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1.
Artículo en Inglés | MEDLINE | ID: mdl-39317912

RESUMEN

Methotrexate (MTX), a frequently used chemotherapeutic agent, has limited water solubility, leading to rapid clearance even in local injections. In the present study, we developed folic acid-conjugated BSA-stabilized selenium-ZIF-8 core/shell nanoparticles for targeted delivery of MTX to combat breast cancer. FT-IR, XRD, SEM, TEM, and elemental mapping analysis confirmed the successful formation of FA-BSA@MTX@Se@ZIF-8. The developed nano-DDS had a mean diameter, polydispersity index, and zeta potential of 254.8 nm, 0.17, and - 16.5 mV, respectively. The release behavior of MTX from the nanocarriers was pH-dependent, where the cumulative release percentage at pH 5.4 was higher than at pH 7.4. BSA significantly improved the blood compatibility of nanoparticles so that after modifying their surface with BSA, the percentage of hemolysis decreased from 12.67 to 5.12%. The loading of methotrexate in BSA@Se@ZIF-8 nanoparticles reduced its IC50 on 4T1 cells from 40.29 µg/mL to 16.54 µg/mL, and by conjugating folic acid on the surface, this value even decreased to 12.27 µg/mL. In vivo evaluation of the inhibitory effect in tumor-bearing mice showed that FA-BSA@MTX@Se@ZIF-8 caused a 2.8-fold reduction in tumor volume compared to the free MTX, which is due to the anticancer effect of selenium nanoparticles, the pH sensitivity of ZIF-8, and the presence of folic acid on the surface as a targeting agent. More importantly, histological studies and animal body weight monitoring confirmed that developed nano-DDS does not have significant organ toxicity. Taking together, the incorporation of chemotherapeutics in folic acid-conjugated BSA-stabilized selenium-ZIF-8 nanoparticles may hold a significant impact in the field of future tumor management.

2.
Nanotechnology ; 35(47)2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39163872

RESUMEN

Quercetin (Qc) possesses anti-cancer properties, such as cell signaling, growth suppression, pro-apoptotic, anti-proliferative, and antioxidant effects. In this study, we developed an alginate-modified ZIF-8 (Alg@ZIF-8) to enhance the anti-tumor efficacy of Qc. The developed alginate-modified quercetin-loaded ZIF-8 (Alg@Qc@ZIF-8) was characterized using scanning electron microscope (SEM), dynamic light scattering (DLS), fourier transform infrared spectroscopy Thermogravimetric analysis, Brunauer-Emmett-Teller, and x-ray diffraction. The drug release pattern was evaluated at pH 5.4 and 7.4. The cytotoxicity of nanoparticles was assessed on the 4T1 cell line. Finally, the anti-tumor activity of Alg@Qc@ZIF-8 was evaluated in 4T1 tumor-bearing mice. SEM showed that the nanoparticles were spherical with a diameter of mainly below 50 nm. The DLS showed that the developed nanoparticles' hydrodynamic diameter, zeta potential, and polydispersity index were 154.9 ± 7.25 nm, -23.8 ± 5.33 mV, and 0.381 ± 0.09, respectively. The drug loading capacity was 10.40 ± 0.02%. Alg@Qc@ZIF-8 exhibited pH sensitivity, releasing more Qc at pH 5.4 (about 3.62 times) than at pH 7.4 after 24 h. Furthermore, the IC50value of Alg@Qc@ZIF-8 on the 4T1 cell line was 2.16 times lower than net Qc. Importantly, in tumor-bearing mice, Alg@Qc@ZIF-8 demonstrated enhanced inhibitory effects on tumor growth and lung metastasis compared to net Qc. Considering thein vitroandin vivooutcomes, Alg@Qc@ZIF-8 might hold great potential for effective breast cancer management.


Asunto(s)
Alginatos , Antineoplásicos , Estructuras Metalorgánicas , Nanocompuestos , Quercetina , Quercetina/farmacología , Quercetina/química , Animales , Nanocompuestos/química , Alginatos/química , Alginatos/farmacología , Ratones , Concentración de Iones de Hidrógeno , Línea Celular Tumoral , Antineoplásicos/farmacología , Antineoplásicos/química , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Femenino , Ratones Endogámicos BALB C , Liberación de Fármacos , Portadores de Fármacos/química , Supervivencia Celular/efectos de los fármacos , Humanos , Imidazoles
3.
Small ; : e2404506, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39051509

RESUMEN

Flexible all-solid-state asymmetric supercapacitors (FAASC) represent a highly promising power sources for wearable electronics. However, their energy density is relatively less as compared to the conventional batteries. Herein, a novel ultra-high energy density FAASC is developed using nickel-cobalt sulfide (NiCo2S4)/polyaniline (PANI)/manganese dioxide (MnO2) ternary composite on carbon fiber felt (CF) as positive and N, S-co-doped carbon nanofibers (CNF)/CF as negative electrode, respectively. Initially, porous δ-MnO2 nanoworm-like network is decorated on CF using potentiodynamic method. Subsequently, interconnected PANI nanostructures is grown on the MnO2 via a facile in situ chemical polymerization, followed by the electrodeposition of highly porous NiCo2S4 nanowalls. Benefiting from 3D porous structure of conductive CF and redox active properties of NiCo2S4, PANI and MnO2, FAASC achieved a superior energy storage capacity. Later, high-performance N, S-co-doped CNF/CF negative electrode is synthesized using electropolymerization of PANI nanofibers on CF, followed by the carbonization process. The assembled FAASC exhibits a wide voltage window of 2.2 V and remarkable specific capacitance of 143 F g-1 at a current density of 1 A g-1. The cell further delivers a superb energy density of 71.6 Wh kg-1 at a power density of 492.7 W kg-1, supreme cycle life and remarkable electrochemical stability under mechanical bending.

4.
J Biomater Sci Polym Ed ; 35(15): 2294-2314, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39037940

RESUMEN

In this study, a bovine serum albumin-decorated zeolitic imidazolate framework (ZIF-8@BSA) was used to enhance the anticancer and antimetastatic properties of methotrexate. SEM, DLS, FT-IR, and XRD confirmed the physicochemical suitability of the developed nanoparticles. According to the SEM analysis, the mean size of ZIF-8 nanoparticles was 68.5 ± 13.31 nm. The loading capacity and encapsulation efficiency of MTX@ZIF-8@BSA were 28.77 ± 2.54% and 96.3 ± 0.67%, respectively. According to the in vitro hemolysis test, MTX@ZIF-8@BSA showed excellent blood compatibility. MTX@ZIF-8@BSA exhibited pH sensitivity, releasing more MTX at pH 5.4 (1.73 times) than at pH 7.4. The IC50 value of MTX@ZIF-8@BSA on 4T1 cells was 32.7 ± 7.3 µg/mL after 48 h of treatment, outperforming compared to free MTX with an IC50 value of 53.3 ± 3.7 µg/mL. Treatment with MTX@ZIF-8@BSA resulted in superior tumor growth suppression in tumor-bearing mice than free MTX. Furthermore, based on histopathology tests, MTX@ZIF-8@BSA reduced the metastasis in lung and liver tissues. While there was not any noticeable toxicity in the vital organs of MTX@ZIF-8@BSA-receiving mice, free methotrexate resulted in severe toxicity in the kidneys and liver. According to the preliminary in vitro and in vivo findings, MTX@ZIF-8@BSA presents an attractive drug delivery system candidate for breast cancer due to its enhanced antitumor efficacy and lower toxicity.


Asunto(s)
Portadores de Fármacos , Metotrexato , Nanopartículas , Albúmina Sérica Bovina , Metotrexato/química , Metotrexato/farmacología , Metotrexato/administración & dosificación , Animales , Albúmina Sérica Bovina/química , Nanopartículas/química , Ratones , Línea Celular Tumoral , Portadores de Fármacos/química , Femenino , Ratones Endogámicos BALB C , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/administración & dosificación , Liberación de Fármacos , Zeolitas/química , Zeolitas/farmacología , Hemólisis/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Humanos , Bovinos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Imidazoles
5.
Iran J Basic Med Sci ; 27(7): 857-867, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38800017

RESUMEN

Objectives: Lipid-based drug delivery systems (DDS) can improve the pharmacokinetic (PK) parameters of some drugs. Especially those with a high volume of distribution (Vd) leading to off-target accumulation and toxicity. Amiodarone as an anti-arrhythmic agent induces hypothyroidism and liver disorders limiting its clinical indication. Materials and Methods: In the present study, amiodarone PK parameters and biodistribution after IV administration of four nano-formulations to rats were compared. The formulations were liposomes, solid lipid nanoparticles (SLN), PEGylated SLN (PEG-SLN), and nanoemulsions (NE). All formulations were optimized. Results: The nanoparticles were spherical with a diameter of 100-200 nm and sustained in vitro drug release in buffer pH 7.4. The best-fitted model for the plasma concentration-time profile was two-compartmental. In vivo studies indicated the most changes in PKs induced after liposome, SLN, and NE administration, respectively. The area under the curve (AUC) and maximum plasma concentration (Cmax) of liposomes, SLN, and NE were 22.5, 2.6, 2.46 times, and 916, 58, and 26 times higher than that of amiodarone solution, respectively (P-value<0.05). The heart-to-liver ratio of amiodarone was higher for nano-formulations compared to drug solution except for liposomes. Conclusion: Lipid-based particles can improve the PK parameters of amiodarone and its distribution in different tissues.

6.
J Drug Target ; 32(4): 444-455, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38445558

RESUMEN

In this study, a novel selenium@zeolitic imidazolate framework core/shell nanocomposite stabilised with alginate was used to improve the anti-tumour activity of curcumin. The developed alginate-stabilised curcumin-loaded selenium@zeolitic imidazolate framework (Alg@Cur@Se@ZIF-8) had a mean diameter of 159.6 nm and polydispersity index < 0.25. The release of curcumin from the nanocarrier at pH 5.4 was 2.69 folds as high as at pH 7.4. The bare nanoparticles showed haemolytic activity of about 12.16% at a concentration of 500 µg/mL while covering their surface with alginate reduced this value to 5.2%. By investigating cell viability, it was found that Alg@Cur@Se@ZIF-8 caused more cell death than pure curcumin. Additionally, in vivo studies showed that Alg@Cur@Se@ZIF-8 dramatically reduced tumour growth compared to free curcumin in 4T1 tumour-bearing mice. More importantly, the histological study confirmed that the developed drug delivery system successfully inhibited lung and liver metastasis while causing negligible toxicity in vital organs. Overall, due to the excellent inhibitory activity on cancerous cell lines and tumour-bearing animals, Alg@Cur@Se@ZIF-8 can be considered promising for breast cancer therapy.


Asunto(s)
Curcumina , Nanocompuestos , Nanopartículas , Neoplasias , Selenio , Ratones , Animales , Portadores de Fármacos , Alginatos , Neoplasias/tratamiento farmacológico , Concentración de Iones de Hidrógeno
7.
Exp Brain Res ; 242(6): 1291-1300, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38548893

RESUMEN

Neuro-architecture is a specific branch of architecture that studies how the physical environment can change our mental processes and influence our behaviors. One of the main purposes of this field is to use changes in brain activities as a measure to quantify attractiveness of the landscapes. In this study, we investigated how changes in elements of attractiveness influence ones' emotional perception and present the related pattern of changes in brain activities. Therefore, we implied five elements of attractiveness including mystery, visual openness, landscape or greenness, walkability, and social interaction using the Delphi method. Then, we made changes in each element separately to make the landscape more attractive and assessed their effects on a group of young adults. We used the self-assessment manikin questionnaire to measure the participants' emotional perception while the participants' brain activities were recorded using a 32-channel EEG while exposed to the landscape images. The results showed that changes in attractive elements of the landscape could significantly improve ones' emotional perception of the landscape. In addition, these changes are perceived by changing the oscillatory pattern of brain activities. We hope these findings could shed a light to use of neural markers in measurement of place attractiveness.


Asunto(s)
Electroencefalografía , Emociones , Humanos , Adulto Joven , Femenino , Masculino , Emociones/fisiología , Adulto , Encéfalo/fisiología , Ondas Encefálicas/fisiología , Belleza
8.
Rev Recent Clin Trials ; 18(4): 251-257, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37779398

RESUMEN

INTRODUCTION: Infertility and its treatment methods among couples have psychological and social consequences. To encounter these consequences, coping strategies are commonly used, which are influenced by various factors, such as the attitude of couples toward infertility. OBJECTIVE: This study aims to determine the relationship between attitudes toward infertility and stress-coping strategies among couples undergoing Assisted Reproduction Treatment, referring to the infertility clinic of Al-Zahra Educational Center. METHODS: This study was a cross-sectional study performed on 153 couples referred to Al-Zahra Infertility Clinic in Rasht. Three instruments (demographic questionnaire, attitude, and Lazarus coping strategies questionnaire) were used with regard to the inclusion restrictions. RESULTS: Between the two variables of individual and social information factors and the attitude of couples toward infertility, only the duration of infertility factor revealed a significant relationship (p <0.05); and in explaining the relationship between individual and social variables and coping strategies, the lack of insurance in both genders with an emotion-oriented strategy, the female infertility factor in women with the confrontational adjustment domain, and treatment in a discontinuous way in both genders have a significant relationship with the problem-oriented domain (p <0.05). Accountability and problem-solving strategies in women and an escapeavoidance strategy in infertile men have been identified as the most important predictors of attitude toward infertility. CONCLUSION: There is a relationship between attitudes toward infertility and coping strategies. However, the impact of community culture on the type of coping strategies used in this study has led to different results in some cases from other studies.


Asunto(s)
Habilidades de Afrontamiento , Infertilidad Femenina , Humanos , Femenino , Masculino , Adaptación Psicológica , Estrés Psicológico , Estudios Transversales , Reproducción
9.
J Pharm Sci ; 112(12): 3197-3208, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37777011

RESUMEN

In this study, a polymer-stabilized nanoemulsion (PNE) was developed to improve the inflammatory and analgesic activities of diclofenac (DA). DA-PNEs were prepared from sesame oil and poloxamer 188 (P188), polysorbate 80, and span 80 as emulsifiers and optimized by a systematic multi-objective optimization method. The developed DA-PNEs exhibited thermodynamical stability with low viscosity. The mean diameter, PDI, surface charge, and entrapment efficiency of DA-PNEs were 122.49±3.42 nm, 0.226±0.08, -47.3 ± 3.6 mV, and 93.57±3.4 %, respectively. The cumulative in vitro release profile of DA-PNEs was significantly higher than the neat drug in simulated gastrointestinal fluids. The anti-inflammatory activities of DA-PNEs were evaluated in the λ-carrageenan-induced paw edema model. To investigate the effect of P188 on analgesic and anti-inflammatory activities, a formulation without P188 was also prepared and named DA-NEs. Following oral administration, DA-PNEs showed a significantly higher (p<0.05) effect in reducing pain and inflammation symptoms as compared to free diclofenac and DA-NEs. Moreover, histopathological examination confirmed that DA-PNEs meaningfully reduced the extent of paw edema, comparable to that of DA. Taken together, the findings of the in vitro and in vivo studies suggest that diclofenac-loaded P188-stabilized nanoemulsion can be considered a potential drug delivery system for treating and controlling inflammatory disorders and alleviating pains.


Asunto(s)
Diclofenaco , Poloxámero , Humanos , Diclofenaco/farmacología , Emulsiones/farmacología , Antiinflamatorios/farmacología , Analgésicos/efectos adversos , Dolor/tratamiento farmacológico , Edema/inducido químicamente , Edema/tratamiento farmacológico , Convulsiones/tratamiento farmacológico
10.
Sci Rep ; 13(1): 13880, 2023 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-37620556

RESUMEN

In the study, a biomimetic platform for anti-inflammatory-based treatment of atherosclerotic plaque was developed. Gliclazide (GL) as an anti-inflammasome agent was encapsulated in PLGA nanoparticles (NP), which were coated by monocyte membrane using an extrusion procedure. The size and zeta potential of the nanoghost (NG) changed to 292 and - 10 nm from 189.5 to -34.1 in the core NP. In addition, the actual size of 62.5 nm with a coating layer of 5 nm was measured using TEM. The NG was also showed a sustained release profile with the drug loading content of about 4.7%. Beside to attenuated TNFα, decrease in gene expression levels of NLRP3, MyD88, NOS, IL-1ß, IL-18 and caspases 1/3/8/9 in LPS-primed monocytes exposed to NG strongly indicated remarkable inflammation control. After systemic toxicity evaluation and pharmacokinetic analysis of NP and NG, intravenous NG treatment of rabbits with experimentally induced atherosclerosis revealed remarkably less plaque lesions, foam cells, lipid-laden macrophages, and pathological issues in tunica media of aorta sections. Higher expression of CD163 than CD68 in aorta of NG-treated rabbits strongly reveals higher M2/M1 macrophage polarization. The bio/hemocompatible, biomimetic and anti-inflammatory NG can be considered as a potential platform for immunotherapy of particularly atherosclerosis in the field of personalized medicine.


Asunto(s)
Aterosclerosis , Gliclazida , Lagomorpha , Placa Aterosclerótica , Animales , Conejos , Biomimética , Aterosclerosis/tratamiento farmacológico , Placa Aterosclerótica/tratamiento farmacológico , Antiinflamatorios/farmacología
11.
J Biomed Mater Res B Appl Biomater ; 111(9): 1687-1696, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37246876

RESUMEN

Wide availability and easy accessibility of acetaminophen oral dosage forms increase the risk of intentional poisoning or unintentional organ toxicity, leading to a wide range of liver failure, nephrotoxicity, and neurotoxicity. In this study, an attempt was made to improve oral bioavailability and reduce the toxicity of acetaminophen using nanosuspension technology. The acetaminophen nanosuspensions (APAP-NSs) were prepared by a nano-precipitation method using polyvinyl alcohol and hydroxypropylmethylcellulose as stabilizers. The mean diameter of APAP-NSs was 124 ± 3.8 nm. The dissolution profile of APAP-NSs was significantly point-to-point higher than the coarse drug in simulated gastrointestinal fluids. The in vivo study revealed 1.6- and 2.8-fold increases in the AUC0-inf and Cmax of the drug, respectively, in APAP-NSs-receiving animals compared to the control group. Moreover, no deaths and no abnormalities in clinical signs, body weights, and necropsy findings were detected in the dose groups up to 100 mg/kg of the 28-day repeated oral dose toxicity study in mice.


Asunto(s)
Acetaminofén , Ratones , Animales , Acetaminofén/toxicidad , Administración Oral , Disponibilidad Biológica
12.
Eur J Transl Myol ; 32(4)2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35796740

RESUMEN

This descriptive study was performed on individuals who were referred to Imam Reza Hospital for fine needle aspiration biopsy (FNAB) based on the results of gray scale ultrasound and the decision of the referring physician. In addition to determining the gray scale characteristics of the nodules, shear wave elastography (SWE) was also performed and the results were recorded. These were also taken from the patients FNAB results. Finally, the findings of SWE and FNAB methods were compared and analyzed using SPSS software version 16. Based on the results presented herein, a significant relationship was observed between the results of SWE and FNA in the diagnosis of malignancy in solid thyroid nodules. This agreement was found to be higher in men (K = 0.866) than women (K = 0.849). Taken together, our data suggest that shear wave elastography can replace FNA in the diagnosis of malignancy in solid thyroid nodules.

13.
Brain Res ; 1781: 147786, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-35041841

RESUMEN

Targeted delivery of neurological therapeutic to the brain has been attracting more and more attention to the treatment of central nervous system (CNS) diseases. Nonetheless, the main obstacle in this road map is the existence of a blood-brain barrier (BBB) which limits the penetration efficiency of most CNS drugs into the brain parenchyma. This present investigation describes a facile synthetic strategy to prepare a highly biocompatible calcium-doped mesoporous silica nanoparticles (MSNs) functionalized by polysorbate-80 (PS) as targeting ligand to deliver rivastigmine (RV) into the brain via crossing the BBB. The developed nanosystem was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), Zeta potential, and N2-adsorption-desorption analysis. In vitro hemolysis studies were carried out to confirm the biocompatibility of the nanocarriers. Our in vivo studies in an animal model of rats showed that the RV-loaded nanosystem was able to enhance the brain-to-plasma concentration ratio, brain uptake clearance, and plasma elimination half-life of the drug compared to the free one drug following intravenous (IV) administration. The results revealed that functionalization of MSNs by PS is crucial to deliver RV into the brain, suggesting PS-functionalized MSNs could be an effective carrier to deliver RV to the brain while overcoming BBB.


Asunto(s)
Nanopartículas , Dióxido de Silicio , Animales , Encéfalo , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Polisorbatos , Porosidad , Ratas , Rivastigmina , Dióxido de Silicio/química , Espectroscopía Infrarroja por Transformada de Fourier
14.
Front Cell Dev Biol ; 10: 1050856, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36733338

RESUMEN

Induced pluripotent stem cells (iPSCs) exhibit an unlimited ability to self-renew and produce various differentiated cell types, thereby creating high hopes for both scientists and patients as a great tool for basic research as well as for regenerative medicine purposes. The availability and safety of iPSCs for therapeutic purposes require safe and highly efficient methods for production of these cells. Different methods have been used to produce iPSCs, each of which has advantages and disadvantages. Studying these methods would be very helpful in developing an easy, safe, and efficient method for the generation of iPSCs. Since iPSCs can be generated from somatic cells, they can be considered as valuable cellular resources available for important research needs and various therapeutic purposes. Coronavirus disease 2019 (COVID-19) is a disease that has endangered numerous human lives worldwide and currently has no definitive cure. Therefore, researchers have been rigorously studying and examining all aspects of COVID-19 and potential treatment modalities and various drugs in order to enable the treatment, control, and prevention of COVID-19. iPSCs have become one of the most attractive and promising tools in this field by providing the ability to study COVID-19 and the effectiveness of drugs on this disease outside the human body. In this study, we discuss the different methods of generation of iPSCs as well as their respective advantages and disadvantages. We also present recent applications of iPSCs in the study and treatment of COVID-19.

15.
Colloids Surf B Biointerfaces ; 209(Pt 2): 112151, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34687974

RESUMEN

In this research, lipase Km12 was immobilized on the glutaraldehyde-activated graphene oxide/chitosan/cellulose acetate nanofibers (GO/Chit/CA NFs) prepared by the electrospinning method. This immobilized lipase exhibited a higher activity value than the free lipase in the acidic pH region. This enzyme showed a 10 °C shift in the maximum temperature activity. Results displayed that the Vmax value of NFs-lipase was 0.64 µmol/min, while it was gained 0.405 µmol/min for the free lipase. The activity of NFs-lipase was reserved 100% after 10 min maintaining at 60 °C, in which the free lipase only kept 75% of its original activity. Moreover, a 20% enhancement in the lipase activity was observed for NFs-lipase after 180 min of incubation at 60 °C, compared to the free enzyme. Reusability studies exhibited that the immobilized lipase well-kept 80% of its original activity after 10 cycles of reusing. Results displayed that 14% of the protein was leaked from NFs-lipase at the same condition. Transesterification results indicated that the free lipase exhibited 65% and 85% conversation level of benzyl acetate after 12 and 24 h of incubation. Besides, the immobilized lipase showed 80% and 95% conversation level at the same condition. These results indicated the high performance of free and immobilized lipase in the production of benzyl acetate for applications in the perfume and cosmetic industries.


Asunto(s)
Quitosano , Nanofibras , Compuestos de Bencilo , Celulosa/análogos & derivados , Estabilidad de Enzimas , Enzimas Inmovilizadas/metabolismo , Glutaral , Grafito , Concentración de Iones de Hidrógeno , Lipasa/metabolismo , Temperatura
16.
Int J Biol Macromol ; 192: 1292-1303, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34687760

RESUMEN

In this study, due to the favorable properties of MOF compounds and fibrous materials, new nanostructures of Zr-MOF/PVP nanofibrous composites were synthesized by electrospinning procedure. The related features of these samples were characterized by relevant analyzes, including SEM, BET surface area analysis, XRD, and FTIR spectroscopy. The final product showed significant properties such as small particle size distribution, large surface area, and high crystallinity. This strategy for producing these nanostructures could lead to new compounds as novel alternative materials for biological applications. Lipase MG10 was successfully immobilized on the mentioned nanofibrous composites and biochemically characterized. The lipase activity of free and immobilized lipases was considered by measuring the absorbance of pNPP (500 µM in 40 mM Tris/HCl buffer, pH 7.8, and 0.01% Triton X100) at 37 °C for 30 min. Different concentrations of glutaraldehyde, different crosslinking times, different times of immobilization, different enzyme loading, and different pH values have been optimized. Results showed that the optimized immobilization condition was achieved in 2.5% glutaraldehyde, after 2 h of crosslinking time, after 6 h immobilization time, using 180 mg protein/g support at pH 9.0. The immobilized enzyme was also totally stable after 180 min incubation at 60 °C. The free enzyme showed the maximum activity at pH 9.0, but the optimal pH of the immobilized lipase was shifted about 1.5 pH units to the alkaline area. The immobilized lipase showed about 2.7 folds (78%) higher stability than the free enzyme at 50 °C. Some divalent metal ions, including Cu2+ (22%), Co2+ (37%), Mg2+ (12%), Hg2+ (11%), and Mn2+ (17%) enhanced the enzyme activity of immobilized enzyme. The maximum biodiesel production (27%) from R. communis oil was obtained after 18 h of incubation by lipase MG10. The immobilized lipase displayed high potency in biodiesel production, about 83% after 12 h of incubation. These results indicated the high potency of Zr-MOF/PVP nanofibrous composites for efficient lipase immobilization.


Asunto(s)
Enzimas Inmovilizadas , Lipasa/química , Nanofibras/química , Polímeros/química , Proteínas Bacterianas , Biocombustibles , Fenómenos Químicos , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Cinética , Lipasa/aislamiento & purificación , Nanofibras/ultraestructura , Nanoestructuras/química , Polivinilos/química , Pirrolidinas/química , Solventes/química , Análisis Espectral
17.
Appl Biochem Biotechnol ; 193(6): 2004-2027, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33538961

RESUMEN

Bacterial fibrinolytic proteases achieved more attention in the prevention and treatment of cardiovascular diseases, so purification, characterization, and activity enhancement are of prime importance. In this study, a fibrinolytic serine metalloprotease was purified from the culture supernatant from Bacillus sp. BC1. It was purified to homogeneity by a two-step procedure with a 24-fold increase in specific activity and a 33.1% yield. It showed 28 kDa molecular weight, while its optimal pH and temperature were obtained 8 and 50-60 °C. The cross-link enzyme aggregates of this fibrinolytic BC1 successfully immobilized on magnetic chitosan nanoparticles. A 52% activity enhancement was obtained by immobilized enzyme at pH 6.0, compared to free protease. Km values of the free and immobilized proteases were obtained about 0.638 and 0.61 mg/ml, respectively. The free and immobilized enzymes did not show any activity concerning transferrin, γ-globulins, and hemoglobin, as blood plasma proteins. The in vitro blood clot lysis test of the free and immobilized proteases showed a maximum of 42 and 50% clot lysis, which was comparatively higher than that revealed by streptokinase and heparin at the same condition. These results indicated that the free and immobilized proteases have the potential to be effective fibrinolytic agents.


Asunto(s)
Bacillus/enzimología , Proteínas Bacterianas/química , Quitosano/química , Enzimas Inmovilizadas/química , Fibrinolíticos/química , Nanopartículas/química , Péptido Hidrolasas/química , Agregado de Proteínas , Estabilidad de Enzimas , Humanos , Concentración de Iones de Hidrógeno , Fenómenos Magnéticos
18.
Colloids Surf B Biointerfaces ; 196: 111318, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32871443

RESUMEN

A protease from Bacillus sp. CHA410 was purified and immobilized by a one-step MOF-embedded approach. The immobilized protease characterized using transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The optimal pH activity of protease CHA410 and protease@MOF was obtained at pH 8.0 and 9.0, respectively. Thermostability results after 160 min incubation showed that a 25 and 41 % enhancement in the relative activity of protease@MOF observed at 60 and 70 °C, respectively, compared to free protease. Km of the free and immobilized protease@MOF in the presence of casein was 0.685 and 0.033 mg/mL, respectively. Also, Km of the free and immobilized protease@MOF in the presence of fibrin was 0.292 and 0.145 mg/mL, respectively. The Fibrinolytic activity/Caseinolytic activity ratio (F/C ratio) of the free and immobilized proteases was 0.36 and 0.43, respectively. Protease activity of both forms of the enzyme was increased in the presence of some divalent cations, including Ca2+, Mn2+, Mg2+, and Zn2+ ions, while it intensely diminished by phenylmethylsulfonyl fluoride (PMSF), proposed as serine-protease. A 10 and 82 % enhancement in protease activity of free and immobilized proteases was achieved in the presence of butanol, respectively. Storage stability results showed that the immobilized enzyme retained about 70 % of its original activity at the end of this period, while the free enzyme only showed 22 % of its initial activity. The hydrolysis degree of immobilized protease CHA410 in the hydrolysis of fish protein waste was obtained about 46 % after 2 h of incubation at 50 °C. In comparison, it was gained about 20 % for protease CHA410 at a similar situation. Finally, results indicated that the free and immobilized protease could be used in the food industry for the hydrolysis of fish protein waste.


Asunto(s)
Estructuras Metalorgánicas , Estabilidad de Enzimas , Enzimas Inmovilizadas/metabolismo , Proteínas de Peces , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , Péptido Hidrolasas , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
19.
Asian Pac J Cancer Prev ; 21(6): 1747-1753, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32592373

RESUMEN

BACKGROUND: Deregulation of the EGFR signaling pathway activity has been shown to can be effective in resistance to EGFR-TKIs, such as Tarceva (erlotinib), in glioblastoma cells. In addition, reports have shown that the reduction of miRNA-7 expression levels is associated with an increase in the expression of EGFR. Here, we evaluated the effect of miRNA-7 on EGFR expression and sensitivity of the U373-MG glioblastoma to erlotinib. METHODS: The effect of miRNA-7 on EGFR expression was examined using RT-qPCR and western blotting. Trypan blue and MTT assays were performed to explore the effect of treatments on cell growth and survival, respectively. The combination index analysis was used to evaluate the interaction between drugs. Apoptosis was measured by ELISA cell death assay. RESULTS: We showed that miRNA-7 markedly inhibited the expression of EGFR and decreased the growth of glioblastoma cells, relative to blank control and negative control miRNA (p < 0.05). Introduction of miRNA-7 synergistically increased the sensitivity of the U373-MG cells to erlotinib. Results of apoptosis assay demonstrated that miRNA-7 can trigger apoptosis and enhance the erlotinib-mediated apoptosis. CONCLUSIONS: Our results show that miRNA-7 plays a critical role in the growth, survival and sensitivity of the U373-MG cells to erlotinib by targeting EGFR. Thus, miRNA-7 replacement therapy can become an effective therapeutic procedure in glioblastoma.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular , Resistencia a Antineoplásicos/efectos de los fármacos , Clorhidrato de Erlotinib/farmacología , Glioblastoma/patología , MicroARNs/genética , Apoptosis , Ciclo Celular , Receptores ErbB/genética , Receptores ErbB/metabolismo , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Humanos , Células Tumorales Cultivadas
20.
J Biomed Mater Res B Appl Biomater ; 108(3): 717-728, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31187938

RESUMEN

The aim of the present study was to develop modified nanoemulsions to improve the oral bioavailability and pharmacokinetics of a poor water-soluble drug, repaglinide (RPG). The repaglinide-loaded nanoemulsions (RPG-NEs) were prepared from olive oil as internal phase, span 80, tween 80, and poloxamer 188 as emulsifiers, using homogenization technique. The mean droplet size, zeta potential, and entrapment efficiency of RPG-NEs were 86.5 ± 3.4 nm, -33.8 ± 2.1 mV, and 96.3 ± 2.3%, respectively. The chitosan-coated RPG-NEs (Cs-RPG-NEs) showed an average droplet size of 149.3 ± 3.9 nm and a positive zeta-potential of +31.5 ± 2.8 mV. Drug release profile of RPG-NEs was significantly higher than free drug in the simulated gastrointestinal fluids (p < .005). The in vivo study revealed 3.51- and 1.78-fold increase in the AUC0-12h and Cmax of the drug, respectively, in RPG-NEs-receiving animals in comparison to the free drug. The pharmacokinetic analysis confirmed that Cs-RPG-NEs were more efficient than uncoated ones for the oral delivery of RPG. Cs-RPG-NEs showed a longer t1/2 and higher AUC0-∞ compared to control group. The relative bioavailability of Cs-RPG-NEs was higher than that of uncoated RPG-NEs and free drug. Collectively, these findings suggest that chitosan-coated nanoemulsions are promising carrier for improving the oral bioavailability of RPG.


Asunto(s)
Carbamatos/química , Quitosano/química , Emulsiones/química , Hipoglucemiantes/química , Nanocápsulas/química , Piperidinas/química , Administración Oral , Animales , Disponibilidad Biológica , Carbamatos/administración & dosificación , Carbamatos/farmacocinética , Composición de Medicamentos , Liberación de Fármacos , Absorción Gastrointestinal/efectos de los fármacos , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/farmacocinética , Líquido Intracelular/metabolismo , Masculino , Piperidinas/administración & dosificación , Piperidinas/farmacocinética , Poloxámero , Polisorbatos , Ratas Sprague-Dawley , Solubilidad
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