Fabrication of hierarchical flower-like WO3 nanoparticles for effective metal ions sensing and catalytic degradation of organic dyes.

In this work, we report on the synthesis of flower-like tungsten oxide nanoparticles (WO3 NPs) using a simple precipitation method. This paper reports a simple method for synthesizing flower-like WO3 NPs, which can be used for environmentally treating hazardous organic pollutants. The photocatalytic degradation of model artificial Orange II and Congo red was assessed under natural sunlight irradiation. The surface morphologies, crystallinity, and binding energy of the synthesized WO3 NPs were determined. The synthesized WO3 NPs exhibited good photodegradation percentages of approximately Orange II (97.6%) and Congo red dye (98.2%) after 120 min of irradiation. Furthermore, the WO3 NPs maintained their degradation ability for up to three cycles. In addition, WO3 NPs were examined in different metal ions sensing (Hg2+, Fe2+, Cu2+, Ni2+, and Cd2+) in an aqueous solution. The results showed that the WO3 NPs exhibited excellent Cd2+ ion sensing. Based on the investigations, WO3 NPs proved to be an efficient photocatalyst and hold promise as the best material for future applications in preventing water pollution.

Development of luminescence carbon quantum dots for metal ions detection and photocatalytic degradation of organic dyes from aqueous media.

In the present study, fish scale waste was used for the organic synthesis of luminescence CQDs by the hydrothermal method. The impact of CQDs on improved photocatalytic degradation of organic dyes and metal ions detection is examined in this study. The synthesized CQDs had a variety of characteristics that were detected, such as crystallinity, morphology, functional groups, and binding energies. The luminescence CQDs showed outstanding photocatalytic effectiveness for the destruction of methylene blue (96.5%) and reactive red 120 dye (97.8%), respectively after 120 min exposure to visible light (420 nm). The high electron transport properties of the CQDs edges, which make it possible to efficiently separate electron-hole pairs, are attributed to the enhanced photocatalytic activity of the CQDs. These degradation results prove that the CQDs are the outcome of a synergistic interaction between visible light (adsorption); a potential mechanism is also suggested, and the kinetics is analyzed to use a pseudo-first-order model. Additionally, the metal ions detection of CQDs was studied by various metal ions (Hg2+, Fe2+, Cu2+, Ni2+, and Cd2+) in an aqueous solution and results revealed that the PL intensity of CQDs in presence of cadmium ions decreased. Studies show that the organic fabrication of CQDs are effective photocatalyst and may one day serve as the ideal material to reduce water pollution.

Effects of Antioxidant Combinations on the Renal Toxicity Induced Rats by Gold Nanoparticles.

This study investigated some possible mechanisms underlying the nephrotoxic effect of gold nanoparticles (AuNPs) in rats and compared the protective effects of selected known antioxidants-namely, melanin, quercetin (QUR), and α-lipoic acid (α-LA). Rats were divided into five treatment groups (eight rats per group): control, AuNPs (50 nm), AuNPs + melanin (100 mg/kg), AuNPs + QUR (200 mg/kg), and AuNPs + α-LA (200 mg/kg). All treatments were administered i.p., daily, for 30 days. AuNPs promoted renal glomerular and tubular damage and impaired kidney function, as indicated by the higher serum levels of creatinine (Cr), urinary flow, and urea and albumin/Cr ratio. They also induced oxidative stress by promoting mitochondrial permeability transition pore (mtPTP) opening, the expression of NOX4, increasing levels of malondialdehyde (MDA), and suppressing glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT). In addition, AuNPs induced renal inflammation and apoptosis, as evidenced by the increase in the total mRNA and the cytoplasmic and nuclear levels of NF-κB, mRNA levels of Bax and caspase-3, and levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Treatment with melanin, QUR, and α-lipoic acid (α-LA) prevented the majority of these renal damage effects of AuNPs and improved kidney structure and function, with QUR being the most powerful. In conclusion, in rats, AuNPs impair kidney function by provoking oxidative stress, inflammation, and apoptosis by suppressing antioxidants, promoting mitochondrial uncoupling, activating NF-κB, and upregulating NOX4. However, QUR remains the most powerful drug to alleviate this toxicity by reversing all of these mechanisms.

Concomitant Sub-Chronic Administration of Small-Size Gold Nanoparticles Aggravates Doxorubicin-Induced Liver Oxidative and Inflammatory Damage, Hyperlipidemia, and Hepatic Steatosis.

This study examined the effect of gold nanoparticles (AuNPs) on doxorubicin (DOX)-induced liver damage and steatosis in rats and tested its effect mechanism. Wistar male rats were divided into four groups (each of eight rats) as control, AuNPs (50 µL of 10 nm), DOX (15 mg/kg; 3 mg/kg/week), and DOX + AuNPs-treated rats. DOX is known to induce fasting hyperglycemia and hyperinsulinemia in treated rats. Individual treatment of both DOX and AuNPs also promoted liver damage, increased circulatory levels of ALT and AST, and stimulated serum and liver levels of TGs, CHOL, LDL-c, and FFAs. They also stimulated MDA, TNF-α, and IL-6, reduced GSH, SOD, HO-1, and CAT, upregulated mRNA levels of Bax and caspases-3 and -8 and downregulated mRNA levels of Bcl2 in the livers of rats. However, while DOX alone reduced hepatic levels of PPARα, both AuNPs and DOX stimulated mRNA levels of SREBP1, reduced the mRNA, cytoplasmic and nuclear levels of Nrf2, and increased mRNA, cytoplasmic, and nuclear levels of NF-κB. The liver damage and the alterations in all these parameters were significantly more profound when both AuNPs and DOX were administered together. In conclusion, AuNPs exaggerate liver damage, hyperlipidemia, and hepatic steatosis in DOX-treated rats by activating SREBP1 and NF-κB and suppressing the Nrf2/antioxidant axis.

Leptin induces a contracting effect on guinea pig tracheal smooth muscle via the Ob-R receptor mechanism: novel evidence.

The purpose of this study was to explore the potential contracting effect of leptin on isolated guinea pig tracheal smooth muscle (TSM), the possible mechanism, and the impact of epithelium denudation or allergen sensitization, respectively. An in vitro experiment investigated the effect of leptin at a concentration of 250-1000 nmol/L on isolated guinea pig TSM with an intact or denuded epithelium. Ovalbumin and IgE were used to test the impact of active and passive sensitization. The isolated TSM strips were incubated in Krebs solution and aerated with carbogen (95% O2 and 5% CO2) via an automated tissue organ bath system (n = 4 for each group). Isometric contractions were recorded digitally using iox2 data acquisition software. The possible mechanism of leptin-induced TSM contraction was examined by preincubation with leptin receptor (Ob-R) antagonist. Leptin had significant concentration-dependent contraction effects on guinea pig TSM (p < 0.05). Epithelium denuding and active or passive sensitization significantly increased the potency of the leptin. Preincubation with a leptin receptor (Ob-R) antagonist significantly reduced the contraction effects, suggesting an Ob-R-mediated mechanism. Leptin had a contracting effect on airway smooth muscles potentiated by either epithelium denuding or sensitization, and the Ob-R mechanism was a possible effect mediator.

Relaxant effect of ghrelin on guinea pig isolated tracheal smooth muscle: role of epithelial NO and PGE2.

This study aimed at investigating the potential ghrelin relaxing effect on guinea pig isolated tracheal smooth muscle (TSM). Using an in vitro experimental approach, the physiological role of the airway epithelium on smooth muscle relaxation has been investigated by analyzing the dose-response curves for carbachol- or histamine-induced contractions on epithelium intact versus denuded tracheal tissue. The relaxant effect of ghrelin (5-200 µmol/L) then investigated on carbachol-contracted, non-sensitized, and ovalbumin (OVA)-sensitized guinea pig TSM with an intact or denuded epithelium. The isolated TSMs from identical guinea pigs were incubated in Krebs solution aerated with 95% O2 and 5% CO2 through an automated tissue organ bath system (n = 6 for each group). The ghrelin relaxation mechanism was assessed by adding L-NAME, indomethacin, and YIL-781 for GHS-R1 into the tissue chamber. The spasmogens carbachol and histamine have shown a significantly higher contracting effect on epithelium-denuded than in epithelium-intact TSM confirmed by the significantly higher mean pEC50 of both agonists on the epithelium-denuded trachea (p < 0.05). Ghrelin has shown a concentration-dependent relaxing effect on carbachol-contracted TSM (r = 0.96, p = 0.00). The effect was more evident in the intact non-sensitized than in epithelium-denuded or OVA-sensitized groups (p < 0.05). Preincubation with nitric oxide (NO) and prostaglandin E2 (PGE2) inhibitors has significantly reduced the ghrelin-induced relaxation on epithelium-intact TSM suggesting an epithelium-dependant mechanism. However, GHS-R1a antagonist has also succeeded to reduce ghrelin relaxant effect, which needs further clarification. Ghrelin proved to have a potential TSM relaxant effect possibly through epithelium-dependant mechanisms involving NO and PGE2.

Epidemiology of group A rotavirus infection after the introduction of monovalent vaccine in the National Immunization Program of Saudi Arabia.

This study aimed to investigate the prevalence of group A rotavirus (RVA) gastroenteritis and the distribution of the RVA genotypes as well as to determine a possible change in the age of occurrence of the RVA infection in the first 2 years after Rotarix® vaccine introduction in Saudi Arabia. This descriptive study included 850 hospitalized children <5 years of age with acute gastroenteritis (AG) between October 2013 and September 2015. Overall, 78 (9.2%) children were positive for RVA during the study period with a positivity rate ranging from 11.3% in the first year of the study to 6.8% in the second year. G1 (47.4%) was the predominant G type, followed by G2 (28.2%) and G9 (10.3%). The most common P type was P[8] (69.2%) followed by P[4] (25.6%). The decrease in the prevalence of G1P[8] from 51% to 37.1% was associated with an increase in the prevalence of G2P[4] from 21.6% to 33.3% during the 2-year study period. This study demonstrated a significant decrease in the prevalence of RVA-AG cases in the first 2-year period after vaccine introduction, especially in the age group between 1 and 12 months, and a reduction in the circulation of G1P[6]. The parallel rise and spread of G2P[4] in post-vaccination period might pose an impact to long-term vaccine efficacy. Continued surveillance studies in different Saudi regions are crucial to document the effectiveness of Rotarix® vaccine and evaluate the potential emergence of rare/novel RVA genotypes. J. Med. Virol. 89:429-434, 2017. © 2016 Wiley Periodicals, Inc.

The changes in serum and whole blood rheological properties of rabbits during the progression of atherosclerosis.

This study aimed to evaluate the role of zinc (Zn)-supplemented with high cholesterol diet (HCD) on the serum and whole blood rheological properties of rabbits fed a HCD. Twenty-four New Zealand white rabbits were divided into three groups. The HCD group was fed a diet with 1.0% cholesterol and 1.0% olive oil. The HCD + Zn group was fed a diet with 1.0% cholesterol, 1.0% olive oil, and Zn. Blood viscosity, shear stress, and torque (%) were measured at shear rates ranging from 225 to 1875 s-1 for serum and 75-900 s-1 for whole blood. Serum viscosity and shear stress in HCD rabbits were significantly higher at all shear rates compared to controls; while whole blood viscosity and shear stress in HCD rabbits were significantly lower at all shear rates compared to controls. Viscosity and shear stress in both serum and whole blood from rabbits in the HCD + Zn group returned to normal values at all shear rates. The Zn supplemented to HCD rabbits, delays the progression of atherosclerosis. Changes in blood serum viscosity could reflect changes in non-clotting proteins, glucose, nutrients and trace elements; while changes in whole blood viscosity could result from changes in hematocrit, hemoglobin, and erythrocyte count. One of the factors responsible for increasing the serum viscosity values of HCD rabbits might be attributed to increase in Fe and decrease in Zn levels in the blood serum.

The effects of intraperitoneal administration of gold nanoparticles size and exposure duration on oxidative and antioxidants levels in various rat organs.

As one of the toxic mechanism of nanoparticles (NPs), the reactive oxygen species (ROS) generation which has been widely studied. Nevertheless, the link between GNPs and antioxidant and oxidative stress markers has not been well established. The effects of gold nanoparticles (GNPs) size and exposure duration on antioxidant and oxidative stress markers including reduced glutathione (GSH), super oxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), total antioxidant capacity and malondialdehyde (MDA) were evaluated in different rat organs. Adult male Wistar-Kyoto rats were randomly divided into 6 groups of 5 animals each. One group served as control and received vehicle only. The 10 nm GNPs were used in this study. The GNPs electron density and homogeneity in shape and size was evaluated. Dose of 50 µl of 10 nm GNPs in aqueous solution were administered to animals via intraperitoneal administration daily for exposure duration of 3 or 7 days. The rats were sacrificed 24 h after the last injection of GNPs. The specimens of liver, lung, kidney and heart were collected for biochemical analyses. The GPx, total antioxidant capacity, GSH and MDA levels significantly increased after administration of 10 nm GNPs for exposure duration of 3 and 7 days in the organs of rats compared with the control while the GR and SOD levels significantly decreased. The GNPs have the potential to interact with the biological system and cause undesirable effects. One of these damaging effects could be the disturbance in the natural balance between oxidative stress and antioxidant defense indices, which in turn can lead to various pathological effects. The changes in antioxidant and oxidative stress markers might be attributed to the production of ROS.

The effects of gamma-radiation on red blood cell corpuscles and dimensional properties in rats.

In an attempt to understand the toxicity and the potential role of gamma-radiation as a therapeutic tool, the effects of different Gamma-radiation doses on haematological and dimensional properties of rats' blood were investigated in vivo. 60 healthy male Wistar-Kyoto rats were used, which were randomly divided into five groups, 4 Gamma-radiated rat groups (1st group was radiated with five Gamma-radiation dose, 2nd group 25 Gy; 3rd group with 50 Gy, 4th group with 100 Gy, and 5th group was control). Different haematological and dimensional parameters were measured using the standard haematological technique. A significant decrease in red blood cells (RBCs) count, haemoglobin (HGB), and haematocrit (HCT) was observed compared with the control. While a significant increase in mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC), red distribution width (RDW) were observed compared with the control. This study suggested that low RBCs, HGB, and HCT might produce anemia and cessation of erythrocytes production in the bone marrow. Moreover, the RBCs size increase might be attributed to changes in the morphology and deformability of RBCs, which was confirmed by a slightly increase in RDW.

Gamma irradiation effects on the electrical properties of gold nanoparticles.

Gold nanoparticles (AuNPs) offer a great promising in biomedical applications and their size has been shown to be important parameters that affect the particles uptake and cellular imbibition. The presented dielectric data indicates that AuNPs have well characteristic dispersion in the alpha relaxation region. The presented work aims to characterize and improve the quality control of AuNPs, define the benefit combination effects of size and gamma irradiation on the properties of AuNPs dielectric relaxation spectroscopy.

Effect of incubating egg exposure to magnetic field on the biophysical blood properties of newly-hatched chicks.

Due to widespread of human exposure to electromagnetic fields, there has been increasing public concern about the potential health risks from low-frequency electromagnetic fields; ELF-EMF. The magnetic fields (MFs) affects functions of the living organisms, such as DNA synthesis and ion transportation through the cell membranes. In the present work, the effects of short-term exposure to magnetic fields (MFs) prior to incubation were investigated on the biophysical blood properties of chicks hatched from layer-type breeder eggs. The eggs were exposed to a MF of 0.75 mT at 50 Hz for 20, 40 and 60 min before incubation. This study was performed by measuring the dielectric relaxation of hemoglobin (Hb) molecules and the membrane solubility of red blood cells (RBCs) using the non-ionic detergent octylglucoside. Exposure of the eggs to a MF increased the conductivity of the Hb molecules. The pronounced increase in the conductivity of the exposed eggs might be attributed to an increase in the surface charge of the Hb macromolecules, resulted from the formation of highly active molecular species. This speculation can be supported by the increase in the relaxation time of the exposed groups. The solubilization process of the RBC membrane indicates a loss in the mobility of RBCs in the blood of hatching chicks.

The Protective Effect of α-Lipoic Acid against Gold Nanoparticles (AuNPs)-Mediated Liver Damage Is Associated with Upregulating Nrf2 and Suppressing NF-κB.

This study examined if regulating the keap-1? Nrf2 antioxidant pathway mediated gold nanoparticles (AuNPs) induced liver damage, and examined the protective effect of co-supplement of α-lipoic acid (α-LA). Rats were separated into 4 groups (n = 8/each) as control, α-LA (200 mg/kg), AuNPs (5 µg/2.85 × 1011), and AuNPs (5 µg/2.85 × 1011) + α-LA (200 mg/kg). After 7 days, AuNPs induced severe degeneration in the livers of rats with the appearance of some fatty changes. In addition, it increased serum levels of alanine aminotransferase (ALT) and gamma-glutamyl transferase (É£-GTT), and aspartate aminotransferase (AST), as well as liver levels of malondialdehyde (MDA). Concomitantly, AuNPs significantly depleted hepatic levels of total glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) but increased hepatic levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). It also reduced mRNA levels of B-cell lymphoma 2 (Bcl2) and heme oxygenase-1 (HO-1) but significantly increased those of Bax and cleaved caspase-3, as well as the ratio of Bax/Bcl2. In addition, AuNPs enhanced the total and nuclear levels of NF-κB p65 but reduced the mRNA and total and nuclear protein levels of Nrf2. Of note, AuNPs did not affect the mRNA levels of keap-1. All these events were reversed by α-LA in the AuNPs-treated rats. In conclusion, α-LA attenuated AuNPs-mediated liver damage in rats by suppressing oxidative stress and inflammation, effects that are associated with upregulation/activation of Nrf2.

The changes in various hydroxyproline fractions in aortic tissue of rabbits are closely related to the progression of atherosclerosis.

BACKGROUND: The most important function of collagen and elastin is to induce several mechanical parameters which are known to play a dominant role in governing mechanical properties of the blood vessels. The aortic tissue of rabbit is one of the important sources of collagen and elastin. The effects of high fat diet (HFD) on the hydroxyproline (Hyp) fractions in serum and aortic tissues of rabbits and collagen content in the aortic tissues of rabbits have not been documented before. The present study was undertaken to investigate the changes in Hyp fractions in serum and aortic tissues of rabbits and collagen content in the aortic tissues of rabbits during the progression of atherosclerosis. The atherosclerotic model used in this study was the New Zealand white rabbit (male; 12 weeks old). Twenty five rabbits were individually caged, and divided into control group (NOR; n = 10) and HFD group (CHO; n = 15). The control group was fed (100 g/day) of normal (NOR) diet for a period of 15 weeks. The HFD group was fed normal diet supplemented with 1.0% cholesterol plus 1.0% olive oil (100 g/day) for the same period of time. RESULTS: We found that the TC, LDLC, and TG (mg/dl) were significantly (p < 0.001) increased in HFD rabbits compared with control rabbits with percentage normalized changes of 1198%, 1591%, and 710%, respectively. The peptide-bound Hyp in the serum was significantly (P < 0.05) increased in HFD rabbits compared with control rabbits with percentage normalized change of 517% while it significantly (P < 0.01) decreased in aortic tissues of HFD rabbits compared with control rabbits with percentage normalized change of 65%. The protein-bound Hyp in the serum was significantly (P < 0.01) increased in HFD rabbits compared with control rabbits with percentage normalized change of 100%; the protein-bound Hyp in the aortic tissues of control rabbits was 235.30 +/- 55.14 (Mean +/- SD) while it was not detectable (ND) in HFD rabbits. Total serum Hyp showed no significant (P < 0.05) change in HFD rabbits compared with control rabbits while it was significantly (P < 0.05) decreased in aortic tissues of HFD rabbits compared with control rabbits with percentage normalized change of 73%. The total collagen was significantly (p < 0.01) decreased in aortic tissues of HFD rabbits compared with control rabbits with percentage normalized change of 73% which was supported by histological study. CONCLUSIONS: These results suggest that percentage decrease in various Hyp fractions in aortic tissue of HFD rabbits are closely related to percentage decrease of collagen content in aortic tissues of HFD rabbits. These results also suggest that it may be possible to use the changes in various Hyp fractions in aortic tissues of rabbits as an important risk factor during the progression of atherosclerosis.

Gestational Exposure to Synthetic Steroid Hormones Impaired Sperm Quantity and Quality in Wistar Rats.

This study was designed to investigate the effect of prenatal exposure to synthetic sex steroid on sperm quantity and quality, relative testicular and epididymal weights, and reproductive hormones level in adult Wistar rats. Forty male Wistar rats were divided into two groups: a test group (n = 20) that included mature rats that were born to dams exposed to gestational treatment with hydroxyprogesterone and a control group (n = 20) that included mature rats born to untreated dams. Compared to the control group, the test group showed a significant reduction in the sperm count, viability and motility, relative testicular and epididymal weights together with increased abnormal spermatozoa (p < 0.001). The reproductive hormonal assay revealed significantly lower serum testosterone and higher levels of FSH and LH among the test groups compared to the control (p < 0.05 for all). Prenatal exposure to synthetic progesterone negatively affected sperm production and function, relative testicular and epididymal weights, and reproductive hormone levels.

Serum Ghrelin Levels in Saudi Obese Asthmatic School-Children-Correlation with Interleukin-4, Interleukin-5, and Interleukin-21.

Ghrelin is a peptide hormone with direct or indirect effects on obesity and asthma. More data are required to understand the effect of ghrelin on the control and pathogenesis of these diseases. The aim of this study was to evaluate ghrelin levels in selected groups of children to identify the association between serum ghrelin, obesity, and the severity of asthma. The study included 401 school children selected from the Najran area and grouped into non-obese asthmatics, obese asthmatics, obese non-asthmatics and controls (non-obese non-asthmatics). Blood levels of ghrelin, interleukin (IL)-4, IL-5 and IL-21 were determined by ELISA. The mean ghrelin values were insignificantly increased in obese children compared with non-obese children. The highest blood ghrelin values were in the non-obese asthmatic group. Serum ghrelin, IL-4 and IL-21 levels were significantly increased in asthmatic children compared with non-asthmatic children (p < 0.05), and there were significant positive correlations between ghrelin and IL-4, IL-5, and IL-21 in asthmatic children. Furthermore, ghrelin, IL-4, and IL-21 levels were significantly higher in uncontrolled asthmatics compared with controlled-asthmatic children (p < 0.05). Asthma was the only significant risk factor for high ghrelin values. This study provides evidence supporting the anti-inflammatory role of ghrelin in the pathogenesis of asthma. Asthma might be considered as an important determinant of high ghrelin values in children.

Systemic Type I IFN Inflammation in Human ISG15 Deficiency Leads to Necrotizing Skin Lesions.

Most monogenic disorders have a primary clinical presentation. Inherited ISG15 deficiency, however, has manifested with two distinct presentations to date: susceptibility to mycobacterial disease and intracranial calcifications from hypomorphic interferon-II (IFN-II) production and excessive IFN-I response, respectively. Accordingly, these patients were managed for their infectious and neurologic complications. Herein, we describe five new patients with six novel ISG15 mutations presenting with skin lesions who were managed for dermatologic disease. Cellularly, we denote striking specificity to the IFN-I response, which was previously assumed to be universal. In peripheral blood, myeloid cells display the most robust IFN-I signatures. In the affected skin, IFN-I signaling is observed in the keratinocytes of the epidermis, endothelia, and the monocytes and macrophages of the dermis. These findings define the specific cells causing circulating and dermatologic inflammation and expand the clinical spectrum of ISG15 deficiency to dermatologic presentations as a third phenotype co-dominant to the infectious and neurologic manifestations.

Parents' Knowledge, Attitudes and Practices on Antibiotic Use by Children.

BACKGROUND AND OBJECTIVE: Deficient knowledge on antibiotics causes misuse. This study aimed to investigate parents' knowledge, attitudes and practices on antibiotic use by children in various cities of Saudi Arabia. METHODS: This cross-sectional study was carried out using a previously validated questionnaire. The questionnaire was translated into Arabic and hosted on Google Forms. Parents of children aged ≤14 years, whose contact details were available with the author, were contacted and requested to participate in the study. For those who agreed to participate, the Google Forms link was shared through WhatsApp between July and August 2016. The respondents were also encouraged to share the link with contacts who had children aged ≤14 years. Descriptive and inferential statistical analyses were performed. RESULTS: In total, 544 parents responded from various cities of Saudi Arabia. Of these, about 75% were males (mean age = 49.9 years) and the majority (~68%) had a university degree and above. In the 6 months preceding the study, 431 respondents had taken their children to physicians. Of these, only 7.2% reported not being prescribed any antibiotics, whereas 66.8% were prescribed an oral antibiotic one or two times and 26% were more than three times. In terms of prescription, 373 respondents (68.6%) purchased antibiotics without a prescription, whereas 171 (31.4%) purchased it only after obtaining a prescription. However, only seven (1.3%) followed instructions regarding antibiotic usage, whereas 50% did not receive any advice from their doctor regarding use. All demographic characteristics, except gender and residence, were found to have significant effect on parents' knowledge on antibiotic use (P < 0.05). CONCLUSION: This study found that in various cities of Saudi Arabia, parents' knowledge, attitudes and practices on antibiotics for their children are poor. These findings highlight the need for parental education programs regarding antibiotic use and for implementing more stringent regulations on antibiotic prescription.

Obesity and childhood asthma in male schoolchildren in Saudi Arabia: Is there a role for leptin, interleukin-4, interleukin-5, and interleukin-21?

BACKGROUND: Adiposity is associated with high serum levels of adipokines and chemokines which are possibly implicated in a co-existence of obesity and asthma. OBJECTIVES: Elucidate the possible roles of leptin, interleukin (IL)-4, IL-5 and IL-21 in linking obesity with childhood asthma. DESIGN: Cross-sectional, analytical. SETTING: Population of schoolchildren in a small Saudi city. SUBJECTS AND METHODS: The study included a representative sample of Saudi schoolchildren grouped as obese asthmatics, non-obese asthmatics, or obese nonasthmatics, with nonobese nonasthmatics as a control group. An asthma control test was done for the asthmatic groups. MAIN OUTCOME MEASURES: Serum levels of leptin, IL-4, IL-5, and IL-21. SAMPLE SIZE: 345 male schoolchildren with a mean (SD) age of 13.0 (2.3) years. RESULTS: Median serum leptin concentrations in obese asthmatics were significantly higher than in nonobese asthmatics ( P<.001). Uncontrolled asthmatics also had significantly higher leptin levels than controlled asthmatic children ( P<.002). Leptin levels were weakly but significantly correlated with the cytokines IL-4, IL-5, and IL-21. CONCLUSIONS: Leptin may contribute to a link between obesity and childhood asthma. Differences in IL-21 levels between nonobese and obese asthmatics suggest that the co-existence of asthma and obesity increased IL-21 levels. Leptin plus some proinflammatory cytokines especially IL-21 may be potential predictors for asthma control in children. LIMITATIONS: Blood sampling at different stages of asthma might influence cytokine expression. CONFLICT OF INTEREST: None.

Effect of melanin on gold nanoparticle-induced hepatotoxicity and lipid peroxidation in rats.

INTRODUCTION: Melanin pigments are produced by melanocytes and are believed to act as antioxidants based on the belief that melanin can suppress electronically stirred states and scavenge the free radicals. MATERIALS AND METHODS: The study was aimed to verify and prove the toxicity induced by administration of gold nanoparticles (GNPs) and to characterize the role of melanin as an antioxidant against inflammatory liver damage, oxidative stress, and lipid peroxidation induced intraperitoneally by GNPs in vivo. RESULTS: The findings from this study confirmed that administration of GNPs intraperitoneally caused liver damage in addition to producing oxidative stress and fatty acid peroxidation. The treatment of rats with melanin along with GNPs induced dramatic changes in all the measured biochemical parameters. Our data demonstrated that melanin completely inhibited inflammatory liver damage, oxidative stress, and lipid peroxidation, which was confirmed by the histological investigation of different liver sections stained by H&E. CONCLUSION: These results suggest the beneficial use of melanin together with GNPs for alleviating its toxicity. Other studies should be implemented taking into consideration the role of melanin in comparison with other natural antioxidants.