Ultra-sensitive electrochemical sensing of acetaminophen and codeine in biological fluids using CuO/CuFe2O4 nanoparticles as a novel electrocatalyst

Copper ferrite–copper oxide (CuO-CuFe₂O₄) nanoparticles as a semiconductor composite with p–n junction were synthesized by co-precipitation reaction. Then, a novel CuO-CuFe₂O₄ carbon paste modified electrode was fabricated which displays an effectual electrocatalytic response to the oxidation of acetaminophen (AC) and codeine (CO). A linear range of 0.01–1.5 μmol L⁻¹ and 0.06–10.0 μmol L⁻¹ with the detection limits of 0.007 μmol L⁻¹ and 0.01 μmol L⁻¹ were achieved for AC and CO, respectively. The practical usage of the proposed sensor revealed reasonable results for quantification of AC and CO in biological fluids.     

Huperzine A ameliorates cognitive dysfunction and neuroinflammation in kainic acid‐induced epileptic rats by antioxidant activity and NLRP3/caspase‐1 pathway inhibition

Temporal lobe epilepsy (TLE) is one of the most prevalent types of epilepsy in human. Huperzine A (Hup‐A) has been reported to possess antioxidative and anti‐inflammatory properties; however, its role in TLE induced by kainic acid has not been determined. The current study investigated the protective effects of Hup‐A (0.1 mg/kg) in kainic acid‐induced model of TLE in the rat. In the current study, it was found that Hup‐A significantly prevented the seizure intensity and learning and memory deterioration which was assessed by Morris water maze (MWM) and novel object recognition task (NOR). Additionally, Hup‐A inhibited oxidative stress, inflammation, and acetylcholinesterase activity (AChE). In addition, catalase and superoxide dismutase (SOD) activities increased after Hup‐A treatment, while malondialdehyde (MDA) and nitrite levels significantly reduced. Regarding inflammation, this drug decreased kainic acid‐induced NLRP3 expression in microglial cells and caspase‐1 activity in hippocampal tissue, possibly through diminishing oxidative stress. Taken together, our data showed that Hup‐A could be a potential protective substance to ameliorate seizure severity and some memory deficits related to epilepsy via attenuating neuroinflammation and protection of neurons.     

Design,synthesis, molecular docking study,and antibacterial evaluation of some new fluoroquinolone analogues bearing a quinazolinone moiety

BackgroundIncreasing bacterial resistance to quinolones is concerning. Hence, the development of novel quinolones by chemical modifications to overcome quinolone resistance is an attractive perspective in this context.ObjectiveIn this study, it is aimed to design and synthesize a novel series of functionalized fluoroquinolones using ciprofloxacin and sarafloxacin cores by hybridization of quinazolinone derivatives. This objective was tested by a comprehensive set of in vitro antibacterial assays in addition to SAR (structure–activity relationship) characterisation studies.MethodsA nucleophilic reaction of ciprofloxacin and sarafloxacin with 2-(chloromethyl)quinazolin-4(3H)-one in the presence of NaHCO₃ in dimethylformamide (DMF) was performed to obtain the desired compounds 5a-j. Novel compounds were characterised by ¹H, ¹³C- NMR and IR spectroscopy, MS and elemental analysis. In silico pharmacokinetics prediction assays and molecular docking studies were performed to explore the binding characteristics and interactions. Antibacterial activities of the novel compounds were evaluated by Broth microdilution, well diffusion and disc diffusion assays against three gram-positive (Methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus and Enterococcus faecalis) and three gram-negative bacteria (Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli).ResultsThe compounds exhibited moderate to good activities against gram-positive bacteria and weak to moderate activities against gram-negative bacteria. Amongst all ciprofloxacin-derivatives, compound 5d was the most potent agent with high antibacterial activity against gram-positive bacteria, including MRSA and S. aureus ((minimum inhibitory concentration (MIC) = 16 nM for both), that is 60 times more potent than ciprofloxacin as parent drug. Compound 5i from sarafloxacin-derivatives was the most potent compound against MRSA and S. aureus (MIC = 0.125 μM). Well diffusion and disk diffusion assay results demonstrated confirmatory outcomes for the quantitative broth microdilution assay. Molecular docking study results were in accordance with the results of antibacterial activity assays.ConclusionThe results of the current study demonstrated that the novel ciprofloxacin and sarafloxacin derivatives synthesized here have promising antibacterial activities. Particularly, compounds 5d and 5i have potential for wider antibacterial applications following further analysis.Graphical abstractElectronic supplementary materialThe online version of this article (10.1007/s40199-020-00373-6) contains supplementary material, which is available to authorized users.     

Inadvertent rubella vaccination of pregnant women: evaluation of possible transplacental infection with rubella vaccine

During mass campaign for measles/rubella vaccination on December 2003 in Iran, many pregnant women have vaccinated mistakenly. These women were grouped to susceptible and immune against rubella before vaccination by the status of IgG avidity response to rubella vaccine, then susceptible women were followed up to delivery time and their neonates were followed up to one year. In five neonates that were born from susceptible women, rubella-specific IgM has detected in cord blood sera, but they have not shown signs compatible to congenital rubella syndrome.     

The impact of polymer coatings on magnetite nanoparticles performance as MRI contrast agents: a comparative study

Background

Superparamagnetic iron oxide nanoparticles (SPIONs) are the most commonly used negative MRI contrast agent which affect the transverse (T₂) relaxation time. The aim of the present study was to investigate the impact of various polymeric coatings on the performance of magnetite nanoparticles as MRI contrast agents.

Methods

Ferrofluids based on magnetite (Fe₃O₄) nanoparticles (SPIONs) were synthesized via chemical co-precipitation method and coated with different biocompatible polymer coatings including mPEG-PCL, chitosan and dextran.

Results

The bonding status of different polymers on the surface of the magnetite nanoparticles was confirmed by the Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The vibrating sample magnetometer (VSM) analysis confirmed the superparamagnetic behavior of all synthesized nanoparticles. The field–emission scanning electron microscopy (FE-SEM) indicated the formation of quasi-spherical nanostructures with the final average particle size of 12–55 nm depending on the type of polymer coating, and X-ray diffraction (XRD) determined inverse spinel structure of magnetite nanoparticles. The ferrofluids demonstrated sufficient colloidal stability in deionized water with the zeta potentials of −24.2, −16.9, +31.6 and −21 mV for the naked SPIONs, and for dextran, chitosan and mPEG-PCL coated SPIONs, respectively. Finally, the magnetic relaxivities of water based ferrofluids were measured on a 1.5T clinical MRI instrument. The r₂/r₁ value was calculated to be 17.21, 19.42 and 20.71 for the dextran, chitosan and mPEG-PCL coated SPIONs, respectively.

Conclusions

The findings demonstrated that the value of r₂/r₁ ratio of mPEG-PCL modified SPIONs is higher than that of some commercial contrast agents. Therefore, it can be considered as a promising candidate for T₂ MRI contrast agent.     

Toxicological Effects of Glycyrrhiza glabra (Licorice): A Review

Licorice (Glycyrrhiza glabra) has been considered as an herbal drug since ancient time. Nowadays, it is a well‐known spice that possesses worth pharmacological effects. However, some relevant articles have revealed negative impacts of licorice in health. By considering the great wishes in using herbal medicine, it is important to show adverse effects of herbal medicine in health. At present, there are misunderstandings toward the safety of herbal medicines. Herein, we gathered scientific research projects on the toxicity effects of licorice and glycyrrhizin to highlight their safety. In this regards, we categorized our findings about the toxicity effects of licorice and glycyrrhizin in acute, sub‐acute, sub‐chronic, and chronic states. Besides, we discussed on the cytotoxicity, genotoxicity, mutagenicity, and carcinogenicity of licorice and glycyrrhizin as well as their developmental toxicity. This review disclosed that G. glabra and glycyrrhizin salts are moderately toxic. They need to be used with caution during pregnancy. G. glabra and glycyrrhizin possess selective cytotoxic effects on cancerous cells. The most important side effects of licorice and glycyrrhizin are hypertension and hypokalemic‐induced secondary disorders. Licorice side effects are increased by hypokalemia, prolonged gastrointestinal transient time, decreased type 2 11‐beta‐hydroxysteroid dehydrogenase activities, hypertension, anorexia nervosa, old age, and female sex. Copyright © 2017 John Wiley & Sons, Ltd.     

Preliminary Survey of Aflatoxins and Ochratoxin A in Dried Fruits from Iran

Forty five dried fruits, 30 dried apricots and 15 prunes were tested for aflatoxins and ochratoxin A contamination utilizing immunoaffinity column clean up and high performance liquid chromatography (HPLC) with fluorescence detection. 30% and 3.33% of examined apricot samples and 13.33% and 20% of examined prunes samples contained aflatoxin B₁ and ochratoxin A more than 0.2 ng g⁻¹. The average recoveries were found to be 91.1% and 98.5% for aflatoxin B₁ and ochratoxin A, respectively, while the detection limit was 0.2 ng g⁻¹ for both mycotoxins.     

Validity and reliability of a nutrition screening tool in hospitalized patients

Objective

The British nutrition screening tool is a questionnaire designed to assess the nutrition status of hospitalized patients by nurses. The aim of this study was to evaluate the validity and reliability of this questionnaire in patients on admission to the hospital in Tehran.

Methods

For 6 mo, 446 patients aged over 18 y admitted to different wards of a general hospital were studied within the first 24 h of admission. A nutritionist undertook nutritional assessment in all patients to determine their nutritional status as an objective standard. Then a nurse completed the screening tool for patients. Results obtained using the screening tool were compared with those of the nutritional assessment to calculate the sensitivity, specificity, and predictive values. The interrater reliability of the tool was assessed by two nurses who completed the screening tool separately during the first 24 h following admission of each patient. It was also completed by a nurse within 2-d period of admission to test the intrarater reliability.

Results

Study participants included 229 women and 217 men with mean age of 49.5 ± 16.0 y. Sensitivity and specificity of the questionnaire were 86.7% (95% CI: 83.9-90.3%) and 61.7% (95% CI: 57.5-66.5%), respectively. Positive and negative predictive values were 79.1% (95% CI: 68.9-77.1%) and 73.1% (95% CI: 75.1-82.9), respectively. The sensitivity of the tool was over 80% for both genders, for all body mass index grades, and for data obtained from gastroenterology, transplant, oncology, and hematology wards. The interrater reliability of screening tool was interpreted as substantial, being k = 0.68 and k = 0.74 on both the first and second days, respectively. The intrarater reliability of the screening tool was also interpreted as substantial, being k = 0.77.

Conclusion

The nutrition screening tool is a simple, valid, and reliable tool that can be used by nurses to facilitate identification of patients requiring nutritional interventions.     

Tensile-Tearing Fracture Analysis of U-Notched Spruce Samples

Spruce wood (Picea Mariana) is a highly orthotropic material whose fracture behavior in the presence of U-shaped notches and under combined tensile-tearing loading (so-called mixed-mode I/III loading) is analyzed in this work. Thus, several tests are carried out on U-notched samples with different notch tip radii (1 mm, 2 mm, and 4 mm) under various combinations of loading modes I and III (pure mode I, pure mode III, and three mixed-mode I/III loadings), from which both the experimental fracture loads and the fracture angles of the specimens are obtained. Because of the linear elastic behavior of the spruce wood, the point stress (PS) and mean stress (MS) methods, both being stress-based criteria, are used in combination with the Virtual Isotropic Material Concept (VIMC) for predicting the fracture loads and the fracture angles. By employing the VIMC, the spruce wood as an orthotropic material is modeled as a homogeneous and isotropic material with linear elastic behavior. The stress components required for calculating the experimental values of notch stress intensity factors are obtained by finite element (FE) analyses of the test configuration using commercial FE software from the fracture loads obtained experimentally. The discrepancies between the experimental and theoretical results of the critical notch stress intensity factors are obtained between −12.1% and −15% for the PS criterion and between −5.9% and −14.6% for the MS criterion, respectively. The discrepancies related to fracture initiation angle range from −1.0% to +12.1% for the PS criterion and from +1.5% to +12.2% for the MS criterion, respectively. Thus, both the PS and MS models have good accuracy when compared with the experimental data. It is also found that both failure criteria underestimate the fracture resistance of spruce wood under mixed-mode I/III loading.