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1.
Rev Med Virol ; 34(4): e2556, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38853706

RESUMO

Stroke is a common worldwide cause of death and disability, resulting from an obstruction or reduction in blood flow to the brain. Research has demonstrated that systemic infection such as herpes zoster (HZ) / ophthalmicus herpes zoster (HZO) can potentially trigger stroke. This study includes an updated systematic review and meta-analysis of the epidemiologic data on the connection between HZ/HZO infection and the risk of stroke. A meticulous search of different database yielded 905 studies. Furthermore, an additional 14 studies from a previous meta-analysis were incorporated. Eligible studies underwent rigorous screening, resulting in 18 papers. Statistical analyses, including random/fixed effects models and subgroup analyses, were conducted to assess pooled relative risk (RR) and heterogeneity. The meta-analysis consisted of 5,505,885 participants and found a statistically significant association between HZ infection and the risk of stroke (pooled RR = 1.22, 95% confidence interval [CI] 1.12-1.34). The HZO infection showed a significantly higher overall pooled RR of 1.71 (95% CI 1.06-2.75), indicating a strong connection with the risk of stroke. Subgroup analysis revealed that the odds ratio might play a significant role in causing heterogeneity. Time since infection emerged as a crucial factor, with heightened stroke risk in the initial year post-HZ/HZO exposure, followed by a decline after the first year. Asian/Non-Asian studies demonstrated varied results in HZ/HZO patients. Meta-analysis reveals a significant HZ/HZO-stroke link. Subgroups highlight varied risks and warrant extended Asian/non-Asian patient investigation.


Assuntos
Herpes Zoster , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/virologia , Herpes Zoster/epidemiologia , Herpes Zoster/virologia , Herpes Zoster/complicações , Medição de Risco , Fatores de Risco , Herpesvirus Humano 3
2.
Helicobacter ; 29(2): e13067, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38514932

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) is a rod-shaped, gram-negative, microaerophilic bacterium that can be identified by gram staining. Its relationship with cancer is significant since it is involved in approximately 80% of gastric cancers and 5.5% of all malignant cancers. Two lines of treatment have been defined for H. pylori, but almost 40% of patients do not respond to the first line. Recent trials have investigated oral Immunotherapy as a new treatment method. The aim of this systematic review was to investigate the potential effects of oral Immunotherapy on eradication rate of H. pylori in human studies. METHODS: The systematic review was performed according to PRISMA guidelines. We searched online databases, including Scopus, PubMed, and Web of Science (ISI). Our search strategy was limited to English articles and studies on human populations that use oral immunotherapy for H. pylori. RESULTS: The total number of primary research records in different databases was 2775. After removing duplicate articles (n = 870), we excluded 1829 for reasons including non-human studies, irrelevance to our study objective, non-English language, or lack of information. Of the remaining 76 articles, only seven had sufficient information, and the rest were excluded. The studies were divided into two groups: those that used bovine antibody and those that used immunoglobulin Y to eradicate H. pylori. CONCLUSION: In the group of Immunoglobulin Y, three out of four studies suggest that using Immunoglobulin Y for the treatment of H. pylori infection is significant. However, the group using bovine antibody for the treatment of H. pylori infection has various results, as two out of three studies concluded that bovine antibody therapy is not significant.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Imunoterapia , Humanos , Infecções por Helicobacter/terapia , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Imunoterapia/métodos , Administração Oral , Animais
3.
Inorg Chem ; 63(3): 1652-1673, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38194483

RESUMO

We synthesized a stable and reusable Schiff base complex of copper immobilized on core-shell magnetic nanoparticles [Cu(II)-SB/GPTMS@SiO2@Fe3O4] with simple, efficient, and available materials. A variety of characterization analyses including Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA), X-ray diffraction (XRD), vibrating-sample magnetometry (VSM), energy-dispersive X-ray spectrometry (EDX), and inductively coupled plasma (ICP) confirm that our synthesized nanocatalyst was obtained. The particle size distribution from the TEM image was obtained in the range of 42-55 nm. The existence of cupric species (Cu2+) in the catalyst was determined with XPS analysis and clearly indicated two peaks at 933.7 and 953.7 eV for Cu 2p3/2 and Cu 2p1/2, respectively. BET results showed that our catalyst synthesized with a mesoporous structure and with a specific area of 48.82 m2 g-1. After detailed characterization, the resulting nanocatalyst exhibited excellent catalytic performance for the explored catalytic reactions in the one-pot synthesis of polyhydroquinoline derivatives by the Hantzsch reaction of dimedone, ethyl acetoacetate, ammonium acetate, and various aldehydes under sustainable and mild conditions. The corresponding products 5a-l are achieved in yields of 88-97%. Additionally, density functional theory (DFT) calculations were carried out to investigate the electrostatic potential root (ESP), natural bond orbital (NBO), and molecular orbitals (MOs), drawing the reaction mechanism using the total energy of the reactant and product and the study of structural parameters.

4.
Phys Chem Chem Phys ; 26(6): 5262-5288, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38264800

RESUMO

Nanomaterials-based gas sensors are widely applied for the monitoring and fast detection of hazardous gases owing to their sensitivity and selectivity. Hydrogen sulfide (H2S), hydrogen fluoride (HF), ammonia (NH3), and carbon monoxide/dioxide (CO/CO2) produced from petroleum fields, sewage, mines, and gasoline are harmful for both human life and environment. With an increase in the emission of these toxic compounds, their real-time monitoring and efficient adsorbent application and storage are very necessary. To this end, we investigated the adsorption characteristic and sensitivity factor of these five toxic gases on armchair and zigzag hybrid boron-carbon-nitride (BCN) nanoribbons with/without boron-rich (B-rich) defects using first principle calculation, where 25%, 33%, and 50% carbon concentration were considered. Our findings reveal that B-rich nanoribbons have strong adsorption energy, charge transfer, and structural deformation owing to the double acceptor of B-rich defects. Moreover, the zigzag and armchair forms of these hybrid BCN nanoribbons show physical adsorption, altering their band gap and phase transition after adsorbing these toxic gases, where B-rich nanoribbons possess high sensitivity to NH3 and CO among other gases. Furthermore, B-rich hybrid nanoribbons have higher CO2 adsorption energy than the standard free energy of CO2 at room temperature. This study suggests that hybrid BCN nanoribbons and B-rich defected structures can be good candidates for the uptake and storage of toxic gases, helping experimental groups to design efficient ambient gas sensors.

5.
Mol Divers ; 27(1): 249-261, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35438428

RESUMO

Caspases (cysteine-aspartic proteases) play critical roles in inflammation and the programming of cell death in the form of necroptosis, apoptosis, and pyroptosis. The name of these enzymes has been chosen in accordance with their cysteine protease activity. They act as cysteines in nucleophilically active sites to attack and cleave target proteins in the aspartic acid and amino acid C-terminal. Based on the substrate's structure and the specificity, the physiological activity of caspases is divided. However, in apoptosis, the division of caspases into initiating caspases (caspase 2, 8, 9, and 10) and executive caspases (caspase 3, 6, and 7) is essential. The present study aimed to perform Proteochemometrics Modeling to generalize the data on caspases, which could predict ligand and protein interactions. In this study, we employed protein and ligand descriptors. Moreover, protein descriptors were computed using the Protr R package, while PADEL-Descriptor was employed for the computation of ligand descriptors. In addition, NCA (Neighborhood Component Analyses) was used for descriptor selection, and SVR, decision tree, and ensemble methods were utilized for the proteochemometrics modeling. This study shows that the ensemble model demonstrates superior performance compared with other models in terms of R2, Q2, and RMSE criteria.


Assuntos
Apoptose , Caspases , Caspases/química , Caspases/metabolismo , Ligantes , Isoformas de Proteínas , Domínio Catalítico
6.
Exp Parasitol ; 244: 108426, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36400251

RESUMO

OBJECTIVES: This study aimed to determine feeding behaviors of Phlebotomus sergenti Parrot, in a new focus of Anthroponotic Cutaneous Leishmaniasis in Bam County, southeast Iran. METHODS: Two methods were used to determine the feeding behavior of Phlebotomus sergenti. In the first method, blood-fed sand flies were captured using a mouth aspirator in human and animal dwellings and consequently, blood meal identification was made using Multiplex PCR. The results were used for calculating Host Feeding Index (HFI) and Forage Ratio (FR) parameters. In the second method, human (Homo sapiens), goat (Capra aegagrus), cattle (Bos taurus), chicken (Gallus gallus) and dog (Canis lupus) were used as baits in tent-baited traps to determine the feeding behavior of Phlebotomus sergenti. RESULTS: Multiplex PCR analysis revealed that the most frequent blood in the stomack of sand flies' were from chicken, but the calculation of the FR revealed that this species prefers canine and poultary blood as meal. Human and animal tent-baited traps revealed that most Phlebotomus sergenti were attracted to chicken rather than the other hosts. CONCLUSIONS: Sand flies are attracted to animals for various reasons such as eating blood, mating on their bodies and laying eggs on their feces. Molecular methods are effective and accurate methods to determine the type of host that sandfly fed on, but they do not show host preferences. The results of the molecular analysis, along with the calculation of HFI and FR, can determine the preferred host of sand flies. The current study revealed that dogs, the secondary reservoir of ACL in Iran, is the first preferred host of Phlebotomus sergenti.


Assuntos
Leishmaniose Cutânea , Phlebotomus , Psychodidae , Humanos , Cães , Animais , Bovinos , Reação em Cadeia da Polimerase Multiplex , Irã (Geográfico) , Comportamento Alimentar
7.
Inorg Chem ; 61(2): 992-1010, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34962386

RESUMO

An efficient and heterogeneous novel magnetic silica-coated picolylaminecopper complex [Fe3O4@SiO2@GP/Picolylamine-Cu(II)] was synthesized, characterized, and employed as a magnetically recoverable nanocatalyst in Biginelli condensation for the preparation of biologically active 3,4-dihydropyrimidinones. Fe3O4@SiO2@GP/Picolylamine-Cu(II) was synthesized easily using chemical attachment of the picolylaminecompound on Fe3O4@SiO2@GP, followed by treatment with copper salt in ethanol under reflux conditions. Fe3O4@SiO2@GP/Picolylamine-Cu(II) was affirmed by various analyses such as Fourier transform infrared, thermogravimetric analysis, X-ray diffraction, vibrating-sample magnetometry, field-emission scanning electron microscopy, transmission electron microscopy, DLS, inductively coupled plasma, energy-dispersive X-ray spectrometry, X-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller. The resulting catalyst system was successfully used in the Biginelli reaction through a variety of compounds such as aromatic aldehyde, urea, and ethyl acetoacetate under solvent-free conditions or ethylene glycol at 80 °C and yielded the desired products with high conversions with powerful reusability. The current approach was convenient and clean, and only 0.01 g of the catalyst could be used to perform the reaction. The easy work-up procedure, gram-scale synthesis, usage of nontoxic solvent, improved yield, short reaction times, and high durability of the catalyst are several remarkable advantages of the current approach. Also, the Fe3O4@SiO2@GP/Picolylamine-Cu(II) nanocatalyst could be recycled by an external magnet for eight runs with only a significant loss in the product yields.

8.
Inorg Chem ; 61(33): 13125-13132, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35946902

RESUMO

To study the influence of pore structural properties of metal-organic frameworks (MOFs) on drug adsorption and delivery, we synthesized two MOF termed TMU-6(RL1) {[Zn(oba)(RL1)0.5]n·(DMF)1.5} and TMU-21(RL2) {[Zn(oba)(RL2)0.5]n·(DMF)1.5} with amine basic N-donor pillars containing phenyl or naphthyl cores with various hydrophilic properties around the main center of the reaction. TG, IR, XPS, and PXRD analyses were used to extensively characterize the MOFs. The synthesized carriers showed high adsorption efficiency, stability, and controlled release. As an anticancer drug, Nimesulide (Nim) was adsorbed to MOFs using multiple adsorption mechanisms, such as Hostπ-πGuest interaction and HostN-H···OGuest hydrogen bonds. Moreover, Hirshfeld surface analysis showed when the benzene core was replaced with the naphthalene core, the percentage of intermolecular interactions of π···π and N···H by amine sites in TMU-21(RL2) decreased compared with TMU-6(RL1), while the percentage of these interactions with guest molecules increased. The results showed that changes in the hydrophobicity/hydrophilicity properties of MOFs would alter their ability to adsorb Nim in the pore of the frameworks. In vitro anticancer studies also showed that the cytotoxicity of Nim in MOFs@Nim composites against human cervical cancer cell line (HeLa cells) and human colon cancer cell line (HT-29 cells) is much higher than that of free Nim. Generally, based on the results, it can be said that the biological behavior of carriers can be regulated by adjusting the structure properties of MOFs.


Assuntos
Estruturas Metalorgânicas , Aminas , Sistemas de Liberação de Medicamentos/métodos , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia
9.
Clin Exp Pharmacol Physiol ; 49(9): 1010-1026, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35717592

RESUMO

Coumarins and their derivatives are becoming a potential source for new drug discovery due to their vast array of biological activities. The present study was designed to investigate the cardioprotective effects of a newly synthesised coumarin, symbolised as 5,6-PhSHC, against cardiac remodelling process in isoproterenol (ISO) induced myocardial infarction (MI) in male Wistar rats by evaluating haematological, biochemical and cardiac biomarkers. Rats were pre/co-treated with 5,6-PhSHC or clopidogrel (150 µg/kg body weight) daily for a period of 7 days and then MI was induced by injecting ISO (85 mg/kg body weight), at an interval of 24 hours for 2 consecutive days, on the sixth and seventh days. The in vivo exploration indicated that the injection of 5,6-PhSHC improved the electrocardiographic (ECG) pattern and prevented severe heart damage by reducing leakage of the cardiac injury markers, such as troponin-T (cTn-T), lactate dehydrogenase (LDH), and creatine kinase-MB. The cellular architecture of cardiac sections, altered in the myocardium of infracted rats, was reversed by 5,6-PhSHC treatment. Results showed that injection of 5,6-PhSHC elicited significant cardioprotective effects by prevention of myocardium cell necrosis and inflammatory cells infiltration, along with marked decrease in plasma levels of fibrinogen. In addition, the total cholesterol, triglyceride, LDL-c, and HDL profiles underwent remarkable beneficial changes. It was also interesting to note that 5,6-PhSHC enhanced the antioxidative defence mechanisms by increasing myocardial glutathione (GSH) level, superoxide dismutase (SOD), and catalase (CAT) activities, together with reducing the levels of thiobarbituric-acid-reactive substances (TBARS), when compared with ISO-induced rats. Taken together, these findings suggested a beneficial role for 5,6-PhSHC against ISO-induced MI in rats. Furthermore, in silico analysis showed that 5,6-PhSHC possess high computational affinities (E-value >-9.0 kcal/mol) against cyclooxygenase-2 (PDB-ID: 1CX2), vitamin K epoxide reductase (PDB-ID: 3KP9), glycoprotein-IIb/IIIa (PDB-ID: 2VDM) and catalase (PDB-ID: 1DGF). Therefore, the present study provided promising data that the newly synthesised coumarin can be useful in the design and synthesis of novel drug against myocardial infarction.


Assuntos
Infarto do Miocárdio , Animais , Antioxidantes/metabolismo , Peso Corporal , Cardiotônicos/efeitos adversos , Catalase/metabolismo , Cumarínicos/farmacologia , Cumarínicos/uso terapêutico , Eletrocardiografia , Glutationa/metabolismo , Isoproterenol/efeitos adversos , Masculino , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/prevenção & controle , Miocárdio/metabolismo , Estresse Oxidativo , Ratos , Ratos Wistar
10.
J Appl Toxicol ; 42(3): 506-515, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34551125

RESUMO

Although graphene oxide (GO) nanosheets are widely used in different fields, the mechanism of their toxicity remains relatively unknown. NMR-based metabolomics was used to study in vivo time and dose-dependent toxicity of GO nanosheets in mice. Sixty serum samples from mice in four different time intervals including 24 and 72 h and 7 and 21 days after injection of 0-, 1-, and 10-mg/kg b.w. were analyzed based on 1 HNMR spectra of each sample and multivariate methods. In comparison with the control group, 12 changed metabolites were identified in GO nanosheet-treated mice groups. These metabolites are involved in steroid hormone biosynthesis and steroid biosynthesis pathways. It was seen that the time factor is more important than the dose factor and the groups were separated in a time direction, completely. We found that GO nanosheets has toxicity and can affect steroidal hormones. However, this study shows that after 21 days, the treated groups regardless of their GO nanosheet dose are very close to the control group. This means that in one step exposure to GO nanosheets, their toxicity diminished after 21 days.


Assuntos
Grafite/toxicidade , Metabolômica/instrumentação , Nanoestruturas/toxicidade , Testes de Toxicidade , Animais , Masculino , Camundongos , Distribuição Aleatória
11.
Inorg Chem ; 60(17): 13588-13595, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34435495

RESUMO

This study has developed a specific, easy, and novel approach to designing a sacrificial metal-organic framework (MOF) that can detect and measure the amount of Hg2+ in aqueous and nonaqueous solutions using the naked eye. The functionalized [Zn(oba)(RL3)0.5]n·1.5DMF (TMU-59) provides the ability of simple visual assessment or colorimetric readout without sophisticated analytical equipment. Because of the special interaction with Hg2+, degradation of the structure of this unique MOF causes the solution to change color from colorless to a pink that is easily recognizable to the naked eye. The presence of a methyl group plays a major role in naked-eye detection by a qualitative sensor. Furthermore, this qualitative sensor data for the production of a simple, instant, and portable red, green, and blue (RGB)-based quantitative sensor were used to determine the concentration of Hg2+ in different specimens. As a turn-off fluorescence sensor, this unique structure is also capable of detecting Hg2+ at very low concentrations (the limit of detection is 0.16 ppb). To the best of our knowledge, TMU-59 is the first MOF-based naked-eye sensor that can successfully and specifically display the presence of Hg2+ through a major color change.

12.
Inorg Chem ; 60(19): 15010-15023, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34533947

RESUMO

A novel catalyst has been afforded by attaching of a Cu(proline)2 complex to magnetic nanoparticles through cheap, simple, and readily available chemicals. This catalyst was characterized by Fourier transform infrared, energy-dispersive X-ray, X-ray diffraction, vibrating-sample magnetometry, transmission electron microscopy, scanning electron microscopy, and inductively coupled plasma analyses. The catalytic activity of the Fe3O4@NH2@TCT@HProCu nanocatalyst was investigated in a green and effective synthesis of pyran derivatives in high yields by applying three-component reactions of malononitrile, dimedone, and aldehydes in ethanol. Conversion was high under optimal conditions. The obtained nanocatalyst could be easily separated from the mixture of the reaction and was recyclable nine times via a simple magnet without considerable reduction of its catalytic efficiency. Operational simplicity, high product yields, environmental friendliness, ecofriendliness, economical processing, and easy workup are the features of this methodology.


Assuntos
Complexos de Coordenação/química , Cobre/química , Hidroxiprolina/química , Nanopartículas de Magnetita/química , Piranos/síntese química , Catálise , Complexos de Coordenação/síntese química , Ciclização , Estrutura Molecular , Piranos/química
13.
Bioorg Chem ; 110: 104750, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33691251

RESUMO

A new serise of 7-hydroxy-chromone derivatives bearing pyridine moiety were synthesized, and evaluated as multifunctional agents against Alzheimer's disease (AD). Most of the compounds were good AChE inhibitors (IC50 = 9.8-0.71 µM) and showed remarkable BuChE inhibition activity (IC50 = 1.9-0.006 µM) compared with donepezil as the standard drug (IC50 = 0.023 and 3.4 µM). Compounds 14 and 10 showed the best inhibitory activity toward AChE (IC50 = 0.71 µM) and BuChE (IC50 = 0.006 µM), respectively. The ligand-protein docking simulations and kinetic studies revealed that compound 14 and 10 could bind effectively to the peripheral anionic binding site (PAS) of the AChE and BuChE through mixed-type inhibition. In addition, the most potent compounds showed acceptable neuroprotective activity on H2O2- and Aß-induced .neurotoxicity in PC12 cells, more than standard drugs. The compounds could block effectively self- and AChE-induced Aß aggregation. All the results suggest that compounds 14 and 10 could be considered as promising multi-target-directed ligands against AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Cromonas/farmacologia , Desenho de Fármacos , Compostos de Piridínio/farmacologia , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Animais , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Cromonas/síntese química , Relação Dose-Resposta a Droga , Peróxido de Hidrogênio , Ligantes , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Células PC12 , Farmacocinética , Conformação Proteica , Compostos de Piridínio/química , Ratos
14.
Pharm Dev Technol ; 26(8): 807-823, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34190000

RESUMO

Malaria, as one of the most common human infectious diseases, remains the greatest global health concern, since approximately 3.5 billion people around the world, especially those in subtropical areas, are at the risk of being infected by malaria. Due to the emergence and spread of drug resistance to the current antimalarials, malaria-related mortality and incidence rates have recently increased. To overcome the aforementioned obstacles, nano-vehicles based on biodegradable, natural, and non-toxic polymers have been developed. Accordingly, these systems are considered as a potential drug vehicle, which due to their unique properties such as the excellent safety profile, good biocompatibility, tunable structure, diversity, and the presence of functional groups within the polymer structure, could facilitate covalent attachment of targeting moieties and antimalarials to the polymeric nano-vehicles. In this review, we highlighted some recent developments of liposomes as unique nanoscale drug delivery vehicles and several polymeric nanovehicles, including hydrogels, dendrimers, self-assembled micelles, and polymer-drug conjugates for the effective delivery of antimalarials.


Assuntos
Antimaláricos/uso terapêutico , Portadores de Fármacos , Malária/tratamento farmacológico , Nanotecnologia/métodos , Antimaláricos/administração & dosagem , Resistência a Medicamentos , Humanos
15.
Nanotechnology ; 31(3): 035705, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31557735

RESUMO

Reverse nonequilibrium molecular dynamics (RNEMD) is employed to study the phononic thermal transport properties of C3N nanotubes. We study the effect of nanotube length and diameter on the thermal conductivity and investigate the phonon transport transition from ballistic to diffusive regime in C3N nanotubes. It is found that the thermal conductivity of C3N nanotubes is significantly lower than those of carbon nanotubes across the entire ballistic-diffusive range. In addition, significantly lower ballistic to diffusive transition length (72-80 nm) is observed in C3N nanotubes compared to carbon nanotubes. The inspection of phonon dispersion curves shows that carbon nanotubes have stiffer acoustic modes than C3N nanotubes which results in lower group velocities for C3N nanotubes. Due to the presence of nitrogen atoms, the phonon mean free paths and relaxation times of C3N nanotubes are shorter than those of the carbon nanotubes. The combined effect of lower group velocities and relaxation times leads to the lower thermal conductivity of C3N nanotubes.

16.
Bioorg Med Chem ; 27(13): 2914-2922, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31128990

RESUMO

Novel 4-oxobenzo[d]1,2,3-triazin derivatives bearing pyridinium moiety 6a-q were synthesized and screened against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Most of the synthesized compounds showed good inhibitory activity against AChE. Among the synthesized compounds, the compound 6j exhibited the highest AChE inhibitory activity. It should be noted that these compounds displayed low anti-BuChE activity with the exception of the compound 6i, as it exhibited BuChE inhibitory activity more than donepezil. The kinetic study of the compound 6j revealed that this compound inhibited AChE in a mixed-type inhibition mode. This finding was also confirmed by the docking study. The latter study demonstrated that the compound 6j interacted with both the catalytic site and peripheral anionic site of the AChE active site. The compound 6j was also observed to have significant neuroprotective activity against H2O2-induced PC12 oxidative stress, but low activity against ß-secretase.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Piridinas/síntese química , Humanos , Fármacos Neuroprotetores/farmacologia , Piridinas/química
17.
Phytother Res ; 32(9): 1795-1802, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29748995

RESUMO

Due to the challenges in the control, prevention, and eradication of parasitic diseases like malaria, there is an urgent need to discover new therapeutic agents. Plant-derived medicines may open new ways in the field of antiplasmodial therapy. This study is aimed to investigate the toxicity and in vivo antiplasmodial activity of apigenin, a dietary flavonoid. Apigenin cytotoxicity was investigated on Huh7 cell line, brine shrimp (Artemia salina) larva, and human red blood cells. In vivo toxicity of apigenin was assessed by metabolomics approaches. Apigenin exhibited significant suppression of parasitemia in a dose-dependent manner; it suppressed Plasmodium berghei growth by 69.74%, 50.3%, and 49.23% at concentrations of 70, 35, and 15 mg/kg/day, respectively. The IC50 value for apigenin after 24 hr exposure to Huh7 cells was 225 µg/ml. Apigenin did not show noticeable toxicity on A. salina and also on the membrane integrity of red blood cells. After 24 hr exposure of mice to apigenin, alterations were seen in the metabolism of glucocorticoids and mineralocorticoids, bile acid metabolism (alternative pathway), sulfur metabolism, bile acid metabolism, metabolism of estrogens and androgens, cholesterol catabolism, and biosynthesis of cholesterol. These findings indicate that apigenin has potential in vivo antiplasmodial activity against P. berghei infected mice with high selectivity against malaria, but it can disrupt some metabolic pathways in mice.


Assuntos
Antimaláricos/farmacologia , Apigenina/farmacologia , Malária/tratamento farmacológico , Plasmodium berghei/efeitos dos fármacos , Animais , Artemia/efeitos dos fármacos , Linhagem Celular , Eritrócitos/efeitos dos fármacos , Humanos , Masculino , Redes e Vias Metabólicas , Metaboloma , Camundongos , Plantas Medicinais/efeitos dos fármacos , Testes de Toxicidade
18.
Pharm Dev Technol ; 23(9): 911-920, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28851256

RESUMO

PURPOSE: Artemisinin (ART) has anti-inflammatory, antimicrobial, antioxidant, anti-amyloid, and anti-malarial effects, but its application is limited due to its low water solubility and poor oral bioavailability. In this study, the bioavailability, water solubility, and anti-plasmodial property of ART were improved by PCL-PEG-PCL tri-block copolymers. METHODS: The structure of the copolymers was characterized by 1H NMR, FT-IR, DSC, and GPC techniques. ART was encapsulated within micelles by a single-step nano-precipitation method, leading to the formation of ART-loaded PCL-PEG-PCL micelles. The obtained micelles were characterized by dynamic light scattering (DLS) and atomic force microscopy (AFM). The in vivo anti-plasmodial activity of ART-loaded micelles was measured against Plasmodium berghei infected Swiss albino mice. RESULTS: The results showed that the zeta potential of ART-loaded micelles was about -8.37 mV and the average size was 91.87 nm. ART was encapsulated into PCL-PEG-PCL micelles with a loading capacity of 19.33 ± 0.015% and encapsulation efficacy of 87.21 ± 3.32%. In vivo anti-plasmodial results against P. berghei showed that multiple injections of ART-loaded micelles could prolong the circulation time and increase the therapeutic efficacy of ART. CONCLUSION: These results suggested that PCL-PEG-PCL micelles would be a potential carrier for ART for the treatment of malaria.


Assuntos
Anti-Infecciosos/administração & dosagem , Portadores de Fármacos/administração & dosagem , Malária/tratamento farmacológico , Nanopartículas/administração & dosagem , Plasmodium berghei/efeitos dos fármacos , Poliésteres/administração & dosagem , Polietilenoglicóis/administração & dosagem , Animais , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacocinética , Artemisininas/síntese química , Artemisininas/farmacocinética , Portadores de Fármacos/síntese química , Portadores de Fármacos/farmacocinética , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Malária/metabolismo , Camundongos , Nanopartículas/química , Nanopartículas/metabolismo , Plasmodium berghei/fisiologia , Poliésteres/síntese química , Poliésteres/farmacocinética , Polietilenoglicóis/síntese química , Polietilenoglicóis/farmacocinética
19.
Toxicol Mech Methods ; 28(7): 539-546, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29708463

RESUMO

Quantum dots (QDs) have widespread application in many fields such as medicine and electronics. The need for understanding the potentially harmful side effects of these materials becomes clear. In this study, the toxicity of cadmium telluride quantum dots (CdTe-QDs) and bulk Cd2+ has been investigated and compared by applying metabolomics methods. The datasets were 1H-NMR data from mice plasma which had been taken from four groups of mice in different time intervals. Then, the data were analyzed by applying chemometrics methods and the metabolites were found from Human Metabolome Database (HMDB). The results showed the significant change in the level of some metabolites especially estrogenic steroids in different groups with different amounts of received Cd. The findings also indicated that steroid hormone biosynthesis, lysine biosynthesis and taurine and hypotaurine metabolism are the most affected pathways by CdTe-QDs especially in estrogenic steroids. The over-representation analysis indicated that endoplasmic reticulum, gonads, and hepatocytes are most affected. Since the pattern of metabolite alteration of CdTe-QDs with equivalent Cd2+ was similar to those of CdCl2, it was postulated that beside Cd2+ effects, the toxicity of CdTe-QDs is associated with other factors.


Assuntos
Compostos de Cádmio/toxicidade , Retículo Endoplasmático/efeitos dos fármacos , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Pontos Quânticos/toxicidade , Telúrio/toxicidade , Testículo/efeitos dos fármacos , Animais , Cádmio/química , Cádmio/toxicidade , Compostos de Cádmio/administração & dosagem , Compostos de Cádmio/química , Intoxicação por Cádmio/enzimologia , Intoxicação por Cádmio/metabolismo , Intoxicação por Cádmio/patologia , Relação Dose-Resposta a Droga , Retículo Endoplasmático/enzimologia , Retículo Endoplasmático/metabolismo , Injeções Intraperitoneais , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Masculino , Metabolômica/métodos , Camundongos , Especificidade de Órgãos , Tamanho da Partícula , Análise de Componente Principal , Pontos Quânticos/administração & dosagem , Distribuição Aleatória , Baço/efeitos dos fármacos , Baço/metabolismo , Baço/patologia , Propriedades de Superfície , Telúrio/administração & dosagem , Telúrio/química , Testículo/metabolismo , Testículo/patologia , Testes de Toxicidade Crônica
20.
Langmuir ; 32(49): 13084-13094, 2016 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-27951703

RESUMO

We present a method of modeling nanoparticle (NP) hydrophobicity using coarse-grained molecular dynamics (CG MD) simulations, and apply this to the interaction of lipids with nanoparticles. To model at a coarse-grained level the wettability or hydrophobicity of a given material, we choose the MARTINI coarse-grained force field, and determine through simulation the contact angles of MARTINI water droplets residing on flat regular surfaces composed of various MARTINI bead types (C1, C2, etc.). Each surface is composed of a single bead type in each of three crystallographic symmetries (FCC, BCC, and HCP). While this method lumps together several atoms (for example, one cerium and two oxygens of CeO2) into a single CG bead, we can still capture the overall hydrophobicity of the actual material by choosing the MARTINI bead type that gives the best fit of the contact angle to that of the actual material, as determined by either experimental or all-atom simulations. For different MARTINI bead types, the macroscopic contact angle is obtained by extrapolating the microscopic contact angles of droplets of eight different sizes (containing Nw = 3224-22978 water molecules) to infinite droplet size. For each droplet, the contact angle was computed from a best fit of a circular curve to the droplet interface extrapolated to the first layer of the surface. We then examine how small nanoparticles of differing wettability interact with MARTINI dipalmitoylphosphotidylcholine (DPPC) lipids and SP-C peptides (a component of lung surfactant). The DPPC shows a transition from tails coating the nanoparticle to a hemimicelle coating the water-wet NP, as the contact angle of a water droplet on the surface is lowered below ∼60°. The results are relevant to developing a taxonomy describing the potential nanotoxicity of nanoparticle interactions with components in the lung.


Assuntos
Lipídeos/química , Nanopartículas/química , Proteínas/química , Interações Hidrofóbicas e Hidrofílicas , Simulação de Dinâmica Molecular
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