Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 258
Filtrar
1.
Nano Lett ; 24(14): 4117-4123, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38509030

RESUMO

Magnetic skyrmions, topologically nontrivial whirling spin textures at nanometer scales, have emerged as potential information carriers for spintronic devices. The ability to efficiently create and erase magnetic skyrmions is vital yet challenging for such applications. Based on first-principles studies, we find that switching between intrinsic magnetic skyrmion and high-temperature ferromagnetic states can be achieved in the two-dimensional van der Waals (vdW) multiferroic heterostructure CrSeI/In2Te3 by reversing the ferroelectric polarization of In2Te3. The core mechanism of this switching is traced to the controllable magnetic anisotropy of CrSeI influenced by the ferroelectric polarization of In2Te3. We propose a useful descriptor linking the presence of magnetic skyrmions to magnetic parameters and validate this connection through studies of a variety of similar vdW multiferroic heterostructures. Our work demonstrates that manipulating magnetic skyrmions via tunable magnetic anisotropies in vdW multiferroic heterostructures represents a highly promising and energy-efficient strategy for the future development of spintronics.

2.
Nano Lett ; 24(10): 3257-3266, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38426843

RESUMO

The extracellular matrix (ECM) orchestrates cell behavior and tissue regeneration by modulating biochemical and mechanical signals. Manipulating cell-material interactions is crucial for leveraging biomaterials to regulate cell functions. Yet, integrating multiple cues in a single material remains a challenge. Here, near-infrared (NIR)-controlled multifunctional hydrogel platforms, named PIC/CM@NPs, are introduced to dictate fibroblast behavior during wound healing by tuning the matrix oxidative stress and mechanical tensions. PIC/CM@NPs are prepared through cell adhesion-medicated assembly of collagen-like polyisocyanide (PIC) polymers and cell-membrane-coated conjugated polymer nanoparticles (CM@NPs), which closely mimic the fibrous structure and nonlinear mechanics of ECM. Upon NIR stimulation, PIC/CM@NPs composites enhance fibroblast cell proliferation, migration, cytokine production, and myofibroblast activation, crucial for wound closure. Moreover, they exhibit effective and toxin removal antibacterial properties, reducing inflammation. This multifunctional approach accelerates healing by 95%, highlighting the importance of integrating biochemical and biophysical cues in the biomaterial design for advanced tissue regeneration.


Assuntos
Materiais Biocompatíveis , Cicatrização , Espécies Reativas de Oxigênio , Materiais Biocompatíveis/farmacologia , Polímeros/farmacologia , Matriz Extracelular , Hidrogéis/farmacologia , Antibacterianos/farmacologia
3.
Opt Express ; 32(5): 6963-6976, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439389

RESUMO

Polarization modulation of electromagnetic waves plays an important role in the field of optics and optoelectronics. Current polarization optics are typically limited to the modulation in a single transverse plane. However, manipulating polarization along the longitudinal direction is also important for full-space polarization modulation. Here, we propose two kinds of all-dielectric terahertz metasurfaces for longitudinally spatial polarization manipulation. The metasurfaces are capable of controlling polarization along the propagation path, namely: i) a longitudinal bifocal metalens with different polarization states at each focal point, and ii) a versatile metalens can simultaneously generate a uniformly polarized focused beam and a vector beam with varying polarization along the propagation path. Furthermore, the measurement of the dielectric thickness is demonstrated based on the polarization modulation feature of the metalens. The proposed metasurfaces allow for effective polarization state alteration along the propagation path, exhibiting significant potential for applications in versatile light-matter interactions, optical communications, and quantum optics.

4.
Molecules ; 29(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38542876

RESUMO

Endothelial inflammation is a multifaceted physiological process that plays a pivotal role in the pathogenesis and progression of diverse diseases, encompassing but not limited to acute lung infections like COVID-19, coronary artery disease, stroke, sepsis, metabolic syndrome, certain malignancies, and even psychiatric disorders such as depression. This inflammatory response is characterized by augmented expression of adhesion molecules and secretion of pro-inflammatory cytokines. In this study, we discovered that saponins from Allium macrostemon bulbs (SAMB) effectively inhibited inflammation in human umbilical vein endothelial cells induced by the exogenous inflammatory mediator lipopolysaccharide or the endogenous inflammatory mediator tumor necrosis factor-α, as evidenced by a significant reduction in the expression of pro-inflammatory factors and vascular cell adhesion molecule-1 (VCAM-1) with decreased monocyte adhesion. By employing the NF-κB inhibitor BAY-117082, we demonstrated that the inhibitory effect of SAMB on VCAM-1 expression may be attributed to the NF-κB pathway's inactivation, as characterized by the suppressed IκBα degradation and NF-κB p65 phosphorylation. Subsequently, we employed a murine model of lipopolysaccharide-induced septic acute lung injury to substantiate the potential of SAMB in ameliorating endothelial inflammation and acute lung injury in vivo. These findings provide novel insight into potential preventive and therapeutic strategies for the clinical management of diseases associated with endothelial inflammation.


Assuntos
Lesão Pulmonar Aguda , Cebolinha-Francesa , Medicamentos de Ervas Chinesas , Saponinas , Humanos , Animais , Camundongos , NF-kappa B/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo , Saponinas/farmacologia , Lipopolissacarídeos/toxicidade , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle , Células Endoteliais da Veia Umbilical Humana , Fator de Necrose Tumoral alfa/farmacologia , Lesão Pulmonar Aguda/tratamento farmacológico , Mediadores da Inflamação/metabolismo
5.
Molecules ; 29(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474581

RESUMO

Endothelial pro-inflammatory activation is pivotal in cardiac ischemia-reperfusion (I/R) injury pathophysiology. The dried flower bud of Edgeworthia gardneri (Wall.) Meisn. (EG) is a commonly utilized traditional Tibetan medicine. However, its role in regulating endothelium activation and cardiac I/R injury has not been investigated. Herein, we showed that the administration of EG ethanolic extract exhibited a potent therapeutic efficacy in ameliorating cardiac endothelial inflammation (p < 0.05) and thereby protecting against myocardial I/R injury in rats (p < 0.001). In line with the in vivo findings, the EG extract suppressed endothelial pro-inflammatory activation in vitro by downregulating the expression of pro-inflammatory mediators (p < 0.05) and diminishing monocytes' firm adhesion to endothelial cells (ECs) (p < 0.01). Mechanistically, we showed that EG extract inhibited the nuclear factor kappa-B (NF-κB), c-Jun N-terminal kinase (JNK), extracellular regulated protein kinase (ERK), and p38 mitogen-activated protein kinase (MAPK) signaling pathways to attenuate EC-mediated inflammation (p < 0.05). Collectively, for the first time, this study demonstrated the therapeutic potential of EG ethanolic extract in alleviating I/R-induced inflammation and the resulting cardiac injury through its inhibitory role in regulating endothelium activation.


Assuntos
Traumatismo por Reperfusão Miocárdica , Thymelaeaceae , Ratos , Animais , Células Endoteliais/metabolismo , NF-kappa B/metabolismo , Inflamação/tratamento farmacológico , Extratos Vegetais/farmacologia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Endotélio/metabolismo , Thymelaeaceae/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
Small ; 19(18): e2207457, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36737834

RESUMO

The combination of biomolecules and synthetic polymers provides an easy access to utilize advantages from both the synthetic world and nature. This is not only important for the development of novel innovative materials, but also promotes the application of biomolecules in various fields including medicine, catalysis, and water treatment, etc. Due to the rapid progress in synthesis strategies for polymer nanomaterials and deepened understanding of biomolecules' structures and functions, the construction of advanced polymer-based biohybrid nanostructures (PBBNs) becomes prospective and attainable. Polymerization-induced self-assembly (PISA), as an efficient and versatile technique in obtaining polymeric nano-objects at high concentrations, has demonstrated to be an attractive alternative to existing self-assembly procedures. Those advantages induce the focus on the fabrication of PBBNs via the PISA technique. In this review, current preparation strategies are illustrated based on the PISA technique for achieving various PBBNs, including grafting-from and grafting-through methods, as well as encapsulation of biomolecules during and subsequent to the PISA process. Finally, advantages and drawbacks are discussed in the fabrication of PBBNs via the PISA technique and obstacles are identified that need to be overcome to enable commercial application.


Assuntos
Nanoestruturas , Polímeros , Polimerização , Polímeros/química , Estudos Prospectivos , Nanoestruturas/química , Catálise
7.
Phys Rev Lett ; 131(18): 186703, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37977650

RESUMO

The understanding and manipulation of anisotropic Gilbert damping is crucial for both fundamental research and versatile engineering and optimization. Although several works on anisotropic damping have been reported, no direct relationship between the band structure and anisotropic damping was established. Here, we observed an anisotropic damping in Fe/GeTe manipulated by the symmetric band structures of GeTe via angle-resolved photoemission spectroscopy. Moreover, the anisotropic damping can be modified by the symmetry of band structures. Our Letter provides insightful understandings of the anisotropic Gilbert damping in ferromagnets interfaced with Rashba semiconductors and suggests the possibility of manipulating the Gilbert damping by band engineering.

8.
BMC Public Health ; 23(1): 2239, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957572

RESUMO

OBJECTIVE: To analyze factors influencing the underestimation of noise-induced permanent threshold shift (NIPTS) among manufacturing workers, providing baseline data for revising noise exposure standard. DESIGN: A cross-sectional study was designed with 2702 noise-exposed workers from 35 enterprises from 10 industries. Personal noise exposure level(LAeq,8h) and noise kurtosis level were determined by a noise dosimeter. Questionnaires and hearing loss tests were performed for each subject. The predicted NIPTS was calculated using the ISO 1999:2013 model for each participant, and the actual measured NIPTS was corrected for age and sex. The factors influencing the underestimation of NIPTS were investigated. RESULTS: The predicted NIPTS at each test frequency (0.5, 1, 2, 3, 4, or 6kHz) and mean NIPTS at 2, 3, 4, and 6kHz (NIPTS2346) using the ISO 1999:2013 model were significantly lower than their corresponding measured NIPTS, respectively (P < 0.001). The ISO model significantly underestimated the NIPTS2346 by 12.36 dB HL. The multiple linear regression analysis showed that noise exposure level, exposure duration, age, and kurtosis could affect the degree of underestimation of NIPTS2346. The generalized additive model (GAM) with (penalized) spline components showed nonlinear relationships between critical factors (age, exposure duration, noise level, and kurtosis) and the underestimated NIPTS2346.The underestimated NIPTS2346 decreased with an increase in exposure duration (especially over ten years). There was no apparent trend in the underestimated NIPTS2346 with age. The underestimated NIPTS2346 decreased with the increased noise level [especially > 90 dB(A)]. The underestimated NIPTS2346 increased with an increase in noise kurtosis after adjusting for the noise exposure level and exposure duration and ultimately exhibiting a linear regression relationship. CONCLUSIONS: The ISO 1999 predicting model significantly underestimated the noise-induced hearing loss among manufacturing workers. The degree of underestimation became more significant at the noise exposure condition of fewer than ten years, less than 90 dB(A), and higher kurtosis levels. It is necessary to apply kurtosis to adjust the underestimation of hearing loss and consider the applying condition of noise energy metrics when using the ISO predicting model.


Assuntos
Surdez , Perda Auditiva Provocada por Ruído , Ruído Ocupacional , Doenças Profissionais , Exposição Ocupacional , Humanos , Estudos Transversais , Limiar Auditivo , Perda Auditiva Provocada por Ruído/diagnóstico , Perda Auditiva Provocada por Ruído/epidemiologia , Perda Auditiva Provocada por Ruído/etiologia , Ruído , Ruído Ocupacional/efeitos adversos , Doenças Profissionais/diagnóstico , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos
9.
J Invertebr Pathol ; 201: 108023, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37995901

RESUMO

The effects of chemical factors on the infectivity of DIV1 have not been fully accessed yet. In order to investigate the stability of DIV1 to strong brine, pH, and other chemical conditions, we conducted a bioassay using clinically healthy Penaeus vannamei individuals. DIV1 inoculum was exposed to various chemical conditions, and the infectivity of DIV1 was determined through intramuscular injection. The results showed that DIV1 lost its infectivity when exposed to strong brine, specifically in a 3 mol/L NaCl solution for a duration of 1 h. Moreover, DIV1 was found to be inactivated within 1 h when subjected to pH levels below 3.1 or above 9.6. Additionally, both Triton X-100 and 1 % formaldehyde demonstrated the ability to inactivate DIV1. These results provide valuable insights into the tolerance of DIV1 towards certain chemical factors, serving as a reference for the establishment of biosecurity measures against DIV1.


Assuntos
Penaeidae , Animais , Octoxinol , Injeções Intramusculares
10.
Molecules ; 28(22)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38005247

RESUMO

The Nod-like receptor family PYRIN domain containing 3 (NLRP3) inflammasome is a multiprotein signaling complex that plays a pivotal role in innate immunity, and the dysregulated NLRP3 inflammasome activation is implicated in various diseases. Tiliroside is a natural flavonoid in multiple medicinal and dietary plants with known anti-inflammatory activities. However, its role in regulating NLRP3 inflammasome activation and NLRP3-related disease has not been evaluated. Herein, it was demonstrated that tiliroside is inhibitory in activating the NLRP3 inflammasome in macrophages. Mechanistically, tiliroside promotes AMP-activated protein kinase (AMPK) activation, thereby leading to ameliorated mitochondrial damage as evidenced by the reduction of mitochondrial reactive oxygen species (ROS) production and the improvement of mitochondrial membrane potential, which is accompanied by attenuated NLRP3 inflammasome activation in macrophages. Notably, tiliroside potently attenuated lipopolysaccharide (LPS)-induced acute lung injury in mice, which has been known to be NLRP3 inflammasome dependent. For the first time, this study identified that tiliroside is an NLRP3 inflammasome inhibitor and may represent a potential therapeutic agent for managing NLRP3-mediated inflammatory disease.


Assuntos
Lesão Pulmonar Aguda , Inflamassomos , Camundongos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Macrófagos/metabolismo , Flavonoides/metabolismo , Lesão Pulmonar Aguda/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Lipopolissacarídeos/farmacologia
11.
Crit Rev Food Sci Nutr ; 62(19): 5307-5321, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33635174

RESUMO

Inflammatory bowel disease (IBD) is a chronic gastro-intestinal disorders of unknown etiology. There are several drugs approved for treating IBD patients with active disease, including first-line use of aminosalicylates, and secondary choices of immunomodulators and other therapies. These medications might manage disease symptoms, but have also shown significant side-effects in IBD patients. Tea is the second largest beverage in the world and its main active ingredients including tea polyphenols, polysaccharides and tea pigments have been shown promising anti-inflammatory and antioxidant properties. In this review, we summarize the influence of different tea varieties including green tea, black tea and dark tea as potential nutritional therapy for preventing and treating IBD, and discuss the mechanisms of tea ingredients involved in the regulation of oxidative stress, inflammation, signaling pathways, and gut microbiota that could benefit for IBD disease management. Our observation directs further basic and clinical investigations on tea polyphenols and their derivatives as novel IBD therapeutic agents.


Assuntos
Doenças Inflamatórias Intestinais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Chá/metabolismo
12.
Molecules ; 27(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36500719

RESUMO

Crawfish can be easily spoiled due to their rich nutrition and high water content, which is difficult to preserve. In this study, the dominant spoilage organisms in crawfish which were stored at 4 °C in vacuum packaging were identified by high-throughput sequencing technology; after sequencing the full-length 16S rRNA gene, the changes in the bacterial community structure, diversity and quality (texture, flavor, etc.) were analyzed. Our results reflected that the specific spoilage organisms (SSOs) of crawfish were Aeromonas sobria, Shewanella putrefaciens, Trichococcus pasteurii and Enterococcus aquimarinus, since their abundances significantly increased after being stored for 12 days at 4 °C under vacuum conditions. At the same time, the abundance and diversity of the microbial community decreased with storage time, which was related to the rapid growth of the dominant spoilage organisms and the inhibition of other kinds of microorganisms at the end of the spoilage stage. Function prediction results showed that the gene which contributed to metabolism influenced the spoilage process. Moreover, the decline in texture of crawfish was negatively correlated to the richness of SSOs; this may be because SSOs can produce alkaline proteases to degrade the myofibrillar protein. On the contrary, the unpleasant flavor of crawfish, resulting from volatile flavor compounds such as S-containing compounds and APEOs, etc., is negatively correlated to the richness of SSOs, due to the metabolism of SSOs by secondary metabolites such as terpenoids, polyketides and lips, which can lead to decarboxylation, deamination and enzymatic oxidation. These results are very important to achieve the purpose of targeted inhibition of crawfish spoilage at 4 °C in vacuum packaging.


Assuntos
Embalagem de Alimentos , Microbiota , Animais , RNA Ribossômico 16S/genética , Embalagem de Alimentos/métodos , Microbiologia de Alimentos , Vácuo , Astacoidea , Conservação de Alimentos/métodos
13.
Appl Microbiol Biotechnol ; 105(10): 4269-4284, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33990856

RESUMO

Enterococcus faecium WEFA23 was previously found effectively against adherence and colonization of Listeria monocytogenes CMCC54007, which might be closely related to its surface layer protein (SLP). In this study, the protective of SLP of E. faecium WEFA23 against infection of L. monocytogenes CMCC54007 was systemically investigated. In vitro assay showed that SLP actively inhibited L. monocytogenes internalization into Caco-2 cell line, with decreasing mRNA level of pro-inflammation cytokines and virulence factors and restoring destroyed intestinal barrier. In vivo assay through excluding SLP of E. faecium WEFA23 by 5 M LiCl represented that SLP increased body weight, reduced mortality and cell counts of L. monocytogenes CMCC54007 in tissues of mice. Further researches showed that SLP protected against L. monocytogenes CMCC54007 infection by modulation of intestinal permeability and immunity, namely, it decreased fluorescein isothiocyanate (FITC)-Dextran in serum, ameliorated destroyed colon structure, and increased number of goblet cells and protein level of TJ protein (Claudin-1, Occludin, and ZO-1) in colon. For immunity, SLP decreased number of CD4+ and CD8+ T cells in liver, mRNA level, and content of pro-inflammatory factors IL-6, IL-1ß, IFN-γ ,TNF-α, and NO, and restored the structure of liver and spleen. Key Points•SLP of E. faecium inhibited L. monocytogenes internalization and colonization•SLP of E. faecium ameliorated host intestinal barrier dysfunction•SLP of E. faecium decreased pro-inflammatory cytokines and cells.


Assuntos
Enterococcus faecium , Listeria monocytogenes , Listeriose , Animais , Linfócitos T CD8-Positivos , Células CACO-2 , Humanos , Listeriose/prevenção & controle , Proteínas de Membrana , Camundongos , Permeabilidade
14.
Angew Chem Int Ed Engl ; 60(20): 11098-11103, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33565244

RESUMO

Glyco-assemblies derived from amphiphilic sugar-decorated block copolymers (ASBCs) have emerged prominently due to their wide application, for example, in biomedicine and as drug carriers. However, to efficiently construct these glyco-assemblies is still a challenge. Herein, we report an efficient technology for the synthesis of glyco-inside nano-assemblies by utilizing RAFT polymerization of a galactose-decorated methacrylate for polymerization-induced self-assembly (PISA). Using this approach, a series of highly ordered glyco-inside nano-assemblies containing intermediate morphologies were fabricated by adjusting the length of the hydrophobic glycoblock and the polymerization solids content. A specific morphology of complex vesicles was captured during the PISA process and the formation mechanism is explained by the morphology of its precursor and intermediate. Thus, this method establishes a powerful route to fabricate glyco-assemblies with tunable morphologies and variable sizes, which is significant to enable the large-scale fabrication and wide application of glyco-assemblies.


Assuntos
Galactose/síntese química , Nanopartículas/química , Galactose/química , Estrutura Molecular , Tamanho da Partícula , Polimerização , Propriedades de Superfície
15.
FASEB J ; 33(2): 2782-2795, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30307764

RESUMO

Fenvalerate (FEN), a mainstream pyrethroid pesticide, was initially recommended as a low-toxicity agent for controlling agricultural and domestic pests. Despite the widespread use of FEN worldwide, little data are available on FEN-induced hepatic lesions and molecular mechanisms. In the present study, we first performed an occupational cross-sectional study on FEN factory workers and found that the levels of serum alanine aminotransferase (ALT) and total antioxidant capacity increased, whereas malondialdehyde decreased in laborers in the working areas where the levels of airborne FEN were much higher compared with the office area. The results were then confirmed by animal experiments that abnormal hepatic histology, increased ALT level, and compromised hepatic oxidative capability were observed in rats exposed to a high concentration of FEN. Furthermore, the bioinformatics analysis of gene microarray in rat liver tissue showed that FEN significantly changed the expressions of genes related to the regulation of intracellular calcium ion homeostasis and the calcium signal pathway. Finally, the functional experiments in Buffalo rat liver (BRL) cells demonstrated that FEN first activated ERK MAPK, followed by IKK and NF-κB, which triggered the transcription of genes responsible for accelerating an overload of intracellular calcium ions, prompted reactive oxygen species generation in the mitochondria, and finally, induced hepatic cellular apoptosis. The calcium signaling pathway and in particular, an overload of intracellular calcium play a critical role in this pathophysiological process via the ERK/IKK/NF-κB pathway. Our study furthers the understanding of the mechanism of FEN-induced hepatic injuries and may have implications in the prevention and control of liver diseases induced by environmental pesticides.-Qiu, L.-L., Wang, C., Yao, S., Li, N., Hu, Y., Yu, Y., Xia, R., Zhu, J., Ji, M., Zhang, Z., Wang S.-L. Fenvalerate induces oxidative hepatic lesions through an overload of intracellular calcium triggered by the ERK/IKK/NF-κB pathway.


Assuntos
Cálcio/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nitrilas/efeitos adversos , Exposição Ocupacional/efeitos adversos , Piretrinas/efeitos adversos , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Estudos Transversais , Feminino , Perfilação da Expressão Gênica , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Inseticidas/efeitos adversos , Masculino , NF-kappa B/genética , NF-kappa B/metabolismo , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley
16.
Arch Microbiol ; 202(1): 181-189, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31562551

RESUMO

The structure and diversity of microbial communities in the leaves of Cinnamomum camphora at different growth stages were studied by high-throughput sequencing. Moreover, the relationships between microbial communities and borneol content were analyzed in this paper. The results indicated that the community structure of endophytic bacteria in C. camphora exhibited temporal variations, with the microbial diversity presented as follows: T1 (low content period) > T3 (peak period) > T2 (small peak period). The population of endophytic bacteria and the ratio of primary metabolism in the leaves of C. camphora were T2 > T1 > T3, while the metabolic intensity of endophytic bacterial terpenoids and polyketides was T3 > T2 > T1, which had the same trend as borneol content in C. camphora. The metabolic ratio of terpenoids and polyketides in T3 was 7.44% higher than that in T1, while that in T2 was 4.10% higher than that in T1. The abundance and diversity of Clostridium_sensu_stricto_1, Ochrobactrum, Escherichia-Shigella, Pseudomonas, and Massilia significantly promoted the content of terpenoids in C. camphora. Together, those results provide the first evidence that borneol content and potential metabolic intensity in leaves of C. camphora greatly depend on microbial communities composition and diversity.


Assuntos
Fenômenos Fisiológicos Bacterianos , Biodiversidade , Cinnamomum camphora/microbiologia , Folhas de Planta/microbiologia , Bactérias/classificação , Cinnamomum camphora/química , Cinnamomum camphora/metabolismo , Folhas de Planta/metabolismo
17.
Appl Microbiol Biotechnol ; 104(12): 5493-5504, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32314005

RESUMO

The bacterium-bacterium interaction between pathogenic and probiotic Enterococcus as well as the bacterium-host interaction between Enterococcus and intestinal epithelium has drawn increasing attentions, but the influence of those interactions on host pregnancy remains largely unexplored. In the present study, we evaluated the effects of probiotic E. faecalis Symbioflor 1 or/and pathogenic E. faecalis OG1RF on the miscarriage of pregnant mice. Using in vitro assays of competition and exclusion and displacement, antagonistic property of E. faecalis Symbioflor 1 against E. faecalis OG1RF was observed, and the former inhibited the translocation of the later in vivo. The rate of miscarriage induced by E. faecalis OG1RF challenge was significantly reduced by 28% with E. faecalis Symbioflor 1 intervention; and the tissue integrity of ileum, colon, uterus, and placenta and placental blood cell density in pregnant mice were drastically improved by such probiotic intervention. Compared with the controls, probiotic intervention significantly upregulated the level of IL-10 and TGF-ß, downregulated levels of IFN-γ, and increased progesterone level that reversed the trend of being Th1 predominance state reported for adverse pregnancy outcome at early pregnancy stage. In conclusion, E. faecalis Symbioflor 1 decreased the translocation of E. faecalis OG1RF, prevented pathogen-induced tissue damage, and changed Th1-Th2 homeostasis toward Th2 predominance during early pregnancy resulting in decreased miscarriage. KEY POINTS: •The mechanism of how probiotic E. faecalis Symbioflor 1 improves pregnancy of mice • Influence of interactions of pathogenic and probiotic Enterococcus on host pregnancy • E. faecalis Symbioflor 1 change Th1-Th2 homeostasis toward Th2 predominance.


Assuntos
Aborto Espontâneo/microbiologia , Aborto Espontâneo/prevenção & controle , Antibiose , Enterococcus faecalis/fisiologia , Probióticos/administração & dosagem , Células Th1/imunologia , Células Th2/imunologia , Animais , Translocação Bacteriana , Citocinas/imunologia , Enterococcus faecalis/patogenicidade , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Progesterona/sangue , Organismos Livres de Patógenos Específicos
18.
J Invertebr Pathol ; 172: 107347, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32119955

RESUMO

A fluorescent stain, calcofluor white (CFW), was used for detection of spores of the microsporidium Enterocytozoon hepatopenaei (EHP). EHP spores in suspension, in feces, or in the infected hepatopancreas of the shrimp Penaeus vannamei, can be easily stained with this chitin and cellulose binding dye to show distinct blue-white fluorescent oval walls. The dye does not stain the host tissues. EHP spores showed orange-red spots by staining with hematoxylin and phloxine (H&P) in the section. CFW staining provides a simple and rapid method for determining the presence of EHP spores in fecal or tissue samples.


Assuntos
Benzenossulfonatos/química , Enterocytozoon/isolamento & purificação , Penaeidae/microbiologia , Esporos Fúngicos/isolamento & purificação , Coloração e Rotulagem/métodos , Animais , Fezes/microbiologia , Hepatopâncreas/microbiologia
19.
J Invertebr Pathol ; 173: 107367, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32251642

RESUMO

Decapod iridescent virus 1 (DIV1) was proven to be the aetiological agent of a disease causing mass die-offs of shrimp, prawn and crayfish. The specific purpose of this study was to develop a new sensitive real-time PCR method for the specific detection of DIV1. A pair of primers that amplify a 142 bp fragment and a TaqMan probe were selected for the major capsid protein gene of DIV1. They were shown to be specific for DIV1 and did not react with other common shrimp pathogens or healthy shrimp DNA. The method could detect as virus levels as low as 1.2 copies of DIV1 plasmid DNA.


Assuntos
Iridoviridae/isolamento & purificação , Penaeidae/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Reação em Cadeia da Polimerase em Tempo Real/instrumentação , Sensibilidade e Especificidade , Carga Viral
20.
Entropy (Basel) ; 22(8)2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-33286598

RESUMO

We investigated the dynamics of a two-qutrit system in a correlated quantum channel. The partial correlations between consecutive actions of the channel can effectively postpone the phenomenon of distillability sudden death (DSD) and broaden the range of the time cutoff that indicates entanglement of the positive partial transpose states. Particularly, the negativity of the system will revive and DSD will disappear in the fully correlated channel.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA