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1.
Br J Haematol ; 204(4): 1307-1324, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38462771

RESUMEN

Multiple myeloma (MM) is the second most common malignant haematological disease with a poor prognosis. The limit therapeutic progress has been made in MM patients with cancer relapse, necessitating deeper research into the molecular mechanisms underlying its occurrence and development. A genome-wide CRISPR-Cas9 loss-of-function screening was utilized to identify potential therapeutic targets in our research. We revealed that COQ2 plays a crucial role in regulating MM cell proliferation and lipid peroxidation (LPO). Knockout of COQ2 inhibited cell proliferation, induced cell cycle arrest and reduced tumour growth in vivo. Mechanistically, COQ2 promoted the activation of the MEK/ERK cascade, which in turn stabilized and activated MYC protein. Moreover, we found that COQ2-deficient MM cells increased sensitivity to the LPO activator, RSL3. Using an inhibitor targeting COQ2 by 4-CBA enhanced the sensitivity to RSL3 in primary CD138+ myeloma cells and in a xenograft mouse model. Nevertheless, co-treatment of 4-CBA and RSL3 induced cell death in bortezomib-resistant MM cells. Together, our findings suggest that COQ2 promotes cell proliferation and tumour growth through the activation of the MEK/ERK/MYC axis and targeting COQ2 could enhance the sensitivity to ferroptosis in MM cells, which may be a promising therapeutic strategy for the treatment of MM patients.


Asunto(s)
Mieloma Múltiple , Animales , Humanos , Ratones , Línea Celular Tumoral , Proliferación Celular , Sistemas CRISPR-Cas , Modelos Animales de Enfermedad , Peroxidación de Lípido , Quinasas de Proteína Quinasa Activadas por Mitógenos/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico
2.
J Nanobiotechnology ; 22(1): 137, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38553725

RESUMEN

Immune checkpoint inhibitors (ICIs) combined with antiangiogenic therapy have shown encouraging clinical benefits for the treatment of unresectable or metastatic hepatocellular carcinoma (HCC). Nevertheless, therapeutic efficacy and wide clinical applicability remain a challenge due to "cold" tumors' immunological characteristics. Tumor immunosuppressive microenvironment (TIME) continuously natural force for immune escape by extracellular matrix (ECM) infiltration, tumor angiogenesis, and tumor cell proliferation. Herein, we proposed a novel concept by multi-overcoming immune escape to maximize the ICIs combined with antiangiogenic therapy efficacy against HCC. A self-delivery photothermal-boosted-NanoBike (BPSP) composed of black phosphorus (BP) tandem-augmented anti-PD-L1 mAb plus sorafenib (SF) is meticulously constructed as a triple combination therapy strategy. The simplicity of BPSP's composition, with no additional ingredients added, makes it easy to prepare and presents promising marketing opportunities. (1) NIR-II-activated BPSP performs photothermal therapy (PTT) and remodels ECM by depleting collagen I, promoting deep penetration of therapeutics and immune cells. (2) PTT promotes SF release and SF exerts anti-vascular effects and down-regulates PD-L1 via RAS/RAF/ERK pathway inhibition, enhancing the efficacy of anti-PD-L1 mAb in overcoming immune evasion. (3) Anti-PD-L1 mAb block PD1/PD-L1 recognition and PTT-induced ICD initiates effector T cells and increases response rates of PD-L1 mAb. Highly-encapsulated BPSP converted 'cold' tumors into 'hot' ones, improved CTL/Treg ratio, and cured orthotopic HCC tumors in mice. Thus, multi-overcoming immune escape offers new possibilities for advancing immunotherapies, and photothermal/chemical/immune synergistic therapy shows promise in the clinical development of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Ratones , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Antígeno B7-H1/metabolismo , Terapia Fototérmica , Sorafenib/farmacología , Línea Celular Tumoral , Microambiente Tumoral
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(2): 226-230, 2023 Mar.
Artículo en Zh | MEDLINE | ID: mdl-36949677

RESUMEN

The quality of sleep, a key physiological factor that regulates information, memory, decision making, and other vital brain functions, can affect important physiological functions of the human body. According to disease classification systems, sleep disorders can be categorized into more than 90 types, including sleep apnea, insomnia, and hypersomnia. It may cause a variety of adverse consequences, such as depression, anxiety and other emotional disorders, as well as physical diseases such as hypertension, diabetes and stroke. In addition, the relevant cardiovascular and cerebrovascular diseases and cognitive impairment not only harm physical health, but also are associated with workplace accidents and safety problems, constituting public safety hazards. Sleep disorders have become a major social and scientific problem that impacts on the national economy and the livelihood of the people. Research on sleep disorders should be given more attention by researchers and policy makers. Herein, we mainly discussed the latest findings and difficulties concerning research on the prevention and intervention of sleep disorders and proposed strategies and suggestions accordingly.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Trastornos del Sueño-Vigilia , Accidente Cerebrovascular , Humanos , Trastornos del Sueño-Vigilia/prevención & control , Trastornos del Sueño-Vigilia/complicaciones , Trastornos de Ansiedad/complicaciones , Trastornos del Inicio y del Mantenimiento del Sueño/prevención & control , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Ansiedad , Accidente Cerebrovascular/complicaciones
4.
Angew Chem Int Ed Engl ; 62(20): e202302429, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-36920791

RESUMEN

We report a unique vinyl coordination polymer (CP), [Zn(4-Fb)2 (tkpvb)]n (1, 4-HFb=4-fluorobenzoic acid, tkpvb=1,2,4,5-tetrakis(4-pyridylvinyl)benzene) that undergoes a rare photopolymerization reaction to form a two-dimensional CP integrated with a one-dimensional linear organic polymer. Upon light irradiation at different wavelengths, 1 exhibits an unprecedented phenomenon of photoinduced nonlinear lattice expansion. 1 can be uniformly dispersed in polyvinyl alcohol (PVA) to form the composite film of 1-PVA. When this film is exposed to UV light, internal minute stresses within crystallites are released by lattice expansion, resulting in a variety of photopolymerization-driven macroscopic mechanical motions. The findings provide new insights into the conversion of small lattice expansions of CPs into macroscopic mechanical motions based on photopolymerization reactions, which can promote the development of CPs-based smart photoactuators in the burgeoning field of microrobotics.

5.
Bioorg Chem ; 129: 106110, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36087551

RESUMEN

Using dehydroabietic acid as the lead compound for structural modification, 25 dehydroabietic acid derivatives were synthesized. Among them, compound D1 not only showed the strongest relaxation effect on the aortic vascular ring in vitro (Emax = 99.5 ± 2.1%, EC50 = 3.03 ± 0.96 µM), but also significantly reduced systolic and diastolic blood pressure in rats at a dose of 2.0 mg/kg in vivo. Next, the vascular protective effect of the best active D1 and its molecular mechanism were further investigated by HUVECs. The results showed that D1 induced endothelium-dependent diastole in the rat thoracic aorta in a concentration-dependent manner. Endothelium removal or aortic ring pretreatment with NG-nitro-l-arginine methylester (l-NAME), 1H-[1,2,4]-oxadiazolo-[4,3-a]-quinoxalin-1-one (ODQ), and tetraethylammonium (TEA) significantly inhibited D1-induced relaxation. In addition, wortmannin, KT5823, triciribine, diltiazem, BaCl2, 4-aminopyridine, indomethacin, propranolol, and atropine attenuated D1-induced vasorelaxation. D1 increased the phosphorylation of eNOS in HUVECs Furthermore, D1 attenuated the expression of TNF-α-induced cell adhesion molecules such as ICAM-1 and VCAM-1. However, this effect was attenuated by the eNOS inhibitors l-NAME and asymmetric dimethylarginine (ADMA). The findings suggest that D1-induced vasorelaxation through the PI3K/Akt/eNOS/NO/cGMP/PKG pathway by activating the KCa, Kir and KV channels or muscarinic and ß-adrenergic receptors, and inhibiting the l-type Ca2+ channels, which is closely related to the hypotensive action of the agent. Furthermore, D1 exhibits an inhibitory effect on vascular inflammation, which is associated with the observed vascular protective effects.


Asunto(s)
Vasodilatación , Vasodilatadores , Animales , Ratas , Aorta Torácica , NG-Nitroarginina Metil Éster/metabolismo , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Ratas Sprague-Dawley , Vasodilatadores/química , Tetraetilamonio/química
6.
Nature ; 530(7588): 98-102, 2016 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-26808898

RESUMEN

Methyl-CpG binding protein 2 (MeCP2) has crucial roles in transcriptional regulation and microRNA processing. Mutations in the MECP2 gene are found in 90% of patients with Rett syndrome, a severe developmental disorder with autistic phenotypes. Duplications of MECP2-containing genomic segments cause the MECP2 duplication syndrome, which shares core symptoms with autism spectrum disorders. Although Mecp2-null mice recapitulate most developmental and behavioural defects seen in patients with Rett syndrome, it has been difficult to identify autism-like behaviours in the mouse model of MeCP2 overexpression. Here we report that lentivirus-based transgenic cynomolgus monkeys (Macaca fascicularis) expressing human MeCP2 in the brain exhibit autism-like behaviours and show germline transmission of the transgene. Expression of the MECP2 transgene was confirmed by western blotting and immunostaining of brain tissues of transgenic monkeys. Genomic integration sites of the transgenes were characterized by a deep-sequencing-based method. As compared to wild-type monkeys, MECP2 transgenic monkeys exhibited a higher frequency of repetitive circular locomotion and increased stress responses, as measured by the threat-related anxiety and defensive test. The transgenic monkeys showed less interaction with wild-type monkeys within the same group, and also a reduced interaction time when paired with other transgenic monkeys in social interaction tests. The cognitive functions of the transgenic monkeys were largely normal in the Wisconsin general test apparatus, although some showed signs of stereotypic cognitive behaviours. Notably, we succeeded in generating five F1 offspring of MECP2 transgenic monkeys by intracytoplasmic sperm injection with sperm from one F0 transgenic monkey, showing germline transmission and Mendelian segregation of several MECP2 transgenes in the F1 progeny. Moreover, F1 transgenic monkeys also showed reduced social interactions when tested in pairs, as compared to wild-type monkeys of similar age. Together, these results indicate the feasibility and reliability of using genetically engineered non-human primates to study brain disorders.


Asunto(s)
Trastorno Autístico/genética , Trastorno Autístico/psicología , Modelos Animales de Enfermedad , Mutación de Línea Germinal/genética , Herencia/genética , Proteína 2 de Unión a Metil-CpG/genética , Proteína 2 de Unión a Metil-CpG/metabolismo , Animales , Animales Modificados Genéticamente , Ansiedad/genética , Ansiedad/psicología , Trastorno Autístico/metabolismo , Trastorno Autístico/fisiopatología , Encéfalo/metabolismo , Cognición/fisiología , Femenino , Humanos , Locomoción/genética , Locomoción/fisiología , Macaca fascicularis , Masculino , Fenotipo , Conducta Social , Inyecciones de Esperma Intracitoplasmáticas , Transgenes/genética
7.
Crit Rev Microbiol ; 46(6): 654-664, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32970952

RESUMEN

Huperzine A (HupA) is an effective inhibitor of acetylcholinesterase and has attracted great interest as a therapeutic candidate for Alzheimer's disease. However, the use of HupA is limited by resource scarcity as well as by its low yields from Huperzia serrata, its primary plant source. Recent studies have shown that this compound is produced by various endophytic fungi, thereby providing a promising alternative source, as fungi are much more amenable than plants owing to their simpler genetics and the ease of manipulation. In this review, we summarize the progress in research on the methods to increase HupA production, including fermentation conditions, fungal elicitors, gene expression, and the activation of key enzymes. This review provides guidance for further studies on HupA-producing endophytic fungi aimed at efficient HupA synthesis and accumulation, and offers new approaches for studies on the regulation of high-value bioactive secondary metabolites.


Asunto(s)
Alcaloides/biosíntesis , Endófitos/metabolismo , Hongos/metabolismo , Microbiología Industrial/tendencias , Endófitos/genética , Fermentación , Hongos/genética , Huperzia/metabolismo , Huperzia/microbiología , Sesquiterpenos
8.
Langmuir ; 36(5): 1165-1173, 2020 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-31961158

RESUMEN

Triboluminescence (TL) refers to the luminescence phenomenon at the material surface under the action of pressure or shear. This fascinating phenomenon can directly convert mechanical energy into light emission without the need for other auxiliary components; therefore, it attracts more and more researchers to conduct research in different wavelength ranges, such as X-ray, ultraviolet, visible light, and terahertz. However, there have been few reports on the study of the near-infrared (NIR) range, which is very important in the integrity of the triboluminescence research. In this research, we found that NIR light with a wavelength ranging from 800 to 1000 nm was generated by friction between solid metals and a quartz crystal. Analysis of the cross section of the quartz disk after friction revealed that the TL phenomenon had a strong relationship with the doping of metal grains into the silica. Density functional theory (DFT) and X-ray photoelectron spectroscopy were also conducted to further identify the results. We infer that such light emission arises from the implantation of metal grains into the surface of the quartz, which forms a metal-insulator junction with amorphous silica. Moreover, electron transition between the metal and the insulator, followed by a transition at the center of the defects, causes near-infrared light emission. Our research reveals the infrared luminescence behavior from a different perspective, the transfer of materials, and perhaps deepens the understanding of the near-infrared emission mechanism.

9.
Zhongguo Zhong Yao Za Zhi ; 45(13): 2993-3000, 2020 Jul.
Artículo en Zh | MEDLINE | ID: mdl-32726003

RESUMEN

To scientifically evaluate the intervention effect of Chinese medicine preventive administration(combined use of Huo-xiang Zhengqi Oral Liquid and Jinhao Jiere Granules) on community population in the case of coronavirus disease 2019(COVID-19), a large cohort, prospective, randomized, and parallel-controlled clinical study was conducted. Total 22 065 subjects were included and randomly divided into 2 groups. The non-intervention group was given health guidance only, while the traditional Chinese medicine(TCM) intervention group was given two coordinated TCM in addition to health guidance. The medical instructions were as follows. Huoxiang Zhengqi Oral Liquid: oral before meals, 10 mL/time, 2 times/day, a course of 5 days. Jinhao Jiere Granules: dissolve in boiling water and take after meals, 8 g/time, 2 times/day, a course of 5 days, followed up for 14 days, respectively. The study found that with the intake of medication, the incidence rate of TCM intervention group was basically maintained at a low and continuous stable level(0.01%-0.02%), while the non-intervention group showed an overall trend of continuous growth(0.02%-0.18%) from 3 to 14 days. No suspected or confirmed COVID-19 case occurred in either group. There were 2 cases of colds in the TCM intervention group and 26 cases in the non-intervention group. The incidence of colds in the TCM intervention group was significantly lower(P<0.05) than that in the non-intervention group. In the population of 16-60 years old, the incidence rate of non-intervention and intervention groups were 0.01% and 0.25%, respectively. The difference of colds incidence between the two groups was statistically significant(P<0.05). In the population older than 60 years old, they were 0.04% and 0.21%, respectively. The incidence of colds in the non-intervention group was higher than that in the intervention group, but not reaching statistical difference. The protection rate of TCM for the whole population was 91.8%, especially for the population of age 16-60(95.0%). It was suggested that TCM intervention(combined use of Huoxiang Zhengqi Oral Liquid and Jinhao Jiere Granules) could effectively protect community residents against respiratory diseases, such as colds, which was worthy of promotion in the community. In addition, in terms of safety, the incidence of adverse events and adverse reactions in the TCM intervention group was relatively low, which was basically consistent with the drug instructions.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus , Medicamentos Herbarios Chinos , Pandemias , Neumonía Viral , Adolescente , Adulto , COVID-19 , Infecciones por Coronavirus/tratamiento farmacológico , Humanos , Medicina Tradicional China , Persona de Mediana Edad , Neumonía Viral/tratamiento farmacológico , Estudios Prospectivos , SARS-CoV-2 , Adulto Joven , Tratamiento Farmacológico de COVID-19
10.
Chemistry ; 23(58): 14614-14622, 2017 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-28833778

RESUMEN

Enzyme immobilization is of increasing importance for biocatalysis, for which good supports are critical. Herein, two new Preyssler-type polyoxometalate (POM)-based coordination polymers, namely, {[Cu(H2 biim)2 ][{Cu(H2 biim)2 (µ-H2 O)}2 Cu(H2 biim)(H2 O)2 ]H[({Cu(H2 biim)(H2 O)2 }0.5 )2 ((µ-C3 HN2 Cl2 ){Cu(H2 biim)}2 ){Z(H2 O)P5 W30 O110 }]⋅x H2 O}n (1: Z=Na, x=9; 2: Z=Ag, x=10; H2 biim=2,2'-biimidazole) were designed and synthesized. Compounds 1 and 2 exhibit the same skeletons, which contain multiple CuII complex fragments and penta-supported {ZP5 W30 } (Z=Na, Ag) clusters. They were first employed to immobilize horseradish peroxidase (HRP). Results show that compounds 1 and 2 are good supports for HRP immobilization, and exhibit higher enzyme loading, lower loading times, and excellent reusability. The immobilized HRP (HRP/1 or HRP/2) was further applied to detect H2 O2 , and good sensitivity, wide linear range, low detection limit, and fast response were achieved. This work shows that POM-based hybrid materials are a new kind of promising support for enzyme immobilization.


Asunto(s)
Peroxidasa de Rábano Silvestre/química , Polímeros/química , Compuestos de Tungsteno/química , Complejos de Coordinación/química , Cobre/química , Cristalografía por Rayos X , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Peroxidasa de Rábano Silvestre/metabolismo , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/metabolismo , Microscopía Confocal , Conformación Molecular , Termogravimetría
11.
Appl Microbiol Biotechnol ; 101(19): 7201-7212, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28812125

RESUMEN

Ferredoxins are iron-sulfur protein that mediate electron transfer in cytochrome P450 mono-oxygenase (CYP)-related catalytic reactions in a wide variety of organisms. Rv1786 is a putative ferredoxin, encoded by a gene located downstream of the gene encoding CYP143A1 in the Mycobacterium tuberculosis genome. However, the structure and function of Rv1786 have remained unclear. Here, the recombinant Mtb Rv1786 was expressed, purified as a His-tagged form and characterized with [3Fe-4S] clusters as its cofactors using a series of measurements including SDS-PAGE, western blot, UV/Visible, MALDI-TOF/TOF-MS, and electron paramagnetic resonance spectroscopic analysis. Based on the assessments of surface plasmon resonance (SPR) and steady state kinetic assays, Rv1786 was found to be able to couple with both ferredoxin reductase A (FdrA) and flavoprotein reductase A (FprA) as redox partner, but with a stronger binding to FprA and a better coupling activity to FdrA. Preliminary structural and biochemical characterization of Mtb Rv1786 as a redox partner is presented here.


Asunto(s)
Proteínas Bacterianas/metabolismo , Ferredoxinas/metabolismo , Mycobacterium tuberculosis/metabolismo , Proteínas Recombinantes/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Catálisis , Clonación Molecular , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Ferredoxinas/genética , Proteínas Hierro-Azufre/genética , Proteínas Hierro-Azufre/metabolismo , Mycobacterium tuberculosis/genética , Filogenia , Proteínas Recombinantes/genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
12.
Zhongguo Zhong Yao Za Zhi ; 42(19): 3733-3738, 2017 Oct.
Artículo en Zh | MEDLINE | ID: mdl-29235288

RESUMEN

Squalene synthase of Alisma orientale catalyzes farnesyl diphosphate (FPP) to form squalene, which is the key regulatory enzyme of the carbon source flow to protostane triterpenes biosynthesis. For further research on the function and expression of AoSS gene, the open reading frame (ORF) of squalene synthase gene (accession no. JX866770) from A. orientale was subcloned into a prokaryotic expression vector pCzn1 and induced the expression of AoSS gene in Escherichia coli BL21(Roseta). The fusion protein was mainly in the form of inclusion bodies and purified to obtain high purity protein. By verifying its functionality through vitro enzymatic reaction, the results showed that the catalytic protein had the catalytic activity of FPP into squalene. In order to research the expression of AoSS in A. orientale, the purified protein was used to immunized rabbits to prepare polyclonal antibody which was then purified, the titer of the antibody was greater than 1∶51 200 by ELISA detection, and displayed good specificity by Western blotting. The prepared antibody was used for immunoassay of AoSS in different organs of A. orientale, and the results showed that the AoSS expression level was the highest in tubers, followed by leaves, and lowest in root. Successful construction of prokaryotic expression vector, validation of gene functions and establishment of rapid immunoassay lay the foundation for further researches on the function and regulation of AoSS gene, and also provide scientific basis on the application of the protostane triterpenes of A. orientale in the field of synthetic biology.


Asunto(s)
Alisma/enzimología , Farnesil Difosfato Farnesil Transferasa/metabolismo , Secuencia de Aminoácidos , Animales , Clonación Molecular , Farnesil Difosfato Farnesil Transferasa/genética , Hojas de la Planta/química , Raíces de Plantas/química , Tubérculos de la Planta/química , Conejos , Proteínas Recombinantes de Fusión/biosíntesis , Escualeno
13.
Chemistry ; 22(10): 3234-3238, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26699662

RESUMEN

In light of the serious challenge of severe global energy shortages, p-type dye-sensitized solar cells (p-DSSCs) have attracted increasing levels of interest. The potential of three Keggin-type transition metal-substituted polyoxometalates, TBA8 Na2 [SiW9 O37 {Co(H2 O)3 }]⋅ 11 H2 O (SiW9 Co3 ), TBA4 [(SiO4 )W10 MnIII2 O36 H6 ]⋅1.5 CH3 CN⋅ 2 H2 O (SiW10 MnIII2 ), and TBA3.5 H5.5 [(SiO4 )W10 MnIII/IV2 O36 ]⋅ 10 H2 O⋅0.5 CH3 CN (SiW10 MnIII/IV2 ) has been explored as pure inorganic dye photosensitizers for p-DSSCs (TBA=(n-C4 H9 )4 N+ ). The three dyes show overall conversion efficiencies of 0.038, 0.029, and 0.027 %, respectively, all of which are higher than that of coumarin 343 (0.017 %). These polyoxometalates are the first three pure inorganic dyes reported for use with p-DSSCs and therefore demonstrate a new strategy for designing efficient dyes, especially pure inorganic dyes. Moreover, they broaden the range of applications for polyoxometalates.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2027-30, 2016 Jul.
Artículo en Zh | MEDLINE | ID: mdl-30035867

RESUMEN

In this paper, we propose the surface plasmon resonance intensity modulation of the metal copper deposited on a titanium oxide thin film. Surface plasmon resonance (SPR) has a broad application prospect in various types of detectors and sensors. We first used the electron beam evaporation to obtain TiO2 thin films with the same thickness, and then we prepared copper film with the thickness ranging from 5 to 80 nm with magnetron sputtering method. The results show that the TiO2 film with different thickness copper thin films own different surface plasmon resonance modulation capability. The thinner copper film shows more obvious regulation. When the copper layer thickness is more than 20 nm, the resonance enhancement effect began to weaken because of better extinction capability.

15.
Materials (Basel) ; 17(7)2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38612193

RESUMEN

Controlling friction by light field is a low-cost, low-energy, non-polluting method. By applying ultraviolet light on the surface of photosensitive materials, the properties of the friction pairs or lubricant can be influenced, thus achieving the purpose of reducing friction. In this study, TiO2, an inorganic photosensitive material, was selected to investigate the modulating effect of light fields on friction lubrication when using polyalphaolefin (PAO) base oil as a lubricant, and the modulation law of light fields on the friction lubrication behavior was investigated under different loads (1-8 N), different speeds (20-380 mm/s), and different viscosities (10.1-108.6 mPa·s) of PAO base oil. The experimental results showed that light treatment could reduce the friction coefficient of PAO4 base oil lubrication from 0.034 to 0.016, with a reduction of 52.9% under conditions of 3 N-load and 56.5 mm/s-speed, and the best regulation effect could be achieved under the mixed lubrication condition. After TiO2 was treated with ultraviolet light, due to its photocatalytic property, PAO molecules were oxidized and adsorbed on the TiO2 surface to form an adsorption layer, which avoided the direct contact of rough peaks and thus reduced the friction coefficient. This study combines photosensitivity, photocatalysis, and friction, presenting a method to reduce the friction coefficient by applying a light field without changing the friction pairs or lubricants, which provides a new direction for friction modulation and gives new ideas for practical applications.

16.
Eur J Med Chem ; 267: 116223, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38342013

RESUMEN

Acute lung injury (ALI) is a clinically high mortality disease, which has not yet been effectively treated. The development of anti-ALI drugs is imminent. ALI can be effectively treated by inhibiting the inflammatory cascade and reducing the inflammatory response in the lung. Forsythia suspense is a common Chinese herbal medicine with significant anti-inflammatory activity. Using forsythin as the parent, 27 Forsythin derivatives were designed and synthesized, and the anti-AIL activity of these compounds was evaluated. Among them, compound B5 has the best activity to inhibit the release of IL-6, and the inhibition rate reaches 91.79% at 25 µM, which was 7.5 times that of the parent forsythin. In addition, most of the compounds have no significant cytotoxicity in vitro. Further studies showed that compound B5 had a concentration-dependent inhibitory effect on NO, IL-6 and TNF-α. And the IC50 values of compound B5 for NO and IL-6 are 10.88 µM and 4.93 µM, respectively. We also found that B5 could significantly inhibit the expression of some immune-related cytotoxic factors, including inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). In addition, B5 inhibits NF-κB/MAPK signaling pathway. In vivo experiments showed that B5 could alleviate lung inflammation in LPS-induced ALI mice and inhibit IL-6, TNF-α, COX-2 and iNOS. In summary, B5 has anti-inflammatory effects and alleviates ALI by regulating inflammatory mediators and inhibiting MAPK and NF-κB signaling pathways.


Asunto(s)
Lesión Pulmonar Aguda , Glucósidos , FN-kappa B , Ratones , Animales , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Ciclooxigenasa 2/metabolismo , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Antiinflamatorios/efectos adversos , Lipopolisacáridos/farmacología , Óxido Nítrico Sintasa de Tipo II/metabolismo
17.
Dalton Trans ; 53(24): 10226-10234, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38828535

RESUMEN

In aqueous solution, a novel triangle-like tungstovanadate estertin derivative K10H10.5[(W4O15(H2O)2){(SnCH2CH2COO)2(V0.75W10.75/V0.25O39)}{{(SnCH2CH2COO)2(µ-OH)}2(SnCH2CH2COO)(VW10O37)}2]·31H2O ((SnR)8-V3W35, R = CH2CH2COO) was assembled by a conventional synthetic method. (SnR)8-V3W35 is composed of one [VW11O39]7- ({VW11}) and two [VW10O37]9- ({VW10}) units connected by eight [Sn(CH2)2COO]2+ groups and a {W4O19} cluster. Interestingly, there exists a pentagonal bipyramid WO7 polyhedral center surrounded by two SnCO5 and three WO6 octahedra, forming a pentagonal {(WO7)W3(SnR)2} cluster in this polyoxometalate (POM), which is also the first example of a pentagonal structure formed by transition metals (TMs) and main group organometals in the POM family. Furthermore, the structure of this organic-inorganic hybrid POM also exhibits the largest number of organotin groups introduced into the POM system. It was characterized with various physico-chemical and spectroscopic methods, including X-ray single crystal and powder diffraction analysis, 119Sn and 51V NMR, IR, thermal gravimetric analysis (TGA), etc. In addition, the catalytic activity of (SnR)8-V3W35 as a mimic of peroxidase was evaluated using o-phenylenediamine (OPD) as a peroxidase substrate. The major factors influencing the oxidation reaction such as pH, the dosage of (SnR)8-V3W35, and concentrations of OPD and H2O2 were mainly studied. (SnR)8-V3W35 exhibits good peroxidase-like catalytic activity. From another perspective, the successful acquisition of (SnR)8-V3W35 further proves the instability and easy reassembly characteristics of TM-sandwich-type tungstovanadates, which also provides a new assembly strategy for synthesizing POM-estertin derivatives.

18.
Adv Sci (Weinh) ; : e2309569, 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38973195

RESUMEN

Radiotherapy plays a vital role in cancer therapy. However, the hypoxic microenvironment of tumors greatly limits the effectiveness, thus it is crucial to develop a simple, efficient, and safe radiosensitizer to reverse hypoxia and ameliorate the efficacy of radiotherapy. Inspired by the structure of canonical nanodrug Abraxane, herein, a native HSA-modified CaO2 nanoparticle system (CaO2-HSA) prepared by biomineralization-induced self-assembly is developed. CaO2-HSA will accumulate in tumor tissue and decompose to produce oxygen, altering the hypoxic condition inside the tumor. Simultaneously, ROS and calcium ions will lead to calcium overload and further trigger immunogenic cell death. Notably, its sensitizing enhancement ratio (SER = 3.47) is much higher than that of sodium glycididazole used in the clinic. Furthermore, in animal models of in situ oral cancer, CaO2-HSA can effectively inhibit tumor growth. With its high efficacy, facile preparation, and heavy-metal free biosafety, the CaO2-HSA-based radiosensitizer holds enormous potential for oral cancer therapy.

19.
Hum Gene Ther ; 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39078325

RESUMEN

ß654-thalassemia is caused by a point mutation in the second intron (IVS-II) of the ß-globin gene that activates a cryptic 3' splice site, leading to incorrect RNA splicing. Our previous study demonstrated that when direct deletion of the ß654 mutation sequence or the cryptic 3' splice site in the IVS-II occurs, correct splicing of ß-globin mRNA can be restored. Herein, we conducted an in-depth analysis to explore a more precise gene-editing method for treating ß654-thalassemia. A single base substitution of the cryptic 3' acceptor splice site was introduced in the genome of a ß654-thalassemia mouse model using CRISPR-Cas9-mediated homology-directed repair (HDR). All of the HDR-edited mice allow the detection of correctly spliced ß-globin mRNA. Pathological changes were improved compared with the non-edited ß654 mice. This resulted in a more than two-fold increase in the survival rate beyond the weaning age of the mice carrying the ß654 allele. The therapeutic effects of this gene-editing strategy showed that the typical ß-thalassemia phenotype can be improved in a dose-dependent manner when the frequency of HDR is over 20%. Our research provides a unique and effective method for correcting the splicing defect by gene-editing the reactive splicing acceptor site in a ß654 mouse model.

20.
Chin Med ; 19(1): 60, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589903

RESUMEN

BACKGROUND: Idiopathic pulmonary fibrosis is a persistent disease of the lung interstitium for which there is no efficacious pharmacological therapy. Protodioscin, a steroidal saponin, possesses diverse pharmacological properties; however, its function in pulmonary fibrosis is yet to be established. Hence, in this investigation, it was attempted to figure out the anti-pulmonary fibrosis influences of protodioscin and its pharmacological properties related to oxidative stress. METHODS: A mouse lung fibrosis model was generated using tracheal injections of bleomycin, followed by intraperitoneal injection of different concentrations of protodioscin, and the levels of oxidative stress and fibrosis were detected in the lungs. Multiple fibroblasts were treated with TGF-ß to induce their transition to myofibroblasts. It was attempted to quantify myofibroblast markers' expression levels and reactive oxygen species levels as well as Nrf2 activation after co-incubation of TGF-ß with fibroblasts and different concentrations of protodioscin. The influence of protodioscin on the expression and phosphorylation of p62, which is associated with Nrf2 activation, were detected, and p62 related genes were predicted by STRING database. The effects of Nrf2 inhibitor or silencing of the Nrf2, p62 and NBR1 genes, respectively, on the activation of Nrf2 by protodioscin were examined. The associations between p62, NBR1, and Keap1 in the activation of Nrf2 by protodioscin was demonstrated using a co-IP assay. Nrf2 inhibitor were used when protodioscin was treated in mice with pulmonary fibrosis and lung tissue fibrosis and oxidative stress levels were detected. RESULTS: In vivo, protodioscin decreased the levels of fibrosis markers and oxidative stress markers and activated Nrf2 in mice with pulmonary fibrosis, and these effects were inhibited by Nrf2 inhibitor. In vitro, protodioscin decreased the levels of myofibroblast markers and oxidative stress markers during myofibroblast transition and promoted Nrf2 downstream gene expression, with reversal of these effects after Nrf2, p62 and NBR1 genes were silenced or Nrf2 inhibitors were used, respectively. Protodioscin promoted the binding of NBR1 to p62 and Keap1, thereby reducing Keap1-Nrf2 binding. CONCLUSION: The NBR1-p62-Nrf2 axis is targeted by protodioscin to reduce oxidative stress and inhibit pulmonary fibrosis.

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