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1.
J Orthop Surg (Hong Kong) ; 32(2): 10225536241249591, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706263

RESUMO

Deep vein thrombosis (DVT) is one of the common complications after joint replacement, which seriously affects the quality of life of patients. We systematically searched nine databases, a total of eleven studies on prediction models to predict DVT after knee/hip arthroplasty were included, eight prediction models for DVT after knee/hip arthroplasty were chosen and compared. The results of network meta-analysis showed the XGBoost model (SUCRA 100.0%), LASSO (SUCRA 84.8%), ANN (SUCRA 72.1%), SVM (SUCRA 53.0%), ensemble model (SUCRA 40.8%), RF (SUCRA 25.6%), LR (SUCRA 21.8%), GBT (SUCRA 1.1%), and best prediction performance is XGB (SUCRA 100%). Results show that the XGBoost model has the best predictive performance. Our study provides suggestions and directions for future research on the DVT prediction model. In the future, well-designed studies are still needed to validate this model.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Metanálise em Rede , Complicações Pós-Operatórias , Trombose Venosa , Humanos , Trombose Venosa/etiologia , Artroplastia do Joelho/efeitos adversos , Artroplastia de Quadril/efeitos adversos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia
2.
Foods ; 13(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38672880

RESUMO

Green leaf volatiles (GLVs) are important in giving grape a fresh and green aroma. But the changes in GLVs during the phenological development of grapevines are not well known. This study analyzed the GLVs and transcription levels of associated biosynthetic genes in six grape species from the Loess Plateau region at five stages of maturation. Thirteen GLVs were detected, showing unique patterns for each grape type at various growth phases. The primary components in six grapes were (E)-2-hexenal, (E)-2-hexen-1-ol, and hexanal. With the exception of Cabernet Franc in 2019, the overall GLV contents of the six types generally increased during growth and development, peaking or stabilizing at harvest. And Sauvignon Blanc, Cabernet Gernischt, and Cabernet Sauvignon exhibited higher total contents among the varieties. PLS-DA analysis revealed 3-hexenal's high VIP scores across two years, underscoring its critical role in grape variety classification. Correlation analysis revealed a strong positive correlation between the levels of hexanal, 1-hexanol, (E)-2-hexen-1-ol, (Z)-3-hexenyl acetate, nonanal, and (E, E)-2,6-nonadienal and the expression of VvHPL and VvAAT genes in the LOX-HPL pathway. Specifically, VvHPL emerges as a potential candidate gene responsible for species-specific differences in GLV compounds. Comprehending the changing patterns in the biosynthesis and accumulation of GLVs offers viticulturists and enologists the opportunity to devise targeted strategies for improving the aromatic profile of grapes and wines.

3.
Food Chem ; 447: 138980, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38564849

RESUMO

Supercooling is a main controllable factor for the fundamental understanding the high-pressure shift freezing (HPSF). In the study, a self-developed device based on the diamond anvil cell (DAC) and confocal Raman microscopy was utilized to realize an in-situ investigation of supercooling behaviour during HPSF of the pure water and sucrose solution. The spectra were used to determine the freezing point which is shown as a spectral phase marker (SD). The hydrogen bond strengths of water and sucrose solution under supercooling states were estimated by peak position and peak area ratio of sub-peaks. The results showed that the OH stretching bands had redshift under supercooling states. Moreover, the addition of sucrose molecules could strengthen the hydrogen bonding strength of water molecules under supercooling states. Thus, the DAC combined with Raman spectroscopy could be considered a novel strategy for a deep understanding of the supercooling behaviour during HPSF.


Assuntos
Água , Congelamento , Água/química , Temperatura de Transição , Microscopia Confocal , Ligação de Hidrogênio
4.
Microorganisms ; 11(11)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-38004652

RESUMO

Tuberculosis (TB) is a chronic infectious disease caused by Mycobacterium tuberculosis (M. tuberculosis). In lymphopenia, T cells are typically characterized by progressive loss and a decrease in their count results. Lymphopenia can hinder immune responses and lead to systemic immunosuppression, which is strongly associated with mortality. Lymphopenia is a significant immunological abnormality in the majority of patients with severe and advanced TB, and its severity is linked to disease outcomes. However, the underlying mechanism remains unclear. Currently, the research on the pathogenesis of lymphopenia during M. tuberculosis infection mainly focuses on how it affects lymphocyte production, survival, or tissue redistribution. This includes impairing hematopoiesis, inhibiting T-cell proliferation, and inducing lymphocyte apoptosis. In this study, we have compiled the latest research on the possible mechanisms that may cause lymphopenia during M. tuberculosis infection. Lymphopenia may have serious consequences in severe TB patients. Additionally, we discuss in detail potential intervention strategies to prevent lymphopenia, which could help understand TB immunopathogenesis and achieve the goal of preventing and treating severe TB.

5.
Fitoterapia ; 162: 105291, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36064154

RESUMO

Oleanolic acid and its derivatives have been widely reported for their antitumor activities. Recently, the introduction of a triphenylphosphonium cation moiety has been described to improve the selectivity and cytotoxicity of pentacyclic triterpenoids by targeting the mitochondria of human cancer cells. In this work, a series of novel mitochondria-targeting oleanolic acid derivatives were synthesized and their antitumor activities assessed. The majority of the compounds are more cytotoxicity to cancer cells than normal cells, especially for 6c with IC50 of 0.81 µM in A549 cells, which showed a slight increase compared to doxorubicin (0.97 µM). Mechanism studies demonstrated that 6c induced apoptosis of A549 cells in a dose-dependent manner, and reactive oxygen species production, mitochondrial membrane potential depolarization, and particularly pro-apoptotic proteins upregulated by western blotting experiment may be responsible for the results. Moreover, 6c arrested the cell cycle at G2/M phase and cell migration in A549 cells. Compound 6c had a comparable or somewhat improved activity to the positive control LY294002 in molecular docking studies and in vitro testing, demonstrating that the apoptosis mechanism may involve inhibition of the PI3K-Akt pathway. These results augur well for the use of 6c as a novel triphenylphosphonium-conjugated anticancer agent.


Assuntos
Antineoplásicos , Ácido Oleanólico , Antineoplásicos/farmacologia , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Proliferação de Células , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Mitocôndrias , Simulação de Acoplamento Molecular , Estrutura Molecular , Ácido Oleanólico/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
Planta ; 254(2): 25, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226949

RESUMO

MAIN CONCLUSION: Some salt-stress responsive DEGs, mainly involved in ion transmembrane transport, hormone regulation, antioxidant system, osmotic regulation, and some miRNA jointly regulated the salt response process in allotriploid Populus cathayana. The molecular mechanism of plant polyploid stress resistance has been a hot topic in biological research. In this study, Populus diploids and first division restitution (FDR) and second division restitution (SDR) triploids were selected as research materials. All materials were treated with 70 mM NaCl solutions for 30 days in the same pot environment. We observed the growth state of triploids and diploids and determined the ratio of potassium and sodium ions, peroxidase (POD) activity, proline content, and ABA and jasmonic acid (JA) hormone content in leaves in the same culture environment with the same concentration of NaCl solution treatment. In addition, RNA-seq technology was used to study the differential expression of mRNA and miRNA. The results showed that triploid Populus grew well and the K+ content and the K+/Na+ ratio in the salt treatment were significantly lower than those in the control. The contents of ABA, JA, POD, and proline were increased compared with contents in diploid under salt stress. The salt-stress responsive DEGs were mainly involved in ion transport, cell homeostasis, the MAPK signaling pathway, peroxisome, citric acid cycle, and other salt response and growth pathways. The transcription factors mainly included NAC, MYB, MYB_related and AP2/ERF. Moreover, the differentially expressed miRNAs involved 32 families, including 743 miRNAs related to predicted target genes, among which 22 miRNAs were significantly correlated with salt-stress response genes and related to the regulation of hormones, ion transport, reactive oxygen species (ROS) and other biological processes. Our results provided insights into the physiological and molecular aspects for further research into the response mechanisms of allotriploid Populus cathayana to salt stress. This study provided valuable information for the salt tolerance mechanism of allopolyploids.


Assuntos
MicroRNAs , Populus , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Populus/genética , Tolerância ao Sal/genética , Transcriptoma
7.
J Colloid Interface Sci ; 588: 725-736, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33309143

RESUMO

Herein, we describe the synthesis of graphene oxide (GO) over a large range of conditions, exploring the effects of reaction temperature, reaction time, oxidant ratio, and sonication time on the chemical and colloidal properties of the product. As a function of reaction parameters, modified from Hummers' method, GO products were characterized and described via a suite of spectroscopic, structural, and morphological techniques, including TEM, UV-vis spectroscopy, XPS, Raman spectroscopy, FTIR, and DLS. Average carbon oxidation state and the yield (upon sonication) were chosen as the two criteria to evaluate synthesized GO materials. It was observed that as reaction temperature increased, GO oxidation state and yield of the sonication step both increased. Further, increasing reaction time and oxidant ratio not only increased the oxidation state, but also had a pronounced effect on the final yield. As synthesized, GO with higher degrees of oxidization exhibited higher negative ζ-potential, slightly smaller hydrodynamic diameter, and higher critical coagulation concentration(s). Data sets collectively demonstrate that carbon oxidation state, functional group ratios, and the aggregation kinetics of GO products can be readily controlled by varying processing time and conditions with expected changes in aqueous behavior(s), including stability/aggregation.

8.
Sci Rep ; 10(1): 19082, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154462

RESUMO

Graphene oxide (GO)-based composite materials have become widely popular in many applications due to the attractive properties of GO, such as high strength and high electrical conductivity at the nanoscale. Most current GO composites use organic polymer as the matrix material and thus, their synthesis suffers from the use of organic solvents or surfactants, which raise environmental and energy-consumption concerns. Inspired by mussel foot proteins (Mfp) secreted by the saltwater mussel, Mytilus galloprovincialis and by recent advances in microbial protein production, we developed an aqueous-based green synthesis strategy for preparing GO/Mfp film composites. These GO/Mfp films display high tensile strength (134-158 MPa), stretchability (~ 26% elongation), and high toughness (20-24 MJ/m3), beyond the capabilities of many existing GO composites. Renewable production of Mfp proteins and the facile fabrication process described provides a new avenue for composite material synthesis, while the unique combination of mechanical properties of GO/Mfp films will be attractive for a range of applications.


Assuntos
Materiais Biocompatíveis/química , Grafite/química , Proteínas/química , Animais , Módulo de Elasticidade , Condutividade Elétrica , Química Verde , Teste de Materiais , Fenômenos Mecânicos , Microscopia Eletrônica de Varredura , Mytilus/química , Nanocompostos/química , Nanocompostos/ultraestrutura , Proteínas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Propriedades de Superfície , Resistência à Tração
9.
Appl Opt ; 59(23): 6932-6938, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32788783

RESUMO

A simple reservoir computing (RC) system based on a solitary semiconductor laser under an electrical message injection is proposed, and the performances of the RC are numerically investigated. Considering the lack of memory capacity (MC) in such a system, some auxiliary methods are introduced to enhance the MC and optimize the performances for processing complex tasks. In the pre-existing method, the input information is the current input data combined with some past input data in a weighted sum in the input layer (named as M-input). Another auxiliary method (named as M-output) is proposed to introduce the output layer for optimizing the performances of the RC system. The simulated results demonstrate that the MC of the system can be improved after adopting the auxiliary methods, and the effectiveness under adopting the M-input integrated with the M-output (named as M-both) is the most significant. Furthermore, we analyze the system performances for processing the Santa Fe time series prediction task and the nonlinear channel equalization (NCE) task after adopting the above three auxiliary methods. Results show that the M-input is the most suitable for the prediction task while the M-both is the most appropriate for the NCE task.

10.
ACS Appl Mater Interfaces ; 11(1): 924-929, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30540180

RESUMO

In this work, we have developed and characterized flux-enhanced graphene oxide laminate (GOL) membranes by increasing interlayer (layer-to-layer) spacing using multibranched polyethylenimine (PEI) polymers with varied molecular weights and by controlling the graphene oxide (GO) oxidation extent. For these assemblies, water flux was demonstrated to increase by as much as ca. 30-fold compared to GO only laminate controls. PEI-embedded GOL membranes also had better methyl orange (MO) rejection performance than GO laminate controls due to the dilution effects (i.e., water is transported through the assembly much faster than MO). Further, boron removal is demonstrated via functionalized PEI with d-glucono-1,5-lactone, containing a high density of boron chelating groups, which can also be recycled/recovered with high efficiency.

11.
Environ Sci Technol ; 51(23): 13723-13732, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29132211

RESUMO

The fluvial export of dissolved black carbon (DBC) is a major land-ocean flux in the global black carbon cycle, affecting the size of refractory carbon pool in the oceans. The aggregation behavior of DBC is a significant determinant of its transport and vertical mass flux. In this study, the aggregation kinetics and interaction energy of DBC leached from biochar were investigated. DBC was mainly stabilized by hydration force and underwent structural compacting in divalent cation solutions. Na+ and Mg2+ had limited impact on the colloidal stability of DBC due to the strong hydration of these cations. Ca2+ and Ba2+ readily destabilized DBC by forming inner-sphere complexes, reducing its hydrophilicity. Consistently, charge reversal of DBC was observed with high concentrations of Ca2+ and Ba2+. Simulated sunlight exposure led to photo-oxidation of DBC, increasing its colloidal stability. DBC behaved nonconservatively in laboratory mixing experiments using estuary water samples due to aggregation/sedimentation; while model aquatic humic acid behaved conservatively. Our results infer that there is a vertical mass flux of DBC and possible fractionation from the dissolved organic matter pool in the fluvial and estuarine systems, which have been overlooked in efforts to determine global carbon budgets and associated climate change implications.


Assuntos
Substâncias Húmicas , Fuligem , Carbono , Peso Molecular , Oceanos e Mares
12.
Molecules ; 21(2)2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26861264

RESUMO

Multidrug resistance (MDR) is a prime reason for numerous failed oncotherapy approaches. In the present study, we investigated whether Alisol F 24 acetate (ALI) could reverse the MDR of MCF-7/DOX cells, a multidrug-resistant human breast cancer cell line. We found that ALI was a potent P-glycoprotein (P-gp) inhibitor, in the Caco-2-monolayer cell model. ALI showed a significant and concentration-dependent cytotoxic effect on MCF-7/DOX cells in combination with doxorubicin by increasing intracellular accumulation and inducing nuclear migration of doxorubicin. However, ALI had no such effect on MCF-7 cells. In addition, ALI also promoted doxorubicin-induced early apoptosis of MCF-7/DOX cells in a time-dependent manner. These results suggest that ALI can enhance chemosensitivity of doxorubicin and reinforce its anti-cancer effect by increasing its uptake, especially inducing its nuclear accumulation in MCF-7/DOX cells. Therefore, ALI could be developed as a potential MDR-reversing agent in cancer chemotherapy in further study.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Doxorrubicina/farmacologia , Triterpenos/farmacologia , Antineoplásicos/metabolismo , Células CACO-2 , Núcleo Celular/metabolismo , Sobrevivência Celular , Digoxina/farmacologia , Doxorrubicina/metabolismo , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7
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