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Mona Noori Koopaei1, Rassoul Dinarvand1,2, Mohsen Amini3, Hojatollah Rabbani4, Shaghayegh Emami4, Seyed Nasser Ostad5, Fatemeh Atyabi1,21Novel Drug Delivery Laboratory, Faculty of Pharmacy, 2Nanotechnology Research Center, 3Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 4Monoclonal Antibody Research Center, Avesina Research Institute, ACECR, Tehran, Iran; 5Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Science, Tehran, IranBackground: The objective of this study was to develop pegylated poly lactide-co-glycolide acid (PLGA) immunonanocarriers for targeting delivery of docetaxel to human breast cancer cells.Methods: The polyethylene glycol (PEG) groups on the surface of the PLGA nanoparticles were functionalized using maleimide groups. Trastuzumab, a monoclonal antibody against human epidermal growth factor receptor 2 (HER2) antigens of cancer cells, used as the targeting moiety, was attached to the maleimide groups on the surface of pegylated PLGA nanoparticles. Nanoparticles prepared by a nanoprecipitation method were characterized for their size, size distribution, surface charge, surface morphology, drug-loading, and in vitro drug release profile.Results: The average size of the trastuzumab-decorated nanoparticles was 254 ± 16.4 nm and their zeta potential was -11.5 ± 1.4 mV. The average size of the nontargeted PLGA nanoparticles was 183 ± 22 nm and their zeta potential was -2.6 ± 0.34 mV. The cellular uptake of nanoparticles was studied using both HER2-positive (SKBR3 and BT-474) and HER2-negative (Calu-6) cell lines.Conclusion: The cytotoxicity of the immunonanocarriers against HER2-positive cell lines was significantly higher than that of nontargeted PLGA nanoparticles and free docetaxel.Keywords: nanoparticles, drug targeting, immunonanocarriers, trastuzumab, docetaxel, PLGA, HER2 receptor

Abstract Background Anaemia is a common health problem in the developing world. This condition is characterized by a reduction in erythrocyte density, primarily from malnutrition and/or infectious diseases such as malaria. As red blood cells are the primary source of protein for haematophagous mosquitoes, any reduction could impede the ability of mosquito vectors to transmit malaria by influencing their fitness or that of the parasites they transmit. The aim of this study was to determine the impact of differences in the density of red blood cells in human blood on malaria vector (Anopheles gambiae sensu stricto) fitness. The hypotheses tested are that mosquito vector energetic reserves and fitness are negatively influenced by reductions in the red cell density of host human blood meals commensurate with those expected from severe anaemia. Methods Mosquitoes (An. gambiae s.s.) were offered blood meals of different packed cell volume (PCV) of human blood consistent with those arising from severe anaemia (15%) and normal PCV (50%). Associations between mosquito energetic reserves (lipid, glucose and glycogen) and fitness measures (reproduction and survival) and blood meal PCV were investigated. Results The amount of protein that malaria vectors acquired from blood feeding (indexed by haematin excretion) was significantly reduced at low blood PCV. However, mosquitoes feeding on blood of low PCV had the same oviposition rates as those feeding on blood of normal PCV, and showed an increase in egg production of around 15%. The long-term survival of An. gambiae s.s was reduced after feeding on low PCV blood, but PCV had no significant impact on the proportion of mosquitoes surviving through the minimal period required to develop and transmit malaria parasites (estimated as 14 days post-blood feeding). The impact of blood PCV on the energetic reserves of mosquitoes was relatively minor. Conclusions These results suggest that feeding on human hosts whose PCV has been depleted due to severe anaemia does not significantly reduce the fitness or transmission potential of malaria vectors, and indicates that mosquitoes may be able exploit resources for reproduction more efficiently from blood of low rather than normal PCV.

Phosphate is an essential macronutrient required for cell growth and division. Pho84 is the major high-affinity cell-surface phosphate importer of Saccharomyces cerevisiae and a crucial element in the phosphate homeostatic system of this model yeast. We found that loss of Candida albicans Pho84 attenuated virulence in Drosophila and murine oropharyngeal and disseminated models of invasive infection, and conferred hypersensitivity to neutrophil killing. Susceptibility of cells lacking Pho84 to neutrophil attack depended on reactive oxygen species (ROS): pho84-/- cells were no more susceptible than wild type C. albicans to neutrophils from a patient with chronic granulomatous disease, or to those whose oxidative burst was pharmacologically inhibited or neutralized. pho84-/- mutants hyperactivated oxidative stress signalling. They accumulated intracellular ROS in the absence of extrinsic oxidative stress, in high as well as low ambient phosphate conditions. ROS accumulation correlated with diminished levels of the unique superoxide dismutase Sod3 in pho84-/- cells, while SOD3 overexpression from a conditional promoter substantially restored these cells' oxidative stress resistance in vitro. Repression of SOD3 expression sharply increased their oxidative stress hypersensitivity. Neither of these oxidative stress management effects of manipulating SOD3 transcription was observed in PHO84 wild type cells. Sod3 levels were not the only factor driving oxidative stress effects on pho84-/- cells, though, because overexpressing SOD3 did not ameliorate these cells' hypersensitivity to neutrophil killing ex vivo, indicating Pho84 has further roles in oxidative stress resistance and virulence. Measurement of cellular metal concentrations demonstrated that diminished Sod3 expression was not due to decreased import of its metal cofactor manganese, as predicted from the function of S. cerevisiae Pho84 as a low-affinity manganese transporter. Instead of a role of Pho84 in metal transport, we found its role in TORC1 activation to impact oxidative stress management: overexpression of the TORC1-activating GTPase Gtr1 relieved the Sod3 deficit and ROS excess in pho84-/- null mutant cells, though it did not suppress their hypersensitivity to neutrophil killing or hyphal growth defect. Pharmacologic inhibition of Pho84 by small molecules including the FDA-approved drug foscarnet also induced ROS accumulation. Inhibiting Pho84 could hence support host defenses by sensitizing C. albicans to oxidative stress.

Due to the mineralogical characteristics of marls and the concentration of impermeable clay minerals in the bodies of these types of rocks and sediments, the establishment and growth of vegetation in marl lands is usually hard. This research aims to systematically investigate relatively densely grown plant species and determine their habitat needs as well as their protective role in the soils resulting from the erosion of the Marni formation with a bed of the Gurpi marly belonging to the Cretaceous period with a thickness of more than 100 meters in two regions Westgan and Dorahan in Borujen city of Chaharmahal and Bakhtiari province were implemented. For this purpose, 65 marl soil samples were taken, and physical and chemical tests were performed on 31 samples. Botanical surveys were performed using repeated field visits within 180 plots, and plant samples were identified after moving to the plant museum (Herbarium) of the agricultural and natural resources research and education center. In general, out of more than 400 existing plant species growing in the region and on different formations, a collection of rangelands species Astragalus brachycalyx-Daphne mucronata-Cirsium bracteosum with a density of more than 50% can be found in the lands resulting from the erosion of neutral marl formations (PH = 7-8) with a moderate amount of lime and minimal presence of Na+ and Cl- to be established. On the other hand, a complex colony of rangelands species with a combination of Astragalus susianus-Daphne mucronata-Amygdalus elaeagnifolia can be established in alkaline marl soils (PH ≥ 8) and with the predominance of the calcareous component in rock and sediment in the presence of very high Cl- values and as a biological solution. Water erosion control in soils affected by the erosion of alkaline marl should be provided. [ABSTRACT FROM AUTHOR]