Bio-composite fibers were developed from wood pulp and polypropylene (PP) by an extrusion process. The thermo-physical and mechanical properties of wood pulp-PP composite fibers, neat PP and wood pulp were studied using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). The thermal stability of bio-composite fibers was found to be significantly higher than pure wood pulp. An understanding into the melting behaviour of the composite system was obtained which would assist in selecting a suitable temperature profile for the extruder during processing. The visco-elastic properties of bio-composite fibers were also revealed from the study. The generated bio-composite fibers were also characterized using Fourier transform infrared spectroscopy (FTIR) to understand the nature of chemical interaction between wood pulp reinforcement and PP matrix. The use of maleated polypropylene (MAPP) as a compatibilizer was investigated in relation to the fiber microstructure. Changes in absorption peaks were observed in FTIR spectra of bio-composite fibers as compared to the pure wood pulp which indicated possible chemical linkages between the fiber and polymer matrix.
The heavy metal lead is an environmental toxic material that can induce pathophysiological changes in many organ systems. Previous studies have shown the effects of lead exposure on immune cells in different experimental animals, however, the mechanism of their influence on the immune system is unclear. We reported that in vivo lead exposure inhibits phagocytosis, nitric oxide release, induces DNA fragmentation suggesting the apoptotic death of the target cell. We have also presented evidence that inhibition of macrophage functional responses implicated alteration of humoral and cell mediated immunity. In vivo exposure to lead acetate alters the phagocytic capacity of splenic macrophages as evident from the reduction of phagocytic index of control from 19,792±1385.69 to 8893 ± 893 in the treated group. The amount of nitric oxide released by the control cell 2.25 ± 0.125 µM is also reduced to 1.9375 ± 0.0625 µM upon in vivo lead treatment. Functional integrity of the target cell is also decreased after lead exposure as obtained from the percentage of DNA fragmentation. Control group shows 33.29 ± 0.11% of fragmented DNA, which is enhanced to 42.43 ± 0.725% following the lead treatment. A greater percentage of DNA fragmentation upon lead treatment probably indicating that the heavy metal induces apoptosis. The humoral immune response is also altered after lead exposure as indicated by the decrease of the antibody titre in control group from 1:2048 to1:128 in the treated group. From the DTH reaction, it was observed that the mean diameter of swollen foot pad of control mice is 0.329 ± 0.15 cm and that of lead treated mice is 0.274 ± 0.056 cm. It can, therefore, be suggested that lead inhibits normal functional activities of splenic leukocytes, particularly phagocytosis and also affects the functional integrity of cells by inducing DNA fragmentation. The study may demonstrate the usefulness of investigation of humoral immune system and leukocyte functions as sensitive parameters in detecting the effects of lead toxicity.
Authors:M. Chakraborty, I. Ghosh, S. Ojha, S. Dutta, and N. Chatterjee
Influence of an endomycorrhizal species
on the growth of two vegetable plants, namely,
and for reduction of the incidence of fusarial wilt disease under field condition was studied. VAM treated plants showed more vigor in terms of productivity parameters viz., plant height, number of branching twigs and fruit production. VAM and pathogen treated plants also showed positive effect of VAM-symbiont over control indicating reduction of pathogenic stress of the plant and give resistance. Leaf phosphate, chlorophyll content and percentage of mycorrhization were recorded highest when plants were singly inoculated with
. Synergistic effect of VAM and pathogen to increase on productivity vis-à-vis resistance was also studied in respect of polyphenol oxidase. The experimental findings indicated the potential use of
for improving the growth and imparting resistance of brinjal and tomato.
Two types of ammonium uranyl nitrate (NH4)2UO2(NO3)4·2H2O and NH4UO2(NO3)3, were thermally decomposed and reduced in a TG-DTA unit in nitrogen, air, and hydrogen atmospheres. Various intermediate
phases produced by the thermal decomposition and reduction process were investigated by an X-ray diffraction analysis and
a TG/DTA analysis. Both (NH4)2UO2(NO3)4·2H2O and NH4UO2(NO3)3 decomposed to amorphous UO3 regardless of the atmosphere used. The amorphous UO3 from (NH4)2UO2(NO3)4·2H2O was crystallized to γ-UO3 regardless of the atmosphere used without a change in weight. The amorphous UO3 obtained from decomposition of NH4UO2(NO3)3 was crystallized to α-UO3 under a nitrogen and air atmosphere, and to β-UO3 under a hydrogen atmosphere without a change in weight. Under each atmosphere, the reaction paths of (NH4)2UO2(NO3)4·2H2O and NH4UO2(NO3)3 were as follows: under a nitrogen atmosphere: (NH4)2UO2(NO3)4·2H2O → (NH4)2UO2(NO3)4·H2O → (NH4)2UO2(NO3)4 → NH4UO2(NO3)3 → A-UO3 → γ-UO3 → U3O8, NH4UO2(NO3)3 → A-UO3 → α-UO3 → U3O8; under an air atmosphere: (NH4)2UO2(NO3)4·2H2O → (NH4)2UO2(NO3)4·H2O → (NH4)2UO2(NO3)4 → NH4UO2(NO3)3 → A-UO3 → γ-UO3 → U3O8, NH4UO2(NO3)3 → A-UO3 → α-UO3 → U3O8; and under a hydrogen atmosphere: (NH4)2UO2(NO3)4·2H2O → (NH4)2UO2(NO3)4·H2O → (NH4)2UO2(NO3)4 → NH4UO2(NO3)3 → A-UO3 → γ-UO3 → α-U3O8 → UO2, NH4 UO2(NO3)3 → A-UO3 → β-UO3 → α-U3O8 → UO2.
Authors:D. H. Nagore, V. K. Ghosh, M. J. Patil, and A. M. Wahile
This paper describes a new, simple, precise, and accurate HPTLC method for quantification of (−)-epicatechin in the leaves of Cassia fistula. The leaves were separately extracted with methanol and water by both maceration and hot extraction (Soxhlet apparatus). Chromatographic separation of the drug was performed on aluminium foil silica gel 60 F254 plates with toluene-ethyl acetate-formic acid-methanol 20:12:4:4 (v/v) as mobile phase. Densitometric evaluation of the separated zone was performed at 280 nm. Epicatechin in the extract was satisfactorily resolved with RF 0.22 ± 0.02. The accuracy and reliability of the method were assessed by evaluation of linearity (200–800 ng per band), precision (method precision RSD 1.42% and instrumental precision RSD 1.12%), accuracy (98.12%), and specificity in accordance with ICH guidelines.
Authors:R. Dutta, M. Sudarshan, S. Bhattacharyya, V. Vijayan, S. Ghosh, V. Chakravortty, and S. Chintalapudi
Ferromanganese nodules found on the Ocean bed are complex heterogenous mixtures of several components. Two nodules from Central Indian Ocean Basin (CIOB) were analysed by proton induced X-ray emission (PIXE) technique using 3UD Tandem pelletron. The precision and the accuracy of this technique for chemical analyses has been confimed by analysing USGS Geological Standards. Thick sample targets were bombarded by 3 MeV protons for the multielemental analysis. GUPIX-96 software was used for spectral data analysis. Quantative estimate of K, Ca, Tl, V, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Mo, Ba, Ce, Tl and Pb has been ascertained. The occurrence of Ga, Ge, Rb and Zr in nodules from this region is reported for the first time. The role of manganese and iron oxide phases in determining the uptake of various trace elements from ocean water and bottom sediment pore water has been discussed.
Authors:A. Kumar, R.K. Dubey, K. Kant, D. Sasmal, M. Ghosh, and N. Sharma
Deltamethrin, a well-known type 2 synthetic pyrethroid insecticide, is a widespread environmental toxicant. It has potential to accumulate in body fluids and tissues due to its lipophilic characteristics. The immune system is among the most sensitive targets regarding toxicity of environmental pollutants. Various methods are available in the literature to analyze deltamethrin (DLM) concentration in plasma and tissues, but regarding the immune organs, only one gas chromatography–tandem mass spectrometry (GC–MS/MS) method (on spleen tissues) has been reported. In the present investigation, a rapid and sensitive high-performance liquid chromatography (HPLC) method has been developed and validated to determine DLM concentration in plasma, thymus, and spleen using zaleplone as an internal standard. Liquid chromatography (LC) separation is performed on an Agilent Zorbax® C8 column (250 mm × 4.6 mm, i.d., 5 μm) with isocratic elution using a mobile phase consisting of acetonitrile–5 mM KH2PO4 (70:30, v/v) at a flow rate of 1 mL min−1. The lower limit of quantification (LLOQ) for DLM is 10 ng mL−1 (plasma, thymus, and spleen). The method has been validated in terms of establishing linearity, specificity, sensitivity, recovery, accuracy, and precision (intra- and inter-day) and stabilities study. This validated method was successfully applied to a pharmacokinetic and tissue distribution study of DLM in mice.
Authors:D. Gupta, J. Chatterjee, R. Ghosh, A. Mitra, S. Roy, and M. Sarkar
Radish plant was collected along with root and soil from the nearby area of a Municipal Solid Waste dumping site of the metropolitan
city of Kolkata, West Bengal, India and analyzed for a wide range of elements using the EDXRF technique with a 109Cd point source and a Si(Li) detector. The samples comprized of the root-soil, root and leaves. For quality control purposes,
NIST standard reference material (SRM) 1648 Urban Particulate Matter had also been analyzed using the same procedure as for
the samples. Concentrations of elements with X-ray energies in the range of 3–20 keV in the soil around the root and their
uptake pattern by the root and the leaves have been estimated.
Authors:R. Pathak, A. Khuda Bukhsh, S. Dey, U. Ghosh, B. Sen Gupta, M. Semwal, and N. Bhattacharyya
The paper aims to investigate cytogenetic and apoptotic responses of γ-irradiation in a radio-resistant cell strain designated
as M5. Induced micronuclei, chromosomal aberrations, nuclear fragmentation and nucleosomal ladders by γ-irradiation were less
at equal doses in M5 cells in comparison with that obtained in the parental Chinese hamster V79 cells. However, at equal survival,
there were no differences in the end points studied. Results indicate that the residual damages that lead to reproductive
cell death also resulted in the cytogenetic and apoptotic responses. We speculate that the repair efficiency in M5 cells was
more efficient and increased DNA repair could be the cause of radiation resistance observed in M5 cells.