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1.
Nature ; 629(8012): 586-591, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38720080

RESUMEN

Light-emitting diodes (LEDs) based on perovskite quantum dots (QDs) have produced external quantum efficiencies (EQEs) of more than 25% with narrowband emission1,2, but these LEDs have limited operating lifetimes. We posit that poor long-range ordering in perovskite QD films-variations in dot size, surface ligand density and dot-to-dot stacking-inhibits carrier injection, resulting in inferior operating stability because of the large bias required to produce emission in these LEDs. Here we report a chemical treatment to improve the long-range order of perovskite QD films: the diffraction intensity from the repeating QD units increases three-fold compared with that of controls. We achieve this using a synergistic dual-ligand approach: an iodide-rich agent (aniline hydroiodide) for anion exchange and a chemically reactive agent (bromotrimethylsilane) that produces a strong acid that in situ dissolves smaller QDs to regulate size and more effectively removes less conductive ligands to enable compact, uniform and defect-free films. These films exhibit high conductivity (4 × 10-4 S m-1), which is 2.5-fold higher than that of the control, and represents the highest conductivity recorded so far among perovskite QDs. The high conductivity ensures efficient charge transportation, enabling red perovskite QD-LEDs that generate a luminance of 1,000 cd m-2 at a record-low voltage of 2.8 V. The EQE at this luminance is more than 20%. Furthermore, the stability of the operating device is 100 times better than previous red perovskite LEDs at EQEs of more than 20%.

2.
Nano Lett ; 24(9): 2765-2772, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38393855

RESUMEN

Alloying lanthanide ions (Yb3+) into perovskite quantum dots (Yb3+:CsPb(Cl1-xBrx)3) is an effective method to achieve efficient near-infrared (NIR) luminescence (>950 nm). Increasing the Yb3+ alloying ratio in the perovskite matrix enhances the luminescence intensity of Yb3+ emission at 990 nm. However, high Yb3+ alloying (>15%) results in vacancy-induced inferior material stability. In this work, we developed a polarity-mediated antisolvent manipulation strategy to resolve the incompatibility between a high Yb3+ alloying ratio and inferior stability of Yb3+:CsPb(Cl1-xBrx)3. Precise control of solution polarity enables increased uniformity of the perovskite matrix with fewer trap densities. Employing this strategy, we obtain Yb3+:CsPb(Cl1-xBrx)3 with the highest Yb3+ alloying ratio of 30.2% and a 2-fold higher electroluminescence intensity at 990 nm. We lever the engineered Yb3+:CsPb(Cl1-xBrx)3 to fabricate NIR-LEDs, achieving a peak external quantum efficiency (EQE) of 8.5% at 990 nm: this represents the highest among perovskite NIR-LEDs with an emission wavelength above 950 nm.

3.
J Cell Physiol ; 239(1): 166-179, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37991438

RESUMEN

Abnormal function and fibrosis of endometrium caused by cows' endometritis pose difficult implantation of embryos and uterine cavity adhesions. 17ß-Estradiol (E2) serves as the most effective aromatized estrogen, and its synthetase and receptors have been detected in the endometrium. Studies have demonstrated the positive role of estrogen in combating pathological fibrosis in diverse diseases. However, it is still unknown whether E2 regulates endometrium fibrosis in bovine endometritis. Herein, we evaluated the expression patterns of transforming growth factor-ß1 (TGF-ß1), epithelial-mesenchymal transformation (EMT)-related proteins (α-SMA, vimentin N-cadherin and E-cadherin), cytochrome P450 19A1 (CYP19A1), and G protein-coupled estrogen receptor (GPER) in bovine healthy endometrium and Inflammatory endometrium. Our data showed that the inflamed endometrium presented low CYP19A1 and GPER expression, and significantly higher EMT process versus the normal tissue. Moreover, we established a TGF-ß1-induced fibrosis model in BEND cells, and found that E2 inhibited the EMT process of BEND cells in a dose-dependent manner. The anti-fibrotic effect of E2 was blocked by the GPER inhibitor G15, but not the estrogen nuclear receptors (ERs) inhibitor ICI182780. Moreover, the GPER agonist G1 inhibited fibrosis and Smad2/3 phosphorylation but increased the expression of TGFBR3 in BEND cells. Transfection with TGFBR3 small interfering RNA blocked the effect of G1 on fibrosis of BEND cells and upregulated the expression of P-Smad2/3. Our in vivo data also showed that E2 and G1 affected uterus fibrosis in mice endometritis model caused by LPS, which was associated with the inhibition of TGFBR3/Smad2/3 signaling. In conclusion, our data implied that E2 alleviates the fibrosis of TGF-ß1-induced BEND cells, which is associated with the GPER mediation of TGFBR3/Smad2/3 signaling.


Asunto(s)
Endometritis , Estradiol , Proteoglicanos , Receptores de Factores de Crecimiento Transformadores beta , Factor de Crecimiento Transformador beta1 , Animales , Bovinos , Femenino , Ratones , Endometritis/metabolismo , Endometrio/metabolismo , Células Epiteliales/metabolismo , Transición Epitelial-Mesenquimal , Estradiol/farmacología , Estrógenos/metabolismo , Fibrosis , Receptores Acoplados a Proteínas G/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Proteínas Smad/metabolismo
4.
Small ; : e2404087, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39031097

RESUMEN

Membrane separation stands as an environmentally friendly, high permeance and selectivity, low energy demand process that deserves scientific investigation and industrialization. To address intensive demand, seeking appropriate membrane materials to surpass trade-off between permeability and selectivity and improve stability is on the schedule. 2D materials offer transformational opportunities and a revolutionary platform for researching membrane separation process. Especially, the atomically thin graphene with controllable porosity and structure, as well as unique properties, is widely considered as a candidate for membrane materials aiming to provide extreme stability, exponentially large selectivity combined with high permeability. Currently, it has shown promising opportunities to develop separation membranes to tackle bottlenecks of traditional membranes, and it has been of great interest for tremendously versatile applications such as separation, energy harvesting, and sensing. In this review, starting from transport mechanisms of separation, the material selection bank is narrowed down to nanoporous graphene. The study presents an enlightening overview of very recent developments in the preparation of atomically thin nanoporous graphene and correlates surface properties of such 2D nanoporous materials to their performance in critical separation applications. Finally, challenges related to modulation and manufacturing as well as potential avenues for performance improvements are also pointed out.

5.
Acc Chem Res ; 56(7): 740-751, 2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-36920352

RESUMEN

ConspectusSelf-assembly bridges nanoscale and microscale colloidal particles into macroscale functional materials. In particular, self-assembly processes occurring at the liquid/liquid or solid/liquid/air interfaces hold great promise in constructing large-scale two- or three-dimensional (2D or 3D) architectures. Interaction of colloidal particles in the assemblies leads to emergent collective properties not found in individual building blocks, offering a much larger parameter space to tune the material properties. Interfacial self-assembly methods are rapid, cost-effective, scalable, and compatible with existing fabrication technologies, thus promoting widespread interest in a broad range of research fields.Surface chemistry of nanoparticles plays a predominant role in driving the self-assembly of nanoparticles at water/oil interfaces. Amphiphilic nanoparticles coated with mixed polymer brushes or mussel-inspired polydopamine were demonstrated to self-assemble into closely packed thin films, enabling diverse applications from electrochemical sensors and catalysis to surface-enhanced optical properties. Interfacial assemblies of amphiphilic gold nanoparticles were integrated with graphene paper to obtain flexible electrodes in a modular approach. The robust, biocompatible electrodes with exceptional electrocatalytic activities showed excellent sensitivity and reproducibility in biosensing. Recyclable catalysts were prepared by transferring monolayer assemblies of polydopamine-coated nanocatalysts to both hydrophilic and hydrophobic substrates. The immobilized catalysts were easily recovered and recycled without loss of catalytic activity. Plasmonic nanoparticles were self-assembled into a plasmonic substrate for surface-enhanced Raman scattering, metal-enhanced fluorescence, and modulated fluorescence resonance energy transfer (FRET). Strong Raman enhancement was accomplished by rationally directing the Raman probes to the electromagnetic hotspots. Optimal enhancement of fluorescence and FRET was realized by precisely controlling the spacing between the metal surface and the fluorophores and tuning the surface plasmon resonance wavelength of the self-assembled substrate to match the optical properties of the fluorescent dye.At liquid/solid interfaces, infiltration-assisted (IFAST) colloidal self-assembly introduces liquid infiltration in the substrate as a new factor to control the degree of order of the colloidal assemblies. The strong infiltration flow leads to the formation of amorphous colloidal arrays that display noniridescent structural colors. This method is compatible with a broad range of colloidal particle inks, and any solid substrate that is permeable to dispersing liquids but particle-excluding is suitable for IFAST colloidal assembly. Therefore, the IFAST technology offers rapid, scalable fabrication of structural color patterns of diverse colloidal particles with full-spectrum coverage and unprecedented flexibility. Metal-organic framework particles with either spherical or polyhedral morphology were used as ink particles in the Mayer rod coating on wettability patterned photopapers, leading to amorphous photonic structures with vapor-responsive colors. Anticounterfeiting labels have also been developed based on the complex optical features encoded in the photonic structures.Interfacial colloidal self-assembly at the water/oil interface and IFAST assembly at the solid/liquid/air interface have proven to be versatile fabrication platforms to produce functional materials with well-defined properties for diverse applications. These platform technologies are promising in the manufacturing of value-added functional materials.

6.
Neurochem Res ; 49(8): 2131-2147, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38822984

RESUMEN

BACKGROUND: Sepsis-associated encephalopathy (SAE) develops in 30-70% of hospitalized patients with sepsis. In intensive care units (ICUs), propofol is often administered to ensure an appropriate level of sedation in mechanically ventilated patients. Ferroptosis is a newly identified mode of cellular death characterized by the peroxidation of membrane lipids and excessive iron. This study was conducted to explore the interplay between propofol, sepsis, and ferroptosis. METHODS: An acute systemic inflammatory model was constructed via the intraperitoneal administration of lipopolysaccharide (LPS). Nissl and Fluoro-Jade C (FJC) staining were employed to display neuronal damage and degeneration. Western blotting and immunofluorescence (IF) staining of Bax and Bcl-2 were used to confirm the neural apoptosis. QPCR of cytokines and DHE staining were used to indicate neuroinflammation. To validate ferroptosis, we assessed the content of malondialdehyde (MDA), GSH, and tissue iron, accompanied by transcription level of CHAC1, PTGS2 and GPX4. Additionally, we examined the content of acyl-CoA synthetase long-chain family member 4 (ACSL4), xCT (SLC7A11, solute carrier family 7 member 11), and glutathione peroxidase 4 (GPX4). The IF staining of Iba1-labeled microglia and GFAP-marked astrocytes were used to measure the gliosis. Erastin was pre-pretreated to confirm the anti-ferroptotic capability of propofol. ML385 was preconditioned to explore the role of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in propofol-repressed ferroptosis. RESULTS: Propofol dose-dependently inhibited the decrease of Nissl-positive neurons and the increase of FJC-stained neurons in septic hippocampus and cortex. Neural cytokines, oxidative stress, apoptosis and gliosis were reduced by propofol. Propofol repressed the level of MDA, iron, CHAC1, PTGS2, ACLS4 and restored the content of GSH, GPX4, xCT, Nrf2 and HO-1, thus inhibiting sepsis-induced ferroptosis. All protections from propofol could be reversed by eratsin and ML385 pretreatment. CONCLUSION: Propofol protected against sepsis-induced brain damage, neuroinflammation, neuronal apoptosis and gliosis through the activation of the Nrf2/HO-1 axis to combat ferroptosis.


Asunto(s)
Ferroptosis , Factor 2 Relacionado con NF-E2 , Propofol , Ferroptosis/efectos de los fármacos , Ferroptosis/fisiología , Propofol/farmacología , Propofol/uso terapéutico , Factor 2 Relacionado con NF-E2/metabolismo , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Sepsis/metabolismo , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Lipopolisacáridos , Encefalopatía Asociada a la Sepsis/metabolismo , Encefalopatía Asociada a la Sepsis/tratamiento farmacológico , Encefalopatía Asociada a la Sepsis/prevención & control , Hemo-Oxigenasa 1/metabolismo , Hemo Oxigenasa (Desciclizante)/metabolismo , Proteínas de la Membrana/metabolismo , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/tratamiento farmacológico , Coenzima A Ligasas , Sistema de Transporte de Aminoácidos y+
7.
Int Wound J ; 21(1): e14614, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38272824

RESUMEN

We conducted this study aimed to explore the effect of operating room nursing intervention on wound infection in patients undergoing ovarian cysts surgery. A computer system was used to search PubMed, Web of Science, EMBASE, Cochrane Library, Wanfang, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure databases, from database inception to October 2023, for randomised controlled trials (RCTs) on the application of operating room nursing intervention to ovarian cyst surgery. Literature that met the requirements was independently screened by two researchers, and data were extracted and assessed for literature quality. RevMan 5.4 software was applied for data analysis. Fifteen RCTs involving 1187 patients were finally included. The analyses revealed that, compared with routine nursing, the implementation of operating room nursing intervention had a significant advantage in reducing the incidence of wound infections (1.17% vs. 5.44%, odds ratio [OR]: 0.30, 95% confidence interval [CI]: 0.15-0.58, p = 0.0004) and postoperative complications (6.34% vs. 25.17%, OR: 0.20, 95%CI: 0.13-0.29, p < 0.00001), as well as being able to shorten the operative time (standardised mean difference [SMD]: -3.93, 95%CI: -5.67 to -2.20, p < 0.00001), hospital length of stay (SMD: -2.54, 95%CI: -3.19 to -1.89, p < 0.00001) and gastrointestinal recovery time (SMD: -1.61, 95%CI: -2.24 to -0.98, p < 0.00001) in patients undergoing ovarian cysts surgery. This study confirmed by meta-analysis that the operating room nursing intervention can significantly reduce the incidence of wound infection and complications, shorten the operative time, gastrointestinal recovery time, and hospital length of stay after ovarian cyst surgery.


Asunto(s)
Enfermería de Quirófano , Quistes Ováricos , Infección de Heridas , Femenino , Humanos , Complicaciones Posoperatorias/prevención & control , Enfermería Perioperatoria , Quistes Ováricos/cirugía
8.
Langmuir ; 39(5): 1709-1718, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-36692408

RESUMEN

Phenolic-compound-based functional coatings that allow for flexible modulation of chemical and surface properties have found widespread uses in a diverse range of biomedical applications from antibiofouling and antioxidation to bioimaging, therapeutics, and controlled drug delivery. It is imperative to understand the formation mechanism of phenolic coatings to fully meet the needs of their emerging applications in controlling the surface properties of biomaterials and medical devices. In this Perspective, we highlight the versatile chemical and self-assembly approaches to generate phenolic coatings with tailored surface properties and reactivities and also discuss how the surface properties and chemical reactivities impart functional materials for translational research.


Asunto(s)
Materiales Biocompatibles , Fenoles , Propiedades de Superficie , Antioxidantes , Sistemas de Liberación de Medicamentos
9.
Gen Comp Endocrinol ; 333: 114182, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36455642

RESUMEN

Melatonin potentially regulates the female animal reproductive function, but its regulatory mechanism in the apoptosis of sheep endometrial epithelial cells (SEECs) remains to be elucidated. In the present study, immunofluorescence staining, western blotting, and quantitative real-time polymerase chain reaction were performed to detect the distribution of melatonin receptors (MT1 and MT2) in the uterus of sheep and the effect of melatonin via the receptor and non-receptor pathways on the apoptosis of SEECs in vitro. The results showed that melatonin inhibits the apoptosis of SEECs to varying degrees to regulate the expression of estrogen receptors (ERs) and progesterone receptors (PGR) via its interaction with MT1 and MT2. In addition, the ER antagonist partially relieved the inhibitory effect of melatonin on the apoptosis of SEECs, while the PGR antagonist did not. Thus, melatonin mediates endometrial epithelial apoptosis through the MT receptors and also by regulating estrogen function. This study provides evidence of the regulatory mechanism of melatonin on the physiological function of the sheep uterus.


Asunto(s)
Melatonina , Receptor de Melatonina MT1 , Femenino , Animales , Ovinos , Receptor de Melatonina MT1/genética , Receptor de Melatonina MT1/análisis , Receptor de Melatonina MT1/metabolismo , Receptor de Melatonina MT2/análisis , Receptor de Melatonina MT2/metabolismo , Melatonina/farmacología , Melatonina/metabolismo , Células Epiteliales/metabolismo , Apoptosis
10.
Sensors (Basel) ; 23(20)2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37896516

RESUMEN

The measurement of seed cotton moisture regain (MR) during harvesting operations is an open and challenging problem. In this study, a new method for resistive sensing of seed cotton MR measurement based on pressure compensation is proposed. First, an experimental platform was designed. After that, the change of cotton bale parameters during the cotton picker packaging process was simulated through the experimental platform, and the correlations among the compression volume, compression density, contact pressure, and conductivity of seed cotton were analyzed. Then, support vector regression (SVR), random forest (RF), and a backpropagation neural network (BPNN) were employed to build seed cotton MR prediction models. Finally, the performance of the method was evaluated through the experimental platform test. The results showed that there was a weak correlation between contact pressure and compression volume, while there was a significant correlation (p < 0.01) between contact pressure and compression density. Moreover, the nonlinear mathematical models exhibited better fitting performance than the linear mathematical models in describing the relationships among compression density, contact pressure, and conductivity. The comparative analysis results of the three MR prediction models showed that the BPNN algorithm had the highest prediction accuracy, with a coefficient of determination (R2) of 0.986 and a root mean square error (RMSE) of 0.204%. The mean RMSE and mean coefficient of variation (CV) of the performance evaluation test results were 0.20% and 2.22%, respectively. Therefore, the method proposed in this study is reliable. In addition, the study will provide a technical reference for the accurate and rapid measurement of seed cotton MR during harvesting operations.

11.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-36674716

RESUMEN

The demand for economic benefits has led to an increase in the proportion of high-concentrate (HC) feed in the ruminant diet, resulting in an increased incidence of subacute ruminal acidosis (SARA). During SARA, a high concentration of lipopolysaccharide (LPS) translocated in the rumen induces a systemic inflammatory response. Inflammatory diseases, such as endometritis and mastitis, are often associated with SARA; however, in sheep, the mechanism of the effect of SARA on the endometrium has rarely been reported. Therefore, the aim of this study was to investigate, for the first time, the influence of LPS translocation on endometrial tight junctions (TJs) during SARA in sheep. The results showed that LPS and TNFα levels in the ruminal fluid, serum, and endometrial tissue supernatant during SARA increased, transcription levels of TLR4, NFκB, and TNFα in the endometrium increased, the protein expression level of claudin-1 in the endometrium increased, and the protein expression level of occludin decreased. 17ß-estradiol (E2) inhibits claudin-1 protein expression and promotes occludin expression, and progesterone (P4) promotes claudin-1 protein expression and inhibits occludin protein expression. E2 and P4 regulate claudin-1 and occludin protein expression through their receptor pathways. Here, we found that LPS hindered the regulatory effect of E2 and P4 on endometrial TJs by inhibiting their receptor expression. The results of this study indicate that HC feeding can cause SARA-induced LPS translocation in sheep, increase susceptibility to systemic inflammation, induce the endometrial inflammatory response, and cause endometrial epithelial TJ damage directly and/or by obstructing E2 and P4 function. LPS translocation caused by SARA has also been suggested to induce an endometrial inflammatory response, resulting in endometrial epithelial barrier damage and physiological dysfunction, which seriously affects ruminant production. Therefore, this study provides new evidence that SARA is a potential factor that induces systemic inflammation in ruminants. It provides theoretical support for research on the prevention of endometritis in ruminants.


Asunto(s)
Acidosis , Endometritis , Femenino , Humanos , Ovinos , Animales , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Rumen , Endometritis/veterinaria , Endometritis/metabolismo , Lipopolisacáridos/metabolismo , Claudina-1/metabolismo , Ocludina/metabolismo , Dieta/veterinaria , Inflamación/metabolismo , Endometrio/metabolismo , Acidosis/metabolismo , Concentración de Iones de Hidrógeno
12.
Angew Chem Int Ed Engl ; 62(46): e202311089, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37770413

RESUMEN

Resurfacing perovskite nanocrystals (NCs) with tight-binding and conductive ligands to resolve the dynamic ligands-surface interaction is the fundamental issue for their applications in perovskite light-emitting diodes (PeLEDs). Although various types of surface ligands have been proposed, these ligands either exhibit weak Lewis acid/base interactions or need high polar solvents for dissolution and passivation, resulting in a compromise in the efficiency and stability of PeLEDs. Herein, we report a chemically reactive agent (Iodotrimethylsilane, TMIS) to address the trade-off among conductivity, solubility and passivation using all-inorganic CsPbI3 NCs. The liquid TMIS ensures good solubility in non-polar solvents and reacts with oleate ligands and produces in situ HI for surface etching and passivation, enabling strong-binding ligands on the NCs surface. We report, as a result, red PeLEDs with an external quantum efficiency (EQE) of ≈23 %, which is 11.2-fold higher than the control, and is among the highest CsPbI3 PeLEDs. We further demonstrate the universality of this ligand strategy in the pure bromide system (CsPbBr3 ), and report EQE of ≈20 % at 640, 652, and 664 nm. This represents the first demonstration of a chemically reactive ligand strategy that applies to different systems and works effectively in red PeLEDs spanning emission from pure-red to deep-red.

13.
Anal Chem ; 94(10): 4463-4473, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35199513

RESUMEN

We present a highly efficient multichannel microfluidic electrochemical sensor integrated with an electroactive nanocarbon microelectrode for sensitive and selective detection of multiple biomarkers in different biological samples. Our results have shown that ionic liquid-assisted wet spinning followed by tailored growth of metal-organic frameworks and pyrolysis treatment led to structural and molecular engineering of mechanically robust all-carbon microfibers for excellent electrochemical activities. The flexible bottlebrush-like nanocarbon microelectrode features a "stem" of freestanding N, B-codoped graphene fiber and high-density "bristles" of Co, N-codoped carbon nanotube arrays, leading to promoted electrocatalytic mechanism that has been substantiated by density functional theory calculations. The structural characteristics, high catalytic activities, and favorable biocompatibility of the bottlebrush nanocarbon electrodes provide opportunities for multichannel, microfluidic detection of redox-active biomolecules, including hydrogen sulfide (H2S), dopamine (DA), uric acid (UA), and ascorbic acid (AA), and have been applied to on-chip monitoring of H2S and DA released from live cancer cells or neuroblastoma cells and DA, UA, and AA in trace amounts of body fluids such as sweat, finger blood, tears, saliva, and urine, which is of great significance for clinical diagnosis and prognosis in point-of-care testing.


Asunto(s)
Técnicas Electroquímicas , Grafito , Ácido Ascórbico/química , Dopamina , Técnicas Electroquímicas/métodos , Electrodos , Grafito/química , Microelectrodos , Microfluídica , Ácido Úrico
14.
Macromol Rapid Commun ; 43(10): e2100812, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35394089

RESUMEN

Cationic polymers are under intense research to achieve prominent antimicrobial activity. However, the cellular and in vivo toxicity caused by nonspecific electrostatic interaction has become a major challenge for their practical applications. Here, the development of a "caging" strategy based on the use of a block copolymer consisting of a stealth block and an anionic block that undergoes degradation in presence of enzymes secreted by selective bacterial pathogens of interest is reported. The results have shown that antimicrobial cationic polymer brushes-coated gold nanorods (AuNRs) can be caged by the block polymer of poly(ethylene glycol) and anionic, lipase-degradable block of ε-caprolactone and methacrylic acid copolymer to afford neutrally charged surfaces. The caged AuNRs are activated by lipase released by bacteria of interest to endow an excellent bactericidal effect but show minimal binding and toxicity against mammalian cells and nonspecific bacteria that do not produce lipase. In this design, AuNRs play multifunctional roles as the scaffolds for polymer brushes, photothermal transducers, and imaging probes for traceable delivery of the activation and delivery of bactericidal cationic polymer brushes. The caging strategy opens new opportunities for the safe delivery of antimicrobial materials for the treatment of bacterial infections.


Asunto(s)
Nanoestructuras , Polímeros , Animales , Antibacterianos/química , Antibacterianos/farmacología , Bacterias , Cationes , Lipasa , Mamíferos , Nanoestructuras/química , Polietilenglicoles/química , Polímeros/química , Polímeros/farmacología
15.
Reprod Domest Anim ; 57(11): 1406-1417, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35881670

RESUMEN

During maturation, spermatozoa acquire motility and fertilizing capacity as they transit through the epididymis. Melatonin is a lipophilic hormone with multiple functions in regulating the fertility. Previous studies have shown that melatonin affected the capacitation or maturation of sperm in the epididymis. The aim of this study was to investigate the effects of melatonin on epididymal caput epithelial cells in sheep. In the study, we used iTRAQ labelling coupled with LC-MS/MS for quantitative identification of differentially expressed proteins in melatonin-treated sheep epididymal caput epithelial cells. We identified 69 differentially expressed protein; 41 were upregulated and 28 were downregulated in samples from sheep in melatonin treated. We validated the differential expression of a subset of these proteins using qPCR and Western blot. Gene ontology annotation identified that the differentially expressed proteins function in cellular processes and metabolic processes. Notably, five of the differentially expressed proteins as SOD1, COL1A1, PRM1, NQO2, and FN1 are involved in sperm migration and sperm maturation. KEGG enrichment analysis demonstrated significant enrichment in several cardiac-related pathways, such as "PI3K-Akt signaling pathway", "AGE-RAGE signaling pathway in diabetic complications", "ECM-receptor interaction", and "Ribosome". Our results suggest that candidate biomarker (SOD1, COL1A1, PRM1, NQO2, and FN1) discovery can aid in understanding sperm development and maturation in sheep. These results provide insights into the potential mechanisms of melatonin regulation of sperm maturation in epididymal caput epithelial cells.


Asunto(s)
Epidídimo , Melatonina , Masculino , Ovinos , Animales , Epidídimo/metabolismo , Melatonina/farmacología , Melatonina/metabolismo , Proteómica , Cromatografía Liquida/veterinaria , Fosfatidilinositol 3-Quinasas/metabolismo , Superóxido Dismutasa-1/metabolismo , Semen , Espectrometría de Masas en Tándem/veterinaria , Maduración del Esperma/fisiología , Espermatozoides/fisiología , Proteínas/metabolismo , Células Epiteliales
16.
Reprod Domest Anim ; 57(12): 1602-1614, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36018566

RESUMEN

Melatonin has known anti-inflammatory effects. Yet, how melatonin protects sheep endometrial epithelial cells from inflammation remains unknown. In this study, we investigated the melatonin synthetase AANAT and HIOMT and melatonin membrane receptors MT1 and MT2 distribution in sheep uterus. Using lipopolysaccharide (LPS)-stimulated sheep endometrial epithelial cells as an in vitro inflammation model. The results showed that melatonin attenuated the expression of inflammatory factors in a concentration-response manner. Melatonin also inhibited the LPS-stimulated phosphorylation of ERK1/2, JNK and NF-κB p65. This attenuation was partially blocked by luzindole (a non-specific MT1 and MT2 inhibitor) or 4P-PDOT (specific MT2 inhibitor). In addition, the above inhibition of melatonin was abolished by the PI3K/AKT pathway inhibitor LY294002. It was concluded that melatonin had an inhibitory effect on LPS-induced endometrial epithelial cell inflammation in sheep, which was mediated by the activation of the PI3K/AKT pathway via melatonin receptors.


Asunto(s)
Melatonina , Enfermedades de las Ovejas , Femenino , Ovinos , Animales , Melatonina/metabolismo , Lipopolisacáridos/toxicidad , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores de Melatonina/metabolismo , Células Epiteliales/metabolismo , Inflamación/inducido químicamente , Inflamación/prevención & control , Inflamación/veterinaria
17.
Reprod Domest Anim ; 57(10): 1244-1254, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35775862

RESUMEN

Melatonin (MEL) is involved in homeostasis of the epididymis lumen environment. Dihydrotestosterone (DHT) partakes in the development of gonads and organs in male animals. However, whether MEL secretion, the expression of its receptors, MT1 and MT2, and sheep epididymal epithelial cell apoptosis is regulated by DHT remains unclear. In this study, we used immunohistochemical staining to detect the distribution patterns of DHT synthetases [5α-reductase (5α-red)] and its androgen receptor (AR) in sheep epididymides. 5α-red1, 5α-red2 and AR were positively expressed in sperm, epididymal epithelial cells, and the smooth muscle cells of the caput, corpus and cauda regions of the epididymis. DHT concentration and the expression levels of 5α-red and AR in the caput, corpus and cauda regions were measured by enzyme-linked immunosorbent assay, liquid chromatography-mass spectrometry, real-time quantitative polymerase chain reaction and western blot analysis. DHT concentration in the caput was significantly higher than those in corpus and cauda, probably because of the high expression of 5α-red2 in the caput and secretion and transport of DHT by the testicles. DHT inhibited MEL secretion, the expression of its membrane receptors and MEL synthetases in cultured sheep epididymal epithelial cells in vitro. In addition, the Bax/Bcl-2 ratio, ACT CASP3 and caspase-3 mRNA expression were also decreased. The decreasing effect was partially reversed after flutamide treatment. Therefore, DHT regulates sheep epididymal function by influencing MEL expression and apoptosis-related factors. This study provides basic data for further research on the reproductive physiology of male animals.


Asunto(s)
Epidídimo , Melatonina , Animales , Apoptosis , Caspasa 3/metabolismo , Dihidrotestosterona/metabolismo , Dihidrotestosterona/farmacología , Epidídimo/metabolismo , Flutamida/metabolismo , Flutamida/farmacología , Ligasas/metabolismo , Ligasas/farmacología , Masculino , Melatonina/metabolismo , Melatonina/farmacología , ARN Mensajero/metabolismo , Receptores Androgénicos/genética , Receptores de Melatonina/metabolismo , Semen/química , Ovinos , Proteína X Asociada a bcl-2/metabolismo
18.
Nano Lett ; 21(6): 2625-2633, 2021 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-33683889

RESUMEN

Silver sulfide (Ag2S) has gained widespread attention in second near-infrared (950-1700 nm, NIR-II) window imaging because of its high fluorescence quantum yield and low toxicity. However, its "always on" fluorescence shows inapplicability for targeted molecule-activated biomedical applications. Herein, we first developed a novel silver/silver sulfide Janus nanoparticle (Ag/Ag2S JNP) for specific activatable fluorescence imaging in the NIR-II window. Inner-particle electron compensation from Ag to Ag2S upon laser irradiation endowed JNPs an "off" state of fluorescence, whereas the oxidization of Ag incubated with H2O2, decreasing the electron-transfer effect and illuminating the NIR-II fluorescence of the Ag2S part. In contrast, the absorption of Ag/Ag2S JNPs slightly decreased in an H2O2-dependent manner, showing an activated photoacoustic imaging mechanism. The Ag/Ag2S JNPs were used for noninvasive location and diagnosis of diseases in vivo, such as for liver injury and cancer, with high sensitivity and accuracy.

19.
J Cell Mol Med ; 25(11): 4974-4987, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33932098

RESUMEN

As a variety of free radical scavenger, edaravone has shown its potential in producing antioxidant, anti-inflammatory and neuroprotective effects in various disease models. However, the underlying mechanism behind the neuroprotective effects of edaravone remained unclear. This study is aimed at determining the effects of edaravone on neuroprotection and anti-inflammatory through a propofol-induced neural injury rat model. Firstly, an observation was made of apoptosis and neuroinflammation in the hippocampus of developing under the influence of propofol. It was found out that propofol could produce inflammatory effects in the hippocampus by enhancing the astrogliosis (GFAP) activation and elevating the level of neuronal nitric oxide synthase (nNOS), pro-inflammatory cytokines interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α). Meanwhile, the increase of apoptosis cells and the decrease of neurons (NeuN) were speculated to aggravate neural injury. Furthermore, it was demonstrated that edaravone intervention can reverse the neural apoptosis and inflammation. Additionally, the intraperitoneal injection of edaravone, the intraperitoneal injection of the brain-derived neurotrophic factor (BDNF)-mimicking small compound (7,8 dihydroxyflavone) and the intracranial injection of the exogenous BDNF were all respectively effective in alleviating the propofol-induced neural apoptosis and inflammation in the hippocampus. It was also found out that edaravone-activated downstream signalling through tyrosine kinase receptor B (TrkB) receptors in astrocyte, microglia and neuron. However, the neural injury of propofol had no impact on long-term learning and memory, except causing a short-term neurotoxicity. In conclusion, edaravone could alleviate the propofol-induced neural injury in developing rats through BDNF/TrkB pathway.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Edaravona/farmacología , Inflamación/tratamiento farmacológico , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Propofol/toxicidad , Receptor trkB/metabolismo , Animales , Animales Recién Nacidos , Factor Neurotrófico Derivado del Encéfalo/genética , Células Cultivadas , Hipnóticos y Sedantes/toxicidad , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Masculino , Neuronas/metabolismo , Neuronas/patología , Ratas , Ratas Sprague-Dawley , Receptor trkB/genética
20.
Small ; 17(2): e2006357, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33325629

RESUMEN

Nanoparticles have been widely used in detection and killing of bacteria; however, targeting bacteria is still challenging. Delicate design of nanoparticles is required for simultaneous targeting, detection, and therapeutic functions. Here the use of Au/MnFe2 O4 (Au/MFO) Janus nanoparticles to target Gram-positive bacteria via metabolic labeling is reported and realize integrated self-reporting and thermal killing of bacteria. In these nanoparticles, the Au component is functionalized with tetrazine to target trans-cyclooctene group anchored on bacterial cell wall by metabolic incorporation of d-amino acids, and the MFO part exhibits peroxidase activity, enabling self-reporting of bacteria before treatment. The spatial separation of targeting and reporting functions avoids the deterioration of catalytic activity after surface modification. Also important is that MFO facilitates magnetic separation and magnetic heating, leading to easy enrichment and magnetic thermal therapy of labeled bacteria. This method demonstrates that metabolic labeling with d-amino acids is a promising strategy to specifically target and kill Gram-positive bacteria.


Asunto(s)
Nanopartículas de Magnetita , Nanopartículas Multifuncionales , Nanopartículas , Bacterias Grampositivas , Magnetismo
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