Identification of the amino acids in the Major Histocompatibility Complex class II region of Scottish Blackface sheep that are associated with resistance to nematode infection

Lambs with the Major Histocompatibility Complex DRB1*1101 allele have been shown to produce fewer nematode eggs following natural and deliberate infection. These sheep also possess fewer adult Teladorsagia circumcincta than sheep with alternative alleles at the DRB1 locus. However, it is unclear if this allele is responsible for the reduced egg counts or merely acts as a marker for a linked gene. This study defined the MHC haplotypes in a population of naturally infected Scottish Blackface sheep by PCR amplification and sequencing, and examined the associations between MHC haplotypes and faecal egg counts by generalised linear mixed modelling. The DRB1*1101 allele occurred predominately on one haplotype and a comparison of haplotypes indicated that the causal mutation or mutations occurred in or around this locus. Additional comparisons with another resistant haplotype indicated that mutations in or around the DQB2*GU191460 allele were also responsible for resistance to nematode infections. Further analyses identified six amino acid substitutions in the antigen binding site of DRB1*1101 that were significantly associated with reductions in the numbers of adult T. circumcincta.     

Otomycosis in the South of Iran with a High Prevalence of Tympanic Membrane Perforation: A Hospital-Based Study

Mycopathologia - Otomycosis is a superficial infection of the external ear caused by fungal pathogens. The genera Aspergillus and Candida are considered the main fungal causative agents, with the...     

Influence of meteorological parameters and PM2.5 on the level of culturable airborne bacteria and fungi in Abadan,Iran

In recent years, monitoring of airborne bacteria and fungi concentrations has obtained increasing universal attraction not only for influences on ecological balance but also for evaluating their public health consequences. In this study, we aimed to investigate culturable airborne bacteria and fungi levels in different sites of Abadan, and their association with meteorological parameters and PM_2.5 levels. Abadan is one of the most industrialized cities in the southwest of Iran where over the current decade has experienced lots of dust storm episodes. In total, 400 air samples were collected in 6 months (autumn and winter) using a single-stage viable Andersen cascade impactor for sampling airborne bacteria and fungi and portable DustTrak Aerosol Monitor 8520 for measuring PM_2.5 concentrations and meteorological parameters. Microbial concentrations showed a significant difference between various sites over the study period with averages of 569.57?±?312.64 and 482.73?±?242.86 CFU/M³ for bacteria and fungi, respectively. The air temperature had a significant effect on the concentration of both airborne bacteria and fungi. A significant positive correlation between relative humidity and fungi but no correlation between relative humidity and bacteria concentrations were observed. The average airborne PM_2.5 concentrations of all sites among the study period was 93.24?±?116.72 μg/m³. The atmospheric bacterial and fungal communities were strongly positively correlated with the ambient PM_2.5 level. The levels of airborne bacteria and fungi along with PM_2.5 in the air of the city were relatively higher than the recommended levels. Therefore, the best course of action is needed to control emission sources. Further studies are also needed to evaluate the clinical analysis of the health effects of exposure to these pollutants.

     

In silico analysis and modeling of ACP-MIP–PilQ chimeric antigen from Neisseria meningitidis serogroup B

Background:

Neisseria meningitidis, a life-threatening human pathogen with the potential to cause large epidemics, can be isolated from the nasopharynx of 5–15% of adults. The aim of the current study was to evaluate biophysical and biochemical properties and immunological aspects of chimeric acyl-carrier protein-macrophage infectivity potentiator protein-type IV pilus biogenesis protein antigen (ACP-MIP-PilQ) from N. meningitidis serogroup B strain.

Methods:

Biochemical properties and multiple alignments were predicted by appropriate web servers. Secondary molecular structures were predicted based on Chou and Fasman, Garnier-Osguthorpe-Robson, and Neural Network methods. Tertiary modeling elucidated conformational properties of the chimeric protein. Proteasome cleavage and transporter associated with antigen processing (TAP) binding sites, and T- and B-cell antigenic epitopes, were predicted using bioinformatic web servers.

Results:

Based on our in silico and immunoinformatics analyses, the ACP-MIP-PilQ protein (AMP) can induce high-level cross-strain bactericidal activity. In addition, several immune proteasomal cleavage sites were detected. The 22 epitopes associated with MHC class I and class II (DR) alleles were confirmed in the AMP. Thirty linear B-cell epitopes as antigenic regions were predicted from the full-length protein.

Conclusion:

All predicted properties of the AMP indicate it could be a good candidate for further immunological in vitro and in vivo studies.Key Words: Chimeric protein, In silico, Neisseria meningitides, serogroup B, Vaccine     

Compatibility and interaction between Bacillus thuringiensis and certain insecticides: perspective in management of Tuta absoluta (Lepidoptera: Gelechiidae)

Bacillus thuringiensis var. kurstaki (Berliner) (Bt) has been suggested as a biological control agent for Tuta absoluta (Meyrick). The objective of this study was to determine the interaction between abamectin, azadirachtin, indoxacarb, chlorantraniliprole, dichlorvos and metaflumizone with Bt. Effect of recommended doses of the chemical insecticides on colonisation of Bt was also investigated in culture medium. Except for metaflumizone, none of the chemicals tested reduced the colonisation of Bt compared with control. Interaction between Bt and the chemical insecticides on 2nd-instar larvae was also assessed. In interaction tests, Bt was applied at LC₅₀ level, 0, 12, 24 or 36 h after treating the larvae with LC₁₀ or LC₂₅ of the chemical insecticides. An antagonistic effect was observed in all treatments where Bt was applied immediately after the chemical insecticide. Also, antagonism was observed when treatment with Bt was done 12 h after azadirachtin and metaflumizone applications. Applying Bt 12 and 24 h after treatment with LC₂₅ of chlorantraniliprole, dichlorvos and abamectin resulted in synergism. But, synergism with LC₁₀ of dichlorvos and abamectin was observed only after 12 h. Additive effect was observed in the rest of the time and concentration combinations. Based on the results obtained, simultaneous use of the chemical insecticides tested and Bt is not recommended for T. absoluta control; and an appropriate time interval should be taken into consideration accordingly.     

A gas phase chromatography method for determination of low dissolved CO2 concentration and/or CO2 solubility in microbial culture media

CO₂ concentration in aqueous samples was derived from determination of the CO₂ content in the gas phase at equilibrium with the liquid by gas chromatography. This technique was used to measure low dissolved CO₂ concentrations, down to 10^–6 mol/L, and CO₂ solubility in microbial culture media. The method gave results with an accuracy within 10%, and appeared thus as reliable and sensitive. It could be considered as a valuable tool to study CO₂ mass transfer in bio-processes.     

A novel mass spectrometric approach to the analysis of hormonal peptides in extracts of mouse pancreatic islets.

Liquid chromatography mass spectrometry (LC-MS) is a valuable tool in the analysis of proteins and peptides. The combination of LC-MS with different fragmentation methods provides sequence information on components in complex mixtures. In this work, on-line packed capillary LC electrospray ionization Fourier transform ion cyclotron resonance MS was combined with two complementary fragmentation techniques, i.e. nozzle-skimmer fragmentation and electron capture dissociation, for the determination of hormonal peptides in an acid ethanol extract of mouse pancreatic islets. The most abundant peptides, those derived from proinsulin and proglucagon, were identified by their masses and additional sequence-tag information established their identities. Interestingly, the experiments demonstrated the presence of truncated C-peptides, des-(25-29)-C-peptide and des-(27-31)-C-peptide. These novel findings clearly illustrate the potential usefulness of the described technique for on-line sequencing and characterization of peptides in tissue extracts.     

Melatonin and TiO2 NPs Application-Induced Changes in Growth,Photosynthesis, Antioxidant Enzymes Activities and Secondary Metabolites in Stevia (Stevia rebaudiana Bertoni) Under Drought Stress Conditions

Journal of Plant Growth Regulation - Drought stress is one of the major constraints on the growth and productivity of crop plants. Recently, new approaches have been employed in order to cope with...     

Novel spiro[indene-1,2′-quinazolin]-4′(3′H)-one derivatives as potent anticonvulsant agents: One-pot synthesis,in vivo biological evaluation,and molecular docking studies

A new series of spiro[indene-1,2′-quinazolin]-4′(3′H)-one derivatives 4a–m were synthesized via a one-pot method and evaluated for anticonvulsant activities using pentylenetetrazole (PTZ) and maximal electroshock (MES)-induced seizures. Obtained results demonstrated that these compounds have not anticonvulsant activity in PTZ test while are active in the MES test. Among the synthesized compounds, the best anticonvulsant activity was obtained with compound 4h . This compound also was not neurotoxic. Given that the title new compounds have the pharmacophore requirement for benzodiazepine (BZD) receptor agonist, the most potent compound was assayed in vivo and in silico as BZD receptor agonist. After treatment with flumazenil as a standard BZD receptor antagonist, anticonvulsant activity of compound 4h decreased. Therefore, the involvement of BZD receptors in anticonvulsant activity of this compound confirmed. Furthermore, docking study of compound 4h in the BZD-binding site of GABA_A receptor confirmed that this compound interacted with the important residues.