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1.
J Agric Food Chem ; 72(19): 11251-11258, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38699857

RESUMEN

Engineered nanoparticles (ENPs) have been increasingly used in agricultural operations, leading to an urgent need for robust methods to analyze co-occurring ENPs in plant tissues. In response, this study advanced the simultaneous extraction of coexisting silver, cerium oxide, and copper oxide ENPs in lettuce shoots and roots using macerozyme R-10 and analyzed them by single-particle inductively coupled plasma-mass spectrometry (ICP-MS). Additionally, the standard stock suspensions of the ENPs were stabilized with citrate, and the long-term stability (up to 5 months) was examined for the first time. The method performance results displayed satisfactory accuracies and precisions and achieved low particle concentration and particle size detection limits. Significantly, the oven drying process was proved not to impact the properties of the ENPs; therefore, oven-dried lettuce tissues were used in this study, which markedly expanded the applicability of this method. This robust methodology provides a timely approach to characterize and quantify multiple coexisting ENPs in plants.


Asunto(s)
Lactuca , Espectrometría de Masas , Nanopartículas del Metal , Raíces de Plantas , Nanopartículas del Metal/química , Lactuca/química , Espectrometría de Masas/métodos , Raíces de Plantas/química , Cobre/análisis , Brotes de la Planta/química , Plata/química , Cerio/química , Tamaño de la Partícula
2.
PLoS One ; 19(5): e0282173, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38768257

RESUMEN

This paper employs a unique data set to analyze the trading behavior of wealthy individual investors across Mainland China and their impact on Chinese stock markets' tail risk. Results show that the wealthy individual investors' trading behavior can explain Chinese stock markets' tail risk, and the daily investment portfolios based on the network density of wealthy individual investors have significant excess returns. This paper also investigates the determinants of wealthy individual investors' trading behavior with the social network method and the spatial econometric model, and reveals that wealthy individuals benefit from the spillover effect of their trading behavior through the investor networks. The results of this paper not only reveal micro evidence for the formation mechanism of asset prices, but also provide insight into the behavior of wealthy individual investors.


Asunto(s)
Inversiones en Salud , Inversiones en Salud/economía , China , Humanos , Modelos Económicos , Comercio/economía , Modelos Econométricos
3.
Insect Sci ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769889

RESUMEN

Disruption of the circadian clock can affect starvation resistance, but the molecular mechanism is still unclear. Here, we found that starvation resistance was significantly reduced in the core gene BmPer deficient mutant silkworms (Per-/-), but the mutant's starvation resistance increased with larval age. Under natural physiological conditions, the weight of mutant 5th instar larvae was significantly increased compared to wild type, and the accumulation ability of triglycerides and glycogen in the fat bodies was upregulated. However, under starvation conditions, the weight consumption of mutant larvae was increased and cholesterol utilization was intensified. Transcriptome analysis showed that beta-oxidation was significantly upregulated under starvation conditions, fatty acid synthesis was inhibited, and the expression levels of genes related to mitochondrial function were significantly changed. Further investigations revealed that the redox balance, which is closely related to mitochondrial metabolism, was altered in the fat bodies, the antioxidant level was increased, and the pentose phosphate pathway, the source of reducing power in cells, was activated. Our findings suggest that one of the reasons for the increased energy burden observed in mutants is the need to maintain a more robust redox balance in metabolic tissues. This necessitates the diversion of more glucose into the pentose phosphate pathway to ensure an adequate supply of reducing power.

4.
ACS Pharmacol Transl Sci ; 7(5): 1612-1623, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38751634

RESUMEN

Polyriboinosinic acid-polyribocytidylic acid (Poly I:C) serves as a synthetic mimic of viral double-stranded dsRNA, capable of inducing apoptosis in numerous cancer cells. Despite its potential, therapeutic benefits, the application of Poly I:C has been hindered by concerns regarding toxicity, stability, enzymatic degradation, and undue immune stimulation, leading to autoimmune disorders. To address these challenges, encapsulation of antitumor drugs within delivery systems such as cationic liposomes is often employed to enhance their efficacy while minimizing dosages. In this study, we investigated the potential of cationic liposomes to deliver Poly I:C into the Head and Neck 12 (HN12) cell line to induce apoptosis in the carcinoma cells and tumor model. Cationic liposomes made by the hydrodynamic focusing method surpass traditional methods by offering a continuous flow-based approach for encapsulating genes, which is ideal for efficient tumor delivery. DOTAP liposomes efficiently bind Poly I:C, confirmed by transmission electron microscopy images displaying their spherical morphology. Liposomes are easily endocytosed in HN12 cells, suggesting their potential for therapeutic gene and drug delivery in head and neck squamous carcinoma cells. Activation of apoptotic pathways involving MDA5, RIG-I, and TLR3 is evidenced by upregulated caspase-3, caspase-8, and IRF3 genes upon endocytosis of Poly(I:C)-encapsulated liposomes. Therapeutic evaluations revealed significant inhibition of tumor growth with Poly I:C liposomes, indicating the possibility of MDA5, RIG-I, and TLR3-induced apoptosis pathways via Poly I:C liposomes in HN12 xenografts in J:NU mouse models. Comparative histological analysis underscores enhanced cell death with Poly I:C liposomes, warranting further investigation into the precise mechanisms of apoptosis and inflammatory cytokine response in murine models for future research.

5.
J Asian Nat Prod Res ; : 1-10, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753580

RESUMEN

Nine jatrophane diterpenoids were isolated from the whole plant Euphorbia helioscopia, including two new ones, helioscopnins A (1) and B (2). Comprehensive spectroscopic data analysis and ECD calculations elucidated their structures, including absolute configurations. All compounds were evaluated for bioactivity towards autophagic flux by flow cytometry using HM mCherry-GFP-LC3 cells. Compounds 1, 3, 4, 5, 8, and 9 significantly increased autophagic flux.

6.
Biomacromolecules ; 25(5): 2770-2779, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38687975

RESUMEN

Drug repurposing uses approved drugs as candidate anticancer therapeutics, harnesses previous research and development efforts, and benefits from available clinically suitable formulations and evidence of patient tolerability. In this work, the drug used clinically to treat chronic alcoholism, disulfiram (DSF), was studied for its antitumor efficacy in a copper-dependent manner. The combination of DSF and copper could achieve a tumor cell growth inhibition effect comparable to those of 5-fluorouracil and taxol on head and neck cancer cells. Both bulk dendrimer hydrogel and microsized dendrimer hydrogel particles were utilized for the localized sustained release of copper in the tumor site. The localized sustained release of copper facilitated the tumor inhibition effect following intratumoral injection in a mouse's head and neck cancer model.


Asunto(s)
Cobre , Preparaciones de Acción Retardada , Disulfiram , Neoplasias de Cabeza y Cuello , Disulfiram/farmacología , Disulfiram/química , Disulfiram/administración & dosificación , Animales , Cobre/química , Cobre/farmacología , Ratones , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/patología , Humanos , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacología , Línea Celular Tumoral , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/administración & dosificación , Ensayos Antitumor por Modelo de Xenoinjerto , Ratones Desnudos
7.
Clin Neurol Neurosurg ; 240: 108250, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38552364

RESUMEN

Hypoxia is a prevalent characteristic of numerous neurological disorders including stroke, Alzheimer's disease, and Parkinson's disease. Extracellular vesicles (EVs) are minute particles released by cells that contain diverse biological materials, including proteins, lipids, and nucleic acids. They have been implicated in a range of physiological and pathological processes including intercellular communication, immune responses, and disease progression. EVs are believed to play a pivotal role in modulating the microenvironment of hypoxia-associated neurological diseases. These EVs are capable of transporting hypoxia-inducible factors such as proteins and microRNAs to neighboring or remote cells, thereby influencing their behavior. Furthermore, EVs can traverse the blood-brain barrier, shielding the brain from detrimental substances in the bloodstream. This enables them to deliver their payload directly to the brain cells, potentially intensifying the effects of hypoxia. Nonetheless, the capacity of EVs to breach the blood-brain barrier presents new opportunities for drug delivery. The objective of this study was to elucidate the role of EVs as mediators of information exchange during tissue hypoxia, a pathophysiological process in ischemic stroke and malignant gliomas. We also investigated their involvement in the progression and regression of major diseases of the central nervous system, which are pertinent to the development of therapeutic interventions for neurological disorders.


Asunto(s)
Vesículas Extracelulares , Humanos , Vesículas Extracelulares/metabolismo , Enfermedades del Sistema Nervioso/etiología , Enfermedades del Sistema Nervioso/metabolismo , Hipoxia/metabolismo , Barrera Hematoencefálica/metabolismo , Animales
8.
Int J Mol Sci ; 25(5)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38473752

RESUMEN

Gliomas represent the most common and lethal category of primary brain tumors. Bisphenol A (BPA), a widely recognized endocrine disruptor, has been implicated in the progression of cancer. Despite its established links to various cancers, the association between BPA and glioma progression remains to be clearly defined. This study aimed to shed light on the impact of BPA on glioma cell proliferation and overall tumor progression. Our results demonstrate that BPA significantly accelerates glioma cell proliferation in a time- and dose-dependent manner. Furthermore, BPA has been found to enhance the invasive and migratory capabilities of glioma cells, potentially promoting epithelial-mesenchymal transition (EMT) characteristics within these tumors. Employing bioinformatics approaches, we devised a risk assessment model to gauge the potential glioma hazards associated with BPA exposure. Our comprehensive analysis revealed that BPA not only facilitates glioma invasion and migration but also inhibits apoptotic processes. In summary, our study offers valuable insights into the mechanisms by which BPA may promote tumorigenesis in gliomas, contributing to the understanding of its broader implications in oncology.


Asunto(s)
Glioma , Humanos , Línea Celular Tumoral , Compuestos de Bencidrilo/farmacología , Fenoles/farmacología
9.
Front Endocrinol (Lausanne) ; 15: 1291895, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38419954

RESUMEN

Introduction: The ratio of Triglyceride (TG) to high-density lipoprotein cholesterol (HDL-C) is a crucial indicator for diabetes diagnosis. Methods: This study utilizes the Copula function to model and fit the non-linear correlation among fasting blood glucose (Glu), glycosylated hemoglobin (HbA1C), and TG/HDL-C in patients with diabetes. The Copula function chosen for this study includes the two-dimensional Archimedes and Elliptical distribution family, as well as the multidimensional Vine Copula function, for fitting the data. The evaluation of the fitting effect is performed using the mean absolute error (MAE) and mean square error (MSE). Results: The results indicate that the Clayton Copula exhibits the highest effectiveness in fitting the pairwise relationship between Glu and TG/HDL-C, as well as HbA1C and TG/HDL-C, displaying the smallest fitting error. Additionally, the Vine Copula function produces a satisfactory fit for the relationship among all three indicators. Compared to linear analysis methods, the Copula function more accurately depicts the correlation among these three types of indicators. Discussion: Moreover, our findings indicate a stronger correlation in the lower tail between Glu and HbA1C, as well as TG/HDL-C, suggesting that the Copula function provides greater accuracy and applicability in depicting the relationship among these indicators. As a result, it can offer a more precise auxiliary diagnosis and serve as a valuable reference in clinical judgment.


Asunto(s)
Glucemia , Diabetes Mellitus , Humanos , Hemoglobina Glucada , Diabetes Mellitus/diagnóstico , Triglicéridos , HDL-Colesterol
10.
Heliyon ; 10(2): e24795, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38304798

RESUMEN

Most clinically non-functioning pituitary tumour arise from gonadotroph cells. However, clinically functional pituitary gonadotroph adenoma is rare. Here we report a female case who presented with menstrual disturbances, however further workup demonstrated a pituitary microadenoma with elevated FSH and oestradiol level. Transsphenoidal resection was performed and the surgical histopathology confirmed pituitary gonadotroph adenoma. Postoperatively, improvement in both symptoms and hormonal profile were observed. Interestingly, the initially enlarged and polycystic ovaries became within normal range around eight months after the surgery. We suggest functional gonadotroph adenoma should be considered in the presence of gynaecological disorder with persistently elevated oestradiol and FSH levels.

11.
Respir Res ; 25(1): 72, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38317180

RESUMEN

BACKGROUND: Pneumocystis pneumonia (PCP) is a life-threatening opportunistic fungal infection with a high mortality rate in immunocompromised patients, ranging from 20 to 80%. However, current understanding of the variation in host immune response against Pneumocystis across different timepoints is limited. METHODS: In this study, we conducted a time-resolved single-cell RNA sequencing analysis of CD45+ cells sorted from lung tissues of mice infected with Pneumocystis. The dynamically changes of the number, transcriptome and interaction of multiply immune cell subsets in the process of Pneumocystis pneumonia were identified according to bioinformatic analysis. Then, the accumulation of Trem2hi interstitial macrophages after Pneumocystis infection was verified by flow cytometry and immunofluorescence. We also investigate the role of Trem2 in resolving the Pneumocystis infection by depletion of Trem2 in mouse models. RESULTS: Our results characterized the CD45+ cell composition of lung in mice infected with Pneumocystis from 0 to 5 weeks, which revealed a dramatic reconstitution of myeloid compartments and an emergence of PCP-associated macrophage (PAM) following Pneumocystis infection. PAM was marked by the high expression of Trem2. We also predicted that PAMs were differentiated from Ly6C+ monocytes and interacted with effector CD4+ T cell subsets via multiple ligand and receptor pairs. Furthermore, we determine the surface markers of PAMs and validated the presence and expansion of Trem2hi interstitial macrophages in PCP by flow cytometry. PAMs secreted abundant pro-inflammation cytokines, including IL-6, TNF-α, GM-CSF, and IP-10. Moreover, PAMs inhibited the proliferation of T cells, and depletion of Trem2 in mouse lead to reduced fungal burden and decreased lung injury in PCP. CONCLUSION: Our study delineated the dynamic transcriptional changes in immune cells and suggests a role for PAMs in PCP, providing a framework for further investigation into PCP's cellular and molecular basis, which could provide a resource for further discovery of novel therapeutic targets.


Asunto(s)
Glicoproteínas de Membrana , Neumonía por Pneumocystis , Receptores Inmunológicos , Animales , Ratones , Inmunidad , Inflamación/metabolismo , Pulmón/microbiología , Macrófagos/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Neumonía por Pneumocystis/genética , Receptores Inmunológicos/genética , Receptores Inmunológicos/metabolismo
12.
J Econ Entomol ; 117(2): 388-400, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38266252

RESUMEN

Artificial diets for silkworms overcome the seasonal limitations of traditional rearing methods with fresh mulberry leaves. However, the current wet artificial diets, steamed at high temperatures, are not favored by silkworms, and they are cumbersome and challenging to preserve. These conditions adversely affected the development of artificial diet-based sericulture production. In this study, we disinfected dry powder diets with radiation and added distilled water without steaming before use. Then, the nutritional value of finished diets and their impact on silkworm development was assessed. Compared with steamed diets, nonsteamed diets were more attractive to silkworms. Chemical assays showed significantly more essential nutrients for silkworms, including l-ascorbic acid, vitamin B1, vitamin B2, and urease in nonsteamed diets than in steamed diets. Feeding fifth-instar silkworm larvae with nonsteamed diets significantly improved the ammonia utilization efficiency of the diet and increased the cocoon shell rate and diet/silk protein conversion efficiency by 5.9% and 13.3%, respectively. When fed with nonsteamed diets, the abundance of aerobic microorganisms in silkworm intestines increased and the abundance of pathogenic bacteria decreased. Furthermore, the vitality of the silkworm, measured by the dead worm cocoon rate, significantly improved by 16.90%. In summary, preparing sterile wet diets without high-temperature steaming effectively improved the nutritional value of the diet and enhanced silkworm growth.


Asunto(s)
Bombyx , Morus , Animales , Seda/metabolismo , Dieta , Larva , Valor Nutritivo
13.
ACS Biomater Sci Eng ; 10(2): 697-722, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38241003

RESUMEN

Cancer theranostics developed through nanoengineering applications are essential for targeted oncologic interventions in the new era of personalized and precision medicine. Recently, small extracellular vesicles (sEVs) have emerged as an attractive nanoengineering platform for tumor-directed anticancer therapeutic delivery and imaging of malignant tumors. These natural nanoparticles have multiple advantages over synthetic nanoparticle-based delivery systems, such as intrinsic targeting ability, less immunogenicity, and a prolonged circulation time. Since the inception of sEVs as a viable replacement for liposomes (synthetic nanoparticles) as a drug delivery vehicle, many studies have attempted to further the therapeutic efficacy of sEVs. This article discusses engineering strategies for sEVs using physical and chemical methods to enhance their anticancer therapeutic delivery performance. We review physio-chemical techniques of effective therapeutic loading into sEV, sEV surface engineering for targeted entry of therapeutics, and its cancer environment sensitive release inside the cells/organ. Next, we also discuss the novel hybrid sEV systems developed by a combination of sEVs with lipid and metal nanoparticles to garner each component's benefits while overcoming their drawbacks. The article extensively analyzes multiple sEV labeling techniques developed and investigated for live tracking or imaging sEVs. Finally, we discuss the theranostic potential of engineered sEVs in future cancer care regimens.


Asunto(s)
Vesículas Extracelulares , Nanopartículas del Metal , Medicina de Precisión , Sistemas de Liberación de Medicamentos , Ingeniería
14.
J Clin Invest ; 134(3)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38015641

RESUMEN

Pulmonary arterial hypertension (PAH) is a devastating and progressive disease with limited treatment options. Endothelial dysfunction plays a central role in the development and progression of PAH, yet the underlying mechanisms are incompletely understood. The endosome-lysosome system is important to maintain cellular health, and the small GTPase RAB7 regulates many functions of this system. Here, we explored the role of RAB7 in endothelial cell (EC) function and lung vascular homeostasis. We found reduced expression of RAB7 in ECs from patients with PAH. Endothelial haploinsufficiency of RAB7 caused spontaneous pulmonary hypertension (PH) in mice. Silencing of RAB7 in ECs induced broad changes in gene expression revealed via RNA-Seq, and RAB7-silenced ECs showed impaired angiogenesis and expansion of a senescent cell fraction, combined with impaired endolysosomal trafficking and degradation, suggesting inhibition of autophagy at the predegradation level. Furthermore, mitochondrial membrane potential and oxidative phosphorylation were decreased, and glycolysis was enhanced. Treatment with the RAB7 activator ML-098 reduced established PH in rats with chronic hypoxia/SU5416. In conclusion, we demonstrate for the first time to our knowledge the fundamental impairment of EC function by loss of RAB7, causing PH, and show RAB7 activation to be a potential therapeutic strategy in a preclinical model of PH.


Asunto(s)
Hipertensión Pulmonar , Animales , Humanos , Ratones , Ratas , Hipertensión Pulmonar Primaria Familiar/metabolismo , Hipertensión Pulmonar/etiología , Hipoxia/metabolismo , Pulmón/metabolismo , Arteria Pulmonar/metabolismo
15.
Anal Bioanal Chem ; 416(2): 419-430, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37962610

RESUMEN

Legionella pneumophila is a persistent opportunistic pathogen that poses a significant threat to domestic water systems. Previous studies suggest that copper (Cu) is an effective antimicrobial in water systems. A rapid and sensitive quantification method is desired to optimize the conditions of L. pneumophila treatment by Cu and to better understand the interaction mechanisms between Cu and cells. In this study, we developed a highly sensitive single cell (SC)-ICP-MS method to monitor L. pneumophila cell concentration and track their uptake of Cu. The SC-ICP-MS method showed excellent sensitivity (with a cell concentration detection limit of 1000 cells/mL), accuracy (good agreement with conventional hemocytometry method), and precision (relative standard deviation < 5%) in drinking water matrix. The cupric ions (Cu2+) treatment results indicated that the total L. pneumophila cell concentration, Cu mass per cell, colony-forming unit counting, and Cu concentration in supernatant all exhibited a dose-dependent trend, with 800-1200 µg/L reaching high disinfection rates in drinking water. The investigation of percentages of viable and culturable, viable but nonculturable (VBNC), and lysed cells suggested there always were VBNC present at any Cu concentration. Experimental results of different Cu2+ treatment times further suggested that L. pneumophila cells developed an antimicrobial resistant mechanism with the prolonged Cu exposure. This is the first quantification study on the interactions of Cu and L. pneumophila in drinking water using SC-ICP-MS.


Asunto(s)
Antiinfecciosos , Agua Potable , Legionella pneumophila , Abastecimiento de Agua , Cobre , Microbiología del Agua
16.
Haemophilia ; 30(1): 195-203, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38058260

RESUMEN

AIM: Haemophiliac arthritis (HA) is caused by spontaneous intra-articular hemorrhage and repeated intra-articular hematomas, leading to iron overload, which, in turn, induces M1 macrophage polarisation and inflammatory cytokine secretion, resulting in synovitis. Here, we explored the mechanism by which iron overload in HA induces the polarisation of M1 macrophages, providing a new approach for the treatment of HA synovitis. METHODS: The synovium from the knee joints of normal amputees and patients with HA was collected. Pathological changes in the synovial tissues were analysed using hematoxylin and eosin staining. Iron tissue deposition was evaluated using the iron assay kit and Prussia Blue staining, while macrophage phenotype was determined using immunofluorescence. The levels of pro-inflammatory cytokines and p53 acetylation were determine using western blotting. An in vitro iron overload model was established by inducing THP-1 macrophages with ferric ammonium citrate, and the involvement of acetylated p53 in M1 macrophage polarisation was investigated. RESULTS: Compared to control samples, the iron content in the synovium of patients with HA was significantly increased. The protein levels of M1 macrophage markers, pro-inflammatory cytokines, and acetylated p53, were also significantly elevated in the synovial tissues of patients with HA. Similar results were observed in the in vitro iron overload model. Furthermore, the inhibition of p53 acetylation in vitro reversed these iron overload-induced effects. CONCLUSION: In patients with HA, iron overload induced synovial p53 acetylation, leading to macrophage polarisation toward the M1 phenotype and increased inflammatory cytokine secretion, resulting in synovitis. HIGHLIGHTS: Synovial iron overload is associated with changes in P53 acetylation in hemophiliac arthritis (HA). Acetylated p53, a known regulator of macrophage polarization, is highly expressed in HA synovium, suggesting a potential role in M1 polarization. HA synovial macrophages predominantly polarize into the pro-inflammatory M1 phenotype, secreting elevated levels of pro-inflammatory cytokines.


Asunto(s)
Sobrecarga de Hierro , Osteoartritis , Sinovitis , Humanos , Proteína p53 Supresora de Tumor/metabolismo , Membrana Sinovial/patología , Macrófagos/metabolismo , Macrófagos/patología , Sinovitis/complicaciones , Osteoartritis/patología , Fenotipo , Sobrecarga de Hierro/complicaciones , Sobrecarga de Hierro/metabolismo , Sobrecarga de Hierro/patología , Hierro/metabolismo , Citocinas/metabolismo
17.
Small ; 20(13): e2306863, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37963848

RESUMEN

The construction of stable copper nanoclusters (Cu-NCs) with near-infrared (NIR) emission that can be used for catalysis is highly desired, yet remains a challenge. Herein, an atomically precise bimetallic Cu/Pd NC with a molecular formula of Cu16Pd1L10(PPh3)2(Pz)6 (Pz = 3,5-(CF3)2Pyrazolate, L = 4-CH3OPhC≡C-), abbreviated as Cu16Pd1, is synthesized. Single-crystal X-ray crystallographic analysis of Cu16Pd1 reveals a Cu10Pd1 kernel with pseudo-gyroelongated square bipyramid confirmation surrounded by other 6 Cu(I) ions and protected ligands. Interestingly, it exhibits strong NIR emission with the highest photoluminescence quantum yield (PLQY) among all the Cu NCs/Cu alloys (λem > 800 nm) in the solid-state, and also displays NIR emission in solution. Experimental results and theoretical calculations suggest that the impressive NIR emission is attributed to abundant supramolecular interactions in the solid-state, including intramolecular metal-metal and intermolecular interactions. Of note, the bimetallic Cu16Pd1 can catalyze the reduction of 4-nitrophenol. This work provides a novel method for synthesizing Cu/Pd NCs and reminds that the less studied Cu/Pd NC can serve as outstanding luminescent material, which is seldom noticed in atomically precise nanoclusters.

18.
Int J Biol Macromol ; 254(Pt 3): 127950, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37951431

RESUMEN

Chitosan has great potential for biomedical applications. However, the intractable solubility of chitosan is a major bottleneck hampering its utilization. In this work, we report a low-temperature solvent-exchange method to solubilize chitosan in biologically relevant solvents (bio-solvents) including water, salines, and cell culture media. Chitosan was firstly dissolved in ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate (EMIM Ac). The chitosan/IL solution was then dialyzed against bio-solvents at 4 °C, during which a solvent exchange process took place. At the end of 24 h dialysis, aqueous chitosan pseudosolutions formed. Low temperature is found to be crucial for efficient solubilization of chitosan during the solvent exchange process. Increasing temperature to 50 °C leads to the formation of solid chitosan hydrogel. Chitosan in the water-based pseudosolution presents as positively charged particles. The pseudosolution shows a high positive zeta potential of about +52.6 mV and good colloidal stability. The water-based pseudosolutions with different amounts of chitosan contents exhibit the rheological features of weak liquid gels. By using these pseudosolutions, the fabrication of various chitosan materials is realized readily. Both chitosan pseudosolution and its downstream products are highly biocompatible. In this strategy, using IL as a solvent-medium and processing a low-temperature solvent exchange are the two key parameters to solubilize chitosan.


Asunto(s)
Quitosano , Líquidos Iónicos , Solventes , Materiales Biocompatibles , Temperatura , Diálisis Renal , Agua
19.
Sci Total Environ ; 912: 168740, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38013102

RESUMEN

In this work, a novel double-network composite hydrogel (SA/TA), composed of sodium alginate (SA) and tannic acid (TA), was designed and fabricated by a successive cross-linking method using Ti(IV) and Ca(II) as crosslinkers. SA/TA exhibited reinforced mechanical strength and anti-swelling properties because of the double-network structure. SA/TA was used as an adsorbent for removal of a popular antiviral drug, chloroquine phosphate (CQ), in water. The adsorption performance of SA/TA was systematically investigated, to study various effects including those of TA mass content, solution pH, adsorption time, and initial CQ concentration. Adsorption was also examined in presence of inorganic and organic coexisting substances commonly found in wastewater, and under different actual water samples. Batch experimental results indicated that SA/TA could maintain higher and more stable CQ uptakes within a wide solution pH range from 3.0 to 10.0, compared to its precursor, SA hydrogel, owing to the addition of TA-Ti(IV) coordination network. The maximum experimental CQ uptake exhibited by the 1:1 (by wt) SA/TA (SA/TA2) was as high as 0.699 mmol/g at the initial pH of 9.0. A high concentration of coexisting NaCl evidently reduced the CQ uptakes of SA/TA2 due to the electrostatic shielding effect, moreover, divalent cations including Ca(II) and Mg(II) also inhibited the adsorption of CQ due to competitive adsorption. However, humic acid had little effect on this adsorption. Considering the apparent adsorption performance, the aforementioned effects of various factors and the spectroscopic characterizations, multi-interactions are suggested for adsorption including chelation, electrostatic interactions, π-π electron donor-acceptor interaction and hydrogen bonding. SA/TA showed a slight loss in adsorption capacity toward CQ and sustained physicochemical structural stability, even after six adsorption-desorption cycles. In addition to CQ, SA/TA could be efficiently used for adsorption of two other antivirus drugs, namely, hydroxychloroquine sulfate and oseltamivir phosphate. This work provides an effective strategy for the design and fabrication of novel adsorbents that can effectively adsorb antiviral drugs over a wide pH range.


Asunto(s)
Cloroquina/análogos & derivados , Hidrogeles , Polifenoles , Contaminantes Químicos del Agua , Hidrogeles/química , Adsorción , Alginatos/química , Agua , Concentración de Iones de Hidrógeno , Cinética , Contaminantes Químicos del Agua/análisis
20.
Exp Eye Res ; 238: 109723, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37979905

RESUMEN

Aniridia is a panocular condition characterized by a partial or complete loss of the iris. It manifests various developmental deficits in both the anterior and posterior segments of the eye, leading to a progressive vision loss. The homeobox gene PAX6 plays an important role in ocular development and mutations of PAX6 have been the main causative factors for aniridia. In this study, we assessed how Pax6-haploinsufficiency affects retinal morphology and vision of Pax6Sey mice using in vivo and ex vivo metrics. We used mice of C57BL/6 and 129S1/Svlmj genetic backgrounds to examine the variable severity of symptoms as reflected in human aniridia patients. Elevated intraocular pressure (IOP) was observed in Pax6Sey mice starting from post-natal day 20 (P20). Correspondingly, visual acuity showed a steady age-dependent decline in Pax6Sey mice, though these phenotypes were less severe in the 129S1/Svlmj mice. Local retinal damage with layer disorganization was assessed at P30 and P80 in the Pax6Sey mice. Interestingly, we also observed a greater number of activated Iba1+ microglia and GFAP + astrocytes in the Pax6Sey mice than in littermate controls, suggesting a possible neuroinflammatory response to Pax6 deficiencies.


Asunto(s)
Aniridia , Microftalmía , Humanos , Ratones , Animales , Factor de Transcripción PAX6/genética , Factores de Transcripción Paired Box/genética , Enfermedades Neuroinflamatorias , Ratones Endogámicos C57BL , Microftalmía/genética , Aniridia/genética , Proteínas de Homeodominio/genética , Proteínas del Ojo/genética
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