First volumetric records of airborne Cladosporium and Alternaria spores in the atmosphere of Al Khor (northern Qatar): a preliminary survey

Aerobiologia - Daily monitoring of airborne fungal spores was carried out for the first time in Al Khor city, Qatar, using a Hirst type 7-day recording volumetric spore trap, from May 2017 to May...     

Effects of Barium Stress in <i>Brassica juncea</i> and <i>Cakile maritima</i>: The Indicator Role of Some Antioxidant Enzymes and Secondary Metabolites

Soil contamination by toxic trace metal elements, like barium (Ba), may stimulate various undesirable changes in the metabolic activity of plants. The plant responses are fast and with, direct or indirect, generation of reactive oxygen species (ROS). To cope with the stress imposed by the ROS production, plants developed a dual cellular system composed of enzymatic and non-enzymatic players that convert ROS, and their by-products, into stable nontoxic molecules. To assess the Ba stress response of two Brassicaceae species (Brassica juncea, a glycophyte, and Cakile maritime, a halophyte), plants were exposure to different Ba concentrations (0, 100, 200, 300 and 500 μM). The plants response was evaluated through their morphology and development, the determination of plant leaves antioxidant enzymatic activities and by the production of plants secondary metabolites. Results indicated that the two Brassicaceae species have the ability to survive in an environment containing Ba (even at 500 μM). The biomass production of C. maritima was slightly affected whereas an increase in biomass B. juncea was noticed. The stress imposed by Ba activated the antioxidant defense system in the two species, noticed by the changes in the leaves activity of catalase (CAT), ascorbate peroxidase (APX) and guaicol peroxidase (GPX), and of the secondary metabolites, through the production of total phenols and flavonoids. The enzymatic response was not similar within the two plant species: CAT and APX seem to have a more important role against the oxidative stress in C. maritima while in B. juncea is GPX. Overall, total phenols and flavonoids production was more significant in the plants aerial part than in the roots, of the both species. Although the two Brassicaceae species response was different, in both plants catalytic and non-catalytic transformation of ROS occurs, and both were able to overcome the Ba toxicity and prevent the cell damage.     

Human ability to detect kinship in strangers' faces: effects of the degree of relatedness

The resemblance between human faces has been shown to be a possible cue in recognizing the relatedness between parents and children, and more recently, between siblings. However, the general inclusive fitness theory proposes that kin-selective behaviours are also relevant to more distant relatives, which requires the detection of larger kinship bonds. We conducted an experiment to explore the use of facial clues by ‘strangers’, i.e. evaluators from a different family, to associate humans of varying degrees of relatedness. We hypothesized that the visual capacity to detect relatedness should be weaker with lower degrees of relatedness. We showed that human adults are capable of (although not very efficient at) assessing the relatedness of unrelated individuals from photographs and that visible facial cues vary according to the degree of relatedness. This sensitivity exists even for kin pair members that are more than a generation apart and have never lived together. Collectively, our findings are in agreement with emerging knowledge on the role played by facial resemblance as a kinship cue. But we have progressed further to show how the capacity to distinguish between related and non-related pairs applies to situations relevant to indirect fitness.     

Circadian Time‐Effect of Orally Administered Loratadine on Plasma Pharmacokinetics in Mice

Little is known about the chronopharmacokinetics of loratadine, a long‐acting tricyclic antihistamine H₁ widely used in the treatment of allergic diseases. Hence, the pharmacokinetics of loratadine and its major metabolite, desloratadine, were investigated after a 20 mg/kg dose of loratadine had been orally administered to comparable groups of mice (n=33), synchronized for three weeks to 12 h light (rest span)/12 h dark (activity span). The drug was administered at three different circadian times (1, 9, and 17 h after light onset [HALO]). Multiple blood samples were collected over 48 h, and plasma concentrations of loratadine and desloratadine were determined by high performance liquid chromatography. There were no significant differences in T_max of loratadine and desloratadine between treatment‐time different groups. However, the elimination half‐life (t1/2) of the parent compound and its metabolite was significantly longer (p<0.01) following administration at 9 HALO (t1/2 loratadine and desloratadine 5.62 and 4.08 h at 9 HALO vs. 4.29 and 2.6 h at 17 HALO vs. 3.26 and 3.27 at 1 HALO). There were relevant (p<0.05) differences in C_max between the three treated groups for loratadine and desloratadine; 133.05±3.55 and 258.07±14.45 ng/mL at 9 HALO vs. 104.5±2.61 and 188.62±7.20 ng/mL at 1 HALO vs. 94.33±20 and 187.75±10.79 ng/mL at 17 HALO. Drug dosing at 17 HALO resulted in highest loratadine and desloratadine total apparent clearance values: 61.46 and 15.97 L/h/kg, respectively, whereas loratadine and desloratadine clearances (CL) were significantly slower (p<0.05) at the other administration times (loratadine and desloratadine CL was 57.3 and 14.22 L/h/kg at 1 HALO vs. 43.79 and 12.89 L/h/kg at 9 HALO, respectively). The area under the concentration‐time curve (AUC) of loratadine and desloratadine was significantly (p<0.05) greater following drug administration at 9 HALO (456.75 and 1550.57 (ng/mL) · h, respectively); it was lowest following treatment at 17 HALO (325.39 and 1252.53 (ng/mL) · h, respectively). These pharmacokinetic data indicate that the administration time of loratadine significantly affected its pharmacokinetics: the elimination of loratadine and its major metabolite desloratadine.     

Proteomics of Breast Muscle Tissue Associated with the Phenotypic Expression of Feed Efficiency within a Pedigree Male Broiler Line: I. Highlight on Mitochondria

As feed represents 60 to 70% of the cost of raising an animal to market weight, feed efficiency (the amount of dry weight intake to amount of wet weight gain) remains an important genetic trait in animal agriculture. To gain greater understanding of cellular mechanisms of feed efficiency (FE), shotgun proteomics was conducted using in-gel trypsin digestion and tandem mass spectrometry on breast muscle samples obtained from pedigree male (PedM) broilers exhibiting high feed efficiency (FE) or low FE phenotypes (n = 4 per group). The high FE group had greater body weight gain (P = 0.004) but consumed the same amount of feed (P = 0.30) from 6 to 7 wk resulting in higher FE (P < 0.001). Over 1800 proteins were identified, of which 152 were different (P < 0.05) by at least 1.3 fold and ≤ 15 fold between the high and low FE phenotypes. Data were analyzed for a modified differential expression (DE) metric (Phenotypic Impact Factors or PIF) and interpretation of protein expression data facilitated using the Ingenuity Pathway Analysis (IPA) program. In the entire data set, 228 mitochondrial proteins were identified whose collective expression indicates a higher mitochondrial expression in the high FE phenotype (binomial probability P < 0.00001). Within the top up and down 5% PIF molecules in the dataset, there were 15 mitoproteome proteins up-regulated and only 5 down-regulated in the high FE phenotype. Pathway enrichment analysis also identified mitochondrial dysfunction and oxidative phosphorylation as the number 1 and 5 differentially expressed canonical pathways (up-regulated in high FE) in the proteomic dataset. Upstream analysis (based on DE of downstream molecules) predicted that insulin receptor, insulin like growth receptor 1, nuclear factor, erythroid 2-like 2, AMP activated protein kinase (α subunit), progesterone and triiodothyronine would be activated in the high FE phenotype whereas rapamycin independent companion of target of rapamycin, mitogen activated protein kinase 4, and serum response factor would be inhibited in the high FE phenotype. The results provide additional insight into the fundamental molecular landscape of feed efficiency in breast muscle of broilers as well as further support for a role of mitochondria in the phenotypic expression of FE.Funding provided by USDA-NIFA (#2013–01953), Arkansas Biosciences Institute (Little Rock, AR), McMaster Fellowship (AUS to WB) and the Agricultural Experiment Station (Univ. of Arkansas, Fayetteville).     

High Prevalence of Methanobrevibacter smithii and Methanosphaera stadtmanae Detected in the Human Gut Using an Improved DNA Detection Protocol

Background

The low and variable prevalence of Methanobrevibacter smithii and Methanosphaera stadtmanae DNA in human stool contrasts with the paramount role of these methanogenic Archaea in digestion processes. We hypothesized that this contrast is a consequence of the inefficiencies of current protocols for archaeon DNA extraction. We developed a new protocol for the extraction and PCR-based detection of M. smithii and M. stadtmanae DNA in human stool.

Methodology/Principal Findings

Stool specimens collected from 700 individuals were filtered, mechanically lysed twice, and incubated overnight with proteinase K prior to DNA extraction using a commercial DNA extraction kit. Total DNA was used as a template for quantitative real-time PCR targeting M. smithii and M. stadtmanae 16S rRNA and rpoB genes. Amplification of 16S rRNA and rpoB yielded positive detection of M. smithii in 95.7% and M. stadtmanae in 29.4% of specimens. Sequencing of 16S rRNA gene PCR products from 30 randomly selected specimens (15 for M. smithii and 15 for M. stadtmanae) yielded a sequence similarity of 99–100% using the reference M. smithii ATCC 35061 and M. stadtmanae DSM 3091 sequences.

Conclusions/Significance

In contrast to previous reports, these data indicate a high prevalence of the methanogens M. smithii and M. stadtmanae in the human gut, with the former being an almost ubiquitous inhabitant of the intestinal microbiome.     

Hyperglycaemia, stress oxidant, liver dysfunction and histological changes in diabetic male rat pancreas and liver: protective effect of 17 beta-estradiol

Oxidative stress is thought to play a crucial role in the pathogenesis of chronic diabetic complications. We investigated the protective effects of 17 beta-estradiol (E2) on alloxan-induced stress oxidant, hepatic dysfunction and histological changes in male rats liver and pancreas. Our results showed that 17 beta-estradiol could attenuate the increase of blood glucose in plasma and normalise the hepatic glycogen level. In addition, E2 enhanced superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) (by 207, 52 and 72%, respectively, as compared to diabetic rats), reduced lipid peroxidation in the hepatic tissue (by 54%) and improved the liver dysfunction parameters by the significant decrease of gamma-glytamyl transferase (GGT), phosphatases alkalines (PAL), lactate deshydrogenase (LDH) and aspartate and lactate transaminases (AST and ALT) activities which increased in diabetic rats. Moreover, 17 beta-estradiol treatment in diabetic rats protects against alloxan-induced pancreatic beta-cells and hepatic cells damages.     

Cloning and Sequencing of an Original Gene Encoding a Maltogenic Amylase from <Emphasis Type="Italic">Bacillus</Emphasis> sp. US149 Strain and Characterization of the Recombinant Activity

A gene encoding maltogenic amylase from acidic Bacillus sp. US149 (maUS149) was cloned, sequenced and over-expressed in Escherichia coli. The nucleotide sequence analysis revealed an open reading frame (ORF) of 1749 bp encoding a protein of 582 residues. The alignment of deduced amino acid sequence revealed a relatively low homology with the already reported maltogenic amylases. In fact, its highest identity, of only 60%, was found with the maltogenic amylase of Thermus sp. IM6501. The recombinant enzyme (MAUS149) was found to be intracellular and was purified to homogeneity from the cell crude extract with a yield of 23%. According to PAGE analysis, under reducing and non-reducing conditions, the recombinant enzyme has an apparent molecular weight of 135 kDa and is composed of two identical subunits of 67.5 kDa each. The maximum activity was obtained at 40°C and pH 6.5. MAUS149 could be classified as a maltogenic amylase since it produces mainly maltose from starch, maltose and glucose from β-cyclodextrin, and panose from pullulan.     

Development of a small-scale bioreactor: application to in vivo NMR measurement

A perfused bioreactor allowing in vivo NMR measurement was developed and validated for Eschscholtzia californica cells. The bioreactor was made of a 10-mm NMR tube. NMR measurement of the signal-to-noise ratio was optimized using a sedimented compact bed of cells that were retained in the bioreactor by a supporting filter. Liquid medium flow through the cell bed was characterized from a mass balance on oxygen and a dispersive hydrodynamic model. Cell bed oxygen demand for 4 h perfusion required a minimal medium flow rate of 0.8 mL/min. Residence time distribution assays at 0.8-2.6 mL/min suggest that the cells are subjected to a uniform nutrient environment along the cell bed. Cell integrity was maintained for all culture conditions since the release of intracellular esterases was not significant even after 4 h of perfusion. In vivo NMR was performed for (31)P NMR and the spectrum can be recorded after only 10 min of spectral accumulation (500 scans) with peaks identified as G-6P, F-6P, cytoplasmic Pi, vacuolar Pi, ATP(gamma) and ADP(beta), ATP(alpha) and ADP(alpha), NADP and NDPG, NDPG and ATP(beta). Cell viability was shown to be maintained as (31)P chemical shifts were constant with time for all the identified nuclei, thus suggesting constant intracellular pH.