DMBA induced DNA damage and repair in mammary epithelial cells in vitro measured by a nick translation assay

A new E. coli DNA polymerase I directed nick translation assay was used for measuring 7,12-dimethylbenz[a]anthracene-induced in situ DNA damage and repair in mouse mammary epithelial cells in monolayer culture. The nick translation assay was capable of detecting a DMBA-dose dependent significant increase of DNA damage, and the same assay also allowed monitoring of the DNA repair activity provoked by DMBA treatment of the epithelial cells. This relatively simple method thus provides a rapid assay for carcinogen-induced in situ DNA damage and repair in an epithelial cell tumorigenic system.     

Growth Stimulation by Conditioned Medium and Spermidine in Low-Density Suspension Cultures of Rice

Suspension cultures of Oryza sativa L. var IR 20 grew in Murashigeand Skoog medium (MS) supplemented with 2,4-D and kinetin ina density-dependant manner with a critical minimum inoculation-densityof 10,000 cells ml^–1. Conditioned medium obtained fromthese cultures and added to MS+2,4-D+kinetin induced the growthof cultures at 1,000 cells ml^–1. Growth stimulation byconditioned medium was mimicked by spermidine but not by otherpolyamines viz. putrescine and spermine. This is the first reportof a polyamine substituting for conditioned medium in cultures. ² Present address: Vice-Chancellor, Pondicherry University,Pondicherry 605 014, India.     

Screening of chemopreventive effect of naringenin-loaded nanoparticles in DMBA-induced hamster buccal pouch carcinogenesis by FT-IR spectroscopy

The aim of the present study is to investigate the chemopreventive effects of the prepared naringenin-loaded nanoparticles (NARNPs) relative to efficacy of free naringenin (NAR) in modifying the functional, structural, and compositional changes at the molecular level during 7, 12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis by Fourier transform infrared (FT-IR) spectroscopy. The results revealed that a significant increase in the amount of proteins and nucleic acid contents and a decrease in the amount of lipids and glycogen contents are observed in DMBA-induced tumor tissues. In addition, in tumor tissues a decrease in lipid order and a significant increase in membrane dynamics were noticed. Further, the composition and secondary structure of proteins were found to be altered, which indicates some important structural alterations in the existing proteins and/or the expression of new types of proteins occurring under the tumor transformation. Furthermore, oral administration of free NAR and NARNPs significantly increased lipids and their order as well as increased the glycogen contents and decreased the levels of proteins and nucleic acid contents. On a comparative basis, NARNPs were found to have a more potent antitumor effect than free NAR in completely preventing the formation of squamous cell carcinoma and in improving the biochemical constituents to a normal range in DMBA-induced HBP carcinogenesis. The present study further shows a great potential of FT-IR spectroscopy as a complimentary tool for the screening of various anticancer drugs and follow-up, which may allow faster response to critical problems arising during treatment.     

Insecticidal activity of Origanum majorana L. essential oil as anti‐cholinergic agent

The present study was focused on exploring the presence of active compounds in Origanum majorana essential oil (OmEO), and its various knock‐down effects against the rice moth, Corcyra cephalonica. GC–MS analysis detected the existence of major compounds such as monoterpenes, cis‐β‐terpineol and terpinen‐4‐ol with the total proportion of 52.16%. Fumigant toxicity against adult and larvae was calculated with an LC₅₀ value of 11.31 and 49.83 μL/L air, respectively. The contact toxicity against adult, pupa, larvae and eggs was observed with LC₅₀ value 2.54, 0.95, 2.78, and 0.49 μL/L, respectively. Furthermore, the influential repellent behavior against adults has been observed. Acetylesterase (AChE) inhibition activity of OmEO was observed against adult and larvae of C. cephalonica with an IC₅₀ value of 35.89 and 118.54 μL/mL, respectively. Moreover, computational docking study revealed the binding affinity of Cis‐β‐terpineol and terpinen‐4‐ol towards the active binding sites of AChE. On the other hand, Fluorescence‐assisted cytometry and comet assay confirmed the cytotoxic and genotoxic effect of OmEO at various concentrations on C. cephalonica. Altogether, the results showed the knock‐down effect of OmEO against C. cephalonica, and it could be a potential biocontrol measure against the stored product pest.     

丛枝菌根真菌促进南美蟛蜞菊生长及对难溶磷的吸收

为了解2种丛枝菌根真菌(AMF)摩西管柄囊霉(Funneliformis mosseae, FM)和地表球囊霉(Glomus versiforme, GV)对入侵植物南美蟛蜞菊(Wedelia trilobata)的生长和对难溶性磷酸盐利用的影响,采用沙培盆栽方式,研究了南美蟛蜞菊在接种AMF与添加难溶性磷酸盐的生长和磷含量的变化。结果表明,在磷限制环境下FM对南美蟛蜞菊的侵染率达55%～69%,GV的侵染率达到63%～80%。添加难溶性磷酸盐后,2种AMF均促进了南美蟛蜞菊茎的伸长(FM:+46%; GV:+65%)、总生物量的增加(FM:+27.2%; GV:+40%)和磷含量的增加(FM:+36.6%; GV:+40.7%)。对比FM,GV对植物利用难溶性磷有更显著的促进作用。因此,南美蟛蜞菊与2种AMF形成的共生体系可以促进植物生长和对营养资源的利用,提高对难溶性磷的吸收效率可能使得南美蟛蜞菊在营养贫乏的环境中更好地建立种群。     

Highly Stable Plasmonic Nanostructures on a Nickel-Sputtered Glass and Polymeric Optical Fiber Sensors

Plasmonics - This study shows development of highly sensitive and stable localized surface plasmon resonance (LSPR)-active U-bent glass and polymeric optical fiber (GOF and POF) sensor probes by a...     

Molecular identification and functional analysis of Niemann-Pick type C2 protein in Macrocentrus cingulum Brischke (Hymenoptera: Braconidae)

Niemann-Pick type C2 (NPC2) proteins in arthropods have been extensively differentiated and possibly duplicated according to environmental conditions and are probable to have different functions. The participation of NPC2 proteins in chemical communication in arthropods brings new objectives in environmental-friendly strategies for pest population control. In this study, NPC2 gene in Macrocentrus cingulum (McinNPC2) was newly identified by rapid amplification cDNA ends (RACE) technology. McinNPC2 amino acid sequence alignment with other representative NPC2 annotates to evaluate the highly conserved consensus amino acids, but with odorant binding proteins in M. cingulum show that only one consensus amino acid. Primary six-cysteine structures that are same to odorant binding proteins in M. cingulum were observed in McinNPC2. Phylogenetic analysis of McinNPC2 indicated that the nearest monophyletic group forming one clade with high posterior probability values clusters as Cyphomyrmex costatus (CcosNPC2) whereas the nearest evolutionary relation group as some odorant binding proteins. Moreover, quantitative real-time PCR (qPCR) measurements show that the McinNPC2 gene expression level in various tissues of the female is significantly and ubiquitously higher than in male, whereas the highest expression level in female antennae. We further explore the binding characterization of recombinant McinNPC2 to candidate odor molecules and did the modeling and docking simulations. The results showed ligands binding specificity and docking tests results indicate that β-ionone, an aroma compound commonly found in essential oils, can strongly bind with McinNPC2. In conclusion, we proposed that McinNPC2 may be involved in chemical communication and play roles in perception of plant volatiles.     

Anti-biofilm activity of LC-MS based Solanum nigrum essential oils against multi drug resistant biofilm forming P. mirabilis

Urinary tract infections are second most important diseases worldwide due to the increased amount of antibiotic resistant microbes. Among the Gram negative bacteria, P. mirabilis is the dominant biofilm producer in urinary tract infections next to E. coli. Biofilm is a process that produced self-matrix of more virulence pathogens on colloidal surfaces. Based on the above fact, this study was concentrated to inhibit the P. mirabilis biofilm formation by various in-vitro experiments. In the current study, the anti-biofilm effect of essential oils was recovered from the medicinal plant of Solanum nigrum, and confirmed the available essential oils by liquid chromatography-mass spectroscopy analysis. The excellent anti-microbial activity and minimum biofilm inhibition concentration of the essential oils against P. mirabilis was indicated at 200 µg/mL. The absence of viability and altered exopolysaccharide structure of treated cells were showed by biofilm metabolic assay and phenol–sulphuric acid method. The fluorescence differentiation of P. mirabilis treated cells was showed with more damages by confocal laser scanning electron microscope. Further, more morphological changes of essential oils treated cells were differentiated from normal cells by scanning electron microscope. Altogether, the results were reported that the S. nigrum essential oils have anti-biofilm ability.