SUMMARY Several benzoylphenyl urea-derived insecticides such as diflubenzuron (DFB, Dimilin®) are in wide use to control various insect pests. Although this class of compounds is known to disrupt molting and to affect chitin content, their precise mode of action is still not understood. To gain a broader insight into the mechanism underlying the insecticidal effects of benzoylphenyl urea compounds, we conducted a comprehensive study with the model beetle species and stored product pest Tribolium castaneum (red flour beetle) utilizing genomic and proteomic approaches. DFB was added to a wheat flour-based diet at various concentrations and fed to larvae and adults. We observed abortive molting, hatching defects and reduced chitin amounts in the larval cuticle, the peritrophic matrix and eggs. Electron microscopic examination of the larval cuticle revealed major structural changes and a loss of lamellate structure of the procuticle. We used a genomic tiling array for determining relative expression levels of about 11,000 genes predicted by the GLEAN algorithm. About 6% of all predicted genes were more than 2-fold up-or down-regulated in response to DFB treatment. Genes encoding enzymes involved in chitin metabolism were unexpectedly unaffected, but many genes encoding cuticle proteins were affected. In addition, several genes presumably involved in detoxification pathways were up-regulated. Comparative 2D gel electrophoresis of proteins extracted from the midgut revealed 388 protein spots, of which 7% were significantly affected in their levels by DFB treatment as determined by laser densitometry. Mass spectrometric identification revealed that UDP-N-acetylglucosamine pyrophosphorylase and glutathione synthetase were up-regulated. In summary, the red flour beetle turned out to be a good model organism for investigating the global effects of bioactive materials such as insect growth regulators and other insecticides. The results of this study recapitulate all of the different DFB-induced symptoms in a single model insect, which have been previously found in several different insect species, and further illustrate that DFB-treatment causes a wide range of effects at the molecular level.

In the past decade, researchers have put forth a lot of efforts to conceive a precise structural arrangement and properties of deep eutectic solvents (DESs) that provide designer pathways in order to broaden the application domain of these solvents. However, these contributions are limited to a few experimental and computational techniques. In this review, we have encompassed experimental techniques employed to establish the structure−property relationship of bulk DESs along with recent growth witnessed in this domain from a computational perspective. The nanostructuring plays an important role in various task specific applications of DESs. These solvents are found to exhibit unique heterogeneity at nanolength scales, the origin of which is unique and primarily depends on the constituent species involved. The hygroscopic nature of some DESs makes it crucial to explore the structural anatomy of hydrated DESs. Hence, this opens another subdomain to explore the impact of hydration on the bulk microscopic structure of DES and to know whether the nature is destructuring or structuring with respect to the neat solvents. This review highlights the recent successes attained in developing a thorough bulk microstructural understanding of neat and hydrated DESs.

Factors governing the stability and activity of proteins and enzymes in nonaqueous solvents have just been started to be explored. Because of their benign and economically viable nature, deep eutectic solvents (DESs) are being seen as an alternative media in many biotransformation processes. The present study exploits the changes in the conformation and stability of hen egg white lysozyme (HEWL) in the presence of reline (a eutectic mixture of choline chloride and urea) and reline/water mixtures using atomistic molecular dynamics simulations. The lysozyme structure was found to be partially folded in both reline and reline/water mixtures. Root-mean-square deviation (RMSD) of the positions of Cα atoms of lysozyme indicate that 50/50 reline/water solvent induces more destabilization in the conformation of HEWL than that by pure reline and 75/25 reline/water mixture. From the root-mean-square fluctuation (RMSF) analysis, it is found that the lysozyme active site (Glu35-Asp52) is quite stable in the presence of pure reline but it is least stable in the presence of 50/50 reline/water mixture. Our results show that the secondary structure of the lysozyme is significantly affected in the presence of reline. Our further analysis reveals that the hydrogen bonding interaction between HEWL–[Ch]+ dominates over HEWL–urea and HEWL–Cl– in pure reline than in reline/water mixtures.

Emergence of multi-drug resistant pathogens has fueled the search for alternatives to the existing line of antibiotics that can eradicate pathogens without inducing resistance development. Here, we report the accelerated...

Background:Periodontal diseases are microbial induced chronic inflammatory conditions characterized by infiltration of leukocytes, loss of connective tissue, alveolar bone resorption, and formation of periodontal pockets. In response to periodontal pathogens, the leukocytes (PMN) elaborate destructive oxidants, proteinases and other factors. The balance between these factors, the antioxidants and endogenously synthesized antiproteinases determine the extent of periodontal damage. Diabetes mellitus is a metabolic disorder. Most of the complications of diabetes are due to hyperglycemia. Persons with diabetes are at a greater risk for periodontal disease Malnutrition is characterized by marked tissue depletion of antioxidant nutrients and impaired acute phase protein response to infections resulting in impaired healing. Diabetes mellitus also alters the micronutrient levels. Malnutrition is characterized by marked tissue depletion of antioxidant nutrients and impaired acute phase protein response to infections resulting in impaired healing. Malnutrition, which usually involves concomitant deficiencies of several essential macro and micro nutrients, therefore, has the potential to adversely influence the prognosis of periodontal infections. Objectives:This study has been conducted to evaluate and compare the serum levels of vitamin C, zinc and copper in diabetic and healthy individuals with periodontitis.Materials and Methods:In this case control study 60 subjects inclusive of both sexes were selected and divided into 3 groups of 20 each. Group 1 comprised of 20 subjects with type 2 diabetes mellitus and periodontal disease, Group 2 comprised of 20 healthy subjects with periodontal disease. And Group 3 comprised of 20 healthy subjects without periodontal disease. Venous blood samples were collected and centrifuged at 3000rpm for 15 minutes and the superanatant serum is collected to measure the vitamin C, zinc and copper levels. The vitamin C levels of clinical samples were measured using spectrophotometric quantitation (dinitrophenyl hydrazine method) and zinc and copper levels were measured using atomic absorption spectrophotometry.Results:The results showed that the levels of vitamin C and zinc decreased and copper levels increased in diabetic patients with periodontits compared to healthy individuals with periodontitis.Conclusion:It may be reasonable to suggest vitamin and/or mineral supplements for patients whose nutrition might be inadequate. Future research should focus on an evaluation of which nutrients may help to prevent the onset and progression of periodontal disease

DNA strand consisting of multiple runs of guanines can adopt the non-canonical, four-stranded DNA secondary structure known as G-quadruplex or G4 DNA. G4 DNA is thought to play an important role in transcriptional and translational regulation of genes, DNA replication, genome stability, and oncogene expression in eukaryotic genomes. In other organisms including several bacterial pathogens and some plant species, the biological role of G4 DNA and G4 RNA is starting to be explored. Recent investigation showed that G4 DNA and G4 RNA are generally conserved across plant species. In silico analyses of several bacterial genomes identified the putative guanine-rich, G4 DNA-forming sequences in the promoter regions. They were particularly abundant in certain gene classes, suggesting that these highly diverse structures can be employed to regulate expression of genes involved in secondary metabolite synthesis and signal transduction. Furthermore, in the pathogen Mycobacterium tuberculosis, the distribution of G4 motifs and their potential role in the regulation of gene transcription advocate for the use of G4 ligands to develop novel antitubercular therapies. In this review, we discuss the various roles of G4 structures in bacterial DNA and the application of G4 DNA as an inhibitor or therapeutic agent to tackle the bacterial pathogens.

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The global concern over the environmental impact and challenges associated with the use of conventional solvents in bio-transformation processes have pushed the search for alternative solvents. Recently, deep eutectic solvents...