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1.
BMC Infect Dis ; 21(1): 620, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34187390

RESUMO

BACKGROUND: Candida pelliculosa is an ecological fungal species that can cause infections in immunocompromised individuals. Numerous studies globally have shown that C. pelliculosa infects neonates. An outbreak recently occurred in our neonatal intensive care unit; therefore, we aimed to evaluate the risk factors in this hospital-acquired fungal infection. METHODS: We performed a case-control study, analysing the potential risk factors for neonatal infections of C. pelliculosa so that infection prevention and control could be implemented in our units. Isolated strains were tested for drug resistance and biofilm formation, important factors for fungal transmission that give rise to hospital-acquired infections. RESULTS: The use of three or more broad-spectrum antimicrobials or long hospital stays were associated with higher likelihoods of infection with C. pelliculosa. The fungus was not identified on the hands of healthcare workers or in the environment. All fungal isolates were susceptible to anti-fungal medications, and after anti-fungal treatment, all infected patients recovered. Strict infection prevention and control procedures efficiently suppressed infection transmission. Intact adhesin-encoding genes, shown by genome analysis, indicated possible routes for fungal transmission. CONCLUSIONS: The use of three or more broad-spectrum antimicrobials or a lengthy hospital stay is theoretically associated with the risk of infection with C. pelliculosa. Strains that we isolated are susceptible to anti-fungal medications, and these were eliminated by treating all patients with an antifungal. Transmission is likely via adhesion to the cell surface and biofilm formation.


Assuntos
Biofilmes , Candidíase/epidemiologia , Candidíase/prevenção & controle , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Surtos de Doenças/prevenção & controle , Equipamentos e Provisões/microbiologia , Unidades de Terapia Intensiva Neonatal , Saccharomycetales/genética , Antifúngicos/uso terapêutico , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Estudos de Casos e Controles , China/epidemiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Feminino , Pessoal de Saúde , Humanos , Recém-Nascido , Controle de Infecções/métodos , Tempo de Internação , Masculino , Testes de Sensibilidade Microbiana , RNA Fúngico/genética , Fatores de Risco , Saccharomycetales/isolamento & purificação
2.
BMC Cancer ; 17(1): 719, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29115924

RESUMO

BACKGROUND: Epithelial-mesenchymal transition (EMT) is an early event in tumour invasion and metastasis, and widespread and distant metastasis at early stages is the typical biological behaviour in small cell lung cancer (SCLC). Our previous reports showed that high expression of the transcription factor E2F1 was involved in the invasion and metastasis of SCLC, but the role of E2F1 in the process of EMT in SCLC is unknown. METHODS: Immunohistochemistry was performed to evaluate the expressions of EMT related markers. Immunofluorescence was used to detect the expressions of cytoskeletal proteins and EMT related markers when E2F1 was silenced in SCLC cell lines. Adenovirus containing shRNA against E2F1 was used to knock down the E2F1 expression, and the dual luciferase reporter system was employed to clarify the regulatory relationship between E2F1 and ZEB2. RESULTS: In this study, we observed the remodelling of cytoskeletal proteins when E2F1 was silenced in SCLC cell lines, indicating that E2F1 was involved in the EMT in SCLC. Depletion of E2F1 promoted the expression of epithelial markers (CDH1 and CTNNB1) and inhibited the expression of mesenchymal markers (VIM and CDH2) in SCLC cell lines, verifying that E2F1 promotes EMT occurrence. Next, the mechanism by which E2F1 promoted EMT was explored. Among the CDH1 related inhibitory transcriptional regulators ZEB1, ZEB2, SNAI1 and SNAI2, the expression of ZEB2 was the highest in SCLC tissue samples and was highly consistent with E2F1 expression. ChIP-seq data and dual luciferase reporter system analysis confirmed that E2F1 could regulate ZEB2 gene expression. CONCLUSION: Our data supports that E2F1 promotes EMT by regulating ZEB2 gene expression in SCLC.


Assuntos
Fator de Transcrição E2F1/metabolismo , Transição Epitelial-Mesenquimal , Neoplasias Pulmonares/metabolismo , Carcinoma de Pequenas Células do Pulmão/metabolismo , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Masculino , Regiões Promotoras Genéticas , Carcinoma de Pequenas Células do Pulmão/genética , Regulação para Cima , Homeobox 2 de Ligação a E-box com Dedos de Zinco/metabolismo
3.
Plant Divers ; 46(2): 247-255, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38807903

RESUMO

When benefiting other beneficiaries, cushion plants may reciprocally receive feedback effects. The feedback effects on different sex morphs, however, remains unclear. In this study, taking the gynodioecious Arenaria polytrichiodes as a model species, we aimed to assess the sex-specific facilitation intensity of cushion plant by measuring the beneficiary cover ratio, and to assess the potential costs in cushion reproductive functions by measuring the flower and fruit cover ratios. The total beneficiary cover ratio was similar between females and hermaphrodites. Females produced much less flowers but more fruits than hermaphrodites. These results suggested that females and hermaphrodites possess similar facilitation intensity, and female cushion A. polytrichoides may allocate more resources saved from pollen production to seed production, while hermaphrodites possibly allocate more resources to pollen production hence reducing seed production. The surface areas covered by beneficiaries produced less flowers and fruits than areas without beneficiaries. In addition, strong negative correlations between beneficiary cover and flower cover were detected for both females and hermaphrodites, but the correlation strength were similar for these two sex morphs. However, the correlation between beneficiary cover and fruit cover was only significantly negative for females, suggesting that beneficiary plants negatively affect fruit reproduction of females while have neutral effects on hermaphrodites. All the results suggest that to facilitate other beneficiaries can induce reproductive costs on cushion A. polytrichoides, with females possibly suffering greater cost than hermaphrodites. Such differentiation in reproductive costs between sex morphs, in long-term perspective, may imply sex imbalance in population dynamics.

4.
Sci China Life Sci ; 67(4): 789-802, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38057621

RESUMO

Foundational cushion plants can re-organize community structures and sustain a prominent proportion of alpine biodiversity, but they are sensitive to climate change. The loss of cushion species can have broad consequences for associated biota. The potential plant community changes with the population dynamics of cushion plants remain, however, unclear. Using eight plant communities along a climatic and community successional gradient, we assessed cushion population dynamics, the underlying ecological constraints and hence associated plant community changes in alpine communities dominated by the foundational cushion plant Arenaria polytrichoides. The population dynamics of Arenaria are attributed to ecological constraints at a series of life history stages. Reproductive functions are constrained by increasing associated beneficiary plants; subsequent seedling establishment is constrained by temperature, water and light availability, extreme climate events, and interspecific competition; strong competitive exclusion may accelerate mortality and degeneration of cushion populations. Along with cushion dynamics, species composition, abundance and community structure gradually change. Once cushion plants completely degenerate, previously cushion-dominated communities shift to relatively stable communities that are overwhelmingly dominated by sedges. Climate warming may accelerate the degeneration process of A. polytrichoides. Degeneration of this foundational cushion plant will possibly induce massive changes in alpine plant communities and hence ecosystem functions in alpine ecosystems. The assessment of the population dynamics of foundation species is critical for an effective conservation of alpine biodiversity.


Assuntos
Biodiversidade , Ecossistema , Plantas , Mudança Climática , Biota
5.
Front Bioeng Biotechnol ; 11: 1264563, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37829569

RESUMO

Flexible tactile sensors have the advantages of large deformation detection, high fault tolerance, and excellent conformability, which enable conformal integration onto the complex surface of human skin for long-term bio-signal monitoring. The breakthrough of flexible tactile sensors rather than conventional tactile sensors greatly expanded application scenarios. Flexible tactile sensors are applied in fields including not only intelligent wearable devices for gaming but also electronic skins, disease diagnosis devices, health monitoring devices, intelligent neck pillows, and intelligent massage devices in the medical field; intelligent bracelets and metaverse gloves in the consumer field; as well as even brain-computer interfaces. Therefore, it is necessary to provide an overview of the current technological level and future development of flexible tactile sensors to ease and expedite their deployment and to make the critical transition from the laboratory to the market. This paper discusses the materials and preparation technologies of flexible tactile sensors, summarizing various applications in human signal monitoring, robotic tactile sensing, and human-machine interaction. Finally, the current challenges on flexible tactile sensors are also briefly discussed, providing some prospects for future directions.

6.
Plant Divers ; 44(3): 231-242, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35769589

RESUMO

The Qinghai-Tibet Plateau (QTP) is an important cushion plant hotspot. However, the distribution of cushion plants on the QTP is unknown, as are the factors that drive cushion plant distribution, limiting our understanding of the evolution of cushion species in the region. In this study, we assessed spatial patterns of total cushion plant diversity (including taxonomic and phylogenetic) over the entire QTP and compared patterns of diversity of cushion plants with different typologies (i.e., compact vs. loose). We also examined how these patterns were related to climatic features. Our results indicate that the southern QTP hosts the highest total cushion plant richness, especially in the south-central Hengduan Mountains subregion. The total number of cushion species declines from south to north and from southeast to northwest. Compact cushion plants exhibit similar patterns as the total cushion plant richness, whereas loose cushion plants show random distribution. Cushion plant phylogenetic diversity showed a similar pattern as that of the total cushion plant richness. In addition, cushion plant phylogenetic community structure was clustered in the eastern and southwestern QTP, whereas random or overdispersed in other areas. Climatic features represented by annual energy and water trends, seasonality and extreme environmental factors, had significant effects on cushion plant diversity patterns but limited effects on the phylogenetic community structure, suggesting that climatic features indeed promote the formation of cushion plants. Because cushion plants play vital roles in alpine ecosystems, our findings not only promote our understanding of the evolution and formation of alpine cushion plant diversity but also provide an indispensable foundation for future studies on cushion plant functions and thus alpine ecosystem sustainability in the entire QTP region.

7.
Front Immunol ; 13: 934084, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35844489

RESUMO

M1-polarized macrophages can improve the body's immune function. This study aimed to explore the mechanism of Platycodon grandiflorus polysaccharide (PGPSt) degrading SOCS1/2 protein through autophagy and promoting M1 polarization in 3D4/21 cells. Immunoprecipitation, confocal laser scanning microscopy, flow cytometry, and intracellular co-localization were used to detect the expression of related phenotypic proteins and cytokines in M1-polarized cells. The results showed that PGPSt significantly promoted the mRNA expression of IL-6, IL-12, and TNF-α and enhanced the protein expression of IL-6, IL-12, TNF-α, IL-1ß, iNOS, CD80, and CD86, indicating that PGPSt promoted M1 polarization in 3D4/21 cells. Next, the effect of the PGPSt autophagy degradation of SOCS1/2 on the M1 polarization of 3D4/21 cells was detected. The results showed that PGPSt significantly downregulated the expression level of SOCS1/2 protein, but had no obvious effect on the mRNA expression level of SOCS1/2, indicating that PGPSt degraded SOCS1/2 protein by activating the lysosome system. Further research found that under the action of 3-MA and BafA1, PGPSt upregulated LC3B II and downregulated SOCS1/2 protein expression, which increased the possibility of LC3B, the key component of autophagy, bridging this connection and degrading SOCS1/2. The interaction between SOCS1/2 and LC3 was identified by indirect immunofluorescence and Co-IP. The results showed that the co-localization percentage of the two proteins increased significantly after PGPSt treatment, and LC3 interacted with SOCS1 and SOCS2. This provides a theoretical basis for the application of PGPSt in the treatment or improvement of diseases related to macrophage polarization by regulating the autophagy level.


Assuntos
Platycodon , Autofagia , Interleucina-12/farmacologia , Interleucina-6/farmacologia , Platycodon/genética , Polissacarídeos/farmacologia , RNA Mensageiro , Proteína 1 Supressora da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/genética , Fator de Necrose Tumoral alfa/farmacologia
8.
Ecol Evol ; 11(23): 17397-17408, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34938516

RESUMO

The fragility and sensitivity to climate change of alpine ecosystems make it difficult to maintain the stability of their plant communities. Thus, it is important to determine which plant propagules are stored in the soils in order to understand community recruitment potential, especially under different environmental conditions. Based on a soil seed germination and seedling cultivation experiment, we aimed to identify differences in the soil seed attributes between three typical habitat types in the alpine subnival ecosystems of the Himalaya-Hengduan Mountains and hence to predict the community recruitment potential of each of these different communities. We found that the seed assemblages in the soils differed between habitats. The most abundant taxa were from the genera Saxifraga, Kobresia, Arenaria, Polygonum, Draba, and Viola, while the taxa with lowest abundance were Apiaceae, Campanulaceae, Circaea, Crassulaceae, and Gentiana. Different habitats exhibited variable soil seed richness, diversity, and density. However, the patterns differed between study sites. Specifically, at Baima (BM) and Shika (SK) snow mountains, soil seed richness, diversity, and density were generally highest in grassland, followed by rock bed and bare ground. In contrast, on Jiaozi (JZ) snow mountain, the rock bed supported the highest soil seed richness and density, followed by grassland and bare ground. These results suggest that the attributes of habitats and communities can both affect the accumulation of soil seeds. Bare ground supports the lowest seed diversity and density but also harbors the most empty niches. We, therefore, predict that, once the thermal conditions become suitable as a result of global warming, this habitat has the potential to see greater changes than grassland and rock bed in terms of community recruitment.

9.
Hepat Mon ; 16(7): e34588, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27642345

RESUMO

BACKGROUND: Radiofrequency ablation (RFA) and microwave ablation (MWA) are the most frequently used thermal ablation methods for the treatment of liver cancer. Liver abscess is a common and severe complication of thermal ablation treatment. OBJECTIVES: The objective of this study was to determine the incidence and risk factors of liver abscess formation after thermal ablation of liver cancer. MATERIALS AND METHODS: The clinical data of 423 patients who underwent 691 thermal ablation procedures for liver cancer were collected in order to retrospectively analyze the basic characteristics, incidence, and risk factors associated with liver abscess formation. Patients with multiple risk factors for liver abscess formation were enrolled in a risk factor group, and patients with no risk factors were enrolled in a control group. The chi-square test and multiple logistic regression analysis were used to analyze the relationship between the occurrence of liver abscesses and potential risk factors. RESULTS: Two hundred and eight patients underwent 385 RFA procedures, and 185 patients underwent 306 MWA procedures. The total incidence of liver abscesses was 1.7%, while the rates in the RFA group (1.8%) and MWA groups (1.6%) were similar (P > 0.05). The rates of liver abscesses in patients who had child-pugh class B and class C cirrhosis (P = 0.0486), biliary tract disease (P = 0.0305), diabetes mellitus (P = 0.0344), and porta hepatis tumors (P = 0.0123) were 4.0%, 6.7%, 6.5%, and 13.0%, respectively. There was a statistically significant difference between these four groups and the control group (all P < 0.05). The incidence of liver abscesses in the combined ablation and percutaneous ethanol injection (PEI) group (P = 0.0026) was significantly lower than that of the ablation group (P < 0.05). CONCLUSIONS: The incidence of liver abscesses after liver cancer thermal ablation is low. Child-Pugh Class B and Class C cirrhosis, biliary tract disease, diabetes mellitus, and porta hepatis tumors are four significant risk factors. Combined ablation and PEI reduces the rate of liver abscesses.

10.
Oncol Rep ; 34(6): 3231-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26503019

RESUMO

Our previous study reported that ADAM12 was highly expressed in small cell lung cancer (SCLC) and could be an effective marker for diagnosis and prognosis. Yet, the reason for the high expression of ADAM12 in SCLC requires further elucidation. Transcription factor E2F1 has been receiving increasing attention due to the complexity and diversity of its function in cancer. In the present study, the expression of ADAM12 was significantly decreased following silencing of E2F1 expression by siRNA, thus indicating that E2F1 may regulate the expression of ADAM12 at the level of transcription. Chromatin immunoprecipitation-to-sequence analysis identified three binding sites for E2F1 in the locus for ADAM12. They were Chr10: 128010444-128011026, located in the intron of ADAM12, named seq0; Chr10: 128076927­128078127, located in the promoter of ADAM12, named seq1; and Chr10: 128086195­128086876, located in the upstream 20 kb from the transcription start site of ADAM12, named: seq2. Dual­luciferase reporter experiments revealed that seq1 not seq0 and seq2 was able to promote the expression of luciferase. Notably, co-transfection of E2F1 significantly increased the activity of seq1 not seq0 and seq2, but quantitative polymerase chain reaction results showed that seq0, seq1 and seq2 could recruit E2F1, indicating that the influence of E2F1 in regulating the expression of ADAM12 was complex. Sequence analysis clarified that seq1 was a part of the ADAM12 promoter, yet the functions of seq0 and seq2 were unknown. Fusion fragments containing seq0-seq1 or seq2-seq1 were analyzed in luciferase constructs. Compared with seq1 alone, the activities of these fusion fragments were non-significantly reduced. The activities of fusion fragments were significantly decreased following co-transfection with E2F1. Thus, the present findings support the conclusion that the E2F1 transcription factor regulates the expression of ADAM12 by binding differential cis-acting elements.


Assuntos
Proteínas ADAM/biossíntese , Fator de Transcrição E2F1/biossíntese , Proteínas de Membrana/biossíntese , Sequências Reguladoras de Ácido Nucleico/genética , Carcinoma de Pequenas Células do Pulmão/genética , Proteínas ADAM/genética , Proteína ADAM12 , Sítios de Ligação , Linhagem Celular Tumoral , Fator de Transcrição E2F1/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Membrana/genética , Regiões Promotoras Genéticas , Ligação Proteica/genética , RNA Interferente Pequeno , Carcinoma de Pequenas Células do Pulmão/patologia
11.
Chem Commun (Camb) ; (2): 146-7, 2004 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-14737521

RESUMO

The reaction of phosphanylidene-[sigma](4)-phosphoranes ArP=PMe(3)(Ar = 2,6-Mes(2)C(6)H(3) or 2,4,6-t-Bu(3)C(6)H(2)) with select ortho-quinones yields 1,3,2-dioxophospholanes, one of which shows interesting [small pi]-stacking of the aromatic groups in the solid state.

12.
Inorg Chem ; 46(5): 1694-703, 2007 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-17243672

RESUMO

An expedient tandem deprotonation-trapping protocol was employed to prepare a tris(difluoroboronyl) complex of a triferrocenyl ligand that is geometrically analogous to substituted triphenylenes. A triple Schiff base condensation reaction between 1,3,5-triformylphloroglucinol and aminoferrocene afforded the tris(N-salicylideneamine) adducts 5a + 5b in ca. 1:1 ratio. The keto-enamine tautomeric core of this isomeric mixture could be converted to a common enolate-imine intermediate. Subsequent trapping with BF3.Et2O cleanly afforded the tris(difluoroboronyl) adduct 6 in essentially quantitative yield. The electronic and structural properties of this new class of ferrocene compounds were investigated using various methods including UV-vis, cyclic voltammetry (CV), differential pulse voltammetry (DPV), and X-ray crystallography. In CH2Cl2-CH3CN, 6 displayed a reversible three-electron oxidation process at E1/2ox = +210 mV (vs Fc/Fc+). Despite the sharing of a common [pi,pi]/[n,pi]-conjugated core, no significant electronic communication was observed among the three ferrocenyl units in 6 under either CV or DPV conditions. On the other hand, the broad oxidation wave of 5a + 5b at E1/2ox = +60 mV in CH2Cl2-CH3CN was comprised of at least two major components at +20 and +90 mV, which collapsed to become a single peak in DMF electrolyte, despite that the ratios between the two isomers 5a,b remained essentially invariant to the change in solvent.


Assuntos
Alcinos/química , Compostos Ferrosos/síntese química , Bases de Schiff/química , Cristalografia por Raios X , Eletroquímica , Compostos Ferrosos/química , Ligantes , Espectroscopia de Ressonância Magnética/métodos , Metalocenos , Modelos Moleculares , Estrutura Molecular , Oxirredução , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta/métodos , Estereoisomerismo
13.
Langmuir ; 21(7): 3104-5, 2005 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-15779991

RESUMO

Hematite nanoparticles have been functionalized with a self-assembled monolayer of undecanoic acid (UA) by covalent attachment via siloxane groups. The number density of carboxylic/carboxylate groups on the surface was determined by titration, yielding values on the order of 10(14) UA molecules/cm(2) and thus consistent with a closed-packed monolayer. The ability of these functionalized particles to adsorb Cd(2+) in the ppm range was demonstrated using in situ anodic stripping voltammetry.


Assuntos
Metais/química , Nanoestruturas/química , Adsorção , Íons/química , Magnetismo , Microscopia Eletrônica de Transmissão , Nanoestruturas/ultraestrutura , Análise Espectral , Temperatura , Titulometria
14.
Inorg Chem ; 42(18): 5468-70, 2003 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-12950188

RESUMO

A soluble (E)-poly(p-phenylenephosphaalkene) having sterically encumbering ligands has been prepared by a phospha-Wittig reaction. This material exhibits a bathochromic shift with respect to E-PPV and with respect to representative model oligomers. We also report the first fluorescence study of a poly(p-phenylenephosphaalkene) and find that this material exhibits fluorescence, though with modest intensity relative to similarly sized carbon-based analogues.

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