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1.
Phys Chem Chem Phys ; 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39188237

RESUMEN

CO2 hydrogenation into valuable chemical compounds can effectively address the issues of greenhouse gas emissions and energy scarcity. The activation and dissociation processes of CO2 are crucial for its reduction reactions, but the effects of *H adatoms on the C-O cleavage are still confusing. This study investigates the H-assisted CO2 dissociation pathways on the PdnPt(4-n)/In2O3 (n = 0-4) catalysts via DFT calculation. Initially, the adsorption properties of *H2, *COOH, and *HCOO species are calculated. Then, two H-assisted CO2 dissociation channels, i.e., *CO2 + *H → *COOH → *CO + *OH and *CO2 + *H → *HCOO → *CHO + *O, are studied. Results show that Pt and Pd promote the CO2 hydrogenation and C-O bond cleavage reactions, respectively. In comparison to CO2 direct dissociation, the COOH-mediated and HCOO-mediated channels facilitate and impede the C-O bond cleavage, respectively. Overall, the Pd3Pt/In2O3 constituent is suggested for the H-assisted CO2 dissociation reaction. The electronic effects of the PdnPt(4-n) bimetals adjust the stabilities of the intermediates and barriers of the elementary steps, and the interactions between PdnPt(4-n) and In2O3 provide extra sites for the adsorbates and reaction steps. This study reveals the effects of *H on the C-O bond dissociation processes and provides useful insight into designing PdPt/In2O3 catalysts for CO2 hydrogenation reactions.

2.
Int Immunopharmacol ; 140: 112818, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39083924

RESUMEN

Cell death caused by severe Staphylococcus aureus (S. aureus) infection is a fatal threat to humans and animals. However, whether ferroptosis, an iron-dependent form of cell death, is involved in S. aureus-induced cell death and its role in S. aureus-induced diseases are unclear. Using a mouse mastitis model and mammary epithelial cells (MMECs), we investigated the role of ferroptosis in the pathogenesis of S. aureus infection. The results revealed that S. aureus-induced ferroptosis in vivo and in vitro as demonstrated by dose-dependent increases in cell death; the level of malondialdehyde (MDA), the final product of lipid peroxidation; and dose-dependent decrease the production of the antioxidant glutathione (GSH). Treatment with typical inhibitors of ferroptosis, including ferrostatin-1 (Fer-1) and deferiprone (DFO), significantly inhibited S. aureus-induced death in MMECs. Mechanistically, treatment with S. aureus activated the protein kinase RNA-like ER kinase (PERK)-eukaryotic initiation factor 2, α subunit (eIF2α)-activating transcription factor 4 (ATF4)-C/EBP homologous protein (CHOP) pathway, which subsequently upregulated autophagy and promoted S. aureus-induced ferroptosis. The activation of autophagy degraded ferritin, resulting in iron dysregulation and ferroptosis. In addition, we found that excessive reactive oxygen species (ROS) production induced ferroptosis and activated endoplasmic reticulum (ER) stress, manifesting as elevated p-PERK-p-eIF2α-ATF4-CHOP pathway protein levels. Collectively, our findings indicate that ferroptosis is involved in S. aureus-induced mastitis via ER stress-mediated autophagy activation, implying a potential strategy for the prevention of S. aureus-associated diseases by targeting ferroptosis. In conclusion, the ROS-ER stress-autophagy axis is involved in regulating S. aureus-induced ferroptosis in MMECs. These findings not only provide a new potential mechanism for mastitis induced by S. aureus but also provide a basis for the treatment of other ferroptotic-related diseases.


Asunto(s)
Autofagia , Estrés del Retículo Endoplásmico , Ferroptosis , Mastitis , Infecciones Estafilocócicas , Staphylococcus aureus , Animales , Ferroptosis/efectos de los fármacos , Mastitis/microbiología , Mastitis/metabolismo , Mastitis/patología , Femenino , Staphylococcus aureus/fisiología , Infecciones Estafilocócicas/inmunología , Ratones , Ratones Endogámicos BALB C , Células Epiteliales/metabolismo , Factor de Transcripción Activador 4/metabolismo , Factor de Transcripción Activador 4/genética , Glándulas Mamarias Animales/patología , Glándulas Mamarias Animales/microbiología , Factor de Transcripción CHOP/metabolismo , Humanos , Transducción de Señal , Especies Reactivas de Oxígeno/metabolismo , Células Cultivadas
3.
Sci Adv ; 10(31): eadm7458, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39083608

RESUMEN

Nonreciprocal transmission, resulting from the breaking of Lorentz reciprocity, plays a pivotal role in nonreciprocal communication systems by enabling asymmetric forward and backward propagations. Metasurfaces endowed with nonreciprocity represent a compact and facile platform for manipulating electromagnetic waves in an unprecedented manner. However, most passive metasurfaces that achieve nonreciprocal transmissions are polarization dependent. While incorporation of active elements or nonlinear materials can achieve polarization-independent nonreciprocal metasurfaces, the complicated configurations limit their practical applications. To address this issue, we propose and demonstrate a passive and linear metasurface that combines magneto-optical and chiral effects, enabling polarization-independent isolation. The designed metasurface achieves a transmittance of up to 80%, with a high contrast between forward and backward propagations. Our work introduces a novel mechanism for nonreciprocal transmission and lays the foundation for the development of compact, polarization-insensitive nonreciprocal devices.

4.
ACS Appl Mater Interfaces ; 16(27): 34988-34996, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38920133

RESUMEN

The high performance of intermediate-to-low temperature solid oxide fuel cells (ILT-SOFCs) closely depends on the catalytic activity of the cathode material. However, most high-activity perovskite cathodes are rich in Sr and will arise from Sr segregation during the long-term working, resulting in the decay of activity and stability. Herein, by regulating the calcined way and temperature, a type of self-assembled nanocomposite perovskite cathode is developed, the stoichiometric SrCo0.7Fe0.2Sc0.1O3-δ (SCFSc) powder self-separates into a cubic phase (Pm3̅m, Sc-rich) and a tetragonal phase (P4/mmm, Sc-fewer). Meanwhile, a single cubic phase is prepared with the same formula via calcining the SCFSc pellet. It is found that the nanocomposite cathode shows better oxygen reduction reaction catalytic activity than single cubic SCFSc, caused by lower impedance of oxygen surface exchange and bulk diffusion. Particularly, the nanocomposite SCFSc cathode with the self-assembled heterointerfaces mitigates the Sr segregation and shows a peak power density of 1.17 W cm-2 at 700 °C and excellent stability for ∼101 h at 600 °C. This work provides a strategy for the development of nanocomposite cathodes to mitigate cation segregation and improve catalytic activity and stability.

5.
BMC Plant Biol ; 24(1): 391, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38735929

RESUMEN

BACKGROUND: Unreduced gamete formation during meiosis plays a critical role in natural polyploidization. However, the unreduced gamete formation mechanisms in Triticum turgidum-Aegilops umbellulata triploid F1 hybrid crosses and the chromsome numbers and compostions in T. turgidum-Ae. umbellulata F2 still not known. RESULTS: In this study, 11 T.turgidum-Ae. umbellulata triploid F1 hybrid crosses were produced by distant hybridization. All of the triploid F1 hybrids had 21 chromosomes and two basic pathways of meiotic restitution, namely first-division restitution (FDR) and single-division meiosis (SDM). Only FDR was found in six of the 11 crosses, while both FDR and SDM occurred in the remaining five crosses. The chromosome numbers in the 127 selfed F2 seeds from the triploid F1 hybrid plants of 10 crosses (no F2 seeds for STU 16) varied from 35 to 43, and the proportions of euploid and aneuploid F2 plants were 49.61% and 50.39%, respectively. In the aneuploid F2 plants, the frequency of chromosome loss/gain varied among genomes. The chromosome loss of the U genome was the highest (26.77%) among the three genomes, followed by that of the B (22.83%) and A (11.81%) genomes, and the chromosome gain for the A, B, and U genomes was 3.94%, 3.94%, and 1.57%, respectively. Of the 21 chromosomes, 7U (16.54%), 5 A (3.94%), and 1B (9.45%) had the highest loss frequency among the U, A, and B genomes. In addition to chromosome loss, seven chromosomes, namely 1 A, 3 A, 5 A, 6 A, 1B, 1U, and 6U, were gained in the aneuploids. CONCLUSION: In the aneuploid F2 plants, the frequency of chromosome loss/gain varied among genomes, chromsomes, and crosses. In addition to variations in chromosome numbers, three types of chromosome translocations including 3UL·2AS, 6UL·1AL, and 4US·6AL were identified in the F2 plants. Furthermore, polymorphic fluorescence in situ hybridization karyotypes for all the U chromosomes were also identified in the F2 plants when compared with the Ae. umbellulata parents. These results provide useful information for our understanding the naturally occurred T. turgidum-Ae. umbellulata amphidiploids.


Asunto(s)
Aegilops , Inestabilidad Cromosómica , Cromosomas de las Plantas , Hibridación Genética , Triticum , Triticum/genética , Cromosomas de las Plantas/genética , Aegilops/genética , Meiosis/genética , Triploidía , Poliploidía , Genoma de Planta
6.
Small ; : e2400316, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38716992

RESUMEN

Hematite is a promising photoanode material for photoelectrochemical water-splitting technology. However, the low current density associated with the low conductivity, low charge carrier mobility, and poor oxygen evolution catalytic activity is a challenging issue for the material. In this study, the challenge is addressed by introducing Germanium (Ge) doping, coupled with the use of FeCoNi-Bi as a co-catalyst. Ge doping not only increases the conductivity and charge carrier concentration of the hematite photoanode, but also induces nanopores, thereby expanding its electrochemical reactive surface area to facilitate the oxygen evolution reaction. In the meantime, the FeCoNi-Bi cocatalyst electrodeposited onto the surface of Ge-doped hematite, improves the oxygen evolution reaction performance. As a result, the obtained photoanode achieves a photocurrent density of 2.31 mA cm-2 at 1.23 VRHE, which is three times higher than that of hematite (0.72 mA cm-2). Moreover, a new analytical method is introduced to scrutinize both the positive and negative effects of Ge doping and FeCoNi-Bi cocatalyst on the photoanode performance by decoupling the photoelectrochemical process steps. Overall, this study not only enhances the performance of hematite photoanodes but also guides their rational design and systematic assessment.

7.
J Colloid Interface Sci ; 671: 664-679, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38820850

RESUMEN

Bi2O2CO3/In(OH)3 (BON) photocatalysts were synthesized by a one-pot method and loaded onto polyvinylidene fluoride (PVDF) membranes to obtain a Bi2O2CO3/In(OH)3/PVDF (BON-M) catalytic membrane system. The catalytic membranes demonstrated complete degradation of tetracycline within 40 min under visible light. They demonstrated robust photocatalytic activity across a broad pH range (5-11) and in the presence of coexisting ions. The membranes demonstrated excellent self-cleaning performance. Following exposure to light, the irreversible contamination decreased from 27.1% to 4.7% and the membrane's permeability was almost completely restored. Moreover, the charge transfer mechanism at the S-scheme heterojunction interface of BON was demonstrated by Density functional theory and in-situ X-ray Photoelectron Spectroscopy characterisation, and the active sites involved in tetracycline's degradation were identified. Meanwhile, the mechanism of the "anemone effect" of BON-M was demonstrated in conjunction with Electron paramagnetic resonance, and the intrinsic Some factors enhancing the membranes' photocatalytic activity are specified.

8.
ACS Appl Mater Interfaces ; 16(15): 19764-19770, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38577833

RESUMEN

Two-dimensional van der Waals (2D vdW) materials are widely used in spin-orbit torque (SOT) devices. Recent studies have demonstrated the low crystal symmetry and large spin Hall conductivity of 2D vdW ZrSe3, indicating its potential applications in low-power SOT devices. Here, we study the interfacial contribution of SOTs and current-induced magnetization switching in the ZrSe3/Py (Ni80Fe20) and ZrSe3/Cu/Py heterostructures. SOT efficiencies of samples are detected by the spin-torque ferromagnetic resonance (ST-FMR), and out-of-plane damping-like torque (τB) is observed. The ratio between τB and the field-like torque (τA) decreases from 0.175 to 0.138 when inserting 1 nm Cu at the interface and then drops to 0.001 when the thickness of Cu intercalation is 2 nm, indicating that Cu intercalation inhibits the τB component of SOT. Moreover, the SOT efficiency is increased from 3.05 to 5.21, which may be attributed to the Cu intercalation being beneficial to improve the interface between Py and ZrSe3. Theoretical calculation has shown that the Cu spacer can change the conductivity of ZrSe3 from semiconductor to conductor, thereby decreasing the Schottky barrier and increasing the transmission efficiency of the spin current. Furthermore, magneto-optical Kerr effect (MOKE) microscopy is employed to verify the current-driven magnetization switching in these structures. In comparison to the ZrSe3/Py bilayer, the critical current density of ZrSe3/Cu/Py is reduced when inserting 1 nm Cu, demonstrating the higher SOT efficiency and lower power consumption in ZrSe3/Cu/Py structures.

9.
Acad Radiol ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38653598

RESUMEN

BACKGROUND: Epicardial adipose tissue (EAT) accumulation plays a key role in the progression myocardial infarction (MI) and diabetes. Diabetic patients have elevated risk of major adverse cardiac events (MACEs) compared to non-diabetic patients. We aimed to investigate the prognostic value of EAT volume in MI patients with and without diabetes. METHODS: This study included 458 MI patients who underwent cardiac computed tomography (CT) imaging and received successful stent implantation. EAT volume was quantified with cardiac CT imaging. Sub-study stratification of patients by diabetes status was further analyzed. Cox proportional hazards regression models were applied to evaluate the association between EAT volume and MACEs. RESULTS: Diabetes was identified in 135 of the 458 patients (29.5%). EAT volume was significantly higher in diabetes than non-diabetes. During a median follow-up of 1154 days, MACEs occurred more frequently in patients with versus without diabetes. EAT volume was independent predictor of MACEs in all MI patients after adjustment for risk factors, and showed good predictive value in the evaluation of MACEs. Moreover, EAT volume was also significantly associated with MACEs after adjustment for risk factors in diabetes and non-diabetes in the subgroup analysis. CONCLUSION: MI patients with diabetes had higher EAT volume and experienced higher rate of MACEs compared to non-diabetes. EAT volume is an independent risk of prognosis of MI, regardless of the diabetes status.

10.
Molecules ; 29(8)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38675671

RESUMEN

Atmospheric water harvesting (AWH) is considered a promising strategy for sustainable freshwater production in landlocked and arid regions. Hygroscopic salt-based composite sorbents have attracted widespread attention for their water harvesting performance, but suffer from aggregation and leakage issues due to the salting-out effect. In this study, we synthesized a PML hydrogel composite by incorporating zwitterionic hydrogel (PDMAPS) and MIL-101(Cr) as a host for LiCl. The PML hydrogel was characterized using various techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR), and thermogravimetric analysis (TGA). The swelling properties and water vapor adsorption-desorption properties of the PML hydrogel were also assessed. The results demonstrate that the MIL-101(Cr) was uniformly embedded into PDMAP hydrogel, and the PML hydrogel exhibits a swelling ratio of 2.29 due to the salting-in behavior. The PML hydrogel exhibited exceptional water vapor sorption capacity of 0.614 g/g at 298 K, RH = 40% and 1.827 g/g at 298 K, RH = 90%. It reached 80% of its saturated adsorption capacity within 117 and 149 min at 298 K, RH = 30% and 90%, respectively. Additionally, the PML hydrogel showed excellent reversibility in terms of water vapor adsorption after ten consecutive cycles of adsorption-desorption. The remarkable adsorption capacity, favorable adsorption-desorption rate, and regeneration stability make the PML hydrogel a potential candidate for AWH. This polymer-MOF synergistic strategy for immobilization of LiCl in this work offers new insights into designing advanced materials for AWH.

11.
Opt Lett ; 49(7): 1840-1843, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38560878

RESUMEN

We introduce the concept of polarized vortex Smith-Purcell radiation by the interaction of an electron beam and cascaded metasurfaces. The spin and orbital angular momenta of Smith-Purcell radiation are determined by the cascaded metasurface that consists of a grating and a phase gradient metasurface. The grating converts the electron beam radiation into the desired polarized light, while the phase gradient metasurface generates the vortex light. Furthermore, the vortex Smith-Purcell radiation with linear and circular polarizations can be achieved by the various cascaded metasurfaces. In particular, the conversion of chirality in the Smith-Purcell radiation carrying circular polarization is accompanied by the alteration of positive and negative topological charges. This work paves the way for generating polarized vortex electron radiation and is beneficial to promote the development of free-electron-driven devices.

12.
Molecules ; 29(5)2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38474527

RESUMEN

The high toxicity of arsenic (As) can cause irreversible harm to the environment and human health. In this study, the chlorin e6 (Ce6), which emits fluorescence in the infrared region, was introduced as the luminescence center, and the addition of copper ion (Cu2+) and As(V) provoked a regular change in fluorescence at 652 nm, whereas that of As(III) was 665 nm, which was used to optionally detect Cu2+, arsenic (As(III), and As(V)). The limit of detection (LOD) values were 0.212 µM, 0.089 ppm, and 1.375 ppb for Cu2+, As(III), and As(V), respectively. The developed method can be used to determine Cu2+ and arsenic in water and soil with good sensitivity and selectivity. The 1:1 stoichiometry of Ce6 with Cu2+ was obtained from the Job plot that was developed from UV-visible spectra. The binding constants for Cu2+ and As(V) were established to be 1.248 × 105 M-1 and 2.35 × 1012 M-2, respectively, using B-H (Benesi-Hildebrand) plots. Fluorescence lifetimes, B-H plots, FT-IR, and 1H-NMR were used to postulate the mechanism of Cu2+ fluorescence quenching and As(V) fluorescence restoration and the interactions of the two ions with the Ce6 molecule.


Asunto(s)
Arsénico , Clorofilidas , Porfirinas , Humanos , Cobre/química , Espectroscopía Infrarroja por Transformada de Fourier , Iones , Espectrometría de Fluorescencia , Colorantes Fluorescentes/química
13.
Biomed Pharmacother ; 174: 116485, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38518602

RESUMEN

BACKGROUND: Glucagon-like peptide-1 (GLP-1)/glucagon (GCG) dual receptor agonists with different receptor selectivity are under investigation and have shown significant improvement in both weight loss and glycemic control, but the optimal potency ratio between the two receptors to balance efficacy and safety remains unclear. EXPERIMENTAL APPROACH: We designed and constructed several dual receptor agonists with different receptor potency ratios using Fc fusion protein technology. The long-term effects of the candidates on body weight and metabolic dysfunction-associated steatotic liver disease (MASLD) were evaluated in diet-induced obese (DIO) model mice, high-fat diet (HFD)-ob/ob mice and AMLN diet-induced MASLD mice. Repeat dose toxicity assays were performed to investigate the safety profile of the candidate (HEC-C070) in Sprague Dawley (SD) rats. KEY RESULTS: The high GCG receptor (GCGR) selectivity of HEC-C046 makes it more prominent than other compounds for weight loss and most MASLD parameters but may lead to safety concerns. The weight change of HEC-C052 with the lowest GCG agonism was inferior to that of selective GLP-1 receptor agonist (GLP-1RA) semaglutide in DIO model mice. The GLP-1R selectivity of HEC-C070 with moderate GCG agonism has a significant effect on weight loss and liver function in obese mice, and its lowest observed adverse effect level (LOAEL) was 30 nmol/kg in the repeat dose toxicity study. CONCLUSION: We compared the potential of the Fc fusion protein GLP-1/GCG dual receptor agonists with different receptor selectivity to provide the setting for future GLP-1/GCG dual receptor agonists to treat obesity and MASLD.


Asunto(s)
Dieta Alta en Grasa , Péptido 1 Similar al Glucagón , Receptor del Péptido 1 Similar al Glucagón , Fragmentos Fc de Inmunoglobulinas , Obesidad , Receptores de Glucagón , Proteínas Recombinantes de Fusión , Animales , Humanos , Ratones , Ratas , Dieta Alta en Grasa/efectos adversos , Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Péptidos Similares al Glucagón/farmacología , Fragmentos Fc de Inmunoglobulinas/farmacología , Ratones Endogámicos C57BL , Ratones Obesos , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Ratas Sprague-Dawley , Receptores de Glucagón/agonistas , Receptores de Glucagón/metabolismo , Proteínas Recombinantes de Fusión/farmacología , Pérdida de Peso/efectos de los fármacos
14.
Animals (Basel) ; 14(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38473070

RESUMEN

With the increase in breeding density of Exopalaemon carinicauda, appendage breakage may occur, which seriously affects survival and economic benefits. To study the limb regeneration process of E. carinicauda, we induced autotomy of the pereopods. After a period of time, wound swelling disappeared, the pigment gradually accumulated, and a tawny film subsequently formed in the wound. The healing period of the wound occurred 24 h after autotomy, and the blastema formation stage occurred 48 h after autotomy. After 4 days of cutting, the limb buds began to differentiate, grow, and expand rapidly, and this process lasted approximately 15 days. Microscopic observations revealed significant changes in the type and number of associated cells including outer epithelial cells, granulocytes, embryonic cells, columnar epidermal cells, elongated cells, and blastoma cells, during the process from limb fracture to regeneration. A comparative transcriptome analysis identified 1415 genes differentially expressed between the J0h (0 h post autotomy) and J18h (18 h post autotomy), and 3952 and 4366 differentially expressed genes for J0 and J14d (14 days post autotomy) and J18h and J14d, respectively. Some of these genes may be related to muscle growth or molting, as indicated by the presence of troponin C, chitinase, actin, innexin, and cathepsin L. As a functional gene involved in epidermal formation, the mRNA expression level of the innexin inx2 in the pereopod of E. carinicauda changed significantly in the experimental groups (p < 0.05). The results of this study contribute to existing knowledge of regeneration mechanisms in crustaceans.

15.
Plant Divers ; 46(1): 101-115, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38343597

RESUMEN

Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau, China relies on discovering new plant fossils. The Qaidam Basin has long been regarded as an ideal 'field laboratory' to investigate the paleoclimate and paleobiological evolution of the northern Tibetan Plateau. However, fossil angiosperms from the Qaidam Basin are rare, and our knowledge of its paleovegetation is poor. Here, we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin (Huatugou area). Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus grandis. These findings, together with other reported fossil plants from the same locality, reveal a close floristic linkage between the Qaidam Basin and Europe during the Oligocene. The northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late Paleogene. This floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies, which transported moisture and provided favorable climatic conditions. Indeed, fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest, which differs from the region's modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene.

16.
Antioxidants (Basel) ; 13(1)2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38247528

RESUMEN

Sperm motility is an important factor in the migration of sperm from the uterus to the oviduct. During sperm preservation in vitro, sperm generates excessive ROS that damages its function. This study aims to investigate whether the addition of pyrroloquinoline quinone (PQQ) to the diluted medium could improve chilled ram sperm quality, and then elucidates the mechanism. Ram semen was diluted with Tris-citric acid-glucose (TCG) medium containing different doses of PQQ (0 nM, 10 nM, 100 nM, 1000 nM, 10,000 nM), and stored at 4 °C. Sperm motility patterns, plasma membrane integrity, acrosome integrity, mitochondrial membrane potential, reactive oxygen species (ROS) levels, malondialdehyde (MDA) levels, superoxide dismutase (SOD) activity, and ATP levels were measured after preservation. Furthermore, the expressions of NADH dehydrogenase 1 (MT-ND1) and NADH dehydrogenase 6 (MT-ND6) in sperm were also detected by western blotting. In addition, sperm capacitation and the ability of sperm to bind to the zona pellucina were also evaluated. It was observed that the addition of PQQ significantly (p < 0.05) improved ram sperm motility, membrane integrity, and acrosome integrity during preservation. The percentage of sperm with high mitochondrial membrane potential in the PQQ treatment group was much higher than that in the control. In addition, supplementation of PQQ also decreased the sperm MDA and ROS levels, while increasing ATP levels. Interestingly, the levels of MT-ND1 and MT-ND6 protein in sperm treated with PQQ were also higher than that of the control. Furthermore, the addition of 100 nM PQQ to the medium decreased ROS damage in MT-ND1 and MT-ND6 proteins. The addition of 100 nM PQQ significantly (p < 0.05) increased protein tyrosine phosphorylation in ram sperm after induced capacitation. Furthermore, the value of the sperm-zona pellucida binding capacity in the 100 nM PQQ treatment group was also much higher than that of the control. Overall, during chilled ram- sperm preservation, PQQ protected ram sperm quality by quenching the ROS levels to reduce ROS damage and maintain sperm mitochondrial function, and preserved the sperm's high ability of fertilization.

17.
FASEB J ; 38(2): e23383, 2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38197892

RESUMEN

Mastitis is the most frequent disease of cows and has well-recognized detrimental effects on animal wellbeing and dairy farm profitability. With the advent of the postantibiotic era, alternative antibiotic agents, especially probiotics, have received increasing attention in the treatment of mastitis. Based on research showing that Lactobacillus reuteri (L. reuteri) has anti-inflammatory effects, this study explored the protective effects and mechanisms of L. reuteri against mastitis induced by Staphylococcus aureus (S. aureus) in mice. First, mice with S. aureus-induced mastitis were orally administered L. reuteri, and the inflammatory response in the mammary gland was observed. The results showed that L. reuteri significantly inhibited S. aureus-induced mastitis. Moreover, the concentration of oxytocin (OT) and protein expression of oxytocin receptor (OTR) were measured, and inhibition of OTR or vagotomy reversed the protective effect of L. reuteri or its culture supernatant (LCS) on S. aureus-induced mastitis. In addition, in mouse mammary epithelial cells (MMECs), OT inhibited the inflammation induced by S. aureus by inhibiting the protein expression of OTR. It was suggested that L. reuteri protected against S. aureus-induced mastitis by releasing OT. Furthermore, microbiological analysis showed that the composition of the microbiota was altered, and the relative abundance of Lactobacillus was significantly increased in gut and mammary gland after treatment with L. reuteri or LCS. In conclusion, our study found the L. reuteri inhibited the mastitis-induced by S. aureus via promoting the release of OT, and treatment with L. reuteri increased the abundance of Lactobacillus in both gut and mammary gland.


Asunto(s)
Microbioma Gastrointestinal , Limosilactobacillus reuteri , Mastitis , Infecciones Estafilocócicas , Femenino , Humanos , Animales , Bovinos , Ratones , Oxitocina/farmacología , Oxitocina/uso terapéutico , Staphylococcus aureus , Mastitis/terapia , Receptores de Oxitocina , Lactobacillus
18.
J Biol Chem ; 300(3): 105671, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38272222

RESUMEN

Poly(ADP-ribosyl)ation (PARylation) is a critical posttranslational modification that plays a vital role in maintaining genomic stability via a variety of molecular mechanisms, including activation of replication stress and the DNA damage response. The nudix hydrolase NUDT16 was recently identified as a phosphodiesterase that is responsible for removing ADP-ribose units and that plays an important role in DNA repair. However, the roles of NUDT16 in coordinating replication stress and cell cycle progression remain elusive. Here, we report that SETD3, which is a member of the SET-domain containing protein (SETD) family, is a novel substrate for NUDT16, that its protein levels fluctuate during cell cycle progression, and that its stability is strictly regulated by NUDT16-mediated dePARylation. Moreover, our data indicated that the E3 ligase CHFR is responsible for the recognition and degradation of endogenous SETD3 in a PARP1-mediated PARylation-dependent manner. Mechanistically, we revealed that SETD3 associates with BRCA2 and promotes its recruitment to stalled replication fork and DNA damage sites upon replication stress or DNA double-strand breaks, respectively. Importantly, depletion of SETD3 in NUDT16-deficient cells did not further exacerbate DNA breaks or enhance the sensitivity of cancer cells to IR exposure, suggesting that the NUDT16-SETD3 pathway may play critical roles in the induction of tolerance to radiotherapy. Collectively, these data showed that NUDT16 functions as a key upstream regulator of SETD3 protein stability by reversing the ADP-ribosylation of SETD3, and NUDT16 participates in the resolution of replication stress and facilitates HR repair.


Asunto(s)
ADP-Ribosilación , Neoplasias , Roturas del ADN de Doble Cadena , Daño del ADN , Reparación del ADN , Neoplasias/genética , Neoplasias/radioterapia , Poli(ADP-Ribosa) Polimerasa-1/genética , Procesamiento Proteico-Postraduccional , Humanos , Línea Celular , Pirofosfatasas/genética , Pirofosfatasas/metabolismo , Histona Metiltransferasas/genética , Histona Metiltransferasas/metabolismo
19.
Phys Chem Chem Phys ; 25(42): 29201-29210, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37872864

RESUMEN

Metal-organic frameworks (MOFs) offer promising opportunities for modifying energetic materials due to their micro-porous structure and high performance. In this study, we present a novel green MOF named cyclodextrin-MOF (CD-MOF), which incorporates potassium ions, synthesized using a simple methanol vapor diffusion approach. The CD-MOF incorporates potassium ions and enhances propellant performance through intermolecular force optimization with nitrocellulose (NC). Molecular dynamics simulations reveal stronger interactions between the CD-MOF and NC. The loading of the CD-MOF within NC forms a stable structure with resistance to migration and defense against crystalline precipitation and water absorption. Notably, in static combustion and pyrolysis tests, the CD-MOF exhibits efficient flame and flash inhibition. The thermal degradation and cauterization of the CD-MOF resulted in the formation of a complex microporous material capable of absorbing flammable and harmful gases such as CO, NO, NO2, and N2O. These findings shed light on the superior performance of the CD-MOF compared to conventional inorganic salts, and the comprehensive characterization and molecular simulations provide insights into the unique properties and applications of the CD-MOF, emphasizing its significant contribution to the field of green propellants.

20.
Opt Express ; 31(20): 32865-32874, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37859079

RESUMEN

Metamaterials, thoughtfully designed, have demonstrated remarkable success in the manipulation of electromagnetic waves. More recently, deep learning can advance the performance in the field of metamaterial inverse design. However, existing inverse design methods based on deep learning often overlook potential trade-offs of optimal design and outcome diversity. To address this issue, in this work we introduce contrastive learning to implement a simple but effective global ranking inverse design framework. Viewing inverse design as spectrum-guided ranking of the candidate structures, our method creates a resemblance relationship of the optical response and metamaterials, enabling the prediction of diverse structures of metamaterials based on the global ranking. Furthermore, we have combined transfer learning to enrich our framework, not limited in prediction of single metamaterial representation. Our work can offer inverse design evaluation and diverse outcomes. The proposed method may shrink the gap between flexibility and accuracy of on-demand design.

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