markedly higher amount of interferon-γ in BALB/c mice, resulting in superior antitumor activities. Decreased microvessel density in CD31 immunohistochemistry and the lysis of vascular endothelial cells by the T lymphocytes from the immunized mice indicated that the immunity inhibited the angiogenesis of tumors and further led to the inhibition of tumors. Our data suggest that the approach to construct adjuvant formulation between liposome and Astragalus saponins appeared highly desirable, and that Astragalus saponins may be utilized as a valuable additive for enhancing the effectiveness of vaccines and stimulating an appropriate immune response that can benefit tumor therapy.


Assuntos
Adjuvantes Imunológicos/química , Vacinas Anticâncer/química , Lipossomos/química , Saponinas/química , Saponinas/imunologia , Sequência de Aminoácidos , Animais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C
11.
Cancer Biol Ther ; 19(6): 518-524, 2018 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-29405828

RESUMO

Tumor growth and metastasis are closely related to angiogenesis. Basic fibroblast growth factor(bFGF) is an angiogenic factor, and up-regulated expression of bFGF plays a crucial role in the development and metastasis of melanoma. Therefore, in this study, we sought to achieve antitumor activity by immunity targeting bFGF which would inhibit tumor angiogenesis and simultaneously induce bFGF specific cytotoxic T lymphocytes to kill melanoma cells. A human bFGF protein was used as exogenous antigen, coupled with a saponin-liposome adjuvant formulation to enhance CTL response. The results showed that the immunity induced strong immune response and produced prominent anti-cancer activities. CD31 immunohistochemistry and alginate-encapsulated tumor cell assay displayed that tumor angiogenesis was effectively inhibited. Further, the higher production of IFN-γ and cytotoxic T lymphocyte killing assay suggested that the anti-cancer activities may mainly depend on cellular immune response, which could cause the inhibition of tumor angiogenesis and specific killing of tumor cells by bFGF-specific cytotoxic T lymphocytes. We concluded that immunotherapy targeting bFGF may be a prominent strategy for melanoma, and that the adjuvant formulation of saponin-liposome is very desirable in enhancing cytotoxic T lymphocytes response.


Assuntos
Vacinas Anticâncer/uso terapêutico , Fator 2 de Crescimento de Fibroblastos/imunologia , Imunoterapia/métodos , Melanoma/tratamento farmacológico , Animais , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/farmacologia , Modelos Animais de Doenças , Feminino , Humanos , Melanoma/patologia , Camundongos
12.
IEEE Trans Syst Man Cybern B Cybern ; 38(4): 1008-13, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18632392

RESUMO

This paper applies a neural-network-based approximate dynamic programming method, namely, the direct heuristic dynamic programming (direct HDP), to a large power system stability control problem. The direct HDP is a learning- and approximation-based approach to addressing nonlinear coordinated control under uncertainty. One of the major design parameters, the controller learning objective function, is formulated to directly account for network-wide low-frequency oscillation with the presence of nonlinearity, uncertainty, and coupling effect among system components. Results include a novel learning control structure based on the direct HDP with applications to two power system problems. The first case involves static var compensator supplementary damping control, which is used to provide a comprehensive evaluation of the learning control performance. The second case aims at addressing a difficult complex system challenge by providing a new solution to a large interconnected power network oscillation damping control problem that frequently occurs in the China Southern Power Grid.


Assuntos
Algoritmos , Modelos Teóricos , Oscilometria/métodos , Centrais Elétricas , Programação Linear , Teoria de Sistemas , Simulação por Computador , Retroalimentação
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