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1.
Small ; 19(28): e2300734, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36967553

RESUMO

Lithium metal batteries are promising to become a new generation of energy storage batteries. However, the growth of Li dendrites and the volume expansion of the anode are serious constraints to their commercial implementation. Herein, a controllable strategy is proposed to construct an ultrathin 3D hierarchical host of honeycomb copper micromesh loaded with lithiophilic copper oxide nanowires (CMMC). The uniquely designed 3D hierarchical arrayed skeletons demonstrate a surface-preferred and spatial-selective effect to homogenize local current density and relieve the volume expansion, effectively suppressing the dendrite growth. Employing the constructed CMMC current collector in a half-cell, >400 cycles with 99% coulombic efficiency at 0.5 mA cm-2 is performed. The symmetric battery cycles stably for >2000 h, and the full battery delivers a capacity of 166.6 mAh g-1 . This facile and controllable approach provides an effective strategy for constructing high-performance lithium metal batteries.

2.
Cell Biochem Funct ; 41(8): 1442-1450, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37933894

RESUMO

Phenolic compounds present in plants have demonstrated several biological properties such as antioxidant, antitumor, cardioprotective, and antiproliferative. On the other hand, doxorubicin, a chemotherapeutic widely used to treat breast cancer, usually exhibits chronic cardiotoxicity associated with oxidative stress. Therefore, we aimed to study the effects of phenolic compound-enriched extract (PCEE) with doxorubicin in breast cancer. To achieve this, after an SPE-C18 -column purification process of crude extracts obtained from pecan nutshells (Carya illinoinensis), the resulting PCEE was used to evaluate the cytotoxicity and antioxidant properties against the human breast cancer cell line MDA-MB-231 and the normal-hamster ovary cell line CHO-K1. PCEE was selectively cytotoxic against both cell lines, with an IC50 value (≈26.34 mg/L) for MDA-MB-231 lower than that obtained for CHO-K1 (≈55.63 mg/L). As a cytotoxic mechanism, PCEE inhibited cell growth by G2/M cell cycle arrest in MDA-MB-231 cells. Simultaneously, the study of the antioxidant activity showed that PCEE had a cytoprotective effect, evidenced by reduced ROS production in cells with oxidative stress caused by doxorubicin. The results highlight PCEE as a potential antitumor agent, thus revaluing it as an agro-industrial residue.


Assuntos
Antineoplásicos , Neoplasias da Mama , Carya , Humanos , Feminino , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Neoplasias da Mama/patologia , Antioxidantes/farmacologia , Antioxidantes/química , Células MDA-MB-231 , Linhagem Celular Tumoral , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antineoplásicos/farmacologia , Proliferação de Células , Fenóis/farmacologia , Doxorrubicina/farmacologia , Apoptose
3.
Anal Bioanal Chem ; 412(26): 7349-7356, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32783126

RESUMO

The application of the dye-labeled fluorescence method in a ligand-RNA interaction assay is a complex and costly process prone to steric hindrance. Fluorescent nanomaterials offer an attractive alternative due to their simple, low-cost synthesis and effective screening properties. Here, CdTe@ZIF-8 core-shell nanocomposites were used as fluorescence signal transducer in the ligand-TAR RNA interaction assay. Different experimental strategies were developed based on the size-selective nature of the CdTe@ZIF-8 nanocomposites. When ligands can quench fluorescence, two assays of fluorescence recovery with TAR RNA and Tat peptide competitive displacement are carried out successively, which can not only distinguish ligands binding to TAR RNA but also screen potential Tat protein antagonists. When ligands cannot quench fluorescence, the mitoxantrone-TAR RNA complex is used in the competitive displacement assay. Ligands that displaced mitoxantrone from the mitoxantrone-TAR RNA complex signaled the interaction with TAR RNA. Eight ligands, including known and unknown TAR RNA-binding ligands, were tested via the above strategies. The results showed that this method was effective at distinguishing the known RNA-binding partner and screening the Tat antagonist from the test ligands. This simple and effective strategy is expected to be suitable for actual drug screening. Graphical abstract.


Assuntos
Nanocompostos/química , RNA/química , Sítios de Ligação , Fluorescência , Ligantes
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123947, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38280244

RESUMO

The selective enhancement mechanism in surface-enhanced Raman scattering (SERS) is demonstrated. Two different types of single nanoparticles (Au nanosphere and Au nanorod) were used to investigate the role of the localized surface plasmon resonance (LSPR) in SERS spectra by using the two-trace two-dimensional (2T2D) correlation spectroscopy. The SERS intensities of three probe molecules, 4-mercaptobenzoic acid (4-MBA), 4-aminothiophenol (4-ATP), and 4-bromobenzenethiol (4-BBT), respectively, were enhanced but slightly different when adsorbed on Au nanospheres and Au nanorods. 2T2D correlation SERS spectra clearly showed that even with the same shape of Au nanoparticles, the main factors influencing the SERS enhancement can vary depending on the specific type of SERS tags used. Such subtle difference could not be clearly identified by the conventional spectral analysis. This result sheds light on potential applications of 2T2D correlation spectroscopy. For 4-MBA molecules, the a1 and b2 modes are mainly affected by the Au nanospheres and Au nanorods. For 4-ATP molecules, the a1 and b2 modes related to C-S stretching combined with C-C stretching band are mainly affected by Au nanorods and Au nanospheres. For 4-BBT molecules, the a1 and b2 modes of C-C (aromatic ring) stretching band are mainly affected by Au nanorods and Au nanospheres. This study offers valuable insights into the relationship between nanoparticle shape and SERS enhancement.

5.
Sci Total Environ ; 879: 163043, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-36963678

RESUMO

Organophosphorus pesticides (OPs) are widely used in agricultural production, but the resulting pollution and drug resistance have sparked widespread concern. Therefore, this paper built a model to design OP substitute molecules with high functionality and environmental friendliness, as well as conducted various human health and ecological environment evaluations, synthetic accessibility screening, and easy detection screening. The functionality of the two OP substitute molecules, DIM-100 and DIM-164, increased by 22.79 % and 22.18 %, respectively, and the environmental friendliness increased by 18.07 % and 24.02 %, respectively. The human health risk and ecological, environmental risks were significantly reduced. Both molecules are easy to synthesize, and their detection sensitivity is 9.85 % and 11.24 % higher than that of the target molecule, respectively. Furthermore, significant changes in the distribution of electrons and holes near the C8 and S1 atoms of the OP substitute molecule resulted in easier breakage of the C8-S1 bond, enhancing its photodegradation ability. The charge transfer ability between the atoms of the molecule (as increasing the electron-withdrawing group led to an increase in charge of the P atom) and the volume of the cholinesterase active pocket both affect the functionality of the DIM substitute molecule. That is, the volume of the cholinesterase active pocket of the bee is smaller than that of the brown planthopper and is more affected by the volume of the OP molecule. Furthermore, the mutual verification analysis of the bidirectional selectivity effect of OP substitute molecules between the BayesianRidge model and the 3D-QS(A2 + ∀3)R model reveals that the overall charge transfer degree of DIM substitute molecules is the main reason for the increase in the bidirectional selectivity effect.


Assuntos
Praguicidas , Humanos , Animais , Praguicidas/análise , Compostos Organofosforados/análise , Agricultura , Colinesterases , Poluição Ambiental/análise
6.
Adv Sci (Weinh) ; 9(18): e2201702, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35470590

RESUMO

Organic ferroelectrics, as a type of crystalline compound, are generally solution processing. However, for most crystalline compounds, the changing of solvent would not influence the crystalline phase, let alone their physical performance. Here, the solvent selective effect occurs in the iodinated adamantanone ferroelectrics. By changing the solvent with different polarities, the ferroelectric crystals can be induced in two different phases, which is unprecedented to the knowledge. More strikingly, this solvent-induced transformation could realize the physical performance optimization in the orthorhombic phase (orth-I-OA, obtained from ethanol) with a stronger second harmonic generation (SHG) response, greater piezoelectric coefficient d33 of 5 pC N-1 , and larger spontaneous polarization (Ps ) of 3.43 µC cm-2 than those of monoclinic one (mono-I-OA, obtained from ethyl acetate). Such an intriguing phenomenon might be closely related to solvent polarity. Based on the quantitative and qualitative analyses, the similar interaction energies of these two phases suggest that their transformation could be easily realized via changing the solvent. This work provides new insights into the chemical design and performance optimization of organic ferroelectrics.

7.
Comput Struct Biotechnol J ; 20: 2807-2814, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35685365

RESUMO

Synergistic effects between drugs are rare and highly context-dependent and patient-specific. Hence, there is a need to develop novel approaches to stratify patients for optimal therapy regimens, especially in the context of personalized design of combinatorial treatments. Computational methods enable systematic in-silico screening of combination effects, and can thereby prioritize most potent combinations for further testing, among the massive number of potential combinations. To help researchers to choose a prediction method that best fits for various real-world applications, we carried out a systematic literature review of 117 computational methods developed to date for drug combination prediction, and classified the methods in terms of their combination prediction tasks and input data requirements. Most current methods focus on prediction or classification of combination synergy, and only a few methods consider the efficacy and potential toxicity of the combinations, which are the key determinants of therapeutic success of drug treatments. Furthermore, there is a need to further develop methods that enable dose-specific predictions of combination effects across multiple doses, which is important for clinical translation of the predictions, as well as model-based identification of biomarkers predictive of heterogeneous drug combination responses. Even if most of the computational methods reviewed focus on anticancer applications, many of the modelling approaches are also applicable to antiviral and other diseases or indications.

8.
Eur J Pharmacol ; 904: 174182, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34004212

RESUMO

Restraint stress (RS) is an unavoidable stress model that triggers activation of the autonomic nervous system, endocrine activity, and behavioral changes in rodents. Furthermore, RS induces secretion of oxytocin into the bloodstream, indicating a possible physiological role in the stress response in this model. The presence of oxytocin receptors in vessels and heart favors this possible idea. However, the role of oxytocin secreted in RS and effects on the cardiovascular system are still unclear. The aim of this study was to analyze the influence of oxytocin on cardiovascular effects during RS sessions. Rats were subjected to pharmacological (blockade of either oxytocin, vasopressin, or muscarinic receptors) or surgical (hypophysectomy or sinoaortic denervation) approaches to study the functional role of oxytocin and its receptor during RS. Plasma levels of oxytocin and vasopressin were measured after RS. RS increased arterial pressure, heart rate, and plasma oxytocin content, but not vasopressin. Treatment with atosiban (a Gi biased agonist) inhibited restraint-evoked tachycardia without affecting blood pressure. However, this effect was no longer observed after sinoaortic denervation, homatropine (M2 muscarinic antagonist) treatment or hypophysectomy, indicating that parasympathetic activation mediated by oxytocin secreted to the periphery is responsible for blocking the increase in tachycardic responses observed in the atosiban-treated group. Corroborating this, L-368,899 (oxytocin antagonist) treatment showed an opposite effect to atosiban, increasing tachycardic responses to restraint. Thus, this provides evidence that oxytocin secreted to the periphery attenuates tachycardic responses evoked by restraint via increased parasympathetic activity, promoting cardioprotection by reducing the stress-evoked heart rate increase.


Assuntos
Ocitocina/metabolismo , Restrição Física/fisiologia , Estresse Psicológico/fisiopatologia , Animais , Antagonistas dos Receptores de Hormônios Antidiuréticos/farmacologia , Barorreflexo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Masculino , Agonistas Muscarínicos/farmacologia , Ocitocina/sangue , Parassimpatolíticos/farmacologia , Ratos Wistar , Receptor Muscarínico M2/antagonistas & inibidores , Receptores de Vasopressinas/fisiologia , Estresse Psicológico/sangue , Taquicardia/fisiopatologia , Tropanos/farmacologia , Vasopressinas/sangue , Vasotocina/análogos & derivados , Vasotocina/farmacologia
9.
Microorganisms ; 9(5)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068582

RESUMO

Minerals provide physical niches and supply nutrients or serve as electron donors/acceptors for microorganism survival and growth, and thus minerals and microbes co-evolved. Yet, little is known about how sediment minerals impact microbial community assembly in hot springs and to what extent mineralogical composition influences microbial community composition and diversity. Here the influences of minerals on thermophiles in Tengchong hot springs were revealed by network analysis of field samples, as well as in-situ microcosm experiments with minerals. A molecular ecological network was constructed based on high throughput sequencing data of 16S rRNA gene, with a combination of water geochemistry and sedimentary mineralogical compositions. Six modules were identified and this highly modular network structure represents the microbial preference to different abiotic factors, consequently resulting in niche partitioning in sedimentary communities in hot springs. Diverse mineralogical compositions generated special niches for microbial species. Subsequently, the in-situ microcosm experiments with four minerals (aragonite, albite, K-feldspar, and quartz) and spring water were conducted in a silicate-hosted alkaline spring (i.e., Gmq) and a carbonate-hosted neutral hot spring (i.e., Gxs) for 70 days. Different microbial preferences were observed among different mineral types (carbonate versus silicate). Aragonite microcosms in Gmq spring enriched archaeal genera Sulfophobococcus and Aeropyrum within the order Desulfurococcales by comparison with both in-situ water and silicate microcosms. Sulfophobococcus was also accumulated in Gxs aragonite microcosms, but the contribution to overall dissimilarity is much lower than that in Gmq spring. Besides, Caldimicrobium was a bacterial genus enriched in Gxs aragonite microcosms, in contrast to in-situ water and silicate microcosms, whereas Candidatus Kryptobacter and Thermus were more abundant in silicate microcosms. The differences in microbial accumulations among different mineral types in the same spring implied that mineral chemistry may exert extra deterministic selective pressure in drawing certain species from the bulk water communities, in addition to stochastic absorption on mineral surface. Taken together, our results highlight the special niche partitioning determined by mineralogical compositions and further confirm that minerals could be used as "fishing bait" to enrich certain rare microbial species.

10.
Environ Int ; 137: 105554, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32062436

RESUMO

Antibiotics in aquatic environments at high concentrations and sub-inhibitory concentrations potentially select for the evolution of antibiotic resistant genes (ARGs), posing a potential risk to aquatic ecological safety. Our knowledge of the temporal and successive dynamics of ARGs and bacterial community under the selective pressure of antibiotics in natural water-sediment system was limited. This study used a 120-d operating hydrodynamic mesocosm to explore the temporal dynamics of ARGs in water-sediment systems, and the main selective mechanisms following the attenuation and transport of 14 commonly used antibiotics. Under the selective pressures by antibiotics, ARGs propagated transiently, and persisted after antibiotic removal; the bacterial community structures likewise changed. Mantel test and network analysis indicated that ARGs significantly correlated with the bacterial community in the water and surface sediments. Structural equation model (SEM) further revealed that the evolution of ARGs was mainly due to the direct effect of the change in bacterial community and horizontal gene transfer (HGT) via the class 1 integron-integrase gene (intI1), but antibiotics indirectly influenced ARG profiles. The migration of ARGs in deep layer sediments was not related to the bacterial community and intI1, but may be explained by antibiotic selective effects and ARG transformation.


Assuntos
Antibacterianos , Resistência Microbiana a Medicamentos , Genes Bacterianos , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Fatores de Tempo , Água
11.
Integr Med Res ; 1(1): 36-40, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28664045

RESUMO

BACKGROUND: The objectives of this study were to compare the efficacy of acupuncture among different types and to evaluate point-selective pain relief effects between selected adjacent or distant points in participants with temporomandibular joint disorders (TMDs). METHODS: Forty-two participants were randomly allocated to three groups: an adjacent point selection group (Trt, n = 14), a distant point selection group (Con1, n = 14), or a combination group (Con2, n = 14). All three groups received a total of six acupuncture sessions (twice a week for 3 weeks), the outcomes being assessed pain intensity using a 10-cm visual analogue scale, and the palpation index of the muscle and temporomandibular joint every week of treatment and 4 weeks after the end of treatment. RESULTS: The pain intensity was reduced in the Trt (34%), Con1 (31%), and Con2 (36%) groups after 3 weeks compared with each group's baseline, with no significant difference among the three groups (p = 0.5867). Similarly, the palpation index was decreased by 52% (Trt), 62% (Con1), and 50% (Con2) after 3 weeks of treatment, but no significant differences between groups were shown (p = 0.3289). CONCLUSION: Our results suggest that point-selective effects among adjacent, distal, or a combination of acupoints are hardly associated with pain intensity or palpation index in participants with TMDs. Larger sample size trials are required to overcome the shortcomings of the study.

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