Synthesis and characterization of metal ion imprinted nano-porous polymer for the selective recognition of copper

Selective recognition of metal ions utilizing metal ion-imprinted polymers (MIIPs) received much importance in diverse fields owing to their high selectivity for the target metal ions. In the present study, a copper ion imprinted polymer was synthesized without an additional complexing ligand or complex with a broad aim to avoid the conventional extra metal ion complexing ligand during the synthesis of MIIP. The complete removal of the copper metal ion from the MIIP was confirmed by AAS and SEM–EDX. SEM image of the MIIP exhibited nano-patterns and it was also found to be entirely different from that of non-imprinted polymer and polymer with copper metal ions. BET surface area analysis revealed more surface area (47.96 m²/g) for the Cu(II)-MIIP than non-imprinted control polymer (41.43 m²/g). TGA result of polymer with copper metal ion indicated more char yield (18.41%) when compared to non-imprinted control polymer (8.3%) and Cu(II)-MIIP (less than 1%). FTIR study confirmed the complexation between Cu(II)-MIIP and Cu(II) metal ion through carbonyl oxygen of acryl amide. The Cu(II)-MIIP exhibited an imprinting efficiency of 2.0 and it was showing 8% interference from a mixture of Zn, Ni and Co ions. A potentiometric ion selective electrode devised with Cu(II)-MIIP showed more potential response for Cu(II) ion than that was fabricated from non-imprinted polymer.     

Effects of environmental air pollution on endogenous oxidative DNA damage in humans

Epidemiological studies conducted in metropolitan areas have demonstrated that exposure to environmental air pollution is associated with increases in mortality. Carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) are the major source of genotoxic activities of organic mixtures associated with respirable particulate matter, which is a constituent of environmental air pollution. In this study,we wanted to evaluate the relationship between exposure to these genotoxic compounds present in the air and endogenous oxidative DNA damage in three different human populations exposed to varying levels of environmental air pollution. As measures of oxidative DNA damage we have determined 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) by liquid chromatography–tandem mass spectrometry (LC–MS/MS) and cyclic pyrimidopurinone N-1,N² malondialdehyde-2′-deoxyguanosine (M₁dG) by the immunoslot blot assay from lymphocyte DNA of participating individuals. The level of endogenous oxidative DNA damage was significantly increased in individuals exposed to environmental air pollution compared to unexposed individuals from Kosice (8-oxodG adducts) and Sofia (M₁dG adducts). However, there was no significant difference in the level of endogenous oxidative DNA and exposure to environmental air pollution in individuals from Prague (8-oxodG and M₁dG adducts) and Kosice (M₁dG adducts). The average level of M₁dG adducts was significantly lower in unexposed and exposed individuals from Kosice compared to those from Prague and Sofia. The average level of 8-oxodG adducts was significantly higher in unexposed and exposed individuals from Kosice compared to those from Prague. A significant increasing trend according to the interaction of c-PAHs exposure and smoking status was observed in levels of 8-oxodG adducts in individuals from Kosice. However, no other relationship was observed for M₁dG and 8-oxodG adduct levels with regard to the smoking status and c-PAH exposure status of the individuals. The conclusion that can be made from this study is that environmental air pollution may alter the endogenous oxidative DNA damage levels in humans but the effect appears to be related to the country where the individuals reside. Genetic polymorphisms of the genes involved in metabolism and detoxification and also differences in the DNA repair capacity and antioxidant status of the individuals could be possible explanations for the variation observed in the level of endogenous oxidative DNA damage for the different populations.     

Comparative Membrane Channel Size and Activity of Botulinum Neurotoxins A and E

In an effort to compare the molecular basis of differential toxic activity of botulinum neurotoxin A (BoNT/A) and BoNT/E, we have analyzed their membrane channel activity by measuring calcein release from liposomes. Both BoNT/A and /E showed a same level of membrane channel activity that was specifically blocked by IgG specific to the neurotoxins. With the use of fluorescein-labeled dextran, we determined that the size of the channel is at least 24.2 A which is appropriate for the translocation of a protein of 50 kDa (the light chain of BoNT). These findings would suggest that the difference in the toxicity level of the two BoNT serotypes might reflect differences in either endopeptidase activity or their binding to receptor(s).     

Studies on mitotic and salivary chromosomes of Dacus cucurbitae Coquillett (Diptera: Trypetidae)

Dacus cucurbitae is a serious pest of various types of fleshy fruits and vegetables. The mitotic and salivary chromosomes were reinvestigated using the air-drying and different (C-and H-) banding techniques with a view to rectify the existing controversy regarding the Indian populations of this species. A standard map of its salivary chromosomes was constructed and some important identifiable landmarks were recognized in each arm.     

Efficacy of methyl 5(6)-(alpha-hydroxyphenylmethyl) benzimidazole-2-carbamate, a metabolite of mebendazole, against developing forms of experimental helminth parasites.

Methyl 5(6)-(alpha-hydroxyphenylmethyl) benzimidazole-2- carbamate, a metabolite of mebendazole, was evaluated against metamorphic forms of Ancylostoma ceylanicum in hamsters, Nippostrongylus brasiliensis in rats and cysticercoids of Hymenolepis nana in grain beetles. The test compound offered better action than mebendazole except against H. nana cysticercoids where the activity of the compound and mebendazole was comparable, but was inferior to the standard cestodicidal drug, praziquantel. The results suggest that the action was better by ip route compared to per os route of drug administration.     

Induced mutation in tomatillo (Physalis ixocarpa Brot.)

To induce mutation in tomatillo (Physalis ixocarpa Brot.) commonly grown for its fruit value, seeds were treated with three alkylating agents (dimethyl sulphate, diethyl sulphate and methyl ethane sulphonate) and gamma rays. Seven viable and five chlorophyll mutant types were screened both from M₁ and M₂ generations. The isolated mutant lines are described and evaluated with reference to their beneficial value.     

Tolerance to imidazolinone herbicides in wheat

An imidazolinone-tolerant wheat (Triticum aestivum L. em Thell) mutant in the winter wheat cultivar Fidel has been identified and characterized. The mutant was isolated from a population derived through seed mutagenesis of the variety with an aqueous solution containing sodium azide. Imidazolinone-tolerant wheat seedlings were selected from the M₂ generation of the population in the presence of imazethapyr herbicide and identified as herbicide-insensitive individuals. The trait is inherited as a single semidominant gene and confers high levels of tolerance to imazethapyr. Acetohydroxyacid synthase activity in extracts from imidazolinonetolerant plants was less inhibited by imazethapyr than the enzyme from the wild type. The herbicide-tolerant plants have a completely normal phenotype and display no negative effects on growth and yield in either the absence or presence of imazethapyr.     

Effect of temperature onin vitro pollen germination in pigeonpea

Pollen of pigeonpea(Cajanus cajan (L.) Millsp.) cultivars H-77-216 and ICPL-151 were cultivatedin vitro at six different temperatures (12, 17, 22, 27, 32, 37 °C). Pollen of cv. H-77-216 started to germinate at 17 °C whereas the pollen of cv. ICPL-151 at 22 °C, the optimal temperatures were 22 and 27 °C, respectively. Pollen germination at different temperatures was found to be positively correlated with the tube length. Per cent pollen bursting increased with rising temperature. The indeterminate cv. H-77-216 showed a wide range of suitable temperatures (17 – 27 °C) for pollen germination while the determinate cv. ICPL-151 had optimum at 27 °C     

Three cadinene derivatives and a prostaglandin-like acid from Chromolaena species

An investigation of the aerial parts of Chromolaena chasleae afforded a prostaglandin-like acid, whose structure followed from the ¹H NMR spectral data and from the reaction with periodate, which afforded a hemiacetal. From a new Chromolaena species, three novel cadinene derivatives were isolated, which were closely related to those isolated previously from this genus.     

Physiological and biochemical changes associated with cotton fibre development. II. Auxin oxidising system

Changes in IAA oxidase, and in cytoplasmic and ionically wall-bound peroxidase activities were studied in the developing fibres of three cotton cultivars ( Gossypium hirsutum L. cv. Gujarat-67, cv. Khandwa-2 and G. herbaceum L. cv. Digvijay), designated as long, medium and short staple cultivars, respectively. In all the three cultivars IAA oxidase activity was low during the fibre elongation phase, while the activity increased significantly during the secondary thickening phase. The increase in IAA oxidase activity in the three cultivars showed close correspondence with their respective total period of elongation. No relationship between cytoplasmic peroxidase activity and fibre development was discernible. The ionically bound wall peroxidase activity, however, recorded low levels during the elongation phase and higher levels during the secondary thickening phase. The role of wall peroxidase in cessation of elongation growth is discussed.