Testing the efficacy of a chilli-tobacco rope fence as a deterrent against crop-raiding elephants

Chilli-based repellents have shown promise as deterrents against crop-raiding elephants in Africa. We experimented with ropes coated with chilli-based repellent as a cheap alternative to existing elephant cropraid deterrent methods in India. Three locations (Buxa Tiger Reserve, Wyanad Wildlife Sanctuary and Hosur Forest Division) representing varying rainfall regimes from high to low, and with histories of intense elephant-agriculture conflict, were selected for the experiments that were conducted over 2-3 months during the pre-harvest period of the kharif season in late 2006. Chilli and tobacco powder mixed with waste oil was applied to ropes strung around agricultural fields of 1.4-5.5 km perimeter and elephant approaches were monitored. Elephants breached the rope fences a few times at all three study sites. Female-led herds were far more deterred (practically 100% reduction) than were solitary males (c. 50%) by the chilli-tobacco rope. Efficacy of this method as a deterrent was significantly better in the low-rainfall regime relative to medium and high-rainfall regimes. The initial promising results present a case for more rigorous experimentation; these would help determine if the elephants avoiding the rope are responding physiologically to the chilli-tobacco smell or merely reacting cautiously to a novel substance in their environment.

Syntheses, Transfection Efficacy and Cell Toxicity Properties of Novel Cholesterol-based Gemini Lipids having Hydroxyethyl Head group

We have synthesized five new cholesterol based gemini cationic lipids possessing hydroxyethyl (-CH2CH2OH) function on each head group, which differ in the length of the polymethylene spacer chain. These gemini lipids are important for gene delivery processes as they possess pre-optimized molecular features, e. g., cholesterol backbone, ether linkage and a variable spacer chain between both the headgroups of the gemini lipids. Cationic liposomes were prepared from each of these lipids individually and as a mixture of individual cationic gemini lipid and 1,2-dioleoyl phosphatidylethanolamine (DOPE). Each gemini lipid based formulation induced better transfection activity than that of their monomeric counterpart. One such gemini lipid with a -(CH2)(12)-spacer, HG-12, showed dramatic increase in the mean fluorescence intensity due to the expression of green-fluorescence protein (GFP) in the presence of 10% FBS compared to the conditions where there was no serum. Other gemini lipids retained their gene transfection efficiency without any marked decrease in the presence of serum. The only exception was seen with the gemini with a -(CH2)(3)-spacer, HG-3, which on gene transfection in the presence of 10% FBS lost similar to 70% of its transfection efficiency. Overall the gemini lipid with a -(CH2)(5)-spacer, HG-5, showed the highest transfection activity at N/P (lipid/DNA) ratio of 0.5 and lipid : DOPE molar ratio of 2. Upon comparison of the relevant parameters, e. g., %-transfected cells, the amount of DNA transfected to each cell and %-cell viability all together against Lipofectamine 2000, one of the best commercial transfecting agents, the optimized lipid formulation based on DOPE/HG-5 was found to be comparable. In terms of its ability to induce gene-transfer in the presence of serum and shelf-life DOPE/HG-5 liposome was found to be superior to its commercial counterpart. Confocal imaging analysis confirmed that in the presence of 10% serum using a Lipid : DOPE of 1 : 4 and N/P charge ratio of 0.75 with 1.2 mu g DNA per well, HG-5 is better than Lipofectamine 2000.

Immunotherapeutic efficacy of Mycobacterium indicus pranii in eliciting anti-tumor T cell responses: Critical roles of IFN gamma

Mycobacterium indicus pranii (MIP) is approved for use as an adjuvant (Immuvac/Cadi-05) in the treatment of leprosy. In addition, its efficacy is being investigated in clinical trials on patients with tuberculosis and different tumors. To evaluate and delineate the mechanisms by which autoclaved MIP enhances anti-tumor responses, the growth of solid tumors consisting of Sp2/0 (myeloma) and EL4 (thymoma) cells was studied in BALB/c and C57BL/6 mice, respectively. Treatment of mice with a single intra-dermal (i.d.) injection of MIP 3 days after Sp2/0 implantation greatly suppresses tumor growth. MIP treatment of tumor bearing mice lowers Interleukin (IL)6 but increases IL12p70 and IFN? amounts in sera. Also, increase in CD8+ T cell mediated lysis of specific tumor targets and production of high amounts of IL2 and IFN? by CD4+ T cells upon stimulation with specific tumor antigens in MIP treated mice is observed. Furthermore, MIP is also effective in reducing the growth of EL4 tumors; however, this efficacy is reduced in Ifn?-/- mice. In fact, several MIP mediated anti-tumor responses are greatly abrogated in Ifn?-/- mice: increase in serum Interleukin (IL)12p70 amounts, induction of IL2 and lysis of EL4 targets by splenocytes upon stimulation with specific tumor antigens. Interestingly, tumor-induced increase in serum IL12p70 and IFN? and reduction in growth of Sp2/0 and EL4 tumors by MIP are not observed in nonobese diabetic severe combined immunodeficiency mice. Overall, our study clearly demonstrates the importance of a functional immune network, in particular endogenous CD4+ and CD8+ T cells and IFN?, in mediating the anti-tumor responses by MIP.

NMR Structure Implications of Enhanced Efficacy of Obestatin Fragment Analogs

Obestatin is a more recently discovered hormone that is encoded by the ghrelin gene and produced in the stomach and gut. We report NMR analysis on synthetic Obestatin (OB23), a 23 residue peptide, along with three overlapping fragments of the same in methanol solvent as a first step towards structure activity relationship. Selective substitutions on the promising N-terminal and middle fragments of obestatin have been carried out in order to improve the efficacy and potency. In the N-terminal fragment two peptides were obtained by the replacement of Gly (8) with a-aminoisobutyric acid (Aib, U) and Phe (F5) with Cyclohexylalanine (Cha). In case of the middle fragment both Gly (3) and Gly (8) were replaced with Aib residues. The rationale being, these unusual amino acids could provide protection from immediate degradation and aid structure stabilization. Our previous studies showed that the N-terminal and the middle fragment were unstructured and hence this substitution would directly evaluate the effect of structure on the activity of these fragment analogs. Detailed NMR analysis clearly demonstrates formation of helical secondary structure in all the peptide analogues and provides justification for relative activities reported by our group previously (Nagaraj et al. 2009).

Treatment efficacy of algae-based sewage treatment plants

Lagoons have been traditionally used in India for decentralized treatment of domestic sewage. These are cost effective as they depend mainly on natural processes without any external energy inputs. This study focuses on the treatment efficiency of algae-based sewage treatment plant (STP) of 67.65 million liters per day (MLD) capacity considering the characteristics of domestic wastewater (sewage) and functioning of the treatment plant, while attempting to understand the role of algae in the treatment. STP performance was assessed by diurnal as well as periodic investigations of key water quality parameters and algal biota. STP with a residence time of 14.3 days perform moderately, which is evident from the removal of total chemical oxygen demand (COD) (60 %), filterable COD (50 %), total biochemical oxygen demand (BOD) (82 %), and filterable BOD (70 %) as sewage travels from the inlet to the outlet. Furthermore, nitrogen content showed sharp variations with total Kjeldahl nitrogen (TKN) removal of 36 %; ammonium N (NH4-N) removal efficiency of 18 %, nitrate (NO3-N) removal efficiency of 22 %, and nitrite (NO2-N) removal efficiency of 57.8 %. The predominant algae are euglenoides (in facultative lagoons) and chlorophycean members (maturation ponds). The drastic decrease of particulates and suspended matter highlights heterotrophy of euglenoides in removing particulates.

Experimental assessment of concrete damage due to exposure to high temperature and efficacy of the repair system

The present study experimentally evaluates the performance of control (standard cylinder specimen), damaged (mechanical loading after thermal exposure) and repaired / retrofitted normal plain concrete cylinders using different repair schemes such as on use of FRP wraps, Geo-polymers, etc., to restore the capacity of damaged structural concrete elements. The control-companion specimen in the series provides the reference frame against which both, specimen damage levels were quantified and the benefits of a specimen repaired subsequent to damage were assessed.

Formulation of nanotized curcumin and demonstration of its antimalarial efficacy

Aim: The present study was conducted to overcome the disadvantages associated with the poor water solubility and low bioavailability of curcumin by synthesizing nanotized curcumin and demonstrating its efficacy in treating malaria. Materials and methods: Nanotized curcumin was prepared by a modified emulsion-diffusion-evaporation method and was characterized by means of transmission electron microscopy, atomic force microscopy, dynamic light scattering, Zetasizer, Fourier transform infrared spectroscopy, and differential thermal analysis. The novelty of the prepared nanoformulation lies in the fact that it was devoid of any polymeric matrices used in conventional carriers. The antimalarial efficacy of the prepared nanotized curcumin was then checked both in vitro and in vivo. Results: The nanopreparation was found to be non-toxic and had a particle size distribution of 20-50 nm along with improved aqueous dispersibility and an entrapment efficiency of 45%. Nanotized curcumin (half maximal inhibitory concentration IC50]: 0.5 mu M) was also found to be ten-fold more effective for growth inhibition of Plasmodium falciparum in vitro as compared to its native counterpart (IC50: 5 mu M). Oral bioavailability of nanotized curcumin was found to be superior to that of its native counterpart. Moreover, when Plasmodium berghei-infected mice were orally treated with nanotized curcumin, it prolonged their survival by more than 2 months with complete clearance of parasites in comparison to the untreated animals, which survived for 8 days only. Conclusion: Nanotized curcumin holds a considerable promise in therapeutics as demonstrated here for treating malaria as a test system.

Enhanced Efficacy of Pluronic Copolymer Micelle Encapsulated SCR7 against Cancer Cell Proliferation(a)

5,6-Bis(benzylideneamino)-2-mercaptopyrimidin-4-ol (SCR7) is a new anti cancer molecule having capability to selectively inhibit non-homologous end joining (NHEJ), one of the DNA double strand break (DSB) repair pathways inside the cells. In spite of the promising potential as an anticancer agent, hydrophobicity of SCR7 decreases its bioavailability. Herein the entrapment of SCR7 in Pluronic copolymer is reported. The size of the aggregates was determined by transmission electron microscopy (TEM) and dynamic light scattering (DLS) which yields an average diameter of 23 nm. SCR7 encapsulated micelles (ES) were also characterized by small-angle neutron scattering (SANS). Evaluation of its biological properties by using a variety of techniques, including Trypan blue, MTT and Live-dead cell assays, reveal that encapsulated SCR7 can induce cytotoxicity in cancer cell lines, being more effective in breast cancer cell line. Encapsulated SCR7 treatment resulted in accumulation of DNA breaks within the cells, resulting in cell cycle arrest at G1 phase and activation of apoptosis. More importantly, we found approximate to 5 fold increase in cell death, when encapsulated SCR7 was used in comparison with SCR7 alone.

Green Nanosilver as Reinforcing Eco-Friendly Additive to Epoxy Coating for Augmented Anticorrosive and Antimicrobial Behavior

Epoxy resin GY250 representing diglycidyl ethers of bisphenol-A (DGEBA) was reinforced with 1, 3 and 5 wt % of surface functionalized silver nanoparticles (F-AgNPs) which were synthesized using Couroupita guianensis leaves extract with a view of augmenting the corrosion control property of the epoxy resin and also imparting antimicrobial activity to epoxy coatings on mild steel. Corrosion resistance of the coatings was evaluated by EIS, potentiodynamic polarization studies and cross scratch tests. AFM, SEM, HRTEM and EDX were utilized to investigate the surface topography, morphology and elemental composition of the coatings on MS specimens. Results showed that the corrosion resistance, hardness and T-g of the DGEBA/F-AgNPs coatings increased at 1 wt % of F-AgNPs. The DGEBA/F-AgNPs coatings also offered manifold antimicrobial protection to the MS surfaces by inhibiting the growth of biofilm forming bacteria like P. aeruginosa, B. subtilis, the most common human pathogen E. coli and the most virulent human pathogenic yeast C. albicans.

Use of Sediment Bioassays to Verify Efficacy of Caulerpa taxifolia Eradication Treatments

Infestations of the marine macrophytic alga Caulerpa taxifolia were discovered in Agua Hedionda Lagoon, California in 2000. Rapid response actions included containment under pvc tarps coupled with injection of liquid sodium hypochlorite. To assess the efficacy of these treatments, replicated sediment cores were removed from representative treated sites and transferred to grow-out facilities. Similar cores from uninfested (control) sediments were removed, inoculated with viable explants of C. taxifolia and placed in grow-out facilities. Results from two sampling periods (1 year, 2 years post-treatment) showed that no viable C. taxifolia emerged in cores, and that inoculated “control” sediments supported normal growth. Eelgrass ( Zostera marina L.) seedlings emerged from native seed-banks in “treated” cores, which also supported growth of some invertebrates (annelid worms and hydroids). This study provided essential verification of C. taxifolia eradication efforts, and demonstrates the feasibility of incorporating quality control/quality assurance components in rapid response actions. Results of this study also suggest that seeds of eelgrass are viable for at least two years. (PDF has 9 pages.)

Comparative Efficacy of Diquat for Control of Two Members of the Hydrocharitaceae: Elodea and Hydrilla

The submersed plants hydrilla (Hydrilla verticillata (L.f.) Royle) and elodea (Elodea canadensis Rich.) are both members of the Hydrocharitaceae family and cause problems in waterways throughout the world. Diquat (6,7-dihydrodipyrido[1,2-α:2’,1’-c]pyrazinediium dibromide) is a contact herbicide used to control nuisance submersed and floating aquatic macrophytes. There is no readily available information in the literature on the control of elodea under various diquat concentration and exposure times (CET) and other than a study by Van et. al 1987, little on hydrilla. Since CET relationships are critical in controlling submersed plants in areas influenced by water exchange, this study was designed to evaluate the efficacy of diquat on hydrilla and elodea under various CET scenarios. (PDF has 3 pages.)