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1.
Anal Chem ; 96(5): 2253-2263, 2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38277203

RESUMEN

Current study in the heterogeneity and physiological behavior of tumor cells is limited by the fluorescence in situ hybridization technology in terms of probe assembly efficiency, background suppression capability, and target compatibility. In a typically well-designed assay, hybridization probes are constructed in a confined nanostructure to achieve a rapid assembly for efficient signal response, while the excessively high local concentration between different probes inevitably leads to nonspecific background leakage. Inspired by the fabric zipper, we propose a novel confinement reaction pattern in a zipper-confined DNA nanoframe (ZCDN), where two kinds of hairpin probes are independently anchored respective tracks. The metastable states of the dual tracks can well avoid signal leakage caused by the nonspecific probe configuration change. Biomarker-mediated proximity ligation reduces the local distance of dual tracks, kinetically triggering an efficient allosteric chain reaction between the hairpin probes. This method circumvents nonspecific background leakage while maintaining a high efficiency in responding to targets. ZCDN is employed to track different cancer biomarkers located in both the cytoplasm and cytomembrane, of which the expression level and oligomerization behavior can provide crucial information regarding intratumoral heterogeneity. ZCDN exhibits high target response efficiency and strong background suppression capabilities and is compatible with various types of biological targets, thus providing a desirable tool for advanced molecular diagnostics.


Asunto(s)
Técnicas Biosensibles , Nanoestructuras , Hibridación Fluorescente in Situ , ADN/química , Diagnóstico por Imagen , Nanoestructuras/química , Sondas de ADN/genética , Sondas de ADN/química , Técnicas Biosensibles/métodos
2.
Small ; 20(26): e2309087, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38221690

RESUMEN

The severe deterioration of the marine ecosystem significantly negatively impacts the performance of solar-driven steam generation (SSG) and the quality of the obtained freshwater. Herein, a bifunctional Ag/MgFe2O4@SCW reactor with a sandwich structure is designed for efficient SSG and Cr(VI) reduction, which is constructed via in situ deposit Ag nanoparticles (NPs) and MgFe2O4 onto surface carbonized wood (SCW). Owing to the advanced sandwich structure and strong interfacial interactions between each component, an ultra-high evaporation rate of 1.55 kg m-2 h-1 and the efficiency of 88.6% are achieved using Ag/MgFe2O4@SCW under 1 sun. The system exhibits the long-term evaporation performance in the simulated sewage and strong acid/base solutions along with water-harvesting capacity in outdoor solar desalination. The quality of distilled water after desalination of actual seawater and NaCl solutions with different concentrations meets the WHO-recommended drinkable water standards. Furthermore, Ag/MgFe2O4@SCW shows outstanding antibacterial property, self-desalting capacity, as well as reusability and structure stability. Most importantly, the fast carrier separation endows Ag/MgFe2O4@SCW with superior photocatalytic activity and Cr(VI) photoreduction of up to 96.1% after 180 min of illumination. The bifunctional Ag/MgFe2O4@SCW reactor provides an advanced synergistic mechanism for improving SSG and photocatalytic performance, while being promising for solar-powered production of clean water.

3.
Nature ; 546(7658): 436-439, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-28448066

RESUMEN

CRISPR-Cas9 systems are bacterial adaptive immune systems that defend against infection by phages. Through the RNA-guided endonuclease activity of Cas9 they degrade double-stranded DNA with a protospacer adjacent motif (PAM) and sequences complementary to the guide RNA. Recently, two anti-CRISPR proteins (AcrIIA2 and AcrIIA4 from Listeria monocytogenes prophages) were identified, both of which inhibit Streptococcus pyogenes Cas9 (SpyCas9) and L. monocytogenes Cas9 activity in bacteria and human cells. However, the mechanism of AcrIIA2- or AcrIIA4-mediated Cas9 inhibition remains unknown. Here we report a crystal structure of SpyCas9 in complex with a single-guide RNA (sgRNA) and AcrIIA4. Our data show that AcrIIA2 and AcrIIA4 interact with SpyCas9 in a sgRNA-dependent manner. The structure reveals that AcrIIA4 inhibits SpyCas9 activity by structurally mimicking the PAM to occupy the PAM-interacting site in the PAM-interacting domain, thereby blocking recognition of double-stranded DNA substrates by SpyCas9. AcrIIA4 further inhibits the endonuclease activity of SpyCas9 by shielding its RuvC active site. Structural comparison reveals that formation of the AcrIIA4-binding site of SpyCas9 is induced by sgRNA binding. Our study reveals the mechanism of SpyCas9 inhibition by AcrIIA4, providing a structural basis for developing 'off-switch' tools for SpyCas9 to avoid unwanted genome edits within cells and tissues.


Asunto(s)
Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Asociadas a CRISPR/antagonistas & inhibidores , Listeria monocytogenes/enzimología , Listeria monocytogenes/virología , Profagos/genética , Streptococcus pyogenes/enzimología , Proteínas Virales/metabolismo , Sitios de Unión , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/fisiología , Cristalografía por Rayos X , ADN/genética , ADN/metabolismo , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Edición Génica , Listeria monocytogenes/genética , Modelos Moleculares , Unión Proteica , Conformación Proteica , ARN Guía de Kinetoplastida/genética , ARN Guía de Kinetoplastida/metabolismo , Especificidad por Sustrato , Proteínas Virales/genética
4.
Reprod Domest Anim ; 58(8): 1087-1096, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37313775

RESUMEN

Boar sperm are less resistant to drastic changes in the external environment during cryopreservation, mainly because their plasma membranes are rich in unsaturated fatty acids but lack cholesterol and are thus susceptible to lipid peroxidation caused by the attack of reactive oxygen species. This study evaluated the effect of adding phosphocreatine to cryopreservation extenders on boar sperm quality and antioxidant capacity. Different concentrations (0, 5.0, 7.5, 10.0 and 12.5 mmol/L) of phosphocreatine were added to the cryopreservation extender. After thawing, sperm were analysed for morphological parameters, kinetic parameters, acrosome integrity, membrane integrity, mitochondrial activity, DNA integrity and antioxidant enzyme activity. The results showed that 10.0 mmol/L phosphocreatine samples enhanced the boar sperm motility, viability, average path velocity, straight-line velocity, curvilinear velocity and beat cross frequency after cryopreservation and reduced the malformation rate compared to the control group (p < .05). The acrosome integrity, membrane integrity, mitochondrial activity and DNA integrity of boar sperm were higher than those of the control group after adding 10.0 mmol/L phosphocreatine to the cryopreservation extender (p < .05). Extenders containing 10.0 mmol/L phosphocreatine maintained high total antioxidant capacity; elevated the activities of catalase, glutathione peroxidase and superoxide dismutase; reduced malondialdehyde and H2 O2 content (p < .05). Therefore, adding phosphocreatine to the extender is potentially beneficial for boar sperm cryopreservation at an optimal 10.0 mmol/L concentration.


Asunto(s)
Antioxidantes , Preservación de Semen , Masculino , Animales , Porcinos , Antioxidantes/farmacología , Antioxidantes/metabolismo , Fosfocreatina/metabolismo , Fosfocreatina/farmacología , Semen , Motilidad Espermática , Preservación de Semen/veterinaria , Preservación de Semen/métodos , Espermatozoides , Criopreservación/veterinaria , Criopreservación/métodos , ADN , Crioprotectores/farmacología
5.
Nature ; 532(7600): 522-6, 2016 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-27096363

RESUMEN

The CRISPR-Cas systems, as exemplified by CRISPR-Cas9, are RNA-guided adaptive immune systems used by bacteria and archaea to defend against viral infection. The CRISPR-Cpf1 system, a new class 2 CRISPR-Cas system, mediates robust DNA interference in human cells. Although functionally conserved, Cpf1 and Cas9 differ in many aspects including their guide RNAs and substrate specificity. Here we report the 2.38 Å crystal structure of the CRISPR RNA (crRNA)-bound Lachnospiraceae bacterium ND2006 Cpf1 (LbCpf1). LbCpf1 has a triangle-shaped architecture with a large positively charged channel at the centre. Recognized by the oligonucleotide-binding domain of LbCpf1, the crRNA adopts a highly distorted conformation stabilized by extensive intramolecular interactions and the (Mg(H2O)6)(2+) ion. The oligonucleotide-binding domain also harbours a looped-out helical domain that is important for LbCpf1 substrate binding. Binding of crRNA or crRNA lacking the guide sequence induces marked conformational changes but no oligomerization of LbCpf1. Our study reveals the crRNA recognition mechanism and provides insight into crRNA-guided substrate binding of LbCpf1, establishing a framework for engineering LbCpf1 to improve its efficiency and specificity for genome editing.


Asunto(s)
Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Asociadas a CRISPR/química , Proteínas Asociadas a CRISPR/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Firmicutes/enzimología , ARN Bacteriano/química , ARN Bacteriano/metabolismo , Sistemas CRISPR-Cas , Cristalografía por Rayos X , Ingeniería Genética , Modelos Moleculares , Conformación de Ácido Nucleico , Unión Proteica , Estructura Terciaria de Proteína , Estabilidad del ARN , ARN Bacteriano/genética , ARN Guía de Kinetoplastida/química , ARN Guía de Kinetoplastida/genética , ARN Guía de Kinetoplastida/metabolismo , Especificidad por Sustrato
6.
Mikrochim Acta ; 185(2): 131, 2018 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-29594579

RESUMEN

The authors report that cobalt oxyhydroxide (CoOOH) nanoflakes possess intrinsic oxidizing ability to directly oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to form a blue colored product (oxTMB) even in the absence of H2O2 and oxygen. In the presence of ascorbic acid (AA), less of the blue product is formed because AA reduces oxTMB. These findings constitute a new scheme for colorimetric detection of AA. Absorbance, best measured at 652 nm, linearly drops in the 10 nM to 1 µM AA concentration range, and the limit of detection is 5 nM (at an S/N ratio of 3). The reaction is complete within <5 s and highly selective. A strip test has been designed for fast and on-spot visual detection of AA. The method was applied to the direct estimation of AA in the microdialysate of brain, and also in soft drink samples. The strip test is considered to be a promising tool for the rapid screening of AA in brain and commercial samples. Graphic abstract Schematic of the CoOOH-TMB colorimetric system that exhibits a high selectivity for ascorbic acid (AA). A strip test has been designed for fast and on-spot visual detection of AA.

7.
Mediators Inflamm ; 2016: 8048170, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27413257

RESUMEN

Triptolide, a purified component of Tripterygiumwilfordii Hook F, has been shown to have immunosuppressive and anti-inflammatory properties in rheumatoid arthritis (RA). Although triptolide has demonstrated that it could suppress bone destruction in collagen-induced mice, its therapeutic mechanism remains unclear. Many studies have investigated the effect of triptolide on Tregs and Tregs-related cytokine involved in RA. Additionally, previous studies have implied that Tregs inhibit osteoclast differentiation and bone resorption. Thus, in this study we aimed to explore the regulatory mechanism by which triptolide influences the Treg-mediated production of IL-10 and TGF-ß1 to affect osteoclast differentiation and bone resorption. In cocultures system of Tregs and mouse bone marrow macrophages (BMMs), Tregs inhibited the differentiation of osteoclasts and reduced the resorbed areas significantly and the production of both IL-10 and TGF-ß1 was upregulated. When the coculture systems were pretreated with triptolide, they produced higher levels of IL-10 and TGF-ß1. Our data indicate that triptolide enhances the suppressive effects of Tregs on osteoclast differentiation and bone resorption by enhancing the secretion of IL-10 and TGF-ß1. Tregs are most likely involved in the triptolide-mediated regulation of bone metabolism and may provide a potential therapeutic target for the treatment of inflammatory bone destruction.


Asunto(s)
Resorción Ósea/tratamiento farmacológico , Diferenciación Celular/efectos de los fármacos , Diterpenos/uso terapéutico , Interleucina-10/metabolismo , Osteoclastos/citología , Fenantrenos/uso terapéutico , Linfocitos T Reguladores/citología , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Antiinflamatorios/uso terapéutico , Células de la Médula Ósea/citología , Técnicas de Cocultivo , Colágeno/química , Compuestos Epoxi/uso terapéutico , Inmunosupresores/uso terapéutico , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Macrófagos/citología , Masculino , Ratones , Ratones Endogámicos C57BL , Fosfatasa Ácida Tartratorresistente/metabolismo
8.
Adv Mater ; : e2404330, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38723269

RESUMEN

The pursuit of constructing humanoid robots to replicate the anatomical structures and capabilities of human beings has been a long-standing significant undertaking and especially garnered tremendous attention in recent years. However, despite the progress made over recent decades, humanoid robots have predominantly been confined to those rigid metallic structures, which however starkly contrast with the inherent flexibility observed in biological systems. To better innovate this area, the present work systematically explores the value and potential of liquid metals and their derivatives in facilitating a crucial transition towards soft humanoid robots. Through a comprehensive interpretation of bionics, an overview of liquid metals' multifaceted roles as essential components in constructing advanced humanoid robots-functioning as soft actuators, sensors, power sources, logical devices, circuit systems, and even transformable skeletal structures-is presented. It is conceived that the integration of these components with flexible structures, facilitated by the unique properties of liquid metals, can create unexpected versatile functionalities and behaviors to better fulfill human needs. Finally, a revolution in humanoid robots is envisioned, transitioning from metallic frameworks to hybrid soft-rigid structures resembling that of biological tissues. This study is expected to provide fundamental guidance for the coming research, thereby advancing the area.

9.
ACS Appl Mater Interfaces ; 16(3): 4212-4221, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38215272

RESUMEN

Molecules are the smallest units of matter that can exist independently, relatively stable, maintaining their physical and chemical activities. The key factors that dominate the structures and properties of molecules include atomic species, alignment commands, and chemical bonds. Herein, we reported a generalized effect in which liquid metals can directly cut off oxygen-containing groups in molecular matter at room temperature, allowing the remaining groups to recombine to form functional materials. Thus, we propose basic liquid-metal scissors for molecular directional clipping and functional transformations. As a proof of concept, we demonstrate the capabilities of liquid-metal scissors and reveal that the gallium on the surface of liquid metals directly extracts oxygen atoms from H2O or CH3OH molecules to form oxides. After clipping, the remaining hydrogen atoms from the H2O molecules recombine to form H2, while the remaining fragments of CH3OH produce H2, carbon materials, and carboxylates. This finding refreshes our basic understanding of chemistry and should lead to the development of straightforward molecular weaving techniques, which can help to overcome the limitations of molecular substances with single purposes. It also opens a universal route for realizing future innovations in molecular chemical engineering, life sciences, energy and environment research, and biomedicine.

10.
Int J Biol Macromol ; 265(Pt 2): 131118, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38522685

RESUMEN

Conductive hydrogels are widely used as sensors in wearable devices. However, hydrogels cannot endure harsh low-temperature environments. Herein, a new regulatory system based on natural ice-structuring proteins (ISPs) and cellulose nanofibers (CNFs) is introduced into hydrogel network consisting of chemically crosslinked network of copolymerized acrylamide and 2-acrylamide-2-methylpropanesulfonic acid, and physically crosslinked polyvinyl alcohol chains, affording an anti-freezing hydrogel with high conductivity (2.63 S/m). These hydrogels show excellent adhesion behavior to various matrices (including aluminum, glass, pigskin, and plastic). Their mechanical properties are significantly improved with the increase in CNF content (tensile strength of 106.4 kPa, elastic modulus of 133.8 kPa). In addition, ISPs inhibit the growth of ice. This endows the hydrogels with anti-freezing property and allows them to maintain satisfactory mechanical properties, conductivity and sensing properties below zero degrees. Moreover, this hydrogel shows high sensitivity to tensile and compressive deformation (GF = 5.07 at 600-800 % strain). Therefore, it can be utilized to develop strain-type pressure sensors that can be attached directly to human skin for detecting various body motions accurately, reliably, and stably. This study proposes a simple strategy to improve the anti-freezing property of hydrogels, which provides new insights for developing flexible hydrogel electronic devices for application in winter sports.


Asunto(s)
Nanofibras , Humanos , Acrilamida , Caspasa 1 , Celulosa , Conductividad Eléctrica , Hidrogeles
11.
J Biotechnol ; 391: 99-105, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-38880387

RESUMEN

The CRISPR/Cas12a system is emerging as a promising candidate for next-generation diagnostic biosensing platforms, with the discovery of new activation modes greatly expanding its applications. Here, we have identified two novel CRISPR/Cas12a system activation modes: PAM- and toehold-free DNA hairpins, and DNA-RNA hybrid strands. Utilizing a well-established real-time fluorescence method, we have demonstrated a strong correlation between DNA hairpin structures and Cas12a activation. Compared with previously reported activation modes involving single-stranded DNA and PAM-contained double-stranded DNA, the DNA hairpin activation way exhibits similar specificity and generality. Moreover, our findings indicate that increasing the number of RNA bases in DNA-RNA hybrid strands can decelerate the kinetics of Cas12a-triggered trans-cleavage of reporter probes. These newly discovered CRISPR/Cas12a activation ways hold significant potential for the development of high-performance biosensing strategies.


Asunto(s)
Sistemas CRISPR-Cas , ADN , ARN , Sistemas CRISPR-Cas/genética , ARN/genética , ARN/química , ADN/genética , ADN/química , Proteínas Asociadas a CRISPR/genética , Proteínas Asociadas a CRISPR/metabolismo , Técnicas Biosensibles/métodos , ADN de Cadena Simple/genética , ADN de Cadena Simple/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Conformación de Ácido Nucleico , Endodesoxirribonucleasas
12.
Anal Chim Acta ; 1303: 342477, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38609257

RESUMEN

CRISPR/Cas12a-based nucleic acid assays have been increasingly used for molecular diagnostics. However, most current CRISPR/Cas12a-based RNA assays require the conversion of RNA into DNA by preamplification strategies, which increases the complexity of detection. Here, we found certain chimeric DNA-RNA hybrid single strands could activate the trans-cleavage activity of Cas12a, and then discovered the activating effect of split ssDNA and RNA when they are present simultaneously. As proof of concept, split nucleic acid-activated Cas12a (SNA-Cas12a) strategy was developed for direct detection of miR-155. By adding a short ssDNA to the proximal end of the crRNA spacer sequence, we realized the direct detection of RNA targets using Cas12a. With the assistance of ssDNA, we extended the limitation that CRISPR/Cas12a cannot be activated by RNA targets. In addition, by taking advantage of the programmability of crRNA, the length of its binding to DNA and RNA was optimized to achieve the optimal efficiency in activating Cas12a. The SNA-Cas12a method enabled sensitive miR-155 detection at pM level. This method was simple, rapid, and specific. Thus, we proposed a new Cas12a-based RNA detection strategy that expanded the application of CRISPR/Cas12a.


Asunto(s)
MicroARNs , Ácidos Nucleicos , MicroARNs/genética , Sistemas CRISPR-Cas , ARN Guía de Sistemas CRISPR-Cas , ADN de Cadena Simple/genética
13.
Adv Mater ; 36(7): e2309999, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37931919

RESUMEN

The classical Turing morphogenesis often occurs in nonmetallic solution systems due to the sole competition of reaction and diffusion processes. Here, this work conceives that gallium (Ga) based liquid metals (LMs) possess the ability to alloy, diffuse, and react with a range of solid metals (SMs) and thus should display Turing instability leading to a variety of nonequilibrium spatial concentration patterns. This work discloses a general mechanism for obtaining labyrinths, stripes, and spots-like stationary Turing patterns in the LM-SM reaction-diffusion systems (GaX-Y), taking the gallium indium alloy and silver substrate (GaIn-Ag) system as a proof of concept. It is only when Ga atoms diffuse over Y much faster than X while X reacts with Y preferentially, that Turing instability occurs. In such a metallic system, Ga serves as an inhibitor and X as an activator. The dominant factors in tuning the patterning process include temperature and concentration. Intermetallic compounds contained in the Turing patterns and their competitive reactions have also been further clarified. This LM Turing instability mechanism opens many opportunities for constructing microstructure systems utilizing condensed matter to experimentally explore the general morphogenesis process.

14.
Small Methods ; : e2400195, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38699929

RESUMEN

Existing RNA in situ imaging strategies mostly utilize parallel repetitive nucleic acid self-assembly to achieve multiple analysis, with limitations of complicated systems and cumbersome steps. Here, a Cas9 code key system with key probe (KP) encoder and CRISPR/Cas9 signal exporter is developed. This system triggers T-protospacer adjacent motif (T-PAM structural transitions of multiple KP encoders to form coding products with uniform single-guide RNA (sgRNA) target sequences as tandem nodes. Only single sgRNA/Cas9 complex is required to cleave multiple coding products, enabling efficient "many-to-one" tandem signaling, and non-collateral cleavage activity-dependent automatic signaling output through active introduction of mismatched bases. Compared with conventional parallel multiple signaling analysis model, the proposed system greatly simplifies reaction process and enhances detection efficiency. Further, a rapid multiple RNA in situ imaging system is developed by combining the Cas9 code key system with a T-strand displacement amplification (T-SDA) signal amplifier. The constructed system is applied to tumor cells and clinicopathology slices, generating clear multi-mRNA imaging profiles in less than an hour with just one step. Therefore, this work provides reliable technical support for clinical tumor typing and molecular mechanism investigation.

15.
Front Plant Sci ; 14: 1282212, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38046604

RESUMEN

Accurate recognition of pest categories is crucial for effective pest control. Due to issues such as the large variation in pest appearance, low data quality, and complex real-world environments, pest recognition poses challenges in practical applications. At present, many models have made great efforts on the real scene dataset IP102, but the highest recognition accuracy is only 75%. To improve pest recognition in practice, this paper proposes a multi-image fusion recognition method. Considering that farmers have easy access to data, the method performs fusion recognition on multiple images of the same pest instead of the conventional single image. Specifically, the method first uses convolutional neural network (CNN) to extract feature maps from these images. Then, an effective feature localization module (EFLM) captures the feature maps outputted by all blocks of the last convolutional stage of the CNN, marks the regions with large activation values as pest locations, and then integrates and crops them to obtain the localized features. Next, the adaptive filtering fusion module (AFFM) learns gate masks and selection masks for these features to eliminate interference from useless information, and uses the attention mechanism to select beneficial features for fusion. Finally, the classifier categorizes the fused features and the soft voting (SV) module integrates these results to obtain the final pest category. The principle of the model is activation value localization, feature filtering and fusion, and voting integration. The experimental results indicate that the proposed method can train high-performance feature extractors and classifiers, achieving recognition accuracy of 73.9%, 99.8%, and 99.7% on IP102, D0, and ETP, respectively, surpassing most single models. The results also show that thanks to the positive role of each module, the accuracy of multi-image fusion recognition reaches the state-of-the-art level of 96.1%, 100%, and 100% on IP102, D0, and ETP using 5, 2, and 2 images, respectively, which meets the requirements of practical applications. Additionally, we have developed a web application that applies our research findings in practice to assist farmers in reliable pest identification and drive the advancement of smart agriculture.

16.
Nanomaterials (Basel) ; 13(19)2023 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-37836273

RESUMEN

Double bandgap photonic crystals (PCs) exhibit significant potential for applications in various color display-related fields. However, they show low color saturation and inadequate color modulation capabilities. This study presents a viable approach to the fabrication of double bandgap photonic inks diffracting typical secondary colors and other composite colors by simply mixing two photonic nanochains (PNCs) of different primary colors as pigments in an appropriate percentage following the conventional RGB color matching method. In this approach, the PNCs are magnetically responsive and display three primary colors that can be synthesized by combining hydrogen bond-guided and magnetic field (H)-assisted template polymerization. The as-prepared double bandgap photonic inks present high color saturation due to the fixed and narrow full-width at half-maxima of the parent PNCs with a suitable chain length. Furthermore, they can be used to easily produce a flexible double bandgap PC film by embedding the PNCs into a gel, such as polyacrylamide, facilitating fast steady display performance without the requirement of an external magnetic field. This research not only presents the unique advantages of PNCs in constructing multi-bandgap PCs but also establishes the feasibility of utilizing PNCs in practical applications within the fields of anti-counterfeiting and flexible wearable devices.

17.
Theriogenology ; 210: 84-93, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37481978

RESUMEN

Preservation of ovarian tissues is an effective way to ensure genetic diversity of susceptible natural bird populations that are in danger of extinction. We examined whether the addition of the plant phenol resveratrol to vitrification solutions ameliorates the damaging effects of tissue hypoxia and reperfusion injury when the tissues are transplanted. Duck ovary tissues were frozen in the presence of varying concentrations of resveratrol in cryopreservation solutions and then transplanted under the renal capsules of 2-day-old Shelducks. Samples of the transplanted tissues were examined on days 3- and 9- post transplantation for activation of hypoxia-, antioxidant- and apoptosis-related gene expression and apoptosis. Resveratrol significantly increased expression of VEGF, HIF-1α, Nrf2, CAT and Bcl-2 mRNA and decreased BAX and Caspase-3 mRNA and reduced numbers of TUNEL-positive cells after vitrification and heterotopic ovarian transplantation. Resveratrol improved the antioxidant capacity, reduced apoptosis and activated the HIF-1α/VEGF pathway to promote angiogenesis 3- and 9-days following transplantation. These results indicated that the addition of resveratrol to vitrification solutions intended for long-term cryopreservation of ovary tissues improves survival in storage and the grafts following transplantation. This study provides a theoretical basis for the successful transplantation of avian ovarian tissue after vitrification.


Asunto(s)
Patos , Ovario , Femenino , Animales , Ovario/trasplante , Resveratrol/farmacología , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/farmacología , Antioxidantes/farmacología , Criopreservación/veterinaria , Criopreservación/métodos , Vitrificación , Apoptosis
18.
Anim Sci J ; 94(1): e13859, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37537747

RESUMEN

Boar sperm are less resistant to the dramatic environmental changes that occur during in vitro preservation. Spermidine has various physiological functions including the anti-oxidative effect. The main objective of this study was to clarify whether spermidine could protect boar sperm from the attack of reactive oxygen species under cryopreservation treatment. We set the concentrations of spermidine at 0, 2, 4, 6, and 8 mmol/L and evaluated the effects of spermidine on sperm motility, viability, malformation rates, kinetic parameters, membrane integrity, mitochondrial activity, DNA integrity, H2 O2 content, malondialdehyde content, total antioxidant capacity, and antioxidant enzyme activity. Finally, the effects of spermidine on the sperm fertility were assessed by artificial insemination. The results showed that spermidine improved various physiological parameters of sperm in a dose-dependent manner. The quality and antioxidant capacity of sperm cryopreserved with 6 mmol/L spermidine were significantly less reduced (P < 0.05), and the contents of malformation rate, H2 O2 , and malondialdehyde content were significantly decreased (P < 0.05). The significant increase in the number of litters indicated the possibility that spermidine had important practical value in pig reproduction (P < 0.05). Therefore, the addition of appropriate concentrations of spermidine to cryopreservation extenders may effectively improve the quality of boar sperm for in vitro preservation.


Asunto(s)
Preservación de Semen , Espermidina , Porcinos , Masculino , Animales , Espermidina/farmacología , Antioxidantes/farmacología , Motilidad Espermática , Semen , Preservación de Semen/veterinaria , Preservación de Semen/métodos , Espermatozoides/fisiología , Criopreservación/veterinaria , Criopreservación/métodos , Malondialdehído
19.
Front Vet Sci ; 10: 1177873, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37256001

RESUMEN

After artificial insemination, immune cells such as polymorphonuclear neutrophils will be recruited into the genital tract and induce endometrial inflammation, adversely affecting the spermatozoa. This study aimed to analyze the effect of methylprednisolone (MPS) on boar spermatozoa quality of in vitro liquid preservation and chemotaxis and phagocytosis of polymorphonuclear neutrophils toward boar spermatozoa. Various concentrations of MPS were added to the extender and analyzed for their effects on spermatozoa motility, kinetic parameters, abnormality rate, total antioxidant capacity (T-AOC) levels, H2O2 content, mitochondrial membrane potential and acrosome integrity. Testing of MPS on chemotaxis and phagocytosis of polymorphonuclear neutrophils toward spermatozoa induced by lipopolysaccharide (LPS). The results showed that an extender containing 2 × 10-7 mol/mL MPS was the most effective for preserving boar spermatozoa during in vitro liquid preservation at 17°C. It effectively improved spermatozoa motility, kinetic parameters, T-AOC levels, mitochondrial membrane potential and acrosome integrity, reducing the abnormality rate and H2O2 content. Meanwhile, the chemotaxis and phagocytosis of polymorphonuclear neutrophils toward spermatozoa under LPS induction were inhibited in a concentration-dependent manner. In conclusion, MPS has positive implications for improving in vitro liquid preserved boar spermatozoa quality, inhibiting chemotaxis and phagocytosis of polymorphonuclear neutrophils toward spermatozoa.

20.
Theriogenology ; 195: 46-54, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36283226

RESUMEN

This study aimed to investigate the effect of dexamethasone (DEX) on chemotaxis and phagocytic activity of neutrophils for spermatozoa and semen quality of preserved boar semen. The different concentrations of dexamethasone were added to boar semen dilutions to detect its effects on the chemotaxis of neutrophils and phagocytosis of neutrophils and sperm motility sperm malformation rate, plasma membrane integrity, mitochondrial activity, and spermatozoa motility parameters. The study results showed that the experimental groups of DEX significantly inhibited the phagocytosis and chemotaxis of PMNs for spermatozoa. With the increased concentration of DEX, there was an inhibition effect on PMNs activity. In addition, under 17 °C storage conditions, the addition of DEX 1 × 10-6 mol/mL concentration has the best preservation effect on boar semen, which can effectively improve the sperm motility, movement parameters, plasma membrane integrity, mitochondrial activity, T-AOC activity, and significantly reduce the sperm malformation rate and H2O2 content. Therefore, the most suitable concentration of DEX to preserve boar semen at 17 °C is 1 × 10-6 mol/mL. The significant increase of conception rate of sows and litter size of piglets proved that DEX has practical application value. Thus, it is shown that the use of DEX to inhibit uterine inflammation is effective and feasible for sperm damage providing new methods for developing low-dose artificial insemination technology.


Asunto(s)
Preservación de Semen , Semen , Porcinos , Animales , Masculino , Femenino , Semen/fisiología , Análisis de Semen/veterinaria , Preservación de Semen/veterinaria , Preservación de Semen/métodos , Motilidad Espermática , Quimiotaxis , Neutrófilos , Peróxido de Hidrógeno/farmacología , Espermatozoides/fisiología , Dexametasona/farmacología
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