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1.
Vaccine ; 42(7): 1831-1840, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-37479613

RESUMO

mRNA technology has emerged as a successful vaccine platform that offered a swift response to the COVID-19 pandemic. Accumulating evidence shows that vaccine efficacy, thermostability, and other important properties, are largely impacted by intrinsic properties of the mRNA molecule, such as RNA sequence and structure, both of which can be optimized. Designing mRNA sequence for vaccines presents a combinatorial problem due to an extremely large selection space. For instance, due to the degeneracy of the genetic code, there are over 10632 possible mRNA sequences that could encode the spike protein, the COVID-19 vaccines' target. Moreover, designing different elements of the mRNA sequence simultaneously against multiple objectives such as translational efficiency, reduced reactogenicity, and improved stability requires an efficient and sophisticated optimization strategy. Recently, there has been a growing interest in utilizing computational tools to redesign mRNA sequences to improve vaccine characteristics and expedite discovery timelines. In this review, we explore important biophysical features of mRNA to be considered for vaccine design and discuss how computational approaches can be applied to rapidly design mRNA sequences with desirable characteristics.


Assuntos
COVID-19 , Vacinas de mRNA , Humanos , Vacinas contra COVID-19 , Pandemias , COVID-19/prevenção & controle , RNA Mensageiro/genética
2.
J Pharmacopuncture ; 23(3): 158-164, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33072413

RESUMO

OBJECTIVES: The aim of the present work was to evaluate the possible beneficial effects of F. latisecta on blood glucose, lipids, and diabetes-related changes in the liver and kidney of streptozotocin-induced diabetic rats. METHODS: Male Wistar rats were randomly allocated into four groups (n = 6) normal control rats, diabetic control rats, diabetic rats treated for 4 weeks with F. latisecta root (400 mg/kg/day), and diabetic rats treated with F. latisecta aerial parts (400 mg/kg/day). RESULTS: Induction of diabetes significantly (p < 0.05) increased the levels of fasting blood glucose (FBG), triglyceride, total cholesterol, low-density lipoprotein (LDL), blood urea nitrogen (BUN), aspartate aminotransferase (AST), and alanine aminotransferase (ALT). Diabetes also increased (p < 0.05) oxidative stress in the kidney and liver (decrease of thiol and increase of superoxide dismutase). The root and aerial parts of F. latisecta significantly reduced the level of LDL (p < 0.05) and restored the content of thiol (p < 0.05) and superoxide dismutase (p < 0.01) in the kidney and liver. F. latisecta had no significant effect on the levels of FBG, BUN, AST, and ALT. The root of F. latisecta also reduced the serum level of total cholesterol (p < 0.05) and prevented the progression of hyperglycemia. CONCLUSION: These findings suggest that F. latisecta may improve diabetic dyslipidemia by reducing serum LDL. Further studies are needed to confirm our findings.

3.
ACS Appl Mater Interfaces ; 12(9): 10554-10562, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32026677

RESUMO

Pollution of water with heavy metals is a global environmental problem whose impact is especially severe in developing countries. Among water-purification methods, adsorption of heavy metals has proven to be simple, versatile, and cost-effective. However, there is still a need to develop adsorbents with a capacity to remove multiple metal pollutants from the same water sample. Herein, we report the complementary adsorption capacities of metal-organic frameworks (here, UiO-66 and UiO-66-(SH)2) and inorganic nanoparticles (iNPs; here, cerium-oxide NPs) into composite materials. These adsorbents, which are spherical microbeads generated in one step by continuous-flow spray-drying, efficiently and simultaneously remove multiple heavy metals from water, including As(III and V), Cd(II), Cr(III and VI), Cu(II), Pb(II), and Hg(II). We further show that these microbeads can be used as a packing material in a prototype of a continuous-flow water treatment system, in which they retain their metal-removal capacities upon regeneration with a gentle acidic treatment. As proof-of-concept, we evaluated these adsorbents for purification of laboratory water samples prepared to independently recapitulate each of two strongly polluted rivers: the Bone (Indonesia) and Buringanga (Bangladesh) rivers. In both cases, our microbeads reduced the levels of all the metal contaminants to below the corresponding permissible limits established by the World Health Organization (WHO). Moreover, we demonstrated the capacity of these microbeads to lower levels of Cr(VI) in a water sample collected from the Sarno River (Italy). Finally, to create adsorbents that could be magnetically recovered following their use in water purification, we extended our spray-drying technique to simultaneously incorporate two types of iNPs (CeO2 and Fe3O4) into UiO-66-(SH)2, obtaining CeO2/Fe3O4@UiO-66-(SH)2 microbeads that adsorb heavy metals and are magnetically responsive.

4.
Drug Chem Toxicol ; 43(6): 609-615, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31264488

RESUMO

Despite the widespread use of Rheum turkestanicum in herbal medicine, no study has yet examined its in vivo toxicity. The aim of this study is to evaluate the acute and sub-acute toxicity of hydroalcoholic extract of R. turkestanicum root. In acute toxicity experiment, female and male mice (n = 5/group/sex) were orally administrated with the extract at single doses of 300, 2000 and 3000 mg/kg and observed for 14 days. In the sub-acute study, the extract was orally administered daily at doses of 100 and 400 mg/kg to male rats (n = 8) for 4 weeks. During the acute toxicity test, there were no deaths or any signs of toxicity observed after administration of the R. turkestanicum extract at 300 mg/kg, which was the no-observed-adverse-effect level (NOAEL). The extract at a dose of 3000 mg/kg led to the death of one female and one male mouse (LD50 > 3000 mg/kg). In sub-acute toxicity experiment, the extract induced no mortality or significant changes in body weight, general behaviors, hematological parameters, serum biochemical factors (related to the kidney and liver function), and histopathology of the heart, liver, kidney, and brain up to the highest dose tested of 400 mg/kg (NOAEL). High-performance liquid chromatography-mass spectrometry revealed the presence of phenolic compounds, flavonoids, alkanes, and anthraquinones in the extract. In conclusion, short-term use of R. turkestanicum root does not appear to produce significant toxicity up to a dose of 400 mg/kg.


Assuntos
Extratos Vegetais/toxicidade , Raízes de Plantas/toxicidade , Rheum/toxicidade , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda , Administração Oral , Animais , Biomarcadores/sangue , Feminino , Dose Letal Mediana , Masculino , Camundongos , Nível de Efeito Adverso não Observado , Extratos Vegetais/administração & dosagem , Ratos Wistar , Medição de Risco , Fatores de Tempo
5.
Res Pharm Sci ; 14(2): 138-145, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31620190

RESUMO

Previous studies have shown that some plants in the genus of Ferula (Apiaceae) have antidiabetic effects. The present work was aimed to evaluate effects of Ferula gummosa oleo-resin in a rat model of streptozotocin-induced diabetes. Male Wistar rats were randomized into five groups (n = 6): normal control, diabetic control, diabetic rats treated with insulin (3 IU/day), and diabetic rats treated with 100 or 400 mg/kg/day of an ethanolic extract of the oleo-resin. After 4 weeks, blood samples were collected for measuring fasting blood glucose (FBG), lipid profile, aspartate aminotransferase, alanine aminotransferase (ALT), alkaline phosphatase, blood urea nitrogen, and creatinine. In addition, levels of lipid peroxidation, thiol groups, and superoxide dismutase (SOD) activity were evaluated in the liver and kidney. At the end of the fourth week, the level of FBG in rats treated with 100 mg/kg of the extract was lower than that in diabetic control rats (273 ± 39 mg/dL vs 471 ± 32 mg/dL). Administration of insulin and the extract had no significant effects on the serum lipids. Insulin and both doses of the extract significantly reduced the activity of ALT. In addition, the extract inhibited lipid peroxidation in the kidney and restored the elevated level of SOD in the liver and kidneys. Ferula gummosa oleo-resin has the potential to prevent or delay the complications of diabetes by inhibiting the progression of hyperglycemia and attenuating oxidative stress-induced damage in the liver and kidneys.

6.
Angew Chem Int Ed Engl ; 58(28): 9512-9516, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31087600

RESUMO

Herein, we describe a new class of porous composites comprising metal-organic framework (MOF) crystals confined in single spherical matrices made of packed covalent-organic framework (COF) nanocrystals. These MOF@COF composites are synthesized through a two-step method of spray-drying and subsequent amorphous (imine-based polymer)-to-crystalline (imine-based COF) transformation. This transformation around the MOF crystals generates micro- and mesopores at the MOF/COF interface that provide far superior porosity compared to that of the constituent MOF and COF components added together. We report that water sorption in these new pores occurs within the same pressure window as in the COF pores. Our new MOF@COF composites, with their additional pores at the MOF/COF interface, should have implications for the development of new composites.

7.
ACS Appl Mater Interfaces ; 10(28): 23952-23960, 2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-29931972

RESUMO

Here, we report the synthesis of (multi)-layered zeolitic imidazolate framework (ZIF-8/-67) composite particles via a sequential deconstruction-reconstruction process. We show that this process can be applied to construct ZIF-8-on-ZIF-67 composite particles whose cores are the initially etched particles. In addition, we demonstrate that introduction of functional inorganic nanoparticles (INPs) onto the crystal surface of etched particles does not disrupt ZIF particle reconstruction, opening new avenues for designing (multi)-layered ZIF-on-INP-on-ZIF composite particles comprising more than one class of inorganic nanoparticles. In these latter composites, the location of the inorganic nanoparticles inside each single metal-organic framework particle as well as of their separation at the nanoscale (20 nm) is controlled. Preliminary results show that (multi)-layered ZIF-on-INP-on-ZIF composite particles comprising a good sequence of inorganic nanoparticles can potentially catalyze cascade reactions.

8.
Biomed J ; 41(6): 340-347, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30709575

RESUMO

BACKGROUND: Due to antioxidant effects of Zataria multiflora (ZM) and Carvacrol (CAR) in many cases and the prominent role of reactive oxygen species (ROS) in hepatotoxicity induced by Adriamycin (ADR), the aim of this study is to investigate the effects of ZM and CAR on ADR-induced hepatotoxicity. METHODS: Twenty four male Wistar rats were randomly divided into four groups including: 1)Control, 2)Adriamycin (ADR), 3,4) ZM + ADR and CAR + ADR that received ZM and CAR for 28 consecutive days. Blood samples were collected on the days 0, 14 and 28 to determine the alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. Also, the hepatic redox markers were evaluated. RESULTS: ADR significantly increased ALP, ALT and AST in comparison with the control (p < 0.05 - p < 0.001). In CAR + ADR group, the serum ALP, ALT and AST were significantly reduced compared to those of the ADR group (p < 0.01 to p < 0.001). Also, in ZM + ADR group, serum ALP and ALT compared to ADR was significantly reduced (p < 0.001). MDA level in the ADR group significantly increased compared to control (p < 0.01). The MDA level in ZM + ADR (p < 0.05) and CAR + ADR (p < 0.01) groups were significantly reduced compared to that of ADR. Thiol levels in ZM + ADR group significantly increased compared to the ADR group (p < 0.05). The activities of CAT in the ADR group was significantly reduced compared to control (p < 0.05) and increased in treatment groups in comparison with the ADR (p < 0.01). CONCLUSION: Long-term administration of ZM extract and CAR could reduce the oxidative damage in the rat liver induced by ADR through the strengthening of the antioxidant system.


Assuntos
Antioxidantes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Lamiaceae/química , Monoterpenos/farmacologia , Extratos Vegetais/farmacologia , Animais , Cimenos , Modelos Animais de Doenças , Doxorrubicina/farmacologia , Fígado/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar
9.
Chemistry ; 23(36): 8623-8627, 2017 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28508592

RESUMO

Here, a two-step method is reported that enables imparting new functionalities to covalent organic frameworks (COFs) by nanoparticle confinement. The direct reaction between 1,3,5-tris(4-aminophenyl)benzene and 1,3,5-benzenetricarbaldehyde in the presence of a variety of metallic/metal-oxide nanoparticles resulted in embedding of the nanoparticles in amorphous and non-porous imine-linked polymer organic spheres (NP@a-1). Post-treatment reactions of NP@a-1 with acetic acid under reflux led to crystalline and porous imine-based COF-hybrid spheres (NP@c-1). Interestingly, Au@c-1 and Pd@c-1 were found to be catalytically active.

10.
Chemistry ; 23(28): 6829-6835, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28370527

RESUMO

Metal-organic frameworks (MOFs) built up from connecting M-XF6 pillars through N-donor ligands are among the most attractive adsorbents and separating agents for CO2 and hydrocarbons today. The continuous, one-step spray-drying synthesis of several members of this isoreticular MOF family varying the anionic pillar (XF6 =[SiF6 ]2- and [TiF6 ]2- ), the N-donor organic ligand (pyrazine and 4,4'-bipyridine) and the metal ion (M=Co, Cu and Zn) is demonstrated here. This synthetic method allows them to be obtained in the form of spherical superstructures assembled from nanosized crystals. As confirmed by CO2 and N2 sorption studies, most of the M-XF6 -based MOFs synthesised through spray-drying can be considered "ready-to-use" sorbents as they do not need additional purification and time consuming solvent exchange steps to show comparable porosity and sorption properties with the bulk/single-crystal analogues. Stability tests of nanosized M-SiF6 -based MOFs confirm their low stability in most solvents, including water and DMF, highlighting the importance of protecting them once synthesised. Finally, for the first time it was shown that the spray-drying method can also be used to assemble hydrogen-bonded open networks, as evidenced by the synthesis of MPM-1-TIFSIX.

11.
Chemistry ; 21(6): 2508-18, 2015 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-25504892

RESUMO

Metal-organic frameworks (MOFs) are among the most attractive porous materials available today. They have garnered much attention for their potential utility in many different areas such as gas storage, separation, catalysis, and biomedicine. However, very little is known about the possible health or environmental risks of these materials. Here, the results of toxicity studies on sixteen representative uncoated MOF nanoparticles (nanoMOFs), which were assessed for cytotoxicity to HepG2 and MCF7 cells in vitro, and for toxicity to zebrafish embryos in vivo, are reported. Interestingly, there is a strong correlation between their in vitro toxicity and their in vivo toxicity. NanoMOFs were ranked according to their respective in vivo toxicity (in terms of the amount and severity of phenotypic changes observed in the treated zebrafish embryos), which varied widely. Altogether these results show different levels of toxicity of these materials; however, leaching of solubilized metal ions plays a main role.

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