Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 239
Filtrar
1.
J Sci Food Agric ; 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34625972

RESUMO

Flavonoids have a variety of biological activities that are beneficial to human health. However, due to low bioavailability, most flavonoids exert beneficial effects in the intestine through metabolism by the flora into a variety of structurally different derivatives. Also, flavonoids can modulate the type and structure of intestinal microorganisms to improve human health. It has been reported the development of depression is accompanied by the changes in the type and number of intestinal microorganisms, and gut microbes can significantly improve depressive symptoms through the gut-brain axis. Therefore, the interaction between flavonoids and intestinal microbes to alleviate depression was discussed. This article is protected by copyright. All rights reserved.

2.
BMC Cardiovasc Disord ; 21(1): 431, 2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34511074

RESUMO

BACKGROUND: Hyperlactatemia may be caused by increased production due to tissue hypoxia or non-hypoxia. The aim of this study was first to identify risk factors for postoperative hyperlactatemia (POHL) after Stanford type A acute aortic dissection surgery (AADS) and construct a predictive model, and second to evaluate the impact of POHL on prognosis. METHODS: This retrospective study involved patients undergoing AADS from January 2016 to December 2019 in Wuhan Union Hospital. Multivariate logistic regression analysis was performed to identify independent risk factors for POHL. A nomogram predicting POHL was established based on these factors and was validated in the original dataset. The receiver operating characteristic curve was drawn to assess the ability of postoperative lactate levels to predict the in-hospital mortality. RESULTS: A total of 188 patients developed POHL after AADS (38.6%). Male gender, surgery history, red blood cell transfusion and cardiopulmonary bypass time were identified as independent predictors. The C-index of the prediction model for POHL was 0.72, indicating reasonable discrimination. The model was well calibrated by visual inspection and goodness-of-fit test (Hosmer-Lemeshow χ2 = 10.25, P = 0.25). Decision and clinical impact curves of the model showed good clinical utility. The overall in-hospital mortality rate was 10.1%. Postoperative lactate levels showed a moderate predictive power for postoperative in-hospital mortality (C-index: 0.72). CONCLUSION: We developed and validated a prediction model for POHL in patients undergoing AADS, which may have clinical utility in personal risk evaluation and preventive interventions. The POHL could be a good predictor for in-hospital mortality.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34542394

RESUMO

A Gram-stain-positive, non-motile and short rod-shaped actinobacterium, designated strain LNNU 22110T, was isolated from the rhizosphere soil of the halophyte Suaeda aralocaspica (Bunge) Freitag and Schütze, which collected in Xinjiang, north-west China. Growth occurred at 10-45 °C, pH 6.0-10.0 and in the presence of 0-11 % NaCl (w/v). Based on the results of 16S rRNA gene sequence phylogenetic analyses, strain LNNU 22110T belonged to the genus Ruania and had 97.5 and 95.5 % sequence similarity to Ruania alba KCTC 19413T and Ruania albidiflava CGMCC 4.3142T, respectively. The digital DNA-DNA hybridization relatedness values between strain LNNU 22110T and R. alba KCTC 19413T and R. albidiflava CGMCC 4.3142T were 23.2 and 19.9 %, respectively. The highest average nucleotide identity value between strain LNNU 22110T and its closest related strain (R. alba KCTC 19413T) was 80.2 %, much lower than the species delineation threshold of 95-96 %. The genome of strain LNNU 22110T was 4.4 Mb, with a genomic DNA G+C content of 68.4 mol%. The diagnostic diamino acids in the peptidoglycan layer of strain LNNU 22110T were lysine, alanine, glycine, glutamic acid and aspartic acid. The predominant menaquinone was MK-8(H4). The major fatty acid (>10 %) was anteiso-C15 : 0. The polar lipid profile of strain LNNU 22110T included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, diacylated phosphatidyl dimannoside, one unidentified glycolipid and two unidentified phospholipids. According to the phenotypic, phylogenetic and chemotaxonomic results, strain LNNU 22110T is considered to represent a novel species of the genus Ruania, for which the name Ruania rhizosphaerae sp. nov. is proposed. The type strain is LNNU 22110T (=KCTC 39807T=CGMCC 1.17105T).


Assuntos
Chenopodiaceae , Rizosfera , Actinobacteria , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Microbiologia do Solo
4.
Nat Commun ; 12(1): 4849, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381032

RESUMO

Although various artificial protein nanoarchitectures have been constructed, controlling the transformation between different protein assemblies has largely been unexplored. Here, we describe an approach to realize the self-assembly transformation of dimeric building blocks by adjusting their geometric arrangement. Thermotoga maritima ferritin (TmFtn) naturally occurs as a dimer; twelve of these dimers interact with each other in a head-to-side manner to generate 24-meric hollow protein nanocage in the presence of Ca2+ or PEG. By tuning two contiguous dimeric proteins to interact in a fully or partially side-by-side fashion through protein interface redesign, we can render the self-assembly transformation of such dimeric building blocks from the protein nanocage to filament, nanorod and nanoribbon in response to multiple external stimuli. We show similar dimeric protein building blocks can generate three kinds of protein materials in a manner that highly resembles natural pentamer building blocks from viral capsids that form different protein assemblies.


Assuntos
Nanoestruturas/química , Proteínas/química , Cálcio/química , Ferritinas/química , Nanoestruturas/ultraestrutura , Nanotecnologia , Polietilenoglicóis/química , Multimerização Proteica , Thermotoga maritima
6.
Inorg Chem ; 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34212727

RESUMO

Metal-organic frameworks (MOFs) have appeared to be promising competitive candidates as crystalline porous materials for proton conduction. Explorations of the method of preparation of proton conductive MOFs and the proton transfer mechanism have enabled them to attract widespread attention, and tremendous efforts have been made to improve the proton conductivity of MOFs. On the basis of our previous work, we explicitly propose that ligand exchange can upgrade the proton conduction performance of MOFs. Using MOF-azo as the precursor, the proton conductivities of exchange products MOF-bpy and MOF-bpe increase by 3.5- and 2.8-fold, respectively. After the MOFs had been doped into the Nafion matrix to prepare composite membranes, the proton conduction performance of composite membranes filled with subproducts (2.6 × 10-2 and 1.95 × 10-2 S cm-1) is significantly better than that of a composite membrane filled with a parent product (1.12 × 10-2 S cm-1) under ambient conditions (without heating or humidifying). The ligand exchange strategy presented herein demonstrates great promise for the development of high-proton conductivity MOFs and MOF composites with expanded future applications.

7.
J Inorg Biochem ; 222: 111508, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34116426

RESUMO

Histone deacetylase inhibitors have often been used in combination treatment of various types of cancers due to their non-genotoxic epigenetic potential. Valproic acid (VPA) is a well-known histone deacetylase inhibitor. Conjugate of VPA with a phtoactive platinum diimine complex through an ester bond has been fabricated to potentiate the photocytotoxicity of the photosensitizer. Its capability to generate singlet oxygen, behavior in the presence of esterase, and photocytotoxicity in tumor cells have also been studied. The results revealed that the novel VPA-modified platinum diimine complex could produce singlet oxygen efficiently and release VPA in the presence of porcine liver esterase. The results also suggested that incorporation of VPA moiety into the platinum diimine complex might significantly enhance the cytotoxicity of the complex.

8.
Inorg Chem ; 60(12): 8826-8837, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34060309

RESUMO

How to deliver nitric oxide (NO) to a physiological target and control its release quantitatively is a key issue for biomedical applications. Here, a water-soluble nitrosylruthenium complex, [(CH3)4N][RuCl3(5cqn)(NO)] (H5cqn = 5-chloro-8-quinoline), was synthesized, and its structure was confirmed with 1H NMR and X-ray crystal diffraction. Photoinduced NO release was investigated with time-resolved Fourier transform infrared and electron paramagnetic resonance (EPR) spectroscopies. The binding constant of the [RuCl3(5cqn)(NO)]- complex with human serum albumin (HSA) was determined by fluorescence spectroscopy, and the binding mode was identified by X-ray crystallography of the HSA and Ru-NO complex adduct. The crystal structure reveals that two molecules of the Ru-NO complex are located in the subdomain IB, which is one of the major drug binding regions of HSA. The chemical structures of the Ru complexes were [RuCl3(5cqn)(NO)]- and [RuCl3(Glycerin)NO]-, in which the electron densities for all ligands to Ru are unambiguously identified. EPR spin-trapping data showed that photoirradiation triggered NO radical generation from the HSA complex adduct. Moreover, the near-infrared image of exogenous NO from the nitrosylruthenium complex in living cells was observed using a NO-selective fluorescent probe. This study provides a strategy to design an appropriate delivery system to transport NO and metallodrugs in vivo for potential applications.


Assuntos
Complexos de Coordenação/metabolismo , Óxido Nítrico/metabolismo , Compostos de Rutênio/metabolismo , Albumina Sérica Humana/metabolismo , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cristalografia por Raios X , Corantes Fluorescentes/química , Células HeLa , Humanos , Modelos Moleculares , Estrutura Molecular , Óxido Nítrico/química , Imagem Óptica , Processos Fotoquímicos , Compostos de Rutênio/química , Albumina Sérica Humana/química , Células Tumorais Cultivadas
9.
Rev. bras. med. esporte ; 27(spe2): 66-69, Apr.-June 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1280076

RESUMO

ABSTRACT At present, many studies have proved that proper exercise can promote the immune function of human body to a certain extent, but athletes need a lot of high-intensity sports training, and their immune function declines instead of improving. In order to control the decline of immune function of athletes after high-intensity training, this study propose the Zhenqi Fuzheng capsule to achieve this goal. Through experimental comparison, the parameters such as white blood cell content, immunoglobulin number, T lymphocyte, human hemoglobin content and exercise exhaustion time were detected after high-intensity training. The results showed that compared with the control group taking Zhenqi Fuzheng, the weight of those who had taken qifuzhengs capsule did not change, and the content of white blood cells, immunoglobulin, hemoglobin content and exercise time increased to a certain extent. The results showed that Zhenqi Fuzheng could inhibit the decrease of body immune function after high-intensity exercise, then accelerate the recovery of human immune function. This study is expected to enhance the immunity of sports athletes, and reduce athletes' pain after high-intensity training.


RESUMO Atualmente, muitos estudos prova que exercícios adequados podem promover a função imunológica do corpo humano em certa medida, mas os atletas precisam de muito treinamento esportivo de alta intensidade, e sua função imunológica diminui em vez de melhorar. A fim de controlar o declínio da função imunológica dos atletas após treinamento de alta intensidade, este estudo propôs a administração da cápsula Zhenqi Fuzheng para alcançar esse objetivo. Através de comparação experimental, foram detectados parâmetros como o teor de glóbulos brancos, imunoglobulina, linfócitos T, hemoglobina humana e tempo de exaustão do exercício após treinamento de alta intensidade. Os resultados mostraram que, em comparação com o grupo controle que tomou a cápsula Zhenqi Fuzheng, o peso daqueles que tinham tomado a cápsula de qifuzheng não se alterou, e o teor de glóbulos brancos, imunoglobulina, hemoglobina e o tempo de exercício aumentaram em certa medida. Os resultados mostraram que a cápsula Zhenqi Fuzheng poderia inibir a diminuição da função imunológica corporal após exercícios de alta intensidade, e acelerar a recuperação da função imunológica humana. Espera-se que este estudo possa aumentar a imunidade dos atletas e reduzir a dor dos atletas após treinamento alta intensidade para fornecer uma certa referência.


RESUMEN Actualmente, muchos estudios prueban que ejercicios adecuados pueden promover la función inmunológica del cuerpo humano en cierta medida, pero los atletas precisan mucho entrenamiento deportivo de alta intensidad, y su función inmunológica disminuye en vez de mejorar. A fin de controlar la declinación de la función inmunológica de los atletas después del entrenamiento de alta intensidad, este estudio propuso la administración de la cápsula Zhenqi Fuzheng para alcanzar ese objetivo. Por medio de comparación experimental, fueron detectados parámetros como el tenor de glóbulos blancos, inmunoglobulina, linfocitos T, hemoglobina humana y tiempo de agotamiento del ejercicio después de entrenamiento de alta intensidad. Los resultados mostraron que, en comparación con el grupo control que tomó la cápsula Zhenqi Fuzheng, el peso de aquellos que habían tomado la cápsula de qifuzheng no se alteró, y el tenor de glóbulos blancos, inmunoglobulina, hemoglobina y el tiempo de ejercicio aumentaron en cierta medida. Los resultados mostraron que la cápsula Zhenqi Fuzheng podría inhibir la disminución de la función inmunológica corporal después de ejercicios de alta intensidad, y acelerar la recuperación de la función inmunológica humana. Se espera que este estudio pueda aumentar la inmunidad de los atletas y reducir el dolor después de entrenamiento de alta intensidad para proveer una cierta referencia.

10.
Biomolecules ; 11(5)2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068552

RESUMO

Strategies boosting both innate and adaptive immunity have great application prospects in cancer immunotherapy. Antibodies dual blocking the innate checkpoint CD47 and adaptive checkpoint PD-L1 or TIGIT could achieve durable anti-tumor effects. However, a small molecule dual blockade of CD47/SIRPα and TIGIT/PVR pathways has not been investigated. Here, an elevated expression of CD47 and PVR was observed in tumor tissues and cell lines analyzed with the GEO datasets and by flow cytometry, respectively. Compounds approved by the FDA were screened with the software MOE by docking to the potential binding pockets of SIRPα and PVR identified with the corresponding structural analysis. The candidate compounds were screened by blocking and MST binding assays. Azelnidipine was found to dual block CD47/SIRPα and TIGIT/PVR pathways by co-targeting SIRPα and PVR. In vitro, azelnidipine could enhance the macrophage phagocytosis when co-cultured with tumor cells. In vivo, azelnidipine alone or combined with irradiation could significantly inhibit the growth of MC38 tumors. Azelnidipine also significantly inhibits the growth of CT26 tumors, by enhancing the infiltration and function of CD8+ T cell in tumor and systematic immune response in the tumor-draining lymph node and spleen in a CD8+ T cell dependent manner. Our research suggests that the anti-hypertensive drug azelnidipine could be repositioned for cancer immunotherapy.


Assuntos
Ácido Azetidinocarboxílico/análogos & derivados , Di-Hidropiridinas/farmacologia , Reposicionamento de Medicamentos/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Imunoterapia/métodos , Neoplasias/terapia , Animais , Ácido Azetidinocarboxílico/farmacologia , Antígeno CD47/antagonistas & inibidores , Bloqueadores dos Canais de Cálcio/farmacologia , Linhagem Celular Tumoral , Cricetinae , Modelos Animais de Doenças , Humanos , Imunidade Inata , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Terapia de Alvo Molecular , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Receptores Imunológicos/antagonistas & inibidores , Receptores Virais/antagonistas & inibidores , Linfócitos T/efeitos dos fármacos
11.
J Phys Chem Lett ; 12(24): 5649-5659, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34110833

RESUMO

Nonresonant second harmonic generation (SHG) phase and amplitude measurements obtained from the silica-water interface at varying pH values and an ionic strength of 0.5 M point to the existence of a nonlinear susceptibility term, which we call χX(3), that is associated with a 90° phase shift. Including this contribution in a model for the total effective second-order nonlinear susceptibility produces reasonable point estimates for interfacial potentials and second-order nonlinear susceptibilities when χX(3) ≈ 1.5χwater(3). A model without this term and containing only traditional χ(2) and χ(3) terms cannot recapitulate the experimental data. The new model also provides a demonstrated utility for distinguishing apparent differences in the second-order nonlinear susceptibility when the electrolyte is NaCl versus MgSO4, pointing to the possibility of using heterodyne-detected SHG to investigate ion specificity in interfacial processes.

12.
Theranostics ; 11(15): 7308-7321, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34158852

RESUMO

Dendritic cells (DCs) can process the antigens of cancer vaccine and thus stimulate the CD8+ T cells to recognize and kill the tumor cells that express these antigens. However, lack of promising carriers for presenting the antigens to DCs is one of the main barriers to the development of clinically effective cancer vaccines. Another limitation is the risk of inflammatory side effects induced by the adjuvants. It is still unclear how we can develop ideal adjuvant-free DC vaccine carriers without adjuvants. Methods: A 12-mer peptide carrier (CBP-12) with high affinity for Clec9a expressed on DCs was developed using an in silico rational optimization method. The therapeutic effects of the adjuvant-free vaccine comprising CBP-12 and exogenous or endogenous antigenic peptides were investigated in terms of antigen cross-presentation efficacy, specific cytotoxic T lymphocyte response, and antitumor activity. We also explored the mechanism involved in the antitumor effects of the adjuvant-free CBP-12 vaccine. Finally, we assessed the effects of the CBP-12 conjugated peptide vaccine combined with radiotherapy. Results: Here, we developed CBP-12 as a vaccine carrier that enhanced the uptake and cross-presentation of the antigens, thus inducing strong CD8+ T cell responses and antitumor effects in both anti-PD-1-responsive (B16-OVA) and -resistant (B16) models, even in adjuvant-free conditions. CBP-12 bound to and activated Clec9a, thereby stimulating Clec9a+ DC to product IL-21, but not IL-12 by activating of Syk. The antitumor effects of the CBP-12 conjugated peptide vaccines could be blocked by an IL-21 neutralizing antibody. We also observed the synergistic antitumor effects of the CBP-12 conjugated peptide vaccine combined with radiotherapy. Conclusions: CBP-12 could serve as an adjuvant-free peptide vaccine carrier for cancer immunotherapy.


Assuntos
Vacinas Anticâncer , Células Dendríticas/imunologia , Sistemas de Liberação de Medicamentos , Interleucinas/imunologia , Lectinas Tipo C/imunologia , Melanoma Experimental/imunologia , Peptídeos , Receptores Imunológicos/imunologia , Transdução de Sinais/efeitos dos fármacos , Quinase Syk/imunologia , Animais , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/farmacologia , Feminino , Interleucinas/genética , Lectinas Tipo C/genética , Melanoma Experimental/genética , Melanoma Experimental/terapia , Camundongos , Camundongos Knockout , Peptídeos/imunologia , Peptídeos/farmacologia , Receptores Imunológicos/genética , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Quinase Syk/genética , Vacinas de Subunidades/imunologia , Vacinas de Subunidades/farmacologia
13.
J Plant Res ; 134(5): 1105-1120, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33963939

RESUMO

NAC (NAM, ATAF1/2, CUC2) transcription factors play important roles in plant growth, development, and responses to abiotic stress. In this study, we cloned an NAC2 subfamily transcription factor gene (SlNAC7) from the halophyte Suaeda liaotungensis K., and conducted a series of studies to determine the characteristics and functions of this gene. The SlNAC7 coding region contains 1719 base pairs that encode a 573 amino acid long protein. SlNAC7 is expressed in the roots, stems, and leaves of S. liaotungensis, with the highest expression in the leaves. We found that SlNAC7 expression can be induced by drought, salt, cold, and abscisic acid. Transient expression in onion epidermal cells revealed that SlNAC7 is located in both the nucleus and cytoplasm. A transcriptional activation experiment in yeast showed that the transcriptional activation domain of SlNAC7 is located at the C terminus. When SlNAC7 was transformed into Arabidopsis under the control of a CaMV 35S promoter its overexpression was found to enhance the ability of transgenic plants to resist drought, salt, and cold stress. Moreover, these plants showed multiple changes in growth characteristics and physiological and biochemical indices in response to different stresses, as well as the upregulation of numerous stress-related genes. We have thus characterized a new halophyte-derived NAC transcription factor, SlNAC7, which can regulate plant growth and physiological and biochemical changes under adverse conditions by regulating the expression of stress-related genes, thereby enhancing plant stress resistance. SlNAC7 is a promising candidate for breeding new varieties of stress-tolerant crops.


Assuntos
Chenopodiaceae , Regulação da Expressão Gênica de Plantas , Chenopodiaceae/genética , Chenopodiaceae/metabolismo , Resposta ao Choque Frio , Secas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
ACS Appl Mater Interfaces ; 13(21): 24442-24452, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34008947

RESUMO

Most cancers contain abundant tumor-associated macrophages (TAMs). TAMs usually display a tumor-supportive M2-like phenotype; they promote tumor growth and influence lymphocyte infiltration, leading to immunosuppression. These properties have made TAMs an attractive cancer immunotherapy target. One promising immunotherapeutic strategy involves switching the tumor-promoting immune suppressive microenvironment by reprogramming TAMs. However, clinical trials of M2-like macrophage reprogramming have yielded unsatisfactory results due to their low efficacy and nonselective effects. In this article, we describe the development of M2-like macrophage-targeting nanoparticles (PNP@R@M-T) that efficiently and selectively deliver drugs to 58% of M2-like macrophages, over 39% of M1-like macrophages, and 32% of dendritic cells within 24 h in vivo. Compared with the control groups, administration of PNP@R@M-T dramatically reprogrammed the M2-like macrophages (51%), reduced tumor size (82%), and prolonged survival. Our findings indicate that PNP@R@M-T nanoparticles provide an effective and selective reprogramming strategy for macrophage-mediated cancer immunotherapy.


Assuntos
Imunoterapia/métodos , Nanopartículas , Medicina de Precisão , Receptores Toll-Like/agonistas , Macrófagos Associados a Tumor/imunologia , Animais , Humanos , Camundongos
15.
BMC Microbiol ; 21(1): 143, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980153

RESUMO

BACKGROUND: Seed dimorphism has been thought to be a bet-hedging strategy that helps plants survive in the disturbed environment and has been widely studied for its ecological adaptation mechanism. Many studies showed that seed-associated microorganisms play an important role in enhancing plant fitness, but information regarding endophytic bacteria associated with dimorphic seeds is limited. This study explores the influence of seed coat structure and seed phytochemical properties on the community composition and diversity of endophytic bacteria of dimorphic seeds of Suaeda glauca. In this study, we used 16S rRNA high-throughput gene sequencing method to compare the community composition and bacterial diversity between brown and black seeds of Suaeda glauca. RESULTS: A significant difference was observed in seed coat structure and phytochemical properties between brown and black seeds of S. glauca. Total 9 phyla, 13 classes, 31 orders, 53 families, 102 genera were identified in the dimorphic seeds. The dominant phyla were Proteobacteria, Firmicutes, and Actinobacteria. The results showed that seed dimorphism had little impact on the diversity and richness of endophytic bacterial communities but significantly differs in the relative abundance of the bacterial community between brown and black seeds. At the phylum level, Actinobacteria tend to be enriched significantly in brown seeds. At the genus level, Rhodococcus, Ralstonia, Pelomonas and Bradyrhizobium tend to be enriched significantly in brown seeds, while Marinilactibacillus was mainly found in black seeds. Besides, brown seeds harbored a large number of bacteria with plant-growth-promoting traits, whereas black seeds presented bacteria with enzyme activities (i.e., pectinase, cellulolytic and xylanolytic activities). CONCLUSION: The endophytic bacterial community compositions were significantly different between dimorphic seeds of Suaeda glauca, and play an important role in the ecological adaptation of dimorphic seeds by performing different biological function roles. The endophytic bacterial communities of the dimorphic seeds may be influenced mainly by the seed coat structureand partly by the seed phytochemical characteristics. These findings provide valuable information for better understanding of the ecological adaptation strategy of dimorphic seeds in the disturbed environment.

16.
J Ethnopharmacol ; 276: 114168, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-33932511

RESUMO

ETHNOPHARMACOLOGY RELEVANCE: In folkloric medicine of many cultures, one of the medical uses of Valeriana officinalis Linn is to treat heart-related disease. Recently, it was shown that the ethanol extracts from V. officinalis could effectively prevent auricular fibrillation, and 8-hydroxypinoresinol-4-O-ß-D-glucoside (HPG) from the extracts is one of the two active compounds showing antiarrhythmia activities. AIM OF THE STUDY: The human Kv1.5 channel (hKv1.5) has potential antiarrhythmia activities, and this study arms at investigating the current blocking effects of HPG on hKv1.5 channel. MATERIAL AND METHODS: HPG was obtained from V. officinalis extracts, and hKv1.5 channels were expressed in HEK 293 cells. HPG was perfused while recording the current through hKv1.5 channels. Patch-clamp recording techniques were used to study the effects of HPG at various concentrations (10 µM, 30 µM, and 50 µM) on hKv1.5 channels. RESULTS: The present study demonstrated that HPG inhibited hKv1.5 channel current in a concentration-dependent manner; the higher the concentration, the greater is the inhibition at each depolarization potential. During washout, the channels did not full recover indicating that the un-coupling between HPG and hKv1.5 channels is a slow process. CONCLUSION: HPG may be an effective and safe active ingredient for AF having translational potential.

17.
J Agric Food Chem ; 69(22): 6251-6259, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34044543

RESUMO

Proso millet peroxidase (PmPOD) belongs to class III plant peroxidases, which are enzymes typically characterized by their heme coenzymes. PmPOD exhibits not only heme-dependent peroxidase activity but also heme-independent phosphatase activity. Crystal structure analysis and sequence alignment showed that PmPOD contained a phosphatase catalytic loop CXXXXXR in its ß-domain that is similar to the active site of a dual-specific phosphatase. Recombinant truncated proso millet peroxidase (tPmPOD), which contained only a conserved catalytic loop CXXXXXR of phosphatase, was found to exhibit phosphatase activity. Five tPmPOD mutants containing five different mutations in the phosphatase active sites exhibited significantly lower phosphatase activity compared to that of tPmPOD, indicating that the five amino acids play important roles in the phosphatase activity of tPmPOD. Finally, nucleophilic amino acid Cys192 formed a disulfide bond with Cys219 to protect the stability of a sulfhydryl group; thus, it may play a decisive role in the phosphatase activity of PmPOD.


Assuntos
Panicum , Domínio Catalítico , Peroxidase , Peroxidases , Monoéster Fosfórico Hidrolases/genética
18.
Inorg Chem ; 60(10): 7207-7216, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33852289

RESUMO

Here, we present a 1.9 Å resolution crystal structure of Mycoplasma Penetrans ferritin, which reveals that its ferroxidase center is located on the inner surface of ferritin but not buried within the four-helix of each subunit. Such a ferroxidase center exhibits a lower iron oxidation activity as compared to the reported ferritin. More importantly, we found that Fe2+ enters into the center via the rarely reported B-channels rather than the normal 3- or 4-fold channels. All these findings may provide the structural bases to explore the new iron oxidation mechanism adopted by this special ferritin, which is beneficial for understanding the relationship between the structure and function of ferritin.


Assuntos
Ceruloplasmina/metabolismo , Ferritinas/metabolismo , Compostos Ferrosos/metabolismo , Mycoplasma/química , Ceruloplasmina/química , Ferritinas/química , Compostos Ferrosos/química , Simulação de Dinâmica Molecular , Mycoplasma/metabolismo , Oxirredução
19.
Molecules ; 26(9)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925453

RESUMO

Two light-activated NO donors [RuCl(qn)(Lbpy)(NO)]X with 8-hydroxyquinoline (qn) and 2,2'-bipyridine derivatives (Lbpy) as co-ligands were synthesized (Lbpy1 = 4,4'-dicarboxyl-2,2'-dipyridine, X = Cl- and Lbpy2 = 4,4'-dimethoxycarbonyl-2,2'-dipyridine, X = NO3-), and characterized using ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (1H NMR), elemental analysis and electrospray ionization mass spectrometry (ESI-MS) spectra. The [RuCl(qn)(Lbpy2)(NO)]NO3 complex was crystallized and exhibited distorted octahedral geometry, in which the Ru-N(O) bond length was 1.752(6) Å and the Ru-N-O angle was 177.6(6)°. Time-resolved FT-IR and electron paramagnetic resonance (EPR) spectra were used to confirm the photoactivated NO release of the complexes. The binding constant (Kb) of two complexes with human serum albumin (HSA) and DNA were quantitatively evaluated using fluorescence spectroscopy, Ru-Lbpy1 (Kb~106 with HSA and ~104 with DNA) had higher affinity than Ru-Lbpy2. The interactions between the complexes and HSA were investigated using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) and EPR spectra. HSA can be used as a carrier to facilitate the release of NO from the complexes upon photoirradiation. The confocal imaging of photo-induced NO release in living cells was successfully observed with a fluorescent NO probe. Moreover, the photocleavage of pBR322 DNA for the complexes and the effect of different Lbpy substituted groups in the complexes on their reactivity were analyzed.


Assuntos
Complexos de Coordenação/química , Substâncias Macromoleculares/química , Rutênio/química , Complexos de Coordenação/síntese química , Complexos de Coordenação/isolamento & purificação , Complexos de Coordenação/farmacologia , DNA/química , DNA/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Ligantes , Substâncias Macromoleculares/ultraestrutura , Óxido Nítrico/biossíntese , Óxido Nítrico/química , Rutênio/farmacologia , Albumina Sérica Humana/química , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Food Res Int ; 140: 110021, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33648251

RESUMO

Chinese bayberry fruit were treated with hot air (HA) at 48 ℃ for 3 h and then stored at 4 ℃ for 15 d. Changes in fungal communities were analyzed by high-throughput sequencing (HTS), and decay and fruit quality were monitored during storage. The results showed that HA treatment effectively maintains fruit quality and the richness and diversity of fungal communities. Heat treatment inhibited decay development and reduced the growth of fungi in the genera Botryotinia spp., Davidiella spp., Hanseniaspora spp., and Candida spp. Canonical correspondence analysis further revealed that Botryotinia spp. and Davidiella spp. were positively correlated with fruit decay and weight loss. FUNGuild analysis demonstrated that HA-treated bayberries had a lower relative abundance within the plant pathogen guild, but higher relative abundance within the endophyte guild. The results suggest that HA treatment reduces pathogens by favoring the increase of endophytes, providing new insight into the decay development and quality changes during the storage of postharvest Chinese bayberries.


Assuntos
Micobioma , Myrica , China , Conservação de Alimentos , Frutas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...