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1.
Front Endocrinol (Lausanne) ; 15: 1440182, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39359417

RESUMEN

Objective: This study aimed to evaluate the effectiveness of oral L-carnitine administration in patients after treatment failure to lay the groundwork for targeted in vivo use. Methods and materials: A total of 515 In Vitro Fertilization (IVF) patients undergoing subsequent cycles were included after applying exclusion criteria. They were divided into a control group of 362 patients and a study group of 153 patients who received oral L-carnitine until oocyte retrieval.140 patients were matched according to maternal age, infertility duration, body mass index (BMI), day three top-quality embryos rate, by propensity score matching (PSM). The study investigated the relationship between L-carnitine treatment and in vivo oocyte maturation, normal fertilization, and subsequent embryo development. Results: Following PSM, initial differences in BMI and Day3 top-quality embryo rate between groups were nullified, we created two comparable cohorts with highly similar characteristics. In the subsequent cycles, the study group showed significant improvements in in vivo oocyte maturation rate at retrieval (p=0.002), normal in vitro fertilization rate (p=0.003), blastocyst formation rate (p=0.003), and usable blastocyst rate compared to controls. Although there was no significant difference in the top-quality embryo rate on Day 3, the study group showed a 10% increase in the upper quartile (55.35% vs. 66.67%). The cumulative clinical pregnancy and live birth rates showed a significant improvement (59.82% vs. 68.42%,p=0.004, 47.41% vs. 59.80%, p=0.002). Furthermore, self-control analysis revealed substantial enhancements (p<0.001) in all outcome measures following L-carnitine administration, resulting in the birth of 74 healthy neonates without congenital anomalies. Conclusion: We theorized that daily oral intake of L-carnitine before oocyte retrieval could boost oocyte quality and embryonic development, thus improving IVF outcomes. Ongoing investigations hold the potential to offer valuable insights into the applications and mechanisms underlying the therapeutic effectiveness of L-carnitine.


Asunto(s)
Carnitina , Fertilización In Vitro , Puntaje de Propensión , Humanos , Carnitina/administración & dosificación , Femenino , Adulto , Fertilización In Vitro/métodos , Embarazo , Administración Oral , Índice de Embarazo , Recuperación del Oocito/métodos , Infertilidad Femenina/tratamiento farmacológico , Enfermedades del Ovario/tratamiento farmacológico , Resultado del Tratamiento , Estudios Retrospectivos
2.
Plant Physiol ; 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39351808

RESUMEN

Coat protein complex II (COPII) vesicles play crucial roles in mediating the endoplasmic reticulum (ER) exit of newly synthesized proteins to the Golgi in eukaryotic cells. However, the molecular functions of COPII components and their functional diversifications in plant seeds remain obscure. Here, we showed that the rice (Oryza sativa) glutelin precursor accumulation12 (gpa12) mutant is defective in storage protein export from the ER, resulting in the formation of aggregated protein bodies. Map-based cloning revealed that GPA12 encodes a COPII outer layer protein, Sec13a, that mainly localizes to endoplasmic reticulum exit sites (ERES) and partially localizes to the Golgi. Biochemical experiments verified that Sec13a physically interacts with Sec31 and Sec16, and mutation in Sec13 compromises its interaction with Sec31 and Sec16, thereby affecting the membrane association of the inner complex components Sar1b and Sec23c. Apart from Sec13a, the rice genome encodes two other Sec13 isoforms, Sec13b and Sec13c. Notably, we observed an abnormal accumulation of globular ER structures in the sec13bc double mutant but not in the single mutants, suggesting a functional redundancy of Sec13b and Sec13c in modulating ER morphology. Taken together, our results substantiated that Sec13a plays an important role in regulating storage protein export from the ER, while Sec13b and Sec13c are required for maintaining ER morphology in rice endosperm cells. Our findings provide insights into the functional diversification of COPII components in plants.

3.
J Chromatogr A ; 1736: 465333, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39260151

RESUMEN

A zwitterionic stationary phase comprising pyridinium cations and sulfonate anions was successfully developed through thiol-ene click chemistry. Using seven polar small molecules as probes, the zwitterionic stationary phase showed high separation selectivity and excellent column efficiency (35,200-54,800 plates/m) compared with two commercial columns. The influence of water proportion, salt concentration, and pH in the mobile phase, and column temperature, on the retention of six polar compounds was examined. The retention mechanism was explored by three hydrophilic retention models, Tanaka test and linear solvation energy relationship analysis. For the analysis of sample dairy products (milk powder, milk, and yogurt), the stationary phase was operated in hydrophilic interaction chromatography mode without the addition of buffer salts, facilitating rapid and efficient detection and quantification of melamine. The LOD and LOQ are 0.04 mg⋅g-1 and 0.13 mg⋅g-1, respectively, and the recovery rate is 90.3 - 102.8 %. The zwitterionic stationary phase has the advantages of simple preparation, good method reproducibility, good selectivity and high precision.

4.
J Chromatogr A ; 1736: 465381, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39321754

RESUMEN

Under the principle of similar compatibility, researchers have developed various polarity extractants corresponding to a class of chemicals. Separating different polarities chemicals with one extractant effectively has become a novel research trend in separation science. Given the complexity of environmental sample matrices and the significant differences in polarity and solubility of various compounds, the introduction of hydrophilic groups to hydrophobic material skeletons can lead to sorbents with hydrophilic-lipophilic balance (HLB) property and thus improve their extraction performance for substances with different polarities. In this work, a hypercrosslinked polymer (HCPPz-TPB), designated as HLB, was synthesized by incorporating polar pyrazine and nonpolar triphenylbenzene molecules within each other. Subsequently, a core-shell magnetic composite material was obtained by encapsulating magnetic Fe3O4 nanoparticles in HCPPz-TPB. The material was applied as an adsorbent for magnetic solid phase extraction (MSPE) and combined with a high-performance liquid chromatography-photodiode array detector (HPLC-PDA) to enrich, separate, and detect seven polar contaminants in environmental water samples. The proposed approach, Fe3O4@SiO2@HCPPz-TPB-MSPE-HPLC-PDA, is characterized by its outstanding high sensitivity, low detection limits, wide linear range, and good reproducibility. The method demonstrated satisfactory linearity in the range of 0.05-2 µg mL-1 with R2 values between 0.9969 and 0.9997; the limits of detection (LOD) were observed to be within the range of 0.0019-0.016 µg L-1, and limits of quantification (LOQ) was observed to be within the range of 0.0064-0.054 µg L-1 range with good precision. The recoveries of the different contaminants in the environmental samples ranged from 83.61 to 116.46% (RSD≤10.56, n = 5). The new hydrophilic-lipophilic balance extractant is highly efficient, sensitive, and precise for extracting different polar pollutants. The findings demonstrate that the Fe3O4@SiO2@HCPPz-TPB display a remarkable affinity for multiple targets, driven by complex interactions including multi-stackings and hydrogen bonding as a sorbent. The synthesized Fe3O4@SiO2@HCPPz-TPB may be employed in diverse applications, including extraction, removal, and determination of diverse trace multi-target analytes in complex media.

5.
Adv Mater ; : e2407409, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235391

RESUMEN

Surface coatings are designed to mitigate pervasive biofouling herald, a new era of surface protection in complex biological environments. However, existing strategies are plagued by persistent and recurrent biofilm attachment, despite the use of bactericidal agents. Herein, a chiral metal-organic framework (MOF)-based coating with conformal microstructures to enable a new anti-biofouling mode that involves spontaneous biofilm disassembly followed by bacterial eradication is developed. A facile and universal metal-polyphenol network (MPN) is designed to robustly anchor the MOF nanoarmor of biocidal Cu2+ ions and anti-biofilm d-amino acid ligands to a variety of substrates across different material categories and surface topologies. Incorporating a diverse array of chiral amino acids endows the resultant coatings with widespread signals for biofilm dispersal, facilitating copper-catalyzed chemodynamic reactions and inherent mechano-bactericidal activities. This synergistic mechanism yields unprecedented anti-biofouling efficacy elucidated by RNA-sequencing transcriptomics analysis, enhancing broad-spectrum antibacterial activities, preventing biofilm formation, and destroying mature biofilms. Additionally, the chelation-directed amorphous/crystalline coatings can activate photoluminescent properties to inhibit the settlement of microalgae biofilms. This study provides a distinctive perspective on chirality-enhanced antimicrobial behaviors and pioneers a rational pathway toward developing next-generation anti-biofouling coatings for diverse applications.

6.
Bioorg Chem ; 151: 107709, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39137599

RESUMEN

Ginger is an important cooking spice and herb worldwide, and scientific research has gradually confirmed the effect of ginger on preventing hair loss. Cedrol (CE) is a small sesquiterpene molecule in ginger and its external administration (EA) has shown hope in promoting hair growth, and alternative administration mode has become a potential treatment scheme to improve the efficacy of CE. The purpose of this study is to evaluate the effects of oral administration (OA) and EA of CE on hair regeneration of C57BL/6 alopecia areata (AA) mice induced by cyclophosphamide (CP) and to clarify the potential hair growth mechanism of CE in AA model in vitro and in vivo. The results showed that CE-OA has a shorter hair-turning black time and faster hair growth rate, and can lessen hair follicle damage induced by CP and promote hair follicle cell proliferation. Its effect is superior to CE-EA. At the same time, CE can increase the cytokines IFN-γ, IL-2, and IL-7 in the serum of mice, and decrease the expression of adhesion factors ICAM-1 and ELAM-1, thus alleviating the immunosuppression induced by CP. Mechanism research shows that CE regulates the JAK3/STAT3 signaling pathway, activates the Wnt3α/ß-catenin germinal center, and ameliorates oxidative stress induced by CP, thus promoting the proliferation of hair follicle cells and reversing AA. These results provide a theoretical basis for understanding the anti-AA mechanism of CE-OA, indicating that CE can be used as raw material for developing oral hair growth drugs.


Asunto(s)
Ratones Endogámicos C57BL , Sesquiterpenos , Zingiber officinale , Animales , Zingiber officinale/química , Administración Oral , Ratones , Sesquiterpenos/farmacología , Sesquiterpenos/química , Cabello/efectos de los fármacos , Cabello/química , Proliferación Celular/efectos de los fármacos , Regeneración/efectos de los fármacos , Folículo Piloso/efectos de los fármacos , Folículo Piloso/metabolismo , Estructura Molecular , Masculino , Relación Dosis-Respuesta a Droga , Alopecia Areata/tratamiento farmacológico , Relación Estructura-Actividad , Ciclofosfamida/farmacología , Sesquiterpenos Policíclicos
7.
ACS Appl Mater Interfaces ; 16(35): 46889-46896, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39169801

RESUMEN

P-type hydrogenated nanocrystalline silicon (nc-Si:H) has been used as a hole-selective layer for efficient n-type crystalline silicon heterojunction (SHJ) solar cells. However, the presence of an additional valence band offset at the interface between intrinsic amorphous hydrogenated silicon and p-type nc-Si:H films will limit the hole carrier transportation. In this work, it has been found that when a heavily boron-doped silicon oxide layer deposited with high hydrogen dilution to silane (pB) was inserted into their interface, the fill factor of SHJ solar cells increases 3% absolutely because of the reduced valence band offset and the increased opportunity to provide a hopping tunnel assisted by the doping energy level and valence band tail states. Furthermore, the additional boron incorporation in intrinsic amorphous silicon adjacent to pB helps to enhance the built-in electric field, thus increasing the hole selectivity. By these means, the power conversion efficiency was improved from 23.9% to approximately 25%.

8.
Bioorg Chem ; 152: 107758, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39216197

RESUMEN

GFRS is the conversion product of Panax ginseng Meyer berry after citric acid heat treatment, which is rich in rare ginsenosides. However, the anti-melanin role of GFRS in the regulation of skin pigmentation and its material basis remains unclear. To compare the anti-melanin activity before and after citric acid heat treatment, we determined the effects of GFS and GFRS on tyrosinase activity and melanin lever under α-MSH stimulation and found the potential anti-melanin effect of GFRS. Further, Western blot and immunofluorescence methods were used to reveal the mechanism by which GFRS detects anti-melanin activity by promoting autophagy flux levels. In zebrafish models, GFRS inhibited endogenous melanin and tyrosinase better than arbutin and promoted the accumulation of autophagy levels in vivo. To determine the material basis of the anti-melanin effect of GFRS, HPLC was used to isolate and prepare 12 ginsenosides from GFRS, and their activity evaluation and structure-activity relationship analysis were performed. The results showed that the inhibitory effect of GFRS on melanin was Rg3 > Rg5 > Rk1 > Rd. Molecular docking showed that their docking fraction with mushroom tyrosinase was significantly better than that of arbutin, but the presence of C-20 glycosylation decreased the anti-melanin activity of Rd. To maximize the content of Rg3, Rg5, and Rk1, we optimized the process by using citric acid heat treatment of ginsenoside Rd and found that citric acid heat treatment at 100°C almost completely transformed Rd and obtained a high content of active ingredients. In summary, our data demonstrated that GFRS exerted anti-melanin effects by inducing autophagy. It was further revealed that Rg3, Rg5, and Rk1, as effective active components, could be enriched by the improved process of converting ginsenoside Rd by citric acid heat treatment.


Asunto(s)
Autofagia , Ácido Cítrico , Ginsenósidos , Calor , Melaninas , Panax , Pez Cebra , Panax/química , Melaninas/metabolismo , Melaninas/antagonistas & inhibidores , Ginsenósidos/farmacología , Ginsenósidos/química , Ginsenósidos/aislamiento & purificación , Animales , Relación Estructura-Actividad , Autofagia/efectos de los fármacos , Ácido Cítrico/química , Ácido Cítrico/farmacología , Estructura Molecular , Frutas/química , Simulación del Acoplamiento Molecular , Relación Dosis-Respuesta a Droga , Monofenol Monooxigenasa/metabolismo , Monofenol Monooxigenasa/antagonistas & inhibidores
9.
Se Pu ; 42(9): 881-890, 2024 Sep.
Artículo en Chino | MEDLINE | ID: mdl-39198947

RESUMEN

Phthalate esters (PAEs) are used as additives to enhance the pliability and malleability of plastics. These substances frequently migrate from packaging materials to vegetable oils because of the absence of covalent bonds. Over time, this migration could result in the accumulation of PAEs in the human body through ingestion, contributing to various diseases. Therefore, accurate qualitative and quantitative analyses of PAEs in vegetable oils are imperative to assess the origins of contamination and investigate their toxicity, degradation, migration, and transformation patterns. However, the concentration of PAEs in most samples is low, and the composition of vegetable oils is complex. Thus, PAEs must be enriched and purified using appropriate sample pretreatment procedures before analysis. Common methods for pretreating PAEs in oil include solid-phase extraction (SPE), dispersive SPE, and magnetic SPE. These techniques require time-consuming and labor-intensive procedures such as oil dissolution, solvent extraction, and degreasing. These approaches also require numerous solvents and containers, increasing the risk of sample cross-contamination. Solid-phase microextraction (SPME) integrates sampling, extraction, purification, concentration, and injection into a single process, significantly accelerating analytical testing and reducing the potential for sample cross-contamination. In headspace (HS) mode, the analytes achieve equilibrium on the coating and are extracted in the gas phase. The fibers are shielded from nonvolatile and high-relative molecular mass substances in the sample matrix. Thus, SPME is an ideal method for extracting volatile compounds in vegetable oils. When HS-SPME coupled with gas chromatography-mass spectrometry (GC-MS), it can achieve the rapid screening of PAEs in vegetable oil. In this study, an SPME with cyclodextrin-based hypercrosslinked polymers (BnCD-HCP) coated on stainless steel fibers was employed to extract PAEs from vegetable oil. The structure and morphology of the polymers were characterized using Fourier-transform infrared spectroscopy, nuclear magnetic spectroscopy, and scanning electron microscopy. BnCD-HCP exhibited high stability and diverse interactions, including π-π, hydrophobic, and host-guest interactions. The oil samples were incubated with methanol, and the PAEs were extracted from the headspace using the probe. The optimal extraction parameters included an extraction time of 20 min, extraction temperature of 50 ℃, desorption time of 4 min, and desorption temperature of 275 ℃. The BnCD-HCP/HS-SPME method was evaluated under optimized experimental conditions. The limits of detection (LODs) and quantification (LOQs) were determined by applying signal-to-noise ratios (S/N) of 3 and 10, respectively. Method accuracy was evaluated using relative standard deviations (RSDs). Single-needle precision was evaluated by conducting three consecutive analyses at 3 h intervals within a day. Inter-needle precision was assessed by conducting the same analyses (three replicates) with differently coated fibers. The 12 PAE compounds exhibited good linearity with correlation coefficients (R2) of at least 0.99. The LODs and LOQs ranged from 0.21 to 3.74 µg/kg and from 0.69 to 12.34 µg/kg, respectively. The RSDs were in the range of 1.8%-11.4% and 5.1%-13.9% for the single-needle and needle-to-needle methods, respectively. The proposed method was applied to soybean, peanut, and sunflower oils, and two PAEs were found in all three oils. Moreover, the method demonstrated good precision (RSD=1.17%-11.73%) and recoveries (72.49%-124.43%). Compared with other methods, the developed method was able to extract many target analytes and had a low or comparable LOD and high recovery. More importantly, this method does not require tedious operations such as solvent extraction and purification. Consequently, the developed method can be used to extract not only PAEs in oils but also other substances with a high lipid content.


Asunto(s)
Ésteres , Cromatografía de Gases y Espectrometría de Masas , Ácidos Ftálicos , Aceites de Plantas , Microextracción en Fase Sólida , Aceites de Plantas/química , Ácidos Ftálicos/análisis , Ésteres/análisis , Ésteres/química , Microextracción en Fase Sólida/métodos , Polímeros/química , Contaminación de Alimentos/análisis
10.
Materials (Basel) ; 17(15)2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39124398

RESUMEN

In this study, we successfully fabricated Fe61Zr10Co5Mo7W2B15 and Ni61Nb19.2Ta19.8 amorphous fibers (AFs) using the melt-extraction method. This method ensured a rapid cooling, uniform quality, minimal defects, and superior performance. Magnetic property analysis revealed that the Fe-based AFs exhibited a single-slope magnetization curve characteristic of paramagnetic or diamagnetic materials, while the Ni-based AFs displayed a rectangular curve with low magnetic hysteresis, typical of ferromagnetic materials. The axial saturation magnetization of as-prepared Ni-based AFs is ~1.5 × 10-7 emu/g, with a coercivity of about 85 Oe. The statistical analysis of tensile tests indicated that Ni-based AFs possess a higher fracture threshold of 2440 ± 199 MPa and a reliability of 14.7, demonstrating greater material safety and suitability for high-performance applications. As opposed to Ni-based AFs, Fe-based AFs present a fracture threshold and of 1582 ± 692 MPa and a reliability 4.2. Moreover, under cyclic loading conditions, Ni-based AFs exhibited less residual deformation and superior elastic recovery with a fracture strength of 2800 MPa. These findings highlight the potential of Ni-based AFs for advanced engineering applications, particularly where high strength, durability, and excellent magnetic properties are required, paving the way for their integration into next-generation technologies.

11.
Mater Horiz ; 11(18): 4438-4453, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-38953849

RESUMEN

Inhibiting the adhesion and growth of marine microorganisms through photocatalysis is a potentially efficient and environmentally friendly antifouling strategy. However, the undesired "shading effect" caused by resin coatings and microbial deposition reduces the utilization of the catalysts and leads to a failure in the antifouling active substance on the coating surface. Here, we successfully developed a composite coating (DPC-x) combining g-C3N4 nanosheet (g-C-NS) photocatalysts with degradable green poly-Schiff base resins, which integrates the dual functions of enhanced dynamic self-renewal and photocatalytic antibacterial activities towards long-term anti-biofouling. The controllable and complete degradability of the poly-Schiff base polymer chains and the self-renewal mechanism of the DPC-x coating exposed the internal g-C-NS, which provided a constant stream of photocatalytic reactive interfaces for 100% utilization and release of the photocatalysts. g-C-NS were homogeneously dispersed in the degradable resin coating, significantly enhancing and adjusting the self-renewal rate of the poly-Schiff base resin coating in visible light. The degradation reaction rate of DPC-0.2 (20 wt% g-C-NS) was 40 times that of DPC, thus improving the capabilities of surface self-renewal and fouling-release. Due to the synergistic antifouling mechanism of the efficient antibacterial properties and the enhanced degradation/self-renewal, the antimicrobial rates of DPC and DPC-0.2 were 94.58% and 99.31% in the dark, and 98.2% and 99.87% in visible light. DPC-x has excellent all-weather antimicrobial efficacy and could offer a new perspective on eco-friendly marine antifouling strategies.

13.
J Pharm Biomed Anal ; 248: 116332, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38964165

RESUMEN

Malondialdehyde (MDA) has long been served as a crucial indicator for assessing cellular oxidative stress levels. In this study, we introduce a new approach to determine cellular MDA levels based on a methyl tert-butyl ether (MTBE) extraction, aimed at eliminating interferences from cellular components during thiobarbituric acid (TBA) derivatization of MDA. By leveraging the effective MTBE extraction, we identified that the determination of the MDA-TBA adduct formed from the MTBE extraction layer can effectively eliminate the interferences from cellular proteins and metabolites. This method demonstrated acceptable linearity and precision in cellular samples and showed significant differences in H2O2 treated cellular oxidative stress models. The MTBE extraction-based MDA-TBA approach provides a reliable, cost-effective, and feasible method to determine cellular MDA levels using batch microplate reader approach for the assessment of cellular oxidative stress.


Asunto(s)
Peróxido de Hidrógeno , Malondialdehído , Éteres Metílicos , Estrés Oxidativo , Malondialdehído/metabolismo , Malondialdehído/análisis , Estrés Oxidativo/efectos de los fármacos , Éteres Metílicos/química , Humanos , Tiobarbitúricos/química
14.
J Colloid Interface Sci ; 674: 1004-1018, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38964000

RESUMEN

Low mechanical strength is still the key question for collagen hydrogel consisting of nanofibrils as hard tissue repair scaffolds with no loss of biological function. In this work, novel collagen nanofibrous hydrogels with high mechanical strength were fabricated based on the pre-protection of trisodium citrate masked Zr(SO4)2 solution for collagen self-assembling nanofibrils and then further coordination with Zr(SO4)2 solution. The mature collagen nanofibrils with d-period were observed in Zr(IV) mediated collagen hydrogels by AFM when the Zr(IV) concentration was ≥ 10 mmol/L, and the distribution of zirconium element was uniform. Due to the coordination of Zr(IV) with ─COOH, ─NH2 and ─OH within collagen and the tighter entanglement of collagen nanofibrils, the elastic modulus and compressive strength of Zr(IV) mediated collagen nanofibrous hydrogel were 208.3 and 1103.0 kPa, which were approximate 77 and 12 times larger than those of pure collagen hydrogel, respectively. Moreover, the environmental stability such as thermostability, swelling ability and biodegradability got outstanding improvements and could be regulated by Zr(IV) concentration. Most importantly, the resultant hydrogel showed excellent biocompatibility and even accelerated cell proliferation.


Asunto(s)
Proliferación Celular , Colágeno , Hidrogeles , Nanofibras , Circonio , Hidrogeles/química , Circonio/química , Nanofibras/química , Colágeno/química , Proliferación Celular/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Ratones , Tamaño de la Partícula , Fuerza Compresiva , Propiedades de Superficie
15.
J Sep Sci ; 47(14): e2400065, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39054584

RESUMEN

A novel zwitterionic polymer grafted silica stationary phase, Sil-PZIC, was prepared by bonding poly(ethylene maleic anhydride) molecules on the surface of silica via multiple binding sites, followed by ammonolysis of maleic anhydride through a nucleophilic substitution reaction with ethylenediamine. The stationary phase was characterized by solid-state 13C nuclear magnetic resonance, zeta potential, and elemental analysis and the results show the successful encapsulation of zwitterionic polymer on the surface of silica. The chromatographic performance of Sil-PZIC was investigated by using nucleosides and nucleic bases as test analytes The variation of retention and separation performance of these model compounds were investigated by varying the chromatographic conditions such as the components of mobile phase, salt concentration, and pH. The results show that the retention of the Sil-PZIC phase was dominated by a hydrophilic partitioning mechanism accompanied by secondary interactions such as electrostatic and hydrogen bonding. In addition, saccharides and Amadori compounds were also well separated on the Sil-PZIC, indicating that the Sil-PZIC column has potential application for separation of the polar compound.

16.
Sci Bull (Beijing) ; 69(18): 2930-2937, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-38926060

RESUMEN

The scarcity of proxies and calibration models for quantitatively reconstructing millennial timescale seasonal temperature tremendously constraints our understanding of the Holocene thermal variation and its driven mechanisms. Here, we established two global warm-season temperature models by applying deep learning neural network analysis to the branched tetraether membrane lipids originating from surface soil and lacustrine sediment bacteria. We utilized these optimal models in global well-dated lacustrine, peatland, and loess profiles covering the Holocene. All reconstructions of warm-season temperatures, consistent with climate model simulations, indicate cooling trends since the early Holocene, primarily induced by decreased solar radiation in the Northern Hemisphere due to the precession peak at the early. We further demonstrated that the membrane lipids can effectively enhance the future millennial seasonal temperature research, including winter temperatures, without being restricted by geographical location and sedimentary carrier.

17.
Biochem Pharmacol ; 226: 116381, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38909786

RESUMEN

The escalating prevalence of obesity presents formidable challenges, necessitating the development of effective therapeutic strategies. In this study, we aimed to elucidate the preventive effects on obesity of tetrahydroberberrubine (THBru), a derivative of berberine (BBR) and to unravel its underlying mechanism. Using an obese mouse model induced by a high-fat diet (HFD), THBru was found to markedly ameliorate obesity, as evidenced by reduced body weight, decreased Lee's index, diminished fat mass in epididymal white adipose tissue (WAT) and brown adipose tissue (BAT), alongside improved dyslipidemia. Notably, at the same dose, THBru exhibited superior efficacy compared to BBR. RNA-sequencing and gene set enrichment analysis indicated THBru activated thermogenesis, which was further confirmed in WAT, BAT, and 3T3-L1 cells. Bioinformatics analysis of RNA-sequencing data revealed the candidate gene Pgc1α, a key regulator involved in thermogenesis. Moreover, THBru was demonstrated to elevate the expression of PGC1α by stabilizing its mRNA in WAT, BAT and 3T3-L1 cells. Furthermore, PGC1α knockdown blocked the pro-thermogenic and anti-obesity action of THBru both in vivo and in vitro. This study unravels the preventive effects of THBru on obesity through the activation of PGC1α-mediated thermogenesis, thereby delineating its potential therapeutic implications for obesity and associated disorders.


Asunto(s)
Células 3T3-L1 , Tejido Adiposo Pardo , Tejido Adiposo Blanco , Berberina , Dieta Alta en Grasa , Ratones Endogámicos C57BL , Obesidad , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Termogénesis , Animales , Termogénesis/efectos de los fármacos , Ratones , Tejido Adiposo Pardo/efectos de los fármacos , Tejido Adiposo Pardo/metabolismo , Masculino , Berberina/farmacología , Berberina/análogos & derivados , Berberina/uso terapéutico , Obesidad/prevención & control , Obesidad/metabolismo , Obesidad/tratamiento farmacológico , Tejido Adiposo Blanco/efectos de los fármacos , Tejido Adiposo Blanco/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Dieta Alta en Grasa/efectos adversos , Fármacos Antiobesidad/farmacología
18.
J Colloid Interface Sci ; 674: 603-611, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38945027

RESUMEN

Rechargeable magnesium battery is regarded as the promising candidate for the next generation of high-specific-energy storage systems. Nevertheless, issues related to severe Mg-Cl dissociation at the electrolyte-electrode interface impede the insertion of Mg2+ into most materials, leading to severe polarization and low utilization of Mg-storage electrodes. In this study, a metal-organic polymer (MOP) Ni-TABQ (Ni-coordinated tetramino-benzoquinone) with superior surface catalytic activity is proposed to achieve the high-capacity Mg-MOP battery. The layered Ni-TABQ cathode, featuring a unique 2D π-d linear conjugated structure, effectively reduces the dissociation energy of MgxCly clusters at the Janus interface, thereby facilitating Mg2+ insertion. Due to the high utilization of active sites, Ni-TABQ achieves high capacities of 410 mAh/g at 200 mA g-1, attributable to a four-electron redox process involving two redox centers, benzoid carbonyls, and imines. This research highlights the importance of surface electrochemical processes in rechargeable magnesium batteries and paves the way for future development in multivalent metal-ion batteries.

19.
Viruses ; 16(5)2024 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-38793641

RESUMEN

Acinetobacter baumannii has developed multiple drug resistances, posing a significant threat to antibiotic efficacy. LysECD7, an endolysin derived from phages, could be a promising therapeutic agent against multi-drug resistance A. baumannii. In this study, in order to further enhance the antibacterial efficiency of the engineered LysECD7, a few lipopolysaccharide-interacting peptides (Li5, MSI594 and Li5-MSI) were genetically fused with LysECD7. Based on in vitro antibacterial activity, the fusion protein Lys-Li5-MSI was selected for further modifications aimed at extending its half-life. A cysteine residue was introduced into Lys-Li5-MSI through mutation (Lys-Li5-MSIV12C), followed by conjugation with a C16 fatty acid chain via a protonation substitution reaction(V12C-C16). The pharmacokinetic profile of V12C-C16 exhibited a more favorable characteristic in comparison to Lys-Li5-MSI, thereby resulting in enhanced therapeutic efficacy against lethal A. baumannii infection in mice. The study provides valuable insights for the development of novel endolysin therapeutics and proposes an alternative therapeutic strategy for combating A. baumannii infections.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Antibacterianos , Endopeptidasas , Lipopolisacáridos , Proteínas Recombinantes de Fusión , Animales , Femenino , Ratones , Acinetobacter baumannii/efectos de los fármacos , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/microbiología , Antibacterianos/farmacología , Antibacterianos/química , Modelos Animales de Enfermedad , Endopeptidasas/farmacología , Endopeptidasas/metabolismo , Endopeptidasas/química , Endopeptidasas/genética , Ácidos Grasos/metabolismo , Ácidos Grasos/química , Ácidos Grasos/farmacología , Lipopolisacáridos/metabolismo , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Péptidos/farmacología , Péptidos/química , Proteínas Recombinantes de Fusión/farmacología , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/química
20.
IEEE J Biomed Health Inform ; 28(9): 5447-5458, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38805334

RESUMEN

Nasopharyngeal carcinoma (NPC) is a malignant tumor primarily treated by radiotherapy. Accurate delineation of the target tumor is essential for improving the effectiveness of radiotherapy. However, the segmentation performance of current models is unsatisfactory due to poor boundaries, large-scale tumor volume variation, and the labor-intensive nature of manual delineation for radiotherapy. In this paper, MMCA-Net, a novel segmentation network for NPC using PET/CT images that incorporates an innovative multimodal cross attention transformer (MCA-Transformer) and a modified U-Net architecture, is introduced to enhance modal fusion by leveraging cross-attention mechanisms between CT and PET data. Our method, tested against ten algorithms via fivefold cross-validation on samples from Sun Yat-sen University Cancer Center and the public HECKTOR dataset, consistently topped all four evaluation metrics with average Dice similarity coefficients of 0.815 and 0.7944, respectively. Furthermore, ablation experiments were conducted to demonstrate the superiority of our method over multiple baseline and variant techniques. The proposed method has promising potential for application in other tasks.


Asunto(s)
Algoritmos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Carcinoma Nasofaríngeo/diagnóstico por imagen , Neoplasias Nasofaríngeas/diagnóstico por imagen , Imagen de Cuerpo Entero/métodos , Redes Neurales de la Computación
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