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A practical technique was applied to fabricate MoWS 2 nanocomposite through a one-pot hydrothermal method for use as the electrocatalyst. The characterization of MoWS 2 nanocomposite was investigated by several techniques to identify the size, crystal structure, and elemental composition. MoWS 2 nanocomposite exhibited a unique and well-defined hierarchical structure with neatly and densely piled nanopetals acting as the active sites in the electrocatalytic reactions. A carbon screen-printed electrode (CSPE) modified with interesting MoWS 2 nanopetals (MoWS 2 /CSPE) was constructed. Subsequently, the electrochemical oxidation of morphine on fabricated MoWS 2 /CSPE was studied. Experimental results confirm that under optimized conditions, the maximum oxidation current of morphine occurs at 275 mV in the case of MoWS 2 /CSPE that is around 100 mV more negative than that observed in the case of the unmodified CSPE and about 2.6 times increase was observed for the oxidation peak current. The analytical approach was obtained by differential pulse voltammetry in accordance with the relationship between the oxidation peak current and the morphine concentration. The oxidation peak currents for morphine were found to vary linearly with its concentrations in the range of 4.8 × 10 -8 -5.05 × 10 -4  M with the detection limit of 1.44 × 10 -8  M. Two completely separated signals occured at the potentials of 275 mV and 920 mV for oxidation of morphine and tramadol at the surface of MoWS 2 /CSPE which are sufficient for determination of morphine in the presence of tramadol. The presence of morphine was also detected in real samples using the introduced approach. Graphical abstract Schematic representation of fabrication of the MoWS 2 nanocomposite through a one-pot hydrothermal method for use as the electrocatalyst. A carbon screen-printed electrode was modified with MoWS 2 nanocomposite. Subsequently, the electrochemical oxidation of morphine on the fabricated electrode was studied.

Rationale: Autism spectrum disorder (ASD), the fastest growing neurodevelopmental disorder, is characterized by social deficits, repetitive/stereotypic activity, and impaired verbal and nonverbal communication and is commonly diagnosed at early stages of life. Based on the excitatory-inhibitory imbalance theory of autism, some recent animal experiments have reported amelioration in autistic-like phenotypes in adult animals following acute treatment of NMDA antagonists. However, we suggested the neonatal period as a critical period for NMDA antagonist intervention., Objectives: This experiment was designed to determine the role of postnatal MK-801, an NMDA receptor blocker, in the prenatal valproic acid (VPA) rat model of ASD., Methods: The model of autism was induced by subcutaneous administration of valproic acid (600 mg/kg) to pregnant rats at gestational day 12.5. The effects of MK-801 (0.03 mg/kg, from postnatal day 6-10) in correcting ASD-associated behaviors in male offspring were assessed by open-field, three-chambered social interaction tests. Moreover, the nociceptive threshold was measured by tail flick and hot plate. Behavioral tests were performed on PND 55-60. Nissl staining was performed to confirm the safety of 0.03 mg/kg MK-801 for the brain., Results: We reported that MK-801 rescued social deficits, repetitive behaviors (self-grooming), anxiety-related behavior, and the low nociceptive threshold in the VPA-treated rats. Further, histological examination showed that there were no significant differences among all the groups in terms of the neuronal survival rate., Conclusions: Our results showed that postnatal low-dose MK-801 improved ASD-associated behaviors in the VPA-treated rats and that early exposure to NMDA antagonist resulted in permanent changes in adult behavior.

A fluorometric method is presented for sensitive deternination of microRNA. It is making use of carbon dots (C-dots) loaded with a DNA probe as fluorophore and MnO 2 nanosheets as the quenching agent. The blue-green fluorescence of the DNA-loaded C-dots is quenched by the MnO 2 nanosheets, but restored on binding target microRNA-155. The maximum excitation wavelength and the maximum emission wavelength of C-dots are at 360 nm and 455 nm, respectively. Fluorescence correlates linearly with the log of the microRNA-155 concentration in two ranges, viz. from 0.15 to 1.65 aM and from 1.65 to 20 aM. The detection limit is as low as 0.1 aM. The assay can discriminate between fully complementary and single-base mismatch microRNA. The assay displayed high specificity when used to detect MCF-7 breast cancer cells which can be detected in concentrations from 1000 to 45,000 cells·mL -1 , with a 600 cells·mL -1 detection limit. The method was applied to the analysis of serum samples spiked with microRNA, and satisfactory results were acquired. Graphical abstract Schematic of a fluorometric sensing platform for miRNA-155. The method relies on a FRET process between C-dots and MnO 2 nanosheets. This strategy has a practical application for detection of miRNA in cell lines and biological fluids.

Background: Leishmania major is a causative agent of zoonotic cutaneous leishmaniasis in the center of Iran, Abarkouh district. Molecular characterization and precise incrimination of Leishmania species was carried out to perform controlling measurements and to design treatment programs for zoonotic cutaneous leishmaniasis., Methods: All smears isolated from ulcers of suspected patients were examined under a light microscope and graded for amastigotes frequency. Extraction of DNA, PCR, RFLP and sequencing of ITS-rDNA genotype were done to increase the efficacy of Leishmania parasites identification at their species-specific level and to detect any Leishmania infections within., Results: Humans were found to be infected with L. major with high infection frequency and also Leishmania tropica was identified with low occurrence for the first time as non-native species using molecular analyses. The rates of infections was considerable with microscopic observation (n = 65, 73%) out of 89 smears prepared from suspected patients. Molecular analyses showed that the density of L. major was significantly higher (n = 48, 53.93%) than L. tropica (n = 4, 4.49%) (Mann-Whitney U test: p < 0.05) and two samples (2.25%) remained ambiguous after several sequencing. L. major did not have diversity with two common haplotypes but L. tropica were found to exhibit high diversity with three novel haplotypes., Conclusion: L. major was considered the causative agent of leishmaniasis in the region, but the identification of a non-native L. tropica revealed the importance of further isolation of Leishmania parasites following molecular analyses and confirmation, and also revealed the importance of further isolation of Leishmania parasites from patients of the field areas who do not have easily access to health care centers for specialized treatment strategies., (Copyright © 2018 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.)

Polycyclic aromatic hydrocarbons (PAHs), tobacco-specific nitrosamines (TSNAs) and aromatic amines are carcinogens present in cigarette smoke. These compounds are distributed in the human body and they could be transferred to the foetus during the pregnancy. Placenta is the main barrier to these toxic compounds and its study is the objective of this work. A method based on solid-phase extraction (SPE) with ultra-performance liquid chromatography-tandem quadrupole-time-of-flight mass spectrometry (UPLC-QTOF-MS) has been examined and optimized for the analysis of 9 target analytes (4 tobacco-specific nitrosamines and some of their metabolites, 3 aromatic amines, nicotine and cotinine) in 26 placenta samples from smoking and non-smoking women. Limits of detection (LODs) were in the range of 3-27ng/g of placenta. Nicotine, cotinine, N-nitrosoanatabine (NAT) and 4-(methylnitrosamino)-1- (3-pyridyl)-1-butanone (NNK) metabolite, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) were detected in the placenta samples of smoking woman. Nicotine was detected in 3 out of 8 placentas from smoking women, always below the limit of quantification (88ng/g). This could be expected, as the half-life of nicotine in the body is limited to about 0.5-3h. Cotinine, the main metabolite from nicotine, was detected in all placentas from smoking women at concentrations between 17.2 and 61.8ng/g, reaching the highest values for those women that smoked the highest number of cigarettes. NAT and NNAL were detected in all placentas from smoking women, always below the limit of quantification (40ng/g and 33ng/g respectively)., (Copyright © 2017 Elsevier B.V. All rights reserved.)

We have described a simple and reliable colorimetric method for the sensing of biothiols such as cysteine, homocysteine, and glutathione in biological samples. The selective binding of chitosan capped silver nanoparticles to biothiols induced aggregation of the chitosan-Ag NPs. But the other amino acids that do not have thiol group cannot aggregate the chitosan-Ag NPs. Aggregation of chitosan-Ag NPs has been confirmed with UV-vis absorption spectra, zeta potential and transmission electron microscopy images. Under optimum conditions, good linear relationships existed between the absorption ratios (at A 500 /A 415 ) and the concentrations of cysteine, homocysteine, and glutathione in the range of 0.1-10.0μM with detection limits of 15.0, 84.6 and 40.0nM, respectively. This probe was successfully applied to detect these biothiols in biological samples (urine and plasma)., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Leishmaniasis as an emerging and reemerging disease is increasing worldwide with high prevalence and new incidence in recent years. For epidemiological investigation and accurate identification of Leishmania species, three nuclear and mitochondrial genes (ITS-rDNA, Hsp70, and Cyt b ) were employed and analyzed from clinical samples in three important Zoonotic Cutaneous Leishmaniasis (ZCL) foci of Iran., Methods: In this cross-sectional/descriptive study conducted in 2014-15, serous smears of lesions were directly prepared from suspected patients of ZCL in Turkmen in northeast, Abarkouh in center and Shush district in southwest of Iran. They were directly prepared from suspected patients and DNA was extracted. Two nuclear genes of ITS-rDNA, Hsp70 and one mitochondrial gene of Cyt b within Leishmania parasites were amplified. RFLP was performed on PCR-positive samples. PCR products were sequenced, aligned and edited with sequencher 4.1.4 and phylogenic analyses performed using MEGA 5.05 software., Results: Overall, 203 out of 360 clinical samples from suspected patients were Leishmania positive using routine laboratory methods and 231 samples were positive by molecular techniques. L. major L. tropica , and L. turanica were firmly identified by employing different molecular genes and phylogenic analyses., Conclusion: By combining different molecular genes, Leishmania parasites were identified accurately. The sensitivity and specificity three genes were evaluated and had more advantages to compare routine laboratory methods. ITS-rDNA gene is more appropriate for firm identification of Leishmania species., Competing Interests: Conflict of Interest The authors declare that there is no conflict of interest.

Plasmodium vivax apical membrane antigen-1(PvAMA-1) is a surface protein with polymorphic sites. This study was aimed to analyze the polymorphic amino acid residues at PvAMA-1 in different infected age groups. 92 blood samples were collected from the south and southeast of Iran. The DNA coding for the domain I (DI), DII, and partial DIII of this antigen was amplified by Nested-PCR, and sequenced. Nucleotide mutations were found in 49 sites and based on the amino acid sequence, 30 variable sites were detected. Age distribution of malaria cases showed that the majority of the patients were between 10 to 30 years old. The scattering plot haplotypes by age showed an increasing incidence rate with age during childhood, whereas, incidence was the lowest in patients under five years old. Comparison of the polymorphic sites of PvAMA-1 in Iranian isolates with those found in other geographic regions of the world indicated nine common variable positions. In addition, a significant dependence was found between some particular substitutions and age categories. Dependence between particular substitutions and age groups suggests that certain residues in AMA-1 are responsible for clinical attacks in different ages, likely as a result of host immune pressure. The crystal structure of the PvAMA-1 showed that the amino acid substitutions that changed the protein charge were exclusively located in loops and turns where, the interactions with antibodies could occur. These data provide the necessary information for an AMA-1 based malaria vaccine design to be effective across all ages., Competing Interests: The authors declared no conflict of interest.

Background: Interest in Tatera indica rodent arises mostly because it is believed that this species is survived among four subspecies reported from Iran, two of which exist in Khuzestan Province. In addition, it might has a role as reservoir hosts of zoonotic cutaneous leishmaniasis in the transmission of Leishmania major in some of the widespread Asian foci including southwestern Iran., Methods: Diagnostic morphological and molecular markers for T. indica were sought by characterizing from individual specimens, such as some taxonomic features and mitochondrial cytochrome b gene that had previously proven useful for the taxonomy of rodents. Wild rodents were caught using live wooden and wire traps. The specimens were identified morphologically using external criteria and molecularly by sequencing of Cyt b gene and phylogenetic analyses., Results: Forty one T. indica were collected and identified morphologically in Khuzestan Province, Iran. Two morphotypes of T. indica were found and classified but sequencing and phylogenetic analyses of mitochondrial Cyt b gene did not support any subspecies between two morphotypes of T. indica. Because all 21 sequences of both morphotypes of T. indica had no variation with only one common and novel haplotype (GenBank accession No KP001566)., Conclusion: This is the first time that T. indica was characterized molecularly in Iran. There is no molecular evidence for T. indica morphotypes or subspecies, and so a population genetics approach using several polymorphic genes might be employed using species-specific molecular markers. In addition, more specimens of T. indica species in large geographical locations should be tested.

Special characteristics of care environments have always presented nurses with some challenges. One particular situation is futile care, which is frequently accompanied by countless moral and legal challenges. The dominant atmosphere in futile care may cause moral distress to nurses and lead to a sense of guilt, pain, suffering, job dissatisfaction, and eventually cause nurses to leave the job. This descriptive-analytical study attempted to investigate the relationship between futile care and moral distress in intensive care nurses. Study subjects were 300 nurses in intensive care units in Kerman, Iran and were selected by convenience sampling based on inclusion criteria. Study tools included Corley's 21-item questionnaire on moral distress and a researcher-made 17-item questionnaire on futile care. Data analysis was performed using SPSS version 16 and suitable analytical and descriptive tests. The results showed a significantly positive relationship between moral distress and futile care (P = 0.03, r = 0.4). Based on the obtained results, futile care can create conditions that may lead to moral distress in nurses and therefore strategies should be devised to prevent these conditions. Moreover, distress in nurses should be identified by periodical counseling so that it can be managed more efficiently.

Despite increasing interest in the attentional biases of pain patients towards pain-related stimuli, there have been no investigations of whether the main caregivers of chronic pain patients also selectively attend to pain-related information. We compared the attentional biases to painful or happy faces of 120 chronic pain patients, 118 caregivers, and 50 controls. Analyses found that both patients and caregivers demonstrated biases towards painful faces that were not observed in control participants or to happy faces. Those patients and caregivers who were high in fear of pain demonstrated greater biases than those low in fear of pain, and the biases of the high-in-fear-of-pain group differed significantly from zero. When sub-groups of caregivers were compared, it was found that biases towards painful faces were not observed for those caregivers who accurately identified the level of pain the patient currently reported. In contrast, those caregivers who overestimated or underestimated the patients' pain demonstrated biases that were significantly greater than zero. These results add to the growing weight of evidence suggesting that biases towards pain-related stimuli are observed in chronic pain patients, but that the nature of the stimuli is important. In addition, the results suggest that caregivers, particularly those who either under- or overestimate the level of pain that the patient reports, also demonstrate similar biases. Future research should investigate the links between caregivers' biases and the way in which caregivers respond to pain., (Copyright © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.)