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1.
Talanta ; 275: 126127, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38663073

RESUMO

Modified electrosynthetic sample introduction technique is a reliable means of solving the problem of high sensitivity analysis of trace arsenite. This article attempts to achieve selective electroreduction of AsIII through the construction of electrode surfaces with different structures and materials from the perspective of interface reactions. Among the four transition metal modifiers, the iron modified nickel foam electrode with nano-flower structure documented higher efficiency in inducing arsenic reduction and better species selectivity. Systematic electrochemical and spectroscopic tests suggest that strong adsorption effect between Fe and AsIII, appropriate hydrogen evolution potential, and catalytic activity jointly promote efficient electroreduction of AsIII. Optimization based on electrode materials and electrolysis conditions, with high sensitivity, wide linear range (0.1-50 µg L-1), and excellent species selectivity, this paper offers an efficient and economic sample introduction method for trace AsIII/V selective atomic spectroscopy direct determination.

2.
Eur J Med Chem ; 268: 116300, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38452729

RESUMO

Sepsis is a systemic inflammatory response syndrome caused by an infection. Toll-like receptor 4 (TLR4) is activated by endogenous molecules released by injured or necrotic tissues. Additionally, TLR4 is remarkably sensitive to infection of various bacteria and can rapidly stimulate host defense responses. The TLR4 signaling pathway plays an important role in sepsis by activating the inflammatory response. Accordingly, as part of efforts to improve the inflammatory response and survival rate of patients with sepsis, several drugs have been developed to regulate the inflammatory signaling pathways mediated by TLR4. Inhibition of TLR4 signal transduction can be directed toward either TLR4 directly or other proteins in the TLR4 signaling pathway. Here, we review the advances in the development of small-molecule agents and peptides targeting regulation of the TLR4 signaling pathway, which are characterized according to their structural characteristics as polyphenols, terpenoids, steroids, antibiotics, anthraquinones, inorganic compounds, and others. Therefore, regulating the expression of the TLR4 signaling pathway and modulating its effects has broad prospects as a target for the treatment of lung, liver, kidneys, and other important organs injury in sepsis.


Assuntos
Sepse , Receptor 4 Toll-Like , Humanos , Receptor 4 Toll-Like/metabolismo , Transdução de Sinais , Fígado/metabolismo , Sepse/etiologia , Pulmão/metabolismo , Lipopolissacarídeos/farmacologia
3.
Biomed Pharmacother ; 173: 116346, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428312

RESUMO

BACKGROUND: This study aimed to investigate the effects of the combination of Epimedii Folium (EF) and Ligustri Lucidi Fructus (LLF) on regulating apoptosis and autophagy in senile osteoporosis (SOP) rats. METHODS: Firstly, we identified the components in the decoction and drug-containing serum of EL (EF&LLF) by Ultra performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF-MS). Secondly, SOP rats were treated with EF, LLF, EL and caltrate to evaluate the advantages of EL. Finally, H2O2-, chloroquine-, and MHY1485-induced osteoblasts were treated with different doses of EL to reveal the molecular mechanism of EL. We detected bone microstructure, oxidative stress levels, ALP activity and the expressions of Bax, Bcl-2, caspase3, P53, Beclin-1, p-PI3K, PI3K, p-Akt, Akt, p-mTOR, mTOR, and LC3 in vivo and in vitro. RESULTS: 36 compounds in EL decoction and 23 in EL-containing serum were identified, including flavonoids, iridoid terpenoids, phenylethanoid glycosides, polyols and triterpenoids. EL could inhibit apoptosis activity and increase ALP activity. In SOP rats and chloroquine-inhibited osteoblasts, EL could improve bone tissue microstructure and osteoblasts functions by upregulating Bcl-2, Beclin1, and LC3-II/LC3-I, while downregulating p53 in all treatment groups. In H2O2-induced osteoblasts, EL could upregulate the protein and mRNA expressions of Bcl-2 while downregulate LC3-II/LC3-I, p53 and Beclin1. Besides, EL was able to down-regulate PI3K/AKT/mTOR pathway which activated in SOP rats and MHY1485-induced osteoblasts. CONCLUSIONS: These findings demonstrate that EL with bone protective effects on SOP rats by regulating autophagy and apoptosis via PI3K/Akt/mTOR signaling pathway, which might be an alternative medicine for the treatment of SOP.


Assuntos
Medicamentos de Ervas Chinesas , Ligustrum , Osteoporose , Ratos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ligustrum/química , Ligustrum/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteína Beclina-1/metabolismo , Peróxido de Hidrogênio/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Osteoporose/tratamento farmacológico , Osteoblastos , Apoptose , Autofagia , Cloroquina/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
4.
Heliyon ; 10(4): e25990, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404795

RESUMO

The diverse applications of various tissues of Polygonum Multiflorum (PM) encompass the use of its leaf and bud as tea and vegetables, as well as the utilization of its expanded root tubers and caulis as medicinal substances. However, previous studies in the field of metabolomics have primarily focused on the medicinal properties of PM. In order to investigate the potential for broader applications of other tissues within PM, a metabolomic analysis was conducted for the first time using UPLC-Q-TOF-MS/MS on 15 fresh PM tissues. A total of 231 compounds, including newly discovered compounds such as torosachrysone and dihydro-trihydroxystilbene acid derivatives, were identified within PM. Through clustering analysis, the PM tissues were categorized into edible and medicinal parts, with edible tissues exhibiting higher levels of phenolic acids, organic acids, and flavonoids, while the accumulation of quinones, dianthrones, stilbenes, and xanthones was observed in medicinal tissues. Comparative analysis demonstrated the potential application of discarded tissues, such as unexpanded root tuber (an industrial alternative to expanded root tuber) and young caulis (with edible potential). Moreover, the quantification of representative metabolites indicated that flowers and buds contained significant amounts of flavonoids or phenolic acids, suggesting their potential as functional food. Additionally, the edible portion of PM exhibited a high content of quercitrin, ranging from 0.59 to 10.37 mg/g. These findings serve as a valuable point of reference for the expanded utilization of PM tissues, thereby mitigating resource waste in this plant.

5.
Anal Chem ; 96(6): 2637-2642, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38305901

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas12a nucleases have emerged as a promising alternative to CRISPR-Cas9 in gene editing and expression regulation. However, the adoption of Cas12a has been hindered due to general off-target activities and limited efficiency. Here, we utilized a hybrid engineered Cas12a variant and hairpin-spacer crRNAs (h-CAP) to enhance the specificity and efficiency of the CRISPR-Cas12a system. Leveraging the h-CAP strategy, we demonstrate both single-base-specific and multiplex gene expression regulation in human cells.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Humanos , Sistemas CRISPR-Cas/genética , Endonucleases/metabolismo
6.
Anal Chem ; 96(2): 668-675, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38176010

RESUMO

Lead is a widespread environmental hazard that can adversely affect multiple biological functions. Blood cells are the initial targets that face lead exposure. However, a systematic assessment of lead dynamics in blood cells at single-cell resolution is still absent. Herein, C57BL/6 mice were fed with lead-contaminated food. Peripheral blood was harvested at different days. Extracted red blood cells and leukocytes were stained with 19 metal-conjugated antibodies and analyzed by mass cytometry. We quantified the time-lapse lead levels in 12 major blood cell subpopulations and established the distribution of lead heterogeneity. Our results show that the lead levels in all major blood cell subtypes follow lognormal distributions but with distinctively individual skewness. The lognormal distribution suggests a multiplicative accumulation of lead with stochastic turnover of cells, which allows us to estimate the lead lifespan of different blood cell populations by calculating the distribution skewness. These findings suggest that lead accumulation by single blood cells follows a stochastic multiplicative process.


Assuntos
Chumbo , Longevidade , Animais , Camundongos , Chumbo/toxicidade , Camundongos Endogâmicos C57BL , Leucócitos , Eritrócitos
7.
Nat Plants ; 9(12): 1986-1999, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38012346

RESUMO

Tea is one of the world's oldest crops and is cultivated to produce beverages with various flavours. Despite advances in sequencing technologies, the genetic mechanisms underlying key agronomic traits of tea remain unclear. In this study, we present a high-quality pangenome of 22 elite cultivars, representing broad genetic diversity in the species. Our analysis reveals that a recent long terminal repeat burst contributed nearly 20% of gene copies, introducing functional genetic variants that affect phenotypes such as leaf colour. Our graphical pangenome improves the efficiency of genome-wide association studies and allows the identification of key genes controlling bud flush timing. We also identified strong correlations between allelic variants and flavour-related chemistries. These findings deepen our understanding of the genetic basis of tea quality and provide valuable genomic resources to facilitate its genomics-assisted breeding.


Assuntos
Camellia sinensis , Camellia sinensis/genética , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Genômica , Chá
8.
Indian J Ophthalmol ; 71(12): 3607-3614, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37991291

RESUMO

Nowadays, people give more importance and pay closer attention to the condition of their eyelids and lid margins. This increased recognition of eyelid hygiene is due to the growing awareness that improper eyelid cleaning might lead to various ocular surface diseases such as blepharitis and meibomian gland dysfunction. These ocular surface diseases can greatly affect people's quality of life. This article reviews the latest procedures for proper eyelid cleaning, including indications, methods, tools, detergents, and clinical applications, to maintain a healthy ocular surface and assist in the treatment of dry eye and blepharitis.


Assuntos
Blefarite , Síndromes do Olho Seco , Doenças Palpebrais , Disfunção da Glândula Tarsal , Humanos , Qualidade de Vida , Pálpebras , Blefarite/diagnóstico , Blefarite/terapia , Higiene , Síndromes do Olho Seco/terapia , Glândulas Tarsais , Doenças Palpebrais/diagnóstico , Lágrimas
9.
Angew Chem Int Ed Engl ; 62(44): e202309837, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37710395

RESUMO

The accurate, rapid, and sensitive identification of cancer cells in complex physiological environments is significant in biological studies, personalized medicine, and biomedical engineering. Inspired by the naturally confined enzymes on fluid cell membranes, a fluidly confined CRISPR-based DNA reporter (FINDER) was developed on living cell membranes, which was successfully applied for rapid and sensitive cancer cell identification in clinical blood samples. Benefiting from the spatial confinement effect for improved local concentration, and membrane fluidity for higher collision efficiency, the activity of CRISPR-Cas12a was, for the first time, found to be significantly enhanced on living cell membranes. This new phenomenon was then combined with multiple aptamer-based DNA logic gate for cell recognition, thus a FINDER system capable of accurate, rapid and sensitive cancer cell identification was constructed. The FINDER rapidly identified target cells in only 20 min, and achieved over 80 % recognition efficiency with only 0.1 % of target cells presented in clinical blood samples, indicating its potential application in biological studies, personalized medicine, and biomedical engineering.


Assuntos
Técnicas Biossensoriais , Neoplasias , Membrana Celular , DNA , Fluidez de Membrana , Oligonucleotídeos , Bioengenharia , Sistemas CRISPR-Cas/genética , Neoplasias/genética
10.
Cell Death Discov ; 9(1): 307, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37612272

RESUMO

Many different types of stem cells utilize asymmetric cell division (ACD) to produce two daughter cells with distinct fates. Haspin-catalyzed phosphorylation of histone H3 at Thr3 (H3T3ph) plays important roles during mitosis, including ACD in stem cells. However, whether and how Haspin functions in ACD regulation remains unclear. Here, we report that Haspin knockout (Haspin-KO) mouse embryonic stem cells (mESCs) had increased ratio of ACD, which cumulatively regulates cell fate decisions. Furthermore, Wnt5a is significantly downregulated due to decreased Pax2 in Haspin-KO mESCs. Wnt5a knockdown mESCs phenocopied Haspin-KO cells while overexpression of Wnt5a in Haspin-KO cells rescued disproportionated ACD. Collectively, Haspin is indispensable for mESCs to maintain a balanced ratio of ACD, which is essential for normal development and homeostasis.

11.
Front Immunol ; 14: 1152855, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37090704

RESUMO

Mucosal vaccines have great potential and advantages in preventing infection caused by multiple pathogens. In developing mucosal vaccines, the biggest challenge comes from finding safe and effective adjuvants and drug delivery systems. Great progress has been made in the generation of mucosal adjuvants using detoxified bacterial toxin derivatives, pathogen-related molecules, cytokines, and various vaccine delivery systems. However, many problems, relating to the safety and efficacy of mucosal vaccine adjuvants, remain. Certain natural substances can boost the immune response and thus could be used as adjuvants in vaccination. These natural-product-based immune adjuvants have certain advantages over conventional adjuvants, such as low toxicity, high stability, and low cost of production. In this review, we summarize the latest natural-product-based immune adjuvants, and discuss their properties and clinical applications.


Assuntos
Produtos Biológicos , Vacinas , Adjuvantes de Vacinas , Produtos Biológicos/farmacologia , Vacinação , Adjuvantes Imunológicos , Adjuvantes Farmacêuticos
12.
Kidney Int ; 104(1): 124-138, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36963487

RESUMO

Open-heart surgery is associated with high morbidity, with acute kidney injury (AKI) being one of the most commonly observed postoperative complications. Following open-heart surgery, in an observational study we found significantly higher numbers of blood neutrophils in a group of 13 patients with AKI compared to 25 patients without AKI (AKI: 12.9±5.4 ×109 cells/L; non-AKI: 10.1±2. 9 ×109 cells/L). Elevated serum levels of neutrophil extracellular trap (NETs) components, such as dsDNA, histone 3, and DNA binding protein Y-box protein (YB)-1, were found within the first 24 hours in patients who later developed AKI. We could demonstrate that NET formation and hypoxia triggered the release of YB-1, which was subsequently shown to act as a mediator of kidney tubular damage. Experimentally, in two models of AKI mimicking kidney hypoperfusion during cardiac surgery (bilateral ischemia/reperfusion (I/R) and systemic lipopolysaccharide (LPS) administration), a neutralizing YB-1 antibody was administered to mice. In both models, prophylactic YB-1 antibody administration significantly reduced the tubular damage (damage score range 1-4, the LPS model: non-specific IgG control, 0.92±0.23; anti-YB-1 0.65±0.18; and in the I/R model: non-specific IgG control 2.42±0.23; anti-YB-1 1.86±0.44). Even in a therapeutic, delayed treatment model, antagonism of YB-1 ameliorated AKI (damage score, non-specific IgG control 3.03±0.31; anti-YB-1 2.58±0.18). Thus, blocking extracellular YB-1 reduced the effects induced by hypoxia and NET formation in the kidney and significantly limited AKI, suggesting that YB-1 is part of the NET formation process and an integral mediator of cross-organ effects.


Assuntos
Injúria Renal Aguda , Armadilhas Extracelulares , Traumatismo por Reperfusão , Camundongos , Animais , Proteínas de Ligação a DNA , Lipopolissacarídeos , Rim , Isquemia/complicações , Hipóxia , Imunoglobulina G , Traumatismo por Reperfusão/complicações , Camundongos Endogâmicos C57BL
14.
Int J Ophthalmol ; 16(2): 201-207, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816200

RESUMO

AIM: To evaluate the correlation between Demodex infestation and keratitis, and to assess demodicosis using a simple approach. METHODS: A modified slit lamp illumination (at 40× magnification) was used to observe Demodex tails in 40 patients with refractory keratitis and 80 healthy controls. Bacterial smear and culture of the conjunctival sac and corneal lesion were performed to identify the pathogen. Tea tree oil ointment (TTOO) was added as a Demodex killing agent for lid scrubs to the treatment when Demodex infestation was confirmed. RESULTS: Demodex tails were found in all patients compared to 42/80 of the controls (P<0.01). Seventeen patients presented blepharitis, while 23 were free of scales and inflammation at the lid margin. The demodicosis was mild, moderate, and severe in 8, 19, and 13 patients, respectively, compared to mild in 42 controls (P<0.01). The keratitis was mild, moderate, and severe in 13, 19, and 8 patients, respectively. The severity of Demodex infestation was not correlated to the severity of keratitis (P=0.126). The growth of Staphylococcus was revealed in nine patients who did not react to antibiotic eye drops prior to the TTOO treatment. Patients' signs and symptoms got resolved after the lid scrub with TTOO. CONCLUSION: Ocular Demodex needs to be checked and treated in refractory keratitis patients with or without blepharitis. A slit-lamp illumination under high magnification favors the judgment of the severity of Demodex infestation.

15.
J Inorg Biochem ; 240: 112116, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36592511

RESUMO

The ratio of ligand to Cu(II) ions has an essential effect on the geometrical configuration and anti-tumour activity of metal-based complexes. In this work, we synthesised two Cu(II) thiosemicarbazone complexes, namely, [Cu(L)(Cl)] (C1) and [Cu3(L)2(Cl)4] (C2), by controlling the ratio of Cu(II) ion to ligand, to evaluate their anti-tumour activity. The ability of C1 to catalyze hydrogen peroxide to produce reactive oxygen species (ROS) was significantly higher than that of Cu(II) ion. Moreover, the bridge of Cu(II) and two molecules generated a new complex (C2), which, in contrast to C1, enhanced the generation of Fenton-like-triggered ROS. Consequently, the produced ROS depleted reduced glutathione, caused oxidative cell stress and promoted apoptosis through mitochondrial apoptotic pathways. In addition, C2 exhibited better tumour suppression than C1 in a nude mouse tumour xenograft model.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias , Tiossemicarbazonas , Animais , Camundongos , Humanos , Tiossemicarbazonas/química , Espécies Reativas de Oxigênio/metabolismo , Cobre/química , Ligantes , Complexos de Coordenação/química , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Íons , Antineoplásicos/química
17.
Immunology ; 168(1): 170-183, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36038992

RESUMO

Emerging studies have reported the expansion of myeloid-derived suppressor cells (MDSCs) in some autoimmune disorders, such as systemic lupus erythematosus (SLE), but the detailed molecular mechanisms of the aberrant expansion in SLE are still unclear. In the present study, we confirmed that the increased MDSCs positively correlated with disease activity in SLE patients. The suppressive capacity of MDSCs from patients with high activity was lower than that of MDSCs from patients with low activity. Moreover, the potential precursors for MDSCs, common myeloid progenitors (CMPs) and granulocyte-monocyte progenitors (GMPs), were markedly increased in the bone marrow (BM) aspirates of SLE patients. As an important regulator of cell fate decisions, aberrant activation of Notch signalling was reported to participate in the pathogenesis of SLE. We found that the expression of Notch1 and its downstream target gene hairy and enhancer of split 1 (Hes-1) increased markedly in GMPs from SLE patients. Moreover, the Notch1 signalling inhibitor DAPT profoundly relieved disease progression and decreased the proportion of MDSCs in pristane-induced lupus mice. The frequency of GMPs was also decreased significantly in lupus mice after DAPT treatment. Furthermore, the inhibition of Notch1 signalling could limit the differentiation of MDSCs in vitro. The therapeutic effect of DAPT was also verified in Toll-like receptor 7 (TLR7) agonist-induced lupus mice. Taken together, our results demonstrated that Notch1 signalling played a crucial role in MDSC differentiation in SLE. These findings will provide a promising therapy for the treatment of SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Células Supressoras Mieloides , Animais , Camundongos , Inibidores da Agregação Plaquetária/metabolismo , Inibidores da Agregação Plaquetária/farmacologia , Diferenciação Celular
19.
Waste Manag ; 155: 281-291, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36403412

RESUMO

Carbothermal reduction of cathode materials is an effective method to selectively extract lithium carbonate, both mechanical activation and microwave heating can enhance thermal reduction of mixed electrode materials. However, the mechanism of enhanced lithium extraction has not been fully revealed. This study attempts to uncover the synergistic strengthening mechanisms of mechanical activation-microwave reduction from the aspects of material structure, dielectric properties, reduction kinetics and lithium recovery rate. Mechanical activation induces amorphization and structural defects. The enhanced dielectric properties of materials and the induced hotspots/arc plasmas are also responsible for the enhancement of the reduction reaction. The average dissociation activation energy in the activated sample is 18.0 kJ·mol-1, which is 20.3 kJ·mol-1 lower than that of unactivated sample. The model-free method reveals that the carbothermic reduction process can be divided into three stages: (I) initial stage (α < 0.4(0.6)): the activation energy gradually decreases with the formation of strong microwave acceptor-reduction products; (II) transitional stage (0.4(0.6) < α < 0.7): the increase in mass transfer resistance leads to gradual increase in activation energy. Mechanical activation shortens the transitional reaction stage; (III) later reaction stage (α > 0.7), the decrease in activation energy may be attributed to the enhanced microwave absorption and CO reduction. The model-fitting method reveals that after mechanical activation, the reaction kinetic changes from reaction-order model to Ginstling-Brounshtein diffusion model. The optimized lithium extraction process parameters were: activation 300 rpm for 1.5 h, reduction temperature 550 °C. The research results can provide theoretical support for the enhanced extraction of cathode materials.

20.
Cell Transplant ; 31: 9636897221133818, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36398793

RESUMO

Dry eye is one of the most common chronic diseases in ophthalmology. It affects quality of life and has become a public health problem that cannot be ignored. The current treatment methods mainly include artificial tear replacement therapy, anti-inflammatory therapy, and local immunosuppressive therapy. These treatments are mainly limited to improvement of ocular surface discomfort and other symptoms. In recent years, regenerative medicine has developed rapidly, and ophthalmologists are working on new methods to treat dry eye. Mesenchymal stromal cells (MSCs) have anti-inflammatory, tissue repair, and immune regulatory effects, and have become a promising tool for the treatment of dry eye. These effects can also be produced by MSC-derived exosomes (MSC-Exos). As a cell-free therapy, MSC-Exos are hypoimmunogenic, serve more stable entities, and compared with MSCs, reduce the safety risks associated with the injection of live cells. This article reviews current knowledge about MSCs and MSC-Exos, and highlights the latest progress and future prospects of MSC-based therapy in dry eye treatment.


Assuntos
Síndromes do Olho Seco , Exossomos , Células-Tronco Mesenquimais , Humanos , Qualidade de Vida , Síndromes do Olho Seco/terapia , Anti-Inflamatórios
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