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2.
Iran J Pharm Res ; 22(1): e136238, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38116549

RESUMEN

In recent years, metal-organic frameworks (MOFs) have gained attention in the biomedical field, particularly as drug carriers for treating tumors. Therefore, we decided to synthesize a novel benzoic acid Zn-based MOF and study the Zn-based MOFs' drug-delivery properties and the drug-delivery system's anticancer effects. This study successfully synthesized a zinc-based MOF using solvent thermal synthesis. The crystal structure of a Zn-based MOF was investigated using thermogravimetric analysis, X-ray diffraction, and Fourier transform infrared spectroscopy. Subsequently, the results of UV spectrophotometry showed that Doxorubicin was successfully loaded with a loading amount of 33.74%. Furthermore, the drug release experiments demonstrated that the Zn-based MOF was pH-sensitive, releasing more at a pH of 3.8 than at pH 5.8 or 7.4. Finally, the Zn-based MOF loaded with drugs exhibited high antitumor activity against HepG2 cells while demonstrating remarkably low toxicity to normal cells (LO2). Taken together, these results demonstrate that the Zn-based MOF has the potential to serve as a carrier in the field of drug delivery systems.

3.
Front Chem ; 11: 1280999, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37927560

RESUMEN

Introduction: The rising incidence of type 2 diabetes has seriously affected international public health. The search for more drugs that can effectively treat diabetes has become a cutting-edge trend in research. Coenzyme Q10 (CoQ10) has attracted much attention in the last decade due to its wide range of biological activities. Many researchers have explored the clinical effects of CoQ10 in patients with type 2 diabetes. However, CoQ10 has low bio-availability due to its high lipophilicity. Therefore, we have structurally optimized CoQ10 in an attempt to exploit the potential of its pharmacological activity. Methods: A novel coenzyme Q10 derivative (L-50) was designed and synthesized by introducing a group containing bromine atom and hydroxyl at the terminal of coenzyme Q10 (CoQ10), and the antidiabetic effect of L-50 was investigated by cellular assays and animal experiments. Results: Cytotoxicity results showed that L-50 was comparatively low toxicity to HepG2 cells. Hypoglycemic assays indicated that L-50 could increase glucose uptake in IR-HepG2 cells, with significantly enhanced hypoglycemic capacity compared to the CoQ10. In addition, L-50 improved cellular utilization of glucose through reduction of reactive oxygen species (ROS) accumulated in insulin-resistant HepG2 cells (IR-HepG2) and regulation of JNK/AKT/GSK3ß signaling pathway, resulting in hypoglycemic effects. Furthermore, the animal experiments demonstrated that L-50 could restore the body weight of HFD/STZ mice. Notably, the findings suggested that L-50 could improve glycemic and lipid metabolism in HFD/STZ mice. Moreover, L-50 could increase fasting insulin levels (FINS) in HFD/STZ mice, leading to a decrease in fasting blood glucose (FBG) and hepatic glycogen. Furthermore, L-50 could recover triglycerides (TG), total cholesterol (T-CHO), lipoprotein (LDL-C) and high-density lipoprotein (HDL-C) levels in HFD/STZ mice. Discussion: The addition of a bromine atom and a hydroxyl group to CoQ10 could enhance its anti-diabetic activity. It is anticipated that L-50 could be a promising new agent for T2DM.

4.
Asia Pac J Oncol Nurs ; 10(6): 100238, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37273821

RESUMEN

This report presents a case involving a 21-year-old male patient with acute promyelocytic leukemia, where the peripherally inserted central catheter (PICC) tip location was diagnosed differently using ultrasound and computed tomography. The PICC was inserted into the left upper arm via the basilic vein. Echocardiography performed in the left lateral recumbent position suggested the PICC tip to be in the right atrium, deepest at the level of the tricuspid annulus. However, trans-catheter contrast-enhanced echocardiography, performed with a different posture involving left shoulder abduction and slight external rotation, revealed the tip to be at the cavo-atrial junction. Additionally, chest computed tomography, conducted in the supine position with raised arms, indicated the tip to be located at the upper one-third of the superior vena cava. These contradictory diagnoses can be attributed to the use of different body postures during the assessments. Considering the clinical efficacy and safety, it is crucial to fully consider the influence of multiple postures on PICC tip location during placement and determination. We recommend incorporating at least two opposite extreme daily postures to assess the nearest and farthest positions of the tip, ensuring effective and safe PICC placement and reducing the risk of complications.

5.
IEEE Trans Nanobioscience ; 21(4): 549-559, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34851831

RESUMEN

Lycorine-nanoparticles (LYC-NPs) were successfully synthesized using anti-solvent precipitation-freeze drying method, and characterized using transmission electron microscopy (TEM), particle size analysis and Fourier transform infrared spectroscopy (FTIR). Then, the antitumor effects of LYC-NPs against HepG2 cells were investigated, and the underlying molecular mechanisms were explored. Our results showed that LYC-NPs displayed potent antiproliferative against HepG2 cells concentration dependently. Flow cytometry analysis exhibited that LYC-NPs triggered apoptosis and impeded cell cycle in G0/G1 phase. Moreover, the up-regulated expression of cleaved caspases-3 and Bax, and decrease of mitochondrial membrane potential and the Bcl-2 expression were involved in LYC-NPs apoptosis, implying that LYC-NPs induced apoptosis via the mitochondrial-mediated apoptosis pathway. Furthermore, LYC-NPs distinctly impaired HepG2 cells migration and invasion with down-regulation of matrix metalloproteinase-2 (MMP-2) and MMP-9 expression. These results indicated that LYC-NPs could be an favorable agent for restraining the growth and metastasis of HepG2 cells.


Asunto(s)
Metaloproteinasa 2 de la Matriz , Nanopartículas , Alcaloides de Amaryllidaceae , Apoptosis , Células Hep G2 , Humanos , Metaloproteinasa 2 de la Matriz/farmacología , Metaloproteinasa 9 de la Matriz/farmacología , Nanopartículas/química , Fenantridinas , Proteína X Asociada a bcl-2/metabolismo , Proteína X Asociada a bcl-2/farmacología
6.
Front Chem ; 9: 762255, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34900934

RESUMEN

The lysozyme-modified nanoparticles (LY@ZnO NPs) were synthesized by the reduction-oxidation method, and the morphology and structure of LY@ZnO were analyzed by Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (XRD), scanning electron microsclope (SEM), and particle size analysis. The antibacterial effects of LY@ZnO against Escherichia coli (E. coli, Gram-negative bacteria) and Staphylococcus aureus (S. aureus, Gram-positive bacteria) were discussed by measuring the zone of inhibition (ZOI) and growth inhibition. The antimicrobial experiments showed that the LY@ZnO NPs possessed better antibacterial activity than ZnO. Besides, the antibacterial mechanism of LY@ZnO was also investigated, which was attributed to the generation of reactive oxygen species (ROS). Furthermore, the toxicities of LY@ZnO in vivo and in vitro were discussed by the cell counting kit-8 method and animal experiments, showing that LY@ZnO possessed excellent biocompatibility. Finally, the therapeutic effect of LY@ZnO on a rat skin infection model caused by methicillin-resistant Staphylococcus aureus (MRSA) was also studied, which exhibited good anti-infective activity. Our findings showed that LY@ZnO possessed remarkable antibacterial ability due to its excellent membrane permeability and small particle size. Besides, LY@ZnO also exhibited certain stability and great safety, which showed tremendous prospects for microbial infection in patients. It would also be helpful for a better understanding of the enzyme-modified nanomaterials against bacteria.

7.
Artículo en Inglés | MEDLINE | ID: mdl-32881685

RESUMEN

Early diagnosis is critical for the prevention and control of the coronavirus disease 2019 (COVID-19). We attempted to apply a protocol using teleultrasound, which is supported by the 5G network, to explore the feasibility of solving the problem of early imaging assessment of COVID-19. Four male patients with confirmed or suspected COVID-19 were hospitalized in isolation wards in two different cities. Ultrasound specialists, located in two other different cities, carried out the robot-assisted teleultrasound and remote consultation in order to settle the problem of early cardiopulmonary evaluation. Lung ultrasound, brief echocardiography, and blood volume assessment were performed. Whenever difficulties of remote manipulation and diagnosis occurred, the alternative examination was repeated by a specialist from another city, and in sequence, remote consultation was conducted immediately to meet the consensus. The ultrasound specialists successfully completed the telerobotic ultrasound. Lung ultrasound indicated signs of pneumonia with varying degrees in all cases and mild pleural effusion in one case. No abnormalities of cardiac structure and function and blood volume were detected. Remote consultation on the issue of manipulation practice, and the diagnosis in one case was conducted. The cardiopulmonary information was delivered to the frontline clinicians immediately for further treatment. The practice of teleultrasound protocol makes early diagnosis and repeated assessment available in the isolation ward. Ultrasound specialists can be protected from infection, and personal protective equipment can be spared. Quality control can be ensured by remote consultations among doctors. This protocol is worth consideration as a feasible strategy for early imaging assessment in the COVID-19 pandemic.


Asunto(s)
Infecciones por Coronavirus/diagnóstico por imagen , Neumonía Viral/diagnóstico por imagen , Robótica/métodos , Telemedicina/métodos , Ultrasonografía/métodos , Betacoronavirus , COVID-19 , Diagnóstico Precoz , Diseño de Equipo , Humanos , Masculino , Pandemias , Proyectos Piloto , SARS-CoV-2
8.
Front Immunol ; 11: 518, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32296431

RESUMEN

Little is known about how tuberculosis (TB) impairs dendritic cell (DC) function and anti-TB immune responses. We previously showed that the B and T lymphocyte attenuator (BTLA), an immune inhibitory receptor, is involved in TB pathogenesis. Here, we examined whether BTLA expression in TB affects phenotypic and functional aspects of DCs. Active TB patients exhibited higher expression of BTLA in myeloid dendritic cells (mDCs) and plasmacytoid DCs (pDCs) subsets compared with healthy controls (HCs). BTLA expression was similarly high in untreated TB, TB relapse, and sputum-bacillus positive TB, but anti-TB therapy reduced TB-driven increases in frequencies of BTLA+ DCs. BTLA+ DCs in active TB showed decreased expression of the DC maturation marker CD83, with an increased expression of CCR7 in mDCs. BTLA+ DCs in active TB displayed a decreased ability to express HLA-DR and to uptake foreign antigen, with a reduced expression of the co-stimulatory molecule CD80, but not CD86. Functionally, BTLA+ DCs in active TB showed a decreased production of IL-12 and IFN-α as well as a reduced ability to stimulate allogeneic T-cell proliferative responses. BTLA+ mDCs produced larger amounts of IL-4 and TGF-ß than BTLA- mDCs in both HCs and APT patients. BTLA+ DCs from active TB patients showed a reduced ability to stimulate Mtb antigen-driven Th17 and Th22 polarizations as compared to those from HCs. Conversely, these BTLA+ DCs more readily promoted the differentiation of T regulatory cells (Treg) and Th2 than those from HCs. These findings suggest that TB-driven BTLA expression in DCs impairs the expression of functional DC surrogate markers and suppress the ability of DCs to induce anti-TB Th17 and Th22 response while promoting Th2 and Foxp3+ Tregs.


Asunto(s)
Células Dendríticas/inmunología , Receptores Inmunológicos/inmunología , Linfocitos T Reguladores/inmunología , Células Th2/inmunología , Tuberculosis Pulmonar/inmunología , Adolescente , Adulto , Anciano , Diferenciación Celular/inmunología , Femenino , Humanos , Interferón-alfa/biosíntesis , Interleucina-12/biosíntesis , Interleucina-4/biosíntesis , Activación de Linfocitos/inmunología , Masculino , Persona de Mediana Edad , Factor de Crecimiento Transformador beta/biosíntesis , Adulto Joven
9.
J Inorg Biochem ; 194: 153-159, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30851664

RESUMEN

In this study, the zinc(II)-based coordination polymer, [Zn(CPDA)(NO3)2)](CPDA = 1,2-cyclopentanedicarboxylic acid) (1), had been successfully synthesized according to the hydrothermal method. Afterwards, 1 had been characterized by means of single crystal and power X-ray diffraction, elemental analysis, thermogravimetric analysis and infrared spectrum techniques. In addition, the antibacterial activities in vitro had been evaluated towards Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), respectively, through the growth inhibition and inhibition zone experimental methods. Our results indicated that 1 had displayed favorable antibacterial activity compared with the Zinc nitrate and the CPDA ligand. These findings had revealed that the antibacterial mechanism of 1 might be correlated with the production of reactive oxygen species (ROS) in cells.


Asunto(s)
Antibacterianos/farmacología , Complejos de Coordinación/farmacología , Acetilcisteína/farmacología , Antibacterianos/síntesis química , Complejos de Coordinación/síntesis química , Escherichia coli/efectos de los fármacos , Ligandos , Pruebas de Sensibilidad Microbiana , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Staphylococcus aureus/efectos de los fármacos , Zinc/química
10.
Parasitol Res ; 115(5): 1907-13, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26833322

RESUMEN

Malaria is a severe, life-threatening infectious disease that endangers human health. However, there are no vaccines or immune strategy of vaccines succeeding in both erythrocytic and pre-erythrocytic stage. During the liver stage of the Plasmodium life cycle, sporozoites invade the host liver cells. The sporozoites, then, induce a cellular immune response via the major histocompatibility complex (MHC) molecules on their surfaces. The cytotoxic T lymphocytes (CTLs) then recognize the corresponding antigen-MHC complex on the surfaces of these infected liver cells and kill them. However, dominant epitopes with high MHC affinity are prone to mutation due to immune selection pressure. CTLs evoked by the original dominant epitopes cannot recognize the mutated epitopes, leading to immune evasion. In this study, we have modified the cryptic epitopes of different antigens in the sporozoite and liver stages of Plasmodium falciparum to increase their immunogenicity without changing T cell antigen receptor (TCR)-peptide binding specificity. In addition, we have also added an important erythrocytic phase protective antigen, named apical membrane antigen 1 (AMA-1), to this process with the goal of constructing a complex multi-stage, multi-epitope recombinant DNA vaccine against P. falciparum. The vaccine was tested in HHD-2 mice. The method involved multiple stages of the P. falciparum life cycle as well as elucidation both humoral and cellular immunity. The conclusion drawn from the study was that the vaccine might provide an important theoretical and practical basis for generating effective preventative or therapeutic vaccine against P. falciparum.


Asunto(s)
Epítopos/genética , Vacunas contra la Malaria/inmunología , Malaria Falciparum/prevención & control , Plasmodium falciparum/genética , Secuencia de Aminoácidos , Animales , Eritrocitos , Inmunidad Celular , Ratones , Plasmodium falciparum/inmunología , Esporozoítos/inmunología , Vacunas Sintéticas/inmunología
11.
Luminescence ; 31(4): 965-71, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26577609

RESUMEN

Zinc oxide nanoparticles doped with bovine serum albumin were used to determine histidine in aqueous solutions using a fluorescence spectroscopic technique. The results showed that histidine effectively quenched the fluorescence of the modified ZnO nanoparticles, whereas other amino acids did not significantly affect the light emission, thereby allowing selective and sensitive histidine detection in amino acid mixtures. Under optimal conditions (pH 7.0, 25 °C, 10 min preincubation), the detection limit for histidine was ~ 9.87 × 10(-7) mol/L. The high value of the determined quenching rate constant Kq (3.30 × 10(13) L/mol/s) was consistent with a static quenching mechanism. Copyright © 2015 John Wiley & Sons, Ltd.


Asunto(s)
Histidina/análisis , Sustancias Luminiscentes/química , Nanopartículas/química , Albúmina Sérica Bovina/química , Óxido de Zinc/química , Animales , Bovinos , Espectrometría de Fluorescencia
12.
Luminescence ; 30(8): 1212-8, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25727213

RESUMEN

The interaction between ginsenoside Rh2 (G-Rh2) and calf thymus DNA (ctDNA) was investigated by spectroscopic methods including UV-vis absorption, fluorescence and circular dichroism (CD) spectroscopy, coupled with DNA melting techniques and viscosity measurements. Stern-Volmer plots at different temperatures proved that the quenching mechanism was a static quenching procedure. The thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS) were calculated to be -22.83 KJ · mol(-1) and 15.11 J · mol(-1) · K(-1) by van 't Hoff equation, suggesting that hydrophobic force might play a major role in the binding of G-Rh2 to ctDNA. Moreover, the fluorescence quenching study with potassium iodide as quencher indicated that the KSV (Stern-Volmer quenching constant) value for the bound G-Rh2 with ctDNA was lower than the free G-Rh2. The relative viscosity of ctDNA increased with the addition of G-Rh2 and also the ctDNA melting temperature increased in the presence of G-Rh2. Denatured DNA studies showed that quenching by single-stranded DNA was less than that by double-stranded DNA. The observed changes in CD spectra also demonstrated that the intensities of the positive and negative bands decreased with the addition of G-Rh2. The experimental results suggest that G-Rh2 molecules bind to ctDNA via an intercalative binding mode.


Asunto(s)
ADN/química , Ginsenósidos/química , Animales , Bovinos , Dicroismo Circular , Espectrometría de Fluorescencia , Termodinámica
13.
Luminescence ; 29(4): 307-13, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23788406

RESUMEN

Water-soluble ZnS quantum dots (QDs) modified by mercaptoacetic acid (MPA) were used to determinate quercetin in aqueous solutions by a fluorescence spectroscopic technique. The results showed that the fluorescence of the modified ZnS QDs could be quenched by quercetin effectively in physiological buffer solution. The optimum fluorescence intensity was found to be at incubation time 10 min, pH 7.0 and temperature 25°C. Under the optimal conditions, the detection limit of quercetin was 5.71 × 10(-7) mol/L. Moreover, the quenching mechanism was discussed to be a static quenching procedure, which was proved by the quenching rate constant Kq (1.14 × 10(13) L/mol/s).


Asunto(s)
Puntos Cuánticos/química , Quercetina/análisis , Espectrometría de Fluorescencia/métodos , Sulfuros/química , Compuestos de Zinc/química , Espectrometría de Fluorescencia/instrumentación
14.
Enzyme Microb Technol ; 51(1): 47-52, 2012 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-22579390

RESUMEN

Water soluble ZnS quantum dots (QDs) modified by mercaptoacetic acid (MAA) were used to determinate proton concentration in aqueous solutions by fluorescence spectroscopic technique. The results showed that the fluorescence of the water-soluble QDs could be quenched by proton concentration and the fluorescence intensity of the water-soluble QDs decreased linearly as the pH varied from 4.5 to 7.0. Based on this phenomenon, a convenient, rapid and specific method to determine of enzyme reaction kinetics was proposed. The modified ZnS QDs were successfully used as pH probes in monitoring the hydrolysis of glycidyl butyrate catalyzed by porcine pancreatic lipase (PPL). The proposed method was found to improve stability, sensitivity and a monitoring range for determination proton concentration as compared to the already described analytical methods based on p-Nitrophenoxide (PNP).


Asunto(s)
Lipasa/metabolismo , Puntos Cuánticos , Sulfuros , Compuestos de Zinc , Animales , Tampones (Química) , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , Microscopía Electrónica de Transmisión , Solubilidad , Espectrometría de Fluorescencia , Porcinos , Temperatura , Tioglicolatos , Agua , Difracción de Rayos X
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 84(1): 178-83, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-21968207

RESUMEN

The interaction between bovine serum albumin (BSA) and ZnS quantum dots (QDs) was studied by fluorescence, UV-vis spectroscopic techniques. The results showed that the fluorescence of BSA was strongly quenched by ZnS QDs and the quenching mechanism was discussed to be a static quenching procedure, which was proved by quenching rate constant K(q.) The recorded UV-vis data and the fluorescence data quenching by the QDs demonstrated that the interaction between them leads to the formation of QDs-BSA complex. Furthermore, the temperature effects on the structural and spectroscopic properties of individual QDs and protein and their bioconjugates (QDs-BSA) were also researched. It was found that, compared to the monotonically decrease of the individual QDs fluorescence intensity, the temperature dependence of the QDs-BSA emission had a much more complex behavior, highly sensitive to the conformational changes of the protein.


Asunto(s)
Puntos Cuánticos , Albúmina Sérica Bovina/metabolismo , Sulfuros/metabolismo , Compuestos de Zinc/metabolismo , Animales , Bovinos , Fluorescencia , Cinética , Microscopía Electrónica de Transmisión , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Temperatura , Difracción de Rayos X
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