Silver Nanoparticles for the Adsorption of Manganese from Biological Samples

In this study, silver nanoparticles were prepared and used for separation and preconcentration of manganese from biological samples. The technical feasibility of silver nanoparticles for manganese removal was investigated under batch studies. The effects of different parameters such as pH of solution, time (t), amounts of PAN (E), and silver nanoparticles (N) on the adsorption of manganese by silver nanoparticle were investigated using factorial design and response surface methodology based on Box–Behnken design. Thermodynamic parameters indicate the adsorption process to be exothermic. The limit of detection of the proposed method followed by inductively coupled plasma was found to be 0.08?µg L^?1. The method was applied to determine of manganese in biological samples.     

Potential lactoferrin activity against pathogenic viruses

Lactoferrin (LF) is an 80-kDa globular glycoprotein with high affinity for metal ions, particularly for iron. This protein possesses many biological functions, including the binding and release of iron and serves as one of the important components of the innate immune system, where it acts as a potent inhibitor of several pathogens. LF has efficacious antibacterial and antiviral activities against a wide range of Gram-positive and Gram-negative bacteria and against both naked and enveloped DNA and RNA viruses. In its antiviral pursuit, LF acts predominantly at the acute phase of the viral infection or even at the intracellular stage, as in hepatitis C virus infection. LF inhibits the entry of viral particles into host cells, either by direct attachment to the viral particles or by blocking their cellular receptors. This wide range of activities may be attributed to the capacity of LF to bind iron and its ability to interfere with the cellular receptors of both hosts and pathogenic microbes.     

Insecticides and soil microorganisms. III. Fate of 14C-labelled Dipterex as affected by two nodule-forming rhizobium spp. and roots of their respective leguminous host plants.

Chromatographic analysis led to the identification of monomethyl- and dimethyl-phosphates as metabolites resulting from the enzymatic degradation of 14C-labelled Dipterex in the buffer solutions and root tissues of broad bean and clover plants, as well as in the culture media of rhizobium leguminosarum and Rhizobium trifolii. The formation of 14CO2 from rhizobial cultures containing radioactive Dipterex suggests that some of the liberated methanol groups (during breakdown of Dipterex) are oxidatively degraded by the two Rhizobium spp.     

An innovative lattice Boltzmann model for simulating Michaelis–Menten-based diffusion–advection kinetics and its application within a cartilage cell bioreactor

Lattice Boltzmann models (LBM) are rapidly showing their ability to simulate a lot of fluid dynamics problems that previously required very complex approaches. This study presents a LBM for simulating diffusion–advection transport of substrate in a 2-D laminar flow. The model considers the substrate influx into a set of active cells placed inside the flow field. A new innovative method was used to simulate the cells activity using the LBM by means of Michaelis–Menten kinetics. The model is validated with some numerical benchmark problems and proved highly accurate results. After validation the model was used to simulate the transport of oxygen substrates that diffuse in water to feed a set of active cartilage cells inside a new designed bioreactor.     

Two novel loci underlie natural differences in Caenorhabditis elegans abamectin responses

Parasitic nematodes cause a massive worldwide burden on human health along with a loss of livestock and agriculture productivity. Anthelmintics have been widely successful in treating parasitic nematodes. However, resistance is increasing, and little is known about the molecular and genetic causes of resistance for most of these drugs. The free-living roundworm Caenorhabditis elegans provides a tractable model to identify genes that underlie resistance. Unlike parasitic nematodes, C. elegans is easy to maintain in the laboratory, has a complete and well annotated genome, and has many genetic tools. Using a combination of wild isolates and a panel of recombinant inbred lines constructed from crosses of two genetically and phenotypically divergent strains, we identified three genomic regions on chromosome V that underlie natural differences in response to the macrocyclic lactone (ML) abamectin. One locus was identified previously and encodes an alpha subunit of a glutamate-gated chloride channel (glc-1). Here, we validate and narrow two novel loci using near-isogenic lines. Additionally, we generate a list of prioritized candidate genes identified in C. elegans and in the parasite Haemonchus contortus by comparison of ML resistance loci. These genes could represent previously unidentified resistance genes shared across nematode species and should be evaluated in the future. Our work highlights the advantages of using C. elegans as a model to better understand ML resistance in parasitic nematodes.     

A novel regulatory role of TRAPPC9 in L-plastin-mediated osteoclast actin ring formation

Trafficking protein particle complex 9 (TRAPPC9) is a major subunit of the TRAPPII complex. TRAPPC9 has been reported to bind nuclear factor κB kinase subunit β (IKKβ) and NF-kB-inducing kinase (NIK) where it plays a role in the canonical and noncanonical of nuclear factor-κB (NF-kB) signaling pathways, receptively. The role of TRAPPC9 in protein trafficking and cytoskeleton organization in osteoclast (OC) has not been studied yet. In this study, we examined the mRNA expression of TRAPPC9 during OC differentiation. Next, we examined the colocalization of TRAPPC9 with cathepsin-K, known to mediate OC resorption suggesting that TRAPPC9 mediates the trafficking pathway within OC. To identify TRAPPC9 protein partners important for OC-mediated cytoskeleton re-organization, we conducted immunoprecipitation of TRAPPC9 in mature OCs followed by mass spectrometry analysis. Our data showed that TRAPPC9 binds various protein partners. One protein with high recovery rate is L-plastin (LPL). LPL localizes at the podosomes and reported to play a crucial role in actin aggregation thereby actin ring formation and OC function. Although the role of LPL in OC-mediated bone resorption has not fully reported in detail. Here, first, we confirmed the binding of LPL to TRAPPC9 and, then, we investigated the potential regulatory role of TRAPPC9 in LPL-mediated OC cytoskeleton reorganization. We assessed the localization of TRAPPC9 and LPL in OC and found that TRAPPC9 is colocalized with LPL at the periphery of OC. Next, we determined the effect of TRAPPC9 overexpression on LPL recruitment to the actin ring using a viral system. Interestingly, our data showed that TRAPPC9 overexpression promotes the recruitment of LPL to the actin ring when compared with control cultures. In addition, we observed that TRAPPC9 overexpression reorganizes actin clusters/aggregates and regulates vinculin recruitment into the OC periphery to initiate podosome formation.     

Contribution of the mesophilic fungi of different spices in Egypt

Thirty-eight genera and 81 species of fungi were isolated and identified from 120 samples of 24 kinds of spices collected from different places at Assiut Governorate, Egypt. Predominant genera wereAspergillus (25 species) andPenicillium (7 species) of whichA. flavus, A. niger, A. ochraceus, A. fumigatus, A. flavus var.columnaris, A. terreus, P. chrysogenum andP. corylophilum were the most commonly occurring.     

Suitability of different mite prey for the development of the predatory mite,Phytoseiulus persimilis

Development of the phytoseiid mitePhytoseiulus persimilis Athias-Henriot was studied when fed on three mite species as prey. The tenuipalpid mite,Brevipalpus pulcher (Canestrini & Fanzago), is an unsuitable prey forP. persimilis as predatory larvae reared on any stages developed to the protonymphal stage only. WhenP. persimilis larvae were reared on the eriophyid mite,Eriophyes dioscoridis Soliman & Abou-Awad, only a few developed to adulthood, but failed to oviposit. On the contrary, predatory larvae fed on the tetranychid mite,Tetranychus urticae Koch, matured in a significantly shorter period and resulting females exhibited a high rate of reproduction.     

Conjugative transfer functions of broad-host-range plasmid RK2 are coregulated with vegetative replication

The kilB locus (which is unclonable in the absence of korB) of broad-host-range plasmid RK2 (60 kb) lies between the trfA operon (co-ordinates 16.4 to 18.2 kb), which encodes a protein essential for vegetative replication, and the Tra2 block of conjugative transfer genes (co-ordinates 20.0 to 27.0 kb). Promoter probe studies indicated that kilB is transcribed clockwise from a region containing closely spaced divergent promoters, one of which is the trfA promoter. The repression of both promoters by korB suggested that kilB may also play a role in stable maintenance of RK2. We have sequenced the region containing kilB and analysed it by deletion and insertion mutagenesis. Loss of the KilB+ phenotype does not result in decreased stability of mini RK2 plasmids. However insertion in ORFI (kilBI) of the region analysed results in a Tra- phenotype in plasmids which are otherwise competent for transfer, demonstrating that this locus is essential for transfer and is probably the first gene of the Tra2 region. From the kilBI DNA sequence KilBI is predicted to be 34995 Da, in line with M(r) = 36,000 observed by sodium dodecyl sulphate/polyacrylamide gel electrophoresis, and contains a type I ATP-binding motif. The purified product was used to raise antibody which allowed the level of KilBI produced from RK2 to be estimated at approximately 2000 molecules per bacterium. Protein sequence comparisons showed the highest homology score with VirB11, which is essential for the transfer of the Agrobacterium tumefaciens Ti plasmid DNA from bacteria to plant cells. The sequence similarity of both KilBI and VirB11 to a family of protein export functions suggested that KilBI may be involved in assembly of the surface-associated Tra functions. The data presented in this paper provide the first demonstration of coregulation of genes required for vegetative replication and conjugative transfer on a bacterial plasmid.