Search

Objective(s): Magnetic iron oxide nanoparticles are remarkably potent drug nanocarriers due to their intrinsic capacity for elevated drug loading, biocompatibility, stability. This study focused on the development of iron oxide (Fe3O4) nanoparticles by the green synthesis method and PEGylated method, utilizing Eriobotrya japonica leaf extract. Methods: The physicochemical parameters were determined using Dynamic Light Scattering (DLS), Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FTIR), X-ray Diffraction (XRD), and cytotoxicity test methods. Eventually, polyethylene glycol (PEG) was utilized to coat the surface and ensure the stability of the final nanomedicine formulation. Results: The DLS evaluation of iron oxide nanoparticles revealed an average hydrodynamic size of 155 nm. FESEM showed that the network of spherical with small building blocks was formed by the green synthesis method and coated with polyethylene glycol. The X-ray Energy Dispersive Spectroscopy analysis reveals a significant percentage of carbon (C), oxygen (O), as well as some sulfur (S), chlorine (Cl), and iron (Fe). The FTIR analysis verified the existence of acidic O-H and alkene, C-H, C-N, and C-O functional groups compared to the bare nanoparticle. The cytotoxicity test investigation indicated that the inhibitory concentrations (IC50) toxicity of iron oxide nanoparticles, obtained by the green synthesis method on the MCF-7 cell line, was 1763 µg/ml. Conclusions: These nanoparticles exhibited a favorable dispersion index, efficient incorporation of plant extract fractions into the nanoparticle network, and minimal toxicity in the final product. Consequently, these nanoparticles are wellsuited for biomedical research and drug delivery applications. [ABSTRACT FROM AUTHOR]

Background: Resistance to artemisinin has threatened major achievements in malaria control, more investigations is needed about resistant strains and related genes. We aimed to induce resistance to artesunate in the Plasmodium falciparum 3D7 strain using intermittent exposure method and comparing P.fk13 gene sequence between susceptible and resistance strains. Methods: P. falciparum 3D7 strain was cultured according to Trager & Jensen method with some modifications. Serial concentrations between 10-2 mol/l, to 10-7mol/l were prepared, then P. falciparum 3D7 was exposed to each of the dilution to determine IC50 and lethal dose. Sensitivity reduction process was started from the concentration of 10-7mol/l and ended at 10-2mol/l. Exposed parasites were collected after at least 27 days after cultivation in each drug concentration. DNA extraction, PCR and sequencing process were performed to investigate any possible mutations in the P.fk13 gene sequence. Results: Effectiveness of 10-2mol/l concentration of artemisinin was found as a lethal dose. IC50 value was equal to 5*10-4 mol/l. The resistant strain was provided in the lab, sequenced and registered in the gene bank as P.f Art -2, (accession number MH796123. 1). Alignment of this registered sample showed no mutation in P.f kelch13 gene in comparison with standard strain submitted in the GenBank. Conclusion: Resistance to artesunate in malaria parasite may occur but with no mutation in the P.f kelch13 gene. Therefore, whole genome sequencing should be applied to determine mutations in resistant strains. [ABSTRACT FROM AUTHOR]

Background: The use of antimalarial drugs with number of compounds in combination form may potentiate each other's activity. Methods: This study was conducted in the School of Public Health, Tehran University of Medical Sciences, Tehran, Iran in 2018. It was based on two methods including in vivo and in vitro tests with aim of considering interaction between chitosan and chloroquine against Plasmodium berghei and P. falciparum parasites using different ratios of the agents with ED50s and IC50s baselines. Results: Administrating 10 and 20 mg/kg (mouse body weight) of chitosan alone to the P. berghei --infected mice up to 4 successive days resulted in 37% and 45% inhibition of P. berghei respectively, while employing the compound with chloroquine in combination form with ratios of 90/10 and 70/30 (chloroquine/chitosan) had a considerable potentiation including 71.58% and 83.85% inhibition effectiveness against P. berghei. Moreover, 20 mg/L (CCM) concentration of chitosan alone could eliminate 69.55% of P. falciparum in culture medium while in combination with chloroquine in ratios of 90/10 (chloroquine/chitosan) had considerable potentiation including 79.14% inhibition effectiveness. Mean survival time of those mice received combination therapy in ratios of 90/10 and 70/30 (chloroquine/chitosan) was longer than those took up mono therapy of either chloroquine or chitosan based on their ED50s doses. Conclusion: Interaction between chloroquine and chitosan showed considerable potentiation in combination form against either P. berghei or P. falciparum using in vivo and in vitro tests respectively. Meanwhile, interaction between the above mentioned agents resulted in a notable survival time for those P. berghei-infected mice treated with the combination. [ABSTRACT FROM AUTHOR]

Background: To overcome human malaria problem several solutions have been employed including extensive studies in the field of Plasmodia relevant antigens. The aim of this study was to determine allelic variation in the MSP1 gene of Plasmodium falciparum among some falciparum malaria-infected patients in Southeastern Iran. Methods: Twenty P. falciparum positive cases were enrolled from Sistan and Baluchistan Province, southeastern Iran in 2013-15. From each case, 1.5ml of peripheral blood was collected into EDTA contained tubes. Thick and thin blood smears were stained with standard Giemsa stain and were checked with conventional microscopical method. DNA was extracted from blood samples and amplification of block 2 MSP1 was performed using specific primers. Gel electrophoresis was done and results showed some amplification fragments corresponding to block 2 regions of Pf MSP1 gene. Finally, four samples from different allelic types were sent for sequencing process. Results: Fragments were different in size, so classified into six allelic types as kinds of 1-6 based on happening frequencies. Digestion of PCR products revealed two sub allelic types (A and B) within allelic types 2 and 3, but not in allelic types 1, 4, 5 and 6. Twenty percent of samples were sent for sequencing. Sequence alignment showed 78.95% to 91.83% identity between samples. Conclusion: Identity between samples and phylogenetic tree revealed that there is an extensive diversity range among isolates. Fifty percent of the isolates were under the risk of complicated malaria. Two of these patients (10%) needed special care and recovery was obtained after getting hospital services. [ABSTRACT FROM AUTHOR]