During the recent years, more attentions have been focused on lipid base drug delivery system to overcome some limitations of conventional formulations. Among these delivery systems solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) are promising delivery systems due to the ease of manufacturing processes, scale up capability, biocompatibility, and also biodegradability of formulation constituents and many other advantages which could be related to specific route of administration or nature of the materials are to be loaded to these delivery systems. The aim of this article is to review the advantages and limitations of these delivery systems based on the route of administration and to emphasis the effectiveness of such formulations.

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Rivastigmine hydrogen tartrate (RHT), one of the potential cholinesterase inhibitors, has received great attention as a new drug candidate for the treatment of Alzheimer's disease. However, the bioavailability of RHT from the conventional pharmaceutical forms is low because of the presence of the blood brain barrier. The main aim of the present study was to prepare positively charged Eudragit RL 100 nanoparticles as a model scaffold for providing a sustained release profile for RHT. The formulations were evaluated in terms of particle size, zeta potential, surface morphology, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). Drug entrapment efficiency and in vitro release properties of lyophilized nanoparticles were also examined. The resulting formulations were found to be in the size range of 118 nm to 154 nm and zeta potential was positive (+22.5 to 30 mV). Nanoparticles showed the entrapment efficiency from 38.40 ± 8.94 to 62.00 ± 2.78%. An increase in the mean particle size and the entrapment efficiency was observed with an increase in the amount of polymer. The FTIR, XRD, and DSC results ruled out any chemical interaction between the drug and Eudragit RL100 polymer. RHT nanoparticles containing low ratio of polymer to drug (4:1) presented a faster drug release and on the contrary, nanoparticles containing high ratio of polymer to drug (10:1) were able to give a more sustained release of the drug. The study revealed that RHT nanoparticles were capable of releasing the drug in a prolonged period of time and increasing the drug bioavailability.

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Ethanol injection is one of the techniques frequently used to produce liposomes which favors both simplicity and safety. In this process, an ethanolic solution of lipids is rapidly injected into an aqueous medium through a needle, dispersing the phospholipids throughout the medium and promoting the vesicle formation. Being a critical parameter that determines the fate of liposome and its distribution, we studied different factors affecting the particle size of liposomes including different phospholipid (Phosal^® 53 MCT) and cholesterol concentrations and the use of different types of non-ionic surfactants at fixed Phosal^® 53 MCT concentration of 50 mg per formulation. Both Phosal^® 53 MCT and cholesterol concentration had direct effect on liposomes particle size. Non-ionic surfactants produced liposomes of smaller particle size when compared to conventional liposomes formed using Phosal^® 53 MCT 300 mg per formulation only, whereas this effect was diminished when higher Phosal^® 53 MCT to cholesterol ratios were used that obviously increased liposomes size. Smaller liposomes sizes were obtained upon using non-ionic surfactants of lower hydrophilic/hydrophobic balance (HLB) as both Tween 80 and Cremophor RH 40 produced liposomes of smaller particle size compared to Poloxamer 407. The smallest liposomes particle size was successfully obtained in the formulation comprising 300 mg Phosal^® MCT, 150 mg cholesterol and 50 mg Tween 80.

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The antioxidant and cytotoxic properties of four major parts of methanolic extracts of Tephrosia purpurea including leaves, root, stem and seed were investigated and compared. In vitro antioxidant activity of T. purpurea extracts was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), reducing power assay and antihemolytic assay. In vitro cytotoxic effect of T. purpurea extracts on SW620 colorectal cancer cell line was studied using 3-(4, 5-dimethylthiazolyl -2,5-diphenyl-tetrazolium bromide (MTT) assay. Folin-ciocalteu and aluminium chloride methods were used to determine the total phenolic and flavonoid contents respectively. Among the four extracts studied, leaves extract showed the highest antioxidant activity, DPPH: 186.3 ± 14.0 μg/mL, FRAP: 754.2 ± 50.9 μmol Fe(II)/mg and reducing power activity: 65.7 ± 4.2 μg/mg of quercetin equivalent (QE/mg) and there was no significant difference observed in antihemolytic activity. Leaves extract showed effective cytotoxicity on colorectal cancer cells (IC ₅₀ : 95.73 ± 9.6 μg/mL) and also had the higher total phenolic (90.5 ± 6.7 μg/mg of gallic acid equivalent (GAE/mg) and flavonoid content (21.8 ± 5.4 μg QE/mg). These results suggest higher antioxidant and cytotoxic activities of leaves extract in comparison with other extracts and these activities could be due to the presence of rich phenolic and flavonoid content.

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Increasing multiple drug resistant (MDR) strains of Acinetobacter baumannii has aggravated curiosity in development of alternative therapy. Bacteriophages are often considered as alternative agents for controlling A. baumannii infections. In the present study two lytic phages for MDR A. baumannii were isolated and their efficacy and host ranges were evaluated. The phages were isolated from hospital wastewater. Electron microscopy revealed that IsfAB78 might belong to Myoviridae and IsfAB39 to Podoviridae. Initial characterization of phages showed that they have narrow host range and failed to infect relative and non- relative bacteria. Both phages decreased the A. baumannii turbidity significantly, indicating that these isolated phages may be considered as candidates for phage therapy.

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The methylotrophic yeast Pichia pastoris is a well-established expression host, which is often used in the production of protein pharmaceuticals. This work aimed to evaluate the effect of various concentrations of ascorbic acid in mixed feeding strategy with sorbitol/methanol on productivity of recombinant human growth hormone (r-hGH). The relevant concentration of ascorbic acid (5, 10, or 20 mmol) and 50 g/L sorbitol were added in batch-wise mode to the medium at the beginning of induction phase. The rate of methanol addition was increased stepwise during the first 12 h of production and then kept constant. Total protein and r-hGH concentrations were analyzed and the results compared with sorbitol/methanol feeding using one-way analysis of variance. Moreover, an effective clarification process using activated carbon was developed to remove process contaminants like pigments and endotoxins. Finally, a three-step chromatographic process was applied to purify the product. According to the obtained results, addition of 10 mmol ascorbic acid to sorbitol/methanol co-feeding could significantly increase cell biomass (1.7 fold), total protein (1.14 fold), and r-hGH concentration (1.43 fold). One percent activated carbon could significantly decrease pigments and endotoxins without any significant changes in r-hGH assay. The result of the study concluded that ascorbic acid in combination with sorbitol could effectively enhance the productivity of r-hGH. This study also demonstrated that activated carbon clarification is a simple method for efficient removal of endotoxin and pigment in production of recombinant protein in the yeast expression system.

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Background and Purpose: Multiple sclerosis (MS) is an autoimmune disorder characterized by demyelination and axonal loss. Quantitative estimation of behavioral, locomotor, and histological changes following the use of alpha-tocopherol (AT) in the animal model of MS have not been reported. The present study was planned to evaluate whether AT can improve sensorimotor dysfunction and reduce demyelination in the cuprizone (CPZ)-induced rat model of MS. Experimental approach: Female Sprague-Dawley rats (8 weeks) were fed with cuprizone diet for 5 weeks followed by intraperitoneal injections of alpha-tocopherol (100 mg/Kg) or PBS for 2 weeks (groups E1 and E2, n = 8). Group C (n = 8) was fed with normal pellets followed by intraperitoneal doses of PBS. Open-field test and beam walking were carried out on every 10^th day. The mean area of demyelination in the corpus callosum was quantified in Luxol^® fast blue (LFB) stained histological sections of the forebrain. Qualitative grading for relative changes in the stains of myelinated fibers was also done. Findings/Results: During withdrawal of CPZ, AT treatment increased the average speed by 22% in group E1, compared to group E2 (P < 0.05). The mean time to walk the beam was reduced in group E1 by 2.6% compared to group E2 (P < 0.05). The rearing frequency was increased in group E1 during week 6-7 compared to that in the period of CPZ treatment. The mean area of demyelination in the corpus callosum showed a 12% reduction in group E1 compared to group E2 (P < 0.05). Conclusion and implications: Short-term AT therapy showed improvement in motor dysfunction and reduction of demyelination in the animal model of MS.

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Background and purpose: Vancomycin is a glycopeptide antibiotic which is the drug of choice against methicillin-resistant Staphylococcus aureus. It has a narrow therapeutic index, and thus therapeutic drug monitoring (TDM), and clinical pharmacokinetic assessment are necessary in order to prevent adverse drug reactions such as nephrotoxicity. In this study, we aimed to develop a simple and validated HPLC method for vancomycin assay in order to establish a TDM center for patients admitted to the ICU of Nemazee Hospital in southern Iran. Experimental approach: In this study, a brief review of different parameters and variables which could affect the sensitivity, selectivity of the validated HPLC method for vancomycin determination were considered. According to the previous studies a simple, fast, and the relatively low-cost method was established for vancomycin determination in plasma samples. Findings/Results: The developed HPLC assay indicated a calibration curve with R-square of > 0.999, acceptable selectivity, the accuracy of 90-105%, CV% of less than 15%, the limit of quantification of 1 μg/mL, and limit of detection of 300 ng/mL. Vancomycin trough level, the area under the curve, renal clearance, the volume of distribution,, and elimination constant were measured in patients using this validated method. Conclusion and implications: Validated method for assay of vancomycin plasma levels was used to quantify vancomycin levels of four patients who were admitted to the ICU of Nemazee Hospital. According to the results, two of these patients showed lower levels than recommended therapeutic purposes while one of them showed a toxic level. According to the results, the TDM assessment of vancomycin is strongly recommended for patients who are hospitalized in ICU.

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Bayesian estimation of pharmacokinetic parameters (PKP), as discussed in this review, provides a powerful approach towards the individualization of dosing regimens. The method was first described by Lewis Sheiner and colleagues and it is well suited in clinical environs where few blood fluid measures of drugs are available in the clinic. This makes it a valuable tool in the effective implementation of therapeutic drug monitoring. The principle behind the method is Bayes theorem, which incorporates elements of variability in a priori-known population estimates and variability in the pharmacokinetic parameters, and known errors intrinsic to the assay method used to estimate the blood fluid drug concentrations. This manuscript reviews the Bayesian method. The literature was scanned using Pubmed to provide background into the Bayesian method. An Add-in for Excel program was used to show the ability of the method to estimate PKP using sparse blood fluid concentration vs time data. Using a computer program, the method was able to find reasonable estimates of individual pharmacokinetic parameters, assessed by comparing the estimated data to the true PKP. Education of students in clinical pharmacokinetics is incomplete without some mention and instruction of the Bayesian forecasting method. For a complete understanding, a computer program is needed to demonstrate its utility.

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Background and purpose: Crocetin is a natural antioxidant that is found in the crocus flower and Gardenia jasminoides (fruit). Previous studies have reported its anticancer activity both in vivo and in vitro. In addition, crocetin suppresses the growth and migration of human colorectal cancer cells, however, its mechanism of action remains to be elucidated. Therefore, the present study investigated the molecular mechanism of crocetin effect on colorectal cancer cells (HCT-116) in vitro. Experimental approach: HCT-116 cells were treated with different concentrations (0, 200, 400, 600, and 800 μM) of crocetin for 24 h. The cell survival rate was measured by MTT assay. Cell migration capacity was evaluated using the wound healing assay. The expression levels of vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP-9) was monitored by RT-PCR. Phosphorylation of focal adhesion kinase (FAK) and p38 mitogen-activated protein kinase (MAPK) was determined using western blot. Findings/Results: The proliferation of HCT-116 was inhibited by crocetin at 800 μM (P < 0.001). Crocetin prevented migration of HCT-116 cells (P < 0.05) and suppressed VEGF and MMP-9 mRNA expression (P < 0.001) and increased phosphorylation of p38 (MAPK; P < 0.001). However, no significant change in the phosphorylation of FAK was observed. Conclusion and implication: These data suggested that crocetin-induced growth- and migration- suppressing effects on HCT-116 cells may partially depend on the regulation of the p38 (MAPK) signaling pathway.

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Reteplase is a non-glycosylated and recombinant form of tissue type plasminogen activator, which is produced in Escherichia coli. However, its overexpression usually leads to formation of inactive aggregates or inclusion bodies. In the present study, we report on the development of optimized processes for isolation, solubilization, and refolding of reteplase inclusion bodies to recover active protein. After protein overexpression in E. coli BL21 (DE3) inclusion bodies were isolated by cell disruption and repeated wash of pellet with buffer containing Triton X-100. To solubilize the inclusion bodies, different types, concentrations, pHs, and additives of denaturing agents were used. Rapid micro dilution method was applied for refolding of solubilized reteplase. Different chemical additives including sugars, alcohols, polymers, detergents, amino acids, kosmotropic, and chaotropic salts, reducing agents, and buffering agents were used in the refolding buffer. To evaluate the biological activity of refolded reteplase, an indirect chromogenic assay was performed. The best solubilizing agent for dissolving reteplase inclusion bodies was 6 M urea at pH 12. The optimized buffer for refolding of solubilized reteplase was found to be 1.15 M glucose, 9.16 mM imidazole, and 0.16 M sorbitol which resulted in high yield of biologically active protein. Our results indicate type, concentration, and pH of solvent and type, concentration, and combination of chemical additives can significantly influence the yield of inclusion bodies solubilization and refolding.

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Background and purpose: Cancer stem cells (CSCs), as the subpopulation of cancer cells, are associated with carcinogenesis, chemoresistance, and metastasis in malignancies. Also, CSCs are considered as the major reason for treatment failure in prostate cancer (PCa). Alantolactone (ALT), exerts anticancer activity in different types of cancers. In the present study, the relationship between ALT and CSCs in PCa metastasis and the molecular mechanisms involved in the progression of PCa were investigated. Experimental approach: In this study, to evaluate cell viability, MTT assay was performed. Then, PC3 cells were treated with nontoxic concentrations of ALT and after this step wound-healing assay, colony-formation assay and chemosensitization assay were applied to determine cell migration, the ability of colony formation, and chemoresistance, respectively. Also, real-time polymerase chain reaction and western blotting were used for the determination of genes and protein expression, respectively. Findings/Results: Our finding showed that ALT at nontoxic concentrations (0.01 and 0.1 μM) for 72 h suppressed the STAT3 phosphorylation and signaling pathway. Also, ALT was able to modulate the stemness of PCa cells through downregulation of expression of SOX2, Oct-4, Nanog, CD133, CD44, and upregulation of p53 expression. On the other hand, we further found that ALT in nontoxic concentrations sensitized PCa cells to cisplatin Conclusion and implications: ALT combated the stemness of cancer cells and metastasis by antagonizing of STAT3 signaling pathway. In addition, ALT exhibited anti-metastatic properties and may have potential as a new chemotherapy agent for the reduction of PCa metastasis.

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Background and purpose: Considering the undesirable consequences of prevalent cancer diseases, design and development of potent and selective anticancer chemotherapeutics is a major concern. Several studies have unraveled the potential of dihydropyrimidinone (DHPM) scaffold toward generating anticancer agents. Experimental approach: In the present work, a series of new dihydropyrimidinethiones (DHPMTs) along with a few acyclic enamino amides were synthesized and evaluated for their cytotoxic activity against human gastric (AGS), liver (Hep-G2), and breast (MCF-7) cancer cell lines. Findings/Results: Among the assessed compounds, one of the DHPMT derivatives (compound 5: 4-(3- fluorophenyl)-6-methyl-N-phenyl-2-thioxo-1,2,3,4-ttrahydropyrimidine-5-carboxamide) exhibited superior cytotoxicity in all of the target cell lines (AGS, IC₅₀ 9.9 μM; MCF-7, IC₅₀ 15.2 μM; and Hep-G2, IC₅₀ 40.5 μM). Cytotoxicity assessments showed that non-cyclic enamino amides exhibited weaker activities when compared to cyclic analogues (DHPMs). Conclusion and implications: DHPMTs were better cytotoxic agents than non-cyclic enamino amides. Structure activity relationship studies guided us toward the design of DHPMT derivatives with OH and NH groups particularly on meta position of 4-phenyl ring and hydrophobic bulky substituents on carboxamide side chain within the structure. Possible interaction with the hydrophobic site(s) of the cellular target was supposed. The results of this study emphasized the potential role of DHPMTs and their optimized derivatives as privileged medicinal scaffolds to inhibit the growth of gastric, breast, and liver cancer cells.

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Background and purpose: The most important adverse reaction of amphotericin B (AmB) is nephrotoxicity. The aim of this study was to assess the potential effectiveness of intravenous saline + sodium bicarbonate versus intravenous sodium chloride hydration in preventing or attenuating AmB nephrotoxicity. Experimental approach: A randomized, non-placebo-controlled, single-blinded clinical trial was conducted in two adult hematology-oncology wards of Namazi hospital. Eligible patients were randomly assigned into either the normal saline or normal saline + sodium bicarbonate groups by the ratio of 1:2. In the normal saline group, 1000 mL of sodium chloride 0.9% (154 meq sodium) was given intravenously as two equal 500 mL volumes before and during the infusion of AmB. Patients in the saline + sodium bicarbonate group received 500 mL sodium chloride 0.9% (72 meq sodium) before and 500 mL isotonic sodium bicarbonate (72 meq sodium) intravenously during AmB infusion. Findings/Results: The rate of AmB nephrotoxicity was comparable between normal saline and sodium bicarbonate groups (54.2% and 41.6%, respectively; P = 0.3). This difference did not reach the level of statistical significance after considering AmB dose and duration of the treatment. The frequency of hypokalemia and hypomagnesemia did not differ significantly between the two groups even after adjusting the results according to AmB dose and treatment duration. Conclusion and implications: The results of the current preliminary clinical trial suggested that the combination of sodium bicarbonate and normal saline compared to normal saline alone appears to have no superiority in preventing or attenuating different studied aspects of AmB nephrotoxicity in patients with hematological malignancies.

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Background and purpose: Venenum Bufonis is a Chinese traditional medicine produced from the glandular secretions of toads that contain biogenic amines, which have anti-inflammatory properties. The present study aimed to examine the effect of Bufo viridis secretions (BVS) on anxiety and depression-like behavior and hippocampal senile plaques volume in an animal model of Alzheimer's disease (AD). Experimental approach: Thirty-eight male Wistar rats were used. AD was induced by amyloid-beta (Aβ_1-42) (10 μg/2 μL, intracerebroventricular injection, icv) and then BVS at 20, 40, and 80 mg/kg were injected intraperitoneally (ip) in six equal intervals over 21 days. Anxiety and depression-like behavior were assessed using behavioral tests including open field test (OFT), elevated plus maze (EPM), and forced swimming test (FST) 21 days after the surgery. The volume of senile plaques was assessed based on the Cavalieri principle. Findings/Results: Results of the OFT showed that the central crossing number and the time in the AD group were significantly decreased compared to the sham group (P < 0.01 and P < 0.001, respectively). Also, the values of these two parameters significantly increased in the AD + BVS80 group than the AD group (P < 0.05 and P < 0.001, respectively). The time spent in the closed arm in the EPM dramatically increased in the AD group compared to the sham group (P < 0.05) and significantly decreased in the AD + BVS80 group compared to the AD group (P < 0.05). Results of the FST indicated that immobility time had a reduction in the AD + BVS20 (P < 0.01), AD + BVS40, and AD + BVS80 groups compared to the AD group (P < 0.001). The volume of senile plaques in the hippocampus showed a reduction in the treatment groups in comparison with the AD group (P < 0.001 for all). Conclusion and implications: Results revealed that BVS injection could improve symptoms of anxiety and depression and decrease senile plaques in the hippocampus in an animal model of AD.

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Low solubility and dissolution rate are the primary challenges in the drug development which substantially impact the oral absorption and bioavailability of drugs. Due to the poor water solubility, Albendazole (ABZ) is poorly absorbed from the gastrointestinal tract and shows low oral bioavailability (5%) which is a major disadvantage for the systemic use of ABZ. To improve the solubility and dissolution rate of ABZ, different classes of hydrophilic excipients such as sugars (lactose, sucrose, and glucose), polyols (mannitol and sorbitol), ionic surfactant (sodium lauryl sulfate) and non-ionic surfactant (Cremophor A25) were co-spray dried with ABZ. The crystallinity changes in the processed drug were characterized by differential scanning calorimetry and X-Ray diffraction methods were used to interpret the enhanced solubility and dissolution rate of the drug. Results showed that the solubility and dissolution rate of ABZ were increased 1.8-2.6 folds and 3-25 folds, respectively. Unexpectedly, SLS decreased the solubility index of drug powder even lower than the unprocessed drug which was attributed to drug-SLS ionic interaction as depicted from Fourier transform infrared spectroscopy. It was concluded that by applying the facile, one-step, industrially scalable technique and the use of small amounts of excipient (only 4% of the formulation), a great improvement (21 folds) in dissolution rate of ABZ was achieved. This finding may be used in the pharmaceutical industries for the formulation of therapeutically efficient dosage forms of class II and IV drugs classified in biopharmaceutical classification system.

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Background and purpose: Mercuric chloride (Merc) can cause kidney toxicity. Harmine (Harm), an herbal alkaloid has various pharmacological and medicinal effects mainly because of its antioxidant activity. In this study, therefore, Harm's protective mechanisms on Merc-induced nephrotoxicity in BALB/c male mice were investigated. Experimental approach: Forty-eight male mice were randomly divided into six groups (n = 8). Groups were received saline, Merc (0.5 mL/day of 0.5 ppm aqueous), Harm (5, 10, 15 mg/kg/day), Merc + Harm (5, 10, 15 mg/kg/day) for 14 consecutive days. Saline and Harm were administrated intraperitoneally and Merc dissolved in drinking water. Urea and creatinine serum levels, body weight, kidney weight, quantitative and qualitative histological alterations, apoptosis rate, total antioxidant capacity (TAC), superoxide dismutase (SOD), and nitric oxide (NO) levels were evaluated. Findings/Results: There was a significant reduction in total body and kidney weights, renal histological criteria, TAC, SOD levels in the Merc group compared to the control group (P < 0.05), whereas these parameters in the Merc + Harm groups, were significantly increased compared to the Merc group (P < 0.05). Urea and creatinine serum levels, levels of NO, and apoptosis were significantly higher in the Merc group than the control, while these parameters were decreased in the Merc + Harms groups in comparison with the Merc group (P < 0.05). Conclusion and implications: Harm protected Merc-induced renal damage in mice. This protection was observed in both histological and biochemical respects. The beneficial effect of Harm was related to its antioxidant properties that diminish NO production and apoptosis induction in the kidney.

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Background and purpose: Reactive oxygen species (ROSs) are continuously produced as byproducts of cell metabolism. Free radicals are an unstable form of ROSs with the tendency to react readily with biomolecules such as amino acids, lipids and DNA. These reactions lead to oxidative damages to the cell. Oxidative stress occurs when the concentration of the ROSs exceeds the capacity of antioxidative protection systems of the body. 5-Hydroxypyridin-4-one derivatives can chelate Fe²⁺ and Fe³⁺ due to their α-hydroxyketone moiety. Also, tautomerism in hydroxypyridinone ring leads to enough level of aromaticity resulting in a catechol-like behavior that provides them with good chelating and radical scavenging properties. Experimental approach: Different compounds were synthesized with 5-hydroxypyridine-4-one moiety as the core. The antioxidant properties of molecules were evaluated experimentally by DPPH scavenging method and theoretically using DFT/B3LYP with a 6-31++G (d,p) basis set. Electronic properties were investigated using frontier molecular orbital theory calculations. Furthermore, global descriptive parameters were obtained to find the chemical reactivity of molecules. The natural bond orbital analysis was performed to investigate charge distribution and hydrogen bonding. Findings/Results: Structures of the synthesized compounds were confirmed using IR, ¹H-NMR, and ¹³C-NMR spectral analyses. Among all the synthesized compounds, Va and Vb showed the best antioxidant effect experimentally and computationally. Conclusion and implications: Results of this study were valuable in terms of synthesis, in silico, and in vitro antioxidant evaluations and can be useful for future investigations about the design of novel 5-hydroxypyridin- 4-one derivatives possessing iron-chelating and radical scavenging abilities.

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Overexpression of recombinant proteins in Escherichia coli results in inclusion body formation, and consequently decreased production yield and increased production cost. Co-expression of chaperon systems accompanied by recombinant protein is a general method to increase the production yield. However, it has not been successful enough due to imposed intense stress to the host cells. The aim of this study was to balance the rate of protein production and the imposed cellular stresses using a two-step expression system. For this purpose, in the first step, green fluorescent protein (GFP) was expressed as a recombinant protein model under control of the T7-TetO artificial promoter-operator, accompanied by Dnak/J/GrpE chaperon system. Then, in the next step, TetR repressor was activated automatically under the control of the stress promoter ibpAB and suppressed the GFP production after accumulation of inclusion bodies. Thus in this step incorrect folded proteins and inclusion bodies are refolded causing increased yield and solubility of the recombinant protein and restarting GFP expression again. Total GFP, soluble and insoluble GFP fractions, were measured by Synergy H1 multiple reader. Results showed that expression yield and soluble/insoluble ratio of GFP have been increased 5 and 2.5 times using this system in comparison with the single step process, respectively. The efficiency of this system in increasing solubility and production yield of recombinant proteins was confirmed. The two-step system must be evaluated for expression of various proteins to further confirm its applicability in the field of recombinant protein production.

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This study describes the formation of multicomponent crystal (MCC) of desloratadine (DES). The objective of this study was to discover the new pharmaceutical MCC of DES using several coformers. The MCC synthesis was performed between DES and 26 coformers using an equimolar ratio with a solvent evaporation technique. The selection of the appropriate solvent was carried out using 12 solvents. The preview of the MCC of DES was performed using polarized light microscopy (PLM). The formation of MCC was confirmed using powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The accelerated stability of MCC at 40 °C and relative humidity of 75% was investigated using PXRD and FTIR. Depending on the prior evaluation, DES and benzoic acid (BA) formed the MCC. PLM and SEM results showed that crystal habit of combination between DES and BA differed from the constituent components. Moreover, the diffractogram pattern of DES-BA was distinct from the constituent components. The DSC thermogram showed a new peak which was distinct from both constituent components. The FTIR study proved a new spectrum. All characterizations indicated that a new solid crystal was formed, ensuring the MCC formation. In addition, DES-BA MCC had both chemical and physical stabilities for a period of 4 months.

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For high-throughput production of recombinant protein in Escherichia coli (E. coli ), besides important parameters such as efficient vector with strong promoter and compatible host, other important issues including codon usage, rare codons, and GC content specially at N-terminal region should be considered. In the current study, the effect of decreasing the percentage of GC nucleotides and optimizing codon usage at N-terminal region of human growth hormone (hGH) cDNA on the level of its expression in E. coli were investigated. Mutation in cDNA of hGH was performed through site-directed mutagenesis using PCR. Then, the mutant genes were amplified and cloned into the expression vector, pET-28a. The new constructs were transformed into the BL21(DE3) strain of E. coli and chemically induced for hGH expression. At the final stage, expressed proteins were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), scanning gel densitometry, and western blot. SDS-PAGE scanning gel densitometry assay and western blot analysis revealed higher expression level of hGH by using the two new expressions constructs (mutant genes vectors with decreasing GC content and optimized-codon usage at N-terminal of cDNA) in comparison with wild gene expression vector. Obtained results demonstrated that decreasing the GC nucleotide content and optimization of codon usage at N-terminal of the hGH cDNA could significantly enhance the expression of the target protein in E. coli. Our results highlight the important role of both 5´ region of the heterologous genes in terms of codon usage and also GC content on non-host protein expression in E. coli.

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Deferoxamine mesylate (DFO) is administered as a slow subcutaneous or intravenous infusion due to its poor oral bioavailability and lack of dose proportionality. The aim of the present study was to prepare and optimize polymeric micelles containing DFO, as an oral drug delivery system for increasing permeability and oral bioavailability. Based on a full factorial design with three variables in two levels, eight polymeric micelle formulations were made using film hydration method. Two polymers including 0.1% of carbomer 934 and Poloxamer^® P 407 and two blends of surfactant + co-surfactant including 1 and 2 fold of critical micelle concentration of Labrafil^® + Labrasol^® and Tween 80 + Span 20 were used to prepare polymeric micelles. The effect of variables on particle size (PS), entrapment efficiency (EE), drug release, thermal behavior, in vitro iron bonding and ex vivo rat intestinal permeability were evaluated. The PS of polymeric micelles was less than 83 nm that showed 80% EE with continuous drug release pattern. The change in type of polymer from carbomer to Ploxamer^® significantly increased drug release. All polymeric micelles increased the iron-bonding ability of DFO compared to control. This could be due to surfactants that can play an important role in this ability. Polymeric micelles increased drug permeability through intestine more than 2.5 folds compared to control mainly affected by polymer type. Optimized polymeric micelle consists of Tween 80 and Span 20 with 1.35 folds of critical micelle concentration and Poloxamer^® demonstrated 97.32% iron bonding and a 3-fold increase in permeation through the rat intestine compared with control.

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In recent years, the use of the antioxidant in reducing heavy metal toxicities has increased worldwide. Curcumin has been reported to have a strong antioxidant activity. In this study, we investigated the protective effects of curcumin on lead acetate-induced testicular damage in rats. The sample used 40 male rats divided into 5 groups: negative control (rats were given daily with corn oil); positive control (rats were given daily with lead acetate 50 mg/kg BW orally once in a day for 35 days); and the treatment group (rats were given the curcumin 100 mg, 200 mg, and 400 mg/kg BW orally once in a day for 40 days, and on the 5^th day, were given lead acetate 50 mg/kg BW one h after the curcumin administration). After 40 days, levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in testicular tissue, and sperm count, motility and viability in the epididymis were measured in rats. Testis samples were also collected for histopathological studies. Results showed that lead acetate administration significantly decreased the SOD, GPx, and increased MDA levels. Lead acetate also decreased the sperm count, motility, viability, and altered histopathological testis (testicular damage, necrosis of seminiferous tubules and loss of spermatid) compared to the negative control. However, administration of curcumin significantly improved the histopathological in testis, increased the sperm count, motility, viability, and also significantly increased the SOD, GPx, and decreased MDA in testis of lead acetate-treated rats. From the results of this study we concluded that the curcumin could be a potent natural product provide a promising protective effect against lead acetate induced testicular toxicity in rats.

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In the current study, floating dosage form containing acyclovir was developed to increase its oral bioavailability. Effervescent floating tablets containing 200 mg acyclovir were prepared by direct compression method with three different rate controlling polymers including Hydroxypropyl methylcellulose K4M, Carbapol 934, and Polyvinylpyrrolidone. Optimized formulation showed good floating properties and in vitro drug release characteristics with mean dissolution time and dissolution efficacy of about 4.76 h and 54.33%, respectively. X-ray radiography exhibited that the tablet would reside in the stomach for about 5 ± 0.7 h. After oral administration of floating tablet containing 200 mg acyclovir, the C_max, T_max, and AUC_0–∞ of optimized gastroretentive formulation were found to be 551 ± 141 ng/mL, 2.75 ± 0.25 h and 3761 ± 909.6 ng/mL/h, respectively.

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Inhalable dry powders containing poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs) were developed for the delivery of tadalafil (TAD) for treatment of life-treating pulmonary arterial hypertension. Taguchi design was employed to evaluate the effects of different formulation variables on the physicochemical characteristics of PLGA-NPs prepared using emulsion solvent evaporation method. Inhalable PLGA-NPs of TAD were successfully prepared by co-spray drying the PLGA-NPs with inert carriers. Physicochemical characteristics and in vitro deposition of the aerosolized drug were also evaluated. The optimized formulation was prepared using 7.5 mg of PLGA, 2.5 mg of TAD, sonication time of 6 min and 2% polyvinyl alcohol (PVA) as the stabilizer. The optimized aqueous/oil phase ratio for PLGA-NPs preparation was 10:1. Polymer/drug ratio was the most effective parameter on the release efficiency. Encapsulation efficiency, zeta potential and particle size of PLGA-NPs were more affected by aqueous/organic phase ratio. The spray dried powders containing PLGA-NPs had a mass median aerodynamic diameter (MMAD) in the range of 1.4–2.8 μm that was suitable for TAD delivery to the deep region of lung. The presence of L- leucine in mannitol containing formulations decreased the interparticulate forces between particles and increased significantly the process yield and fine particle fraction (FPF). The results indicated that prepared dry powders containing TAD-loaded PLGA-NPs were suitable for inhalation and has the potential for the treatment of pulmonary arterial hypertension.

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