Mercury (Hg) Exposure in Breast-Fed Infants and Their Mothers and the Evidence of Oxidative Stress

The objective of this work was to assess exposure to mercury (Hg) and its induction of oxidative stress in 155 healthy lactating Saudi mothers and their infants. Samples of breast milk and blood were collected from the mothers, while urine was taken from both infants and mothers. Both urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) were measured in mothers and infants as biomarkers of oxidative stress. The mean concentration of Hg in breast milk was 1.19 μg/L (range 0.012–6.44 μg/L) with only one mother having Hg >4 μg/L, the upper limit established by the US Agency for Toxic Substance and Disease Registry. However, 57.4 % had Hg ≥1 μg/L, the background level for Hg in human milk. The mean urinary Hg corrected for creatinine (Hg-C) in mothers and infants was 1.47 and 7.90 μg/g creatinine, respectively, with a significant correlation between the two (p?<?0.001). Urinary Hg levels over 5 μg/g creatinine (the background level in an unexposed population) were found in 3.3 % of mothers and 50.1 % of infants. None of the mothers had total blood Hg above the US Environmental Protection Agency’s maximum reference dose of 5.8 μg/L. No correlation was noted between urinary Hg in infants and Hg in breast milk (p?>?0.05). Hg in breast milk, though, was associated with Hg in blood (p?<?0.001), suggesting the efficient transfer of Hg from blood to milk. Hg in the breast milk of mothers and in the urine of infants affected the excretion of urinary MDA and 8-OHdG, respectively, in a dose-related manner. These findings reveal for the first time lactational exposure to Hg-induced oxidative stress in breast-fed infants, which may play a role in pathogenesis, particularly during neurodevelopment. This will also contribute to the debate over the benefits of breast milk versus the adverse effects of exposure to pollutants. Nevertheless, breastfeeding should not be discouraged, but efforts should be made to identify and eliminate the source of Hg exposure in the population.     

Comparative phytochemical profiling of different soybean (Glycine max (L.) Merr) genotypes using GC–MS

This study aimed to estimate the proximate, phenolic and flavonoids contents and phytochemicals present in seeds of twenty four soybeans (Glycine max (L.) Merr) genotypes to explore their nutritional and medicinal values. Crude protein composition ranged between 35.63 and 43.13% in Argentinian and USA (Clark) genotypes, respectively. Total phenolic content varied from 1.15 to 1.77?mg?GAE/g, whereas flavonoids varied from 0.68 to 2.13?mg?QE/g. The GC–MS analysis resulted identification of 88 compounds categorized into aldehydes (5), ketones (13), alcohols (5), carboxylic acids (7), esters (13), alkanes (2), heterocyclic compounds (19), phenolic compound (9), sugar moiety (7) ether (4) and amide (3), one Alkene and one fatty acid ester. Indonesian genotypes (Ijen and Indo-1) had the highest phenolic compounds than others genotype having antioxidant activities, while the Australian genotype contains the maximum in esters compounds. The major phytocompounds identified in majority of genotypes were Phenol, 2,6-dimethoxy-, 2-Methoxy-4-vinylphenol, 3,5-Dimethoxyacetophenone, 1,2-cyclopentanedione and Hexadecanoic acid, methyl ester. The presence of phytochemicals with strong pharmacological actions like antimicrobial and antioxidants activities could be considered as sources of quality raw materials for food and pharmaceutical industries. This study further set a platform for isolating and understanding the characteristics of each compound for it pharmacological properties.     

Countrywide Survey for MERS-Coronavirus Antibodies in Dromedaries and Humans in Pakistan

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic pathogen capable of causing severe respiratory disease in humans. Although dromedary camels are considered as a major reservoir host, the MERS-CoV infection dynamics in camels are not fully understood. Through surveillance in Pakistan, nasal (n = 776) and serum (n = 1050)samples were collected from camels between November 2015 and February 2018. Samples were collected from animal markets, free-roaming herds and abattoirs. An in-house ELISA was developed to detect IgG against MERS-CoV. A total of 794 camels were found seropositive for MERS-CoV. Prevalence increased with the age and the highest seroprevalence was recorded in camels aged [ 10 years (81.37%) followed by those aged 3.1–10 years (78.65%) and B 3 years (58.19%).Higher prevalence was observed in female (78.13%) as compared to male (70.70%). Of the camel nasal swabs, 22 were found to be positive by RT-qPCR though with high Ct values. Moreover, 2,409 human serum samples were also collected from four provinces of Pakistan during 2016–2017. Among the sampled population, 840 humans were camel herders.Although we found a high rate of MERS-CoV antibody positive dromedaries (75.62%) in Pakistan, no neutralizing antibodies were detected in humans with and without contact to camels.     

Characterization of Maize Iranian Mosaic Virus and Comparison with Hawaiian and Other Isolates of Maize Mosaic Virus (Rhabdoviridae)

Maize Iranian mosaic virus (MIMV) was characterized and compared with isolates of Maize mosaic virus (MMV, genus Nucleorhabdovirus, family Rhabdoviridae) in insect transmission, cytopathology and ultrastructure of infected maize cells, virion proteins and serologically. MIMV is naturally transmitted by Ribautodelphax notabilis, a delphacid planthopper, in Iran. In this study, another planthopper, Peregrinus maidis, vector of MMV, transmitted MIMV with an estimated efficiency of 0.4–1.6% following feeding on MIMV‐infected maize plants and 64% following injection of MIMV into the hemolymph, suggesting that P. maidis gut tissues largely blocked MIMV transmission. MIMV and MMV‐HI (Hawaii) induced similar cytopathologies in cells of infected maize leaves, with virions budding through inner nuclear and endoplasmic reticulum membranes. In thin sections, virions of MIMV were significantly shorter than those of MMV‐HI. Sodium dodecyl sulphate polyacrylamide gel electrophoresis analysis of virions of MIMV, MMV‐HI, MMV‐CR (Costa Rica) and MMV‐FL (Florida) yielded six proteins of which four were identified as the putative G, N, P and M proteins of plant rhabdoviruses. The N, P and M proteins of MIMV migrated faster in gels than those of the MMV isolates indicating a lower molecular weight, whereas the bands corresponding to the G proteins migrated similarly for both viruses. Polyclonal antibodies to MMV‐HI failed to react with virions of MIMV in enzyme‐linked immunosorbent assay (ELISA) and with MIMV proteins in Western blots. In contrast, these antibodies reacted strongly with MMV‐HI and MMV‐FL virions in ELISA and with MMV‐HI, MMV‐CR and MMV‐FL proteins in Western blots. Further, in ELISA, polyclonal antibodies to MMV‐MR (Mauritius) reacted weakly with MIMV virions but strongly with MMV‐HI and MMV‐FL virions. Thus, it is concluded that MIMV is a new virus of the Nucleorhabdovirus genus that may be distantly related to MMV.     

Clinical,Molecular, and Computational Analysis in two cases with mitochondrial encephalomyopathy associated with SUCLG1 mutation in a consanguineous family

Deficiency of the mitochondrial enzyme succinyl COA ligase (SUCL) is associated with encephalomyopathic mtDNA depletion syndrome and methylmalonic aciduria. This disorder is caused by mutations in both SUCL subunits genes: SUCLG1 (α subnit) and SUCLA2 (β subnit). We report here, two Tunisian patients belonging to a consanguineous family with mitochondrial encephalomyopathy, hearing loss, lactic acidosis, hypotonia, psychomotor retardation and methylmalonic aciduria. Mutational analysis of SUCLG1 gene showed, for the first time, the presence of c.41T > C in the exon 1 at homozygous state. In-silico analysis revealed that this mutation substitutes a conserved methionine residue to a threonine at position 14 (p.M14T) located at the SUCLG1 protein mitochondrial targeting sequence. Moreover, these analysis predicted that this mutation alter stability structure and mitochondrial translocation of the protein. In Addition, a decrease in mtDNA copy number was revealed by real time PCR in the peripheral blood leukocytes in the two patients compared with controls.     

The effect of a daytime 60-min nap opportunity on postural control in highly active individuals

Although napping is commonly used as a strategy to improve numerous physical and cognitive performances, the efficacy of this strategy for improving postural balance has not yet been elucidated. Thus, the aim of this study was to conduct a comprehensive examination of the effect of a 60 min nap opportunity (N60) on different components of postural control. Ten highly active individuals (age = 27 ± 3.5 y, height = 1.75 ± 0.52 m, weight = 66.02 ± 8.63 kg) performed, in a randomized order, two afternoon test sessions following no nap (NN) and N60. Postural balance was assessed using the sensory organisation test (SOT), the unilateral stance test (UST), and the limits of Stability Test performed on NeuroCom^® Smart Balance Master. The subjective rating of sleepiness before and after the nap conditions was also assessed. Compared to NN, N60 improved the composite balance score (p < 0.05, ES = 0.75, Δ = 5.3%) and the average and maximum percentage balance in the most challenging postural conditions of the SOT (p < 0.05 for SOT-4 and 5 and p < 0.0005 for SOT-6; ES range between 0.58 and 1.1). This enhanced postural balance in N60 was accompanied with improved visual (p < 0.05; ES = 0.93; Δ = 8.9%) and vestibular (p < 0.05; ES = 0.81; Δ = 10.5%) ratios and a reduced level of sleepiness perception (p < 0.001, ES = 0.87). However, no significant differences were found in any of the UST and LOS components’ scores (p > 0.05). Overall, a 60 min post lunch nap opportunity may be viable for improving static balance, although further work, involving larger samples and more complex motor activities, is warranted.     

Nanostructured lipid carriers as semisolid topical delivery formulations for diflucortolone valerate

Context: Topical treatment of skin disease needs to be strategic to ensure high drug concentration in the skin with minimum systemic absorption.

Objective: The aim of this study was to produce semisolid nanostructured lipid carrier (NLC) formulations, for topical delivery of the corticosteroid drug, diflucortolone valerate (DFV), with minimum systemic absorption.

Method: NLC formulations were developed using a high shear homogenization combined with sonication, using Precirol® ATO5 or Tristearin® as the solid lipid, Capryol? or isopropyl myristate as the liquid lipid and Poloxamer® 407 as surfactant. The present study addresses the influence of different formulations composition as solid lipid, liquid lipid types and concentrations on the physicochemical properties and drug release profile from NLCs.

Results and discussion: DFV-loaded NLC formulations possessed average particle size ranging from 160.40?nm to 743.7?nm with narrow polydispersity index. The encapsulation efficiency was improved by adding the lipid-based surfactants (Labrasol® and Labrafil® M1944CS) to reach 68%. The drug release from the investigated NLC formulations showed a prolonged release up to 12?h. The dermatopharmacokinetic study revealed an improvement in drug deposition in the skin with the optimized DFV-loaded NLC formulation, in contrast to a commercial formulation.

Conclusion: NLC provides a promising nanocarrier system that work as reservoir for targeting topical delivery of DFV.     

Quantitative trait loci for resistance to stripe rust of wheat revealed using global field nurseries and opportunities for stacking resistance genes

Key message

Quantitative trait loci controlling stripe rust resistance were identified in adapted Canadian spring wheat cultivars providing opportunity for breeders to stack loci using marker-assisted breeding.

Abstract

Stripe rust or yellow rust, caused by Puccinia striiformis Westend. f. sp. tritici Erikss., is a devastating disease of common wheat (Triticum aestivum L.) in many regions of the world. The objectives of this research were to identify and map quantitative trait loci (QTL) associated with stripe rust resistance in adapted Canadian spring wheat cultivars that are effective globally, and investigate opportunities for stacking resistance. Doubled haploid (DH) populations from the crosses Vesper/Lillian, Vesper/Stettler, Carberry/Vesper, Stettler/Red Fife and Carberry/AC Cadillac were phenotyped for stripe rust severity and infection response in field nurseries in Canada (Lethbridge and Swift Current), New Zealand (Lincoln), Mexico (Toluca) and Kenya (Njoro), and genotyped with SNP markers. Six QTL for stripe rust resistance in the population of Vesper/Lillian, five in Vesper/Stettler, seven in Stettler/Red Fife, four in Carberry/Vesper and nine in Carberry/AC Cadillac were identified. Lillian contributed stripe rust resistance QTL on chromosomes 4B, 5A, 6B and 7D, AC Cadillac on 2A, 2B, 3B and 5B, Carberry on 1A, 1B, 4A, 4B, 7A and 7D, Stettler on 1A, 2A, 3D, 4A, 5B and 6A, Red Fife on 2D, 3B and 4B, and Vesper on 1B, 2B and 7A. QTL on 1A, 1B, 2A, 2B, 3B, 4A, 4B, 5B, 7A and 7D were observed in multiple parents. The populations are compelling sources of recombination of many stripe rust resistance QTL for stacking disease resistance. Gene pyramiding should be possible with little chance of linkage drag of detrimental genes as the source parents were mostly adapted cultivars widely grown in Canada.

     

Diagnostic dilemma of cardiac syncope in pediatric patients

Aims

Syncope is defined as temporary loss of consciousness and postural tone resulting from an abrupt transient decrease in cerebral blood flow. The present work aimed at determining how diagnostic tests are used in the evaluation of pediatric syncope at a tertiary pediatric referral center and to report on the utility and the yield of these tests.

Settings and Design

Retrospective study conducted at a tertiary referral arrhythmolology service

Methods and Material

The clinical charts of 234 pediatric patients presenting with a primary complaint of syncope with an average age of 7.48 ± 3.82(3.5-16) years were reviewed by the investigators.

Statistical analysis used

Statistical Package of social science (SPSS) version 9,0 was used for analysis of data.

Results

The commonest trigger for syncope in the study population was early following exercise (n=65) and the commonest prodrome was palpitation, noted in 25 patients. A murmur was present in 19 of our patients (8.3%) while 10.7% (n=25) had abnormal ECGs. Of the 106 echocardiograms done, 14 (13.2%) were abnormal. Only two of them were missed by ECG. All patients were offered ambulatory 24 hour ECG. One patient with sick sinus syndrome was diagnosed only with Holter.

Conclusions

Clues to the presence of cardiac syncope may include acute onset of syncope, frequent episodes, low difference between blood pressure readings in supine and erect positions (after standing for 2 minutes) and most importantly an abnormal 12 lead ECG. Transthoracic echo and Holter monitoring have low yield in pediatric syncope.