Browsing by Author "Madhu Yashpal"

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Anticestodal activity of endophytic Pestalotiopsis sp. on protoscoleces of hydatid cyst echinococcus granulosus
(2013) Vijay C. Verma; Mayank Gangwar; Madhu Yashpal; Gopal Nath
Surgery is still the main treatment in hydatidosis caused by Echinococcus, which is a global health problem in human and animals. So, there is need for some natural protoscolicidal agents for instillation to prevent their reoccurrence at therapeutic doses. In this present investigation, anticestodal activity of one of the endophytic fungi Pestalotiopsis sp. from Neem plant was observed on protoscoleces of hydatid cysts of Echinococcus granulosus. Viability of protoscoleces was confirmed by 0.1% aqueous eosin red stain method, where mortality was observed at different concentrations with respect to time. An average anticestodal activity was observed with different endophytic fungal strains, that is, Nigrospora (479 ± 2.9), Colletotrichum (469 ± 25.8), Fusarium (355 ± 14.5), and Chaetomium (332 ± 28.3) showing 64 to 70% protoscolicidal activity, except Pestalotiopsis sp. (581 ± 15.0), which showed promising scolicidal activity up to 97% mortality just within 30 min of incubation. These species showed significant reduction in viability of protoscoleces. This is the first report on the scolicidal activity of endophytic Pestalotiopsis sp. We conclude that ultrastructural changes in protoscoleces were due to endophytic extract suggesting that there may be some bioactive compounds that have selective action on the tegument layer of protoscoleces. As compared with that of standard drug used, endophytic species of Neem plant shows significant anticestodal activity. © 2013 Vijay C. Verma et al.
Controlled synthesis and magnetic properties of monodispersed ceria nanoparticles
(American Institute of Physics Inc., 2015) Sumeet Kumar; Manish Srivastava; Jay Singh; Samar Layek; Madhu Yashpal; Arnulf Materny; Animesh K. Ojha
In the present study, monodispersed CeO2 nanoparticles (NPs) of size 8.5 ± 1.0, 11.4 ± 1.0 and 15.4 ± 1.0 nm were synthesized using the sol-gel method. Size-dependent structural, optical and magnetic properties of as-prepared samples were investigated by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), high resolution transmission electron microscopy (HR-TEM), ultra-violet visible (UV-VIS) spectroscopy, Raman spectroscopy and vibrating sample magnetometer (VSM) measurements. The value of optical band gap is calculated for each particle size. The decrease in the value of optical band gap with increase of particle size may be attributed to the quantum confinement, which causes to produce localized states created by the oxygen vacancies due to the conversion of Ce4+ into Ce3+ at higher calcination temperature. The Raman spectra showed a peak at ∼461 cm-1 for the particle size 8.5 nm, which is attributed to the 1LO phonon mode. The shift in the Raman peak could be due to lattice strain developed due to variation in particle size. Weak ferromagnetism at room temperature is observed for each particle size. The values of saturation magnetization (Ms), coercivity (Hc) and retentivity (Mr) are increased with increase of particle size. The increase of Ms and Mr for larger particle size may be explained by increase of density of oxygen vacancies at higher calcination temperature. The latter causes high concentrations of Ce3+ ions activate more coupling between the individual magnetic moments of the Ce ions, leading to an increase of Ms value with the particle size. Moreover, the oxygen vacancies may also produce magnetic moment by polarizing spins of f electrons of cerium (Ce) ions located around oxygen vacancies, which causes ferromagnetism in pure CeO2 samples. © 2015 Author(s).
Formulation of rosuvastatin-loaded self-nanoemulsifying drug delivery system using box-behnken design
(2014) Mohd Neyaz Ahsan; Priya Ranjan Prasad Verma; Sandeep Kumar Singh; S. Samridhi; Madhu Yashpal
The objectives of present study were to understand the effect of formulation variables of self-nanoemulsifying drug delivery system (SNEDDS) of rosuvastatin (RSV). Box-Behnken design in conjunction with desirability function was used to evaluate the main effect, interaction effect and quadratic effect of independent formulation variables that included amounts of Acconon 200 E6, Cremophor RH40, and Lipoxol 300. For a better understanding of the selected variables for the optimal performance of RSV SNEDDS, the models were presented as three-dimensional response surface graphs. A fresh batch of optimized formulations and were prepared with optimized levels of the independent variables to yield dependent variables (Y1-Y6) values that were remarkably close to the predicted values. Drug excipient compatibility studies using the Fourier transform infrared spectroscopy, differential scanning calorimeter and x-ray diffraction indicated the absence of any incompatibility between RSV and selected excipients. The transmission electron microscopy of selected optimized SNEDDS of RSV showed the spherical shape of globules with no signs of coalescence and precipitation of RSV. The study demonstrates the use of Box-Behnken design for the preparation of RSV SNEDDS. The desirable goals can be obtained by systematic formulation approach in minimum possible time. © 2014 Copyright Taylor and Francis Group, LLC.
Histochemical analysis of glycoproteins in the secretory cells in the gill epithelium of a catfish, Rita rita (Siluriformes, Bagridae)
(Elsevier Ltd, 2009) Usha Kumari; Madhu Yashpal; Swati Mittal; Ajay Kumar Mittal
Glycoproteins (GPs) were visualised histochemically in the secretory cells - the mucous goblet cells (the type A and the type B), the serous goblet cells, the club cells and the epithelial cells in the gill epithelium of Rita rita. The type A mucous goblet cells, the type B mucous goblet cells and the epithelial cells elaborate GPs with oxidizable vicinal diols and GPs with sialic acid residue without O-acyl substitution. In addition, GPs with O-sulphate esters are elaborated by the type A and GPs with O-acyl sugars by the type B mucous goblet cells. GPs are absent in the serous goblet cells and are with oxidizable vicinal diols in low moieties in the club cells. The analysis of the results elucidates interesting differences in the composition and concentration of GPs in the mucus elaborated by the epithelium of the gill arches and the gill rakers; and the gill filaments and the secondary lamellae indicating the potential importance of the glycoproteins at these locations. GPs elaborated on the surfaces of the gill arches and the gill rakers could be associated to assist in feeding activities and on the surfaces of the gill filaments and the secondary lamellae in the respiratory activity. © 2009 Elsevier Ltd. All rights reserved.
Histochemical characterization of glycoproteins in the buccal epithelium of the catfish, Rita rita
(Elsevier GmbH, 2007) Madhu Yashpal; Usha Kumari; Swati Mittal; Ajay Kumar Mittal
Glycoproteins (GPs) elaborated by the buccal epithelium of the catfish, Rita rita, were analysed by a range of histochemical methods. These included methods for the characterization and simultaneous visualization of GPs with oxidizable vicinal diols, with O-acyl sugars, with O-sulphate esters and with sialic acid residues with and without O-acyl substitution at C7, C8 or C9. GPs elaborated at the surface of the buccal epithelium are primarily from two sources, the epithelial cells and the mucous goblet cells. They include GPs with O-sulphate esters, GPs with sialic acid residues without O-acyl substitution and GPs with oxidizable vicinal diols. Different classes of GPs have been associated with specific functions and are discussed in relation to their physiological significance, with special reference to their roles in lubrication, alteration in viscosity, trapping of food particles, buffering of fluids at the epithelial surface, prevention of proteoloytic damage to the epithelium, antimicrobial activity and defence against pathogens. The epithelium shows specialized modifications in the form of the buccal glands. These have been considered to increase the secretory surface that allows profuse secretion of mucus in a very short period of time. The secretions of these glands have been associated with multiple functions similar to those of saliva. © 2007 Elsevier GmbH. All rights reserved.
Morphological specializations of the buccal cavity in relation to the food and feeding habit of a carp Cirrhinus mrigala: A scanning electron microscopic investigation
(2009) Madhu Yashpal; Usha Kumari; Swati Mittal; Ajay Kumar Mittal
The buccal cavity of an herbivorous fish, Cirrhinus mrigala, was investigated by scanning electron microscopy to determine its surface ultrastructure. The buccal cavity shows significant adaptive modifications in relation to food and feeding ecology of the fish. The buccal cavity of the fish is of modest size and limited capacity, which is considered an adaptation with respect to the small-sized food items primarily consumed by the fish that could be accommodated in a small space. Modification of surface epithelial cells, on the upper jaw, into characteristic structures-the unculi-is considered an adaptation to browse or scrap, to grasp food materials, e.g., algal felts, and to protect the epithelial surface against abrasions, likely to occur during their characteristic feeding behavior. Differentiation of the highly specialized lamellar organ on the anterior region of the palate could be an adaptation playing a significant role in the selection, retention, and sorting out of palatable food particles from the unpalatable items ingested by the fish. The filamentous epithelial projections and the lingulate epithelial projections on the palatal organ in the posterior region of the palate are considered to serve a critical function in final selection, handling, maneuvering, and propelling the food particles toward the esophagus. The abundance of different categories of taste buds in the buccal cavity suggests that gustation is well developed and the fish is highly responsive in the evaluation and the selection of the preferred palatable food items. The secretions of mucous cells in the buccal cavity are associated with multiple functions-particle entrapment, lubrication of the buccal epithelium and food particles to assist smooth passage of food, and to protect the epithelium from possible abrasion. These morphological characteristics ensure efficient working of the buccal cavity in the assessment of the quality and palatability of ingested food, their retention and transport toward the esophagus. Such an adaptation may be essential in conducting the function most basic to the survival of the individuals and species-feeding. © 2009 Wiley-Liss, Inc.
Morphology of the pharyngeal cavity, especially the surface ultrastructure of gill arches and gill rakers in relation to the feeding ecology of the catfish Rita rita (Siluriformes, Bagridae)
(2005) Usha Kumari; Madhu Yashpal; Swati Mittal; Ajay Kumar Mittal
Gill arches and the gill rakers of a sluggish, carnivorous catfish, Rita rita, show significant differences of their surface ultrastructure, which are recognized adaptive modifications in relation to food and feeding ecology of fish. Gill rakers on the first and second pairs of gill arches are borne on the oral side and are long and stout at the epi-ceratobranchial union. Gill rakers on the third and fourth pairs of gill arches, in contrast, are borne on the oral and aboral sides and are relatively delicate and short. Long and stout gill rakers on the first and second pairs of gill arches are considered primarily to prevent entry of undesirably large food items into the pharynx. Two types of taste buds, Type I and Type II, occur on the gill arches and the gill rakers. The raised taste buds, located at the apical ends of the gill rakers on the third, fourth, and the fifth pairs of gill arches could increase gustatory efficiency in the pharynx. Differences in the distribution of taste buds on the pharyngeal sides of different gill arches indicate that the posterior part of the pharynx plays a more crucial role in gustation than does the anterior part. Co-occurrence of teeth and taste buds on the epi- and hypopharyngeal bones denotes that food processing and gustation occur simultaneously in the pharynx. Villiform and caniform teeth on the epi- and hypopharyngeal bones are associated with a complex food-processing cycle. Mucous secretions, oozing through mucous cell openings, provide lubrication facilitating smooth passage of food through the pharynx. The angle of curvature at the epi-ceratobranchial union of the first to fourth pairs of gill arches could assist the ventral drag of ceratobranchials in lowering of the pharyngeal floor, thus resulting in a great expansion of the pharynx, as needed to accommodate the large quantities of food captured. © 2005 Wiley-Liss, Inc.
Nanoparticle-induced controlled biodegradation and its mechanism in poly(ε-caprolactone)
(2010) Narendra K. Singh; Biswapratim Das Purkayastha; Jagat K. Roy; Rathindra M. Banik; Madhu Yashpal; Gajendra Singh; Sudip Malik; Pralay Maiti
Poly(ε-caprolactone) (PCL)/layered silicate nanocomposites have been prepared via solution route. Two different organically modified nanoclays were used to compare the variation in properties based on organic modifications. The nanostructures, as observed from wide-angle X-ray diffraction and transmission electron microscopy, indicate intercalated and partially exfoliated hybrids depending on the nature of organic modification in nanoclay. The nanohybrids exhibit significant improvement in thermal and mechanical properties of the matrix as compared to neat polymer. The nanoclays act as nucleating agent for the crystallization of PCL. The biodegradability of pure PCL and its nanocomposites have been studied under controlled conditions in enzyme, pure microorganism (fungi), compost, Ganges water, and alkaline buffer solution. The rate of biodegradation of PCL has enhanced dramatically in nanohybrids and depends strongly on the media used. Scanning confocal, electron, and atomic force microscopes have used to demarcate the nature of biodegradation of pristine PCL and its nanocomposites. The change in biodegradation is rationalized in terms of the crystallization behavior and organic modification in nanoclays of the nanohybrids vis-a-vis the neat polymer. The extent of compatibility was measured quantitatively through the interaction parameter for two different nanoclays to compare and establish the reason for variation in their properties in nanohybrids. A biodegradation mechanism has been revealed for PCL and its nanocomposites through enzyme activity in varying pH environment. © 2010 American Chemical Society.
Novel conducting lithium ferrite/chitosan nanocomposite: Synthesis, characterization, magnetic and dielectric properties
(Elsevier, 2014) Manish Srivastava; Jay Singh; Rajneesh K. Mishra; Manish K. Singh; Animesh K. Ojha; Madhu Yashpal; Srivastava Sudhanshu
A study on Lithium ferrite/chitosan nanocomposite (LFCN), easily moldable into arbitrary shapes, as the conducting polymer and ferromagnetic characteristics is presented. The composite material is produced in the presence of Li0.5Cr0.1Fe2.4O4 and Li 0.5Co0.1Fe2.4O4 nanoparticle by ex-situ polymerizations process. Various characterizations techniques have been used to explore the characteristic of the synthesized products. The frequency dependent dielectric properties and electrical conductivity of all the samples have been measured through complex impedance plot in the frequency range of 1 kHz-6 MHz at room temperature. It was observed that in case of (LFCN), fluctuation in value of (ε′) and (ε″) is ceased over the frequency range of 4 Mz which can be attributed to the steady storage and dissipation of energy in the nanocomposite system. Moreover, it is also observed that electrical conductivity of (LFCN) increases with frequency and its value was found to be (0.032-0.048) (ohm-cm)-1 in frequency range of 1 kHz-6 MHz. Due to its low cost, a simple synthesis process and high flexibility, the proposed LFCN may find applications in various types of electronic components. © 2014 Elsevier B.V. All rights reserved.
Rapid detection of enterotoxigenic Escherichia coli gene using bio-conjugated gold nano-particles
(2011) Anurag Jyoti; Surinder P. Singh; Madhu Yashpal; Premendra D. Dwivedi; Rishi Shanker
In this study, a simple gold nanoparticle based colorimetric detection system for on site diagnostics of Enterotoxigenic Escherichia coli (ETEC) has been developed. The developed assay could detect LT1 gene as evident from UV-visible spectra, the broadening of peak on hybridization of GNP probes with different copy numbers of the target gene.The present study suggests that hybridization induced changes in optical properties of GNPs can be translated into a rapid and simple colorometric" spot and read test detection method for ETEC. Copyright © 2011 American Scientific Publishers All rights reserved.
Room temperature ferromagnetism in undoped and Mn doped CdO nanostructures
(Elsevier, 2015) Sumeet Kumar; Samar Layek; Madhu Yashpal; Animesh K. Ojha
Cd1-xMnxO (x=00-0.07) nanostructures were synthesized and their structural, optical and magnetic properties were investigated. The shift of diffraction peaks towards lower angle side with increase of Mn content indicates the incorporation of Mn2+ ions into the CdO lattice. The values of optical band gaps were calculated at each value of Mn concentration. The values of band gap were increased by increasing the Mn concentrations as a direct consequence of the quantum confinement effect. The undoped CdO [Cd1-xMnxO (x=0.00)] nanostructure shows weak ferromagnetic nature at room temperature. The ferromagnetic nature increases consistently with increase of Mn concentrations from x=0.01 to 0.05 and then slightly drops for x=0.07. As there were no magnetic impurities present in the samples, we assume that the origin of ferromagnetism in the undoped CdO nanostructures could be due to formation of CdO structure in triplet state (S=1). However, the consistent increase of magnetic nature with Mn doped (x=0.01-0.05) CdO nanostructures might be attributed to the ferromagnetic coupling between the spins and enhancement of spin concentrations due to entering of Mn atom into the lattice. The sudden drop of ferromagnetic nature at x=0.07 may be due to the presence of anti-ferromagnetic coupling. © 2015 Elsevier B.V. All rights reserved.
Serous goblet cells: The protein secreting cells in the oral cavity of a catfish, Rita rita (Hamilton, 1822) (Bagridae, Siluriformes)
(Elsevier Ltd, 2014) Madhu Yashpal; Ajay Kumar Mittal
Serous goblet cells in the oral epithelium of Rita rita are characterized by the presence of distinct eosinophilic granules occupying large parts of the cytoplasm. In R. rita, a range of histochemical results reveal that these cells are involved in proteinaceous secretions, and thus likely contribute to various functions analogous to those of mammalian saliva. The secretions of these cells have also been associated with specific functions and are discussed in relation to their physiological importance with special reference to their roles in lubrication, alteration in viscosity, various functions of mucus such as handling, maneuvering and driving of food items toward the esophagus, maintaining taste sensitivity and protection of the oral epithelium. In addition, the serous goblet cells may also be considered as the primary defensive cell of the oral epithelium of R. rita. The results significantly add to very limited set of literature on the serous goblet cells and provide noteworthy information on the mucous secretions in the oral cavity of fish. © 2013 Elsevier Ltd.
Surface architecture of the mouth cavity of a carnivorous fish Rita rita (Hamilton, 1822) (Siluriformes, Bagridae)
(2006) Madhu Yashpal; Usha Kumari; Swati Mittal; Ajay Kumar Mittal
The topological characteristics of the mouth cavity of the carnivorous fish Rita rita were explored by means of scanning electron microscopy. The mouth cavity lining of R. rita may be distinguished into the roof and the floor. Papilliform teeth present on the premaxillae and the anterior regions of the dentaries are associated with seizing, grasping and holding of prey. The molariform teeth on the palatine regions and the dentaries are used for crushing and grinding of food items. The taste buds in the mouth cavity are of three types (types I, II, and III). The different types of taste buds are elevated from the epithelium at different levels, which may be useful for ensuring full utilization of the gustatory ability of the fish, detection and analysing of taste substances, as well as for assessing the quality and palatability of food, during its retention in the mouth cavity. A firm consistency or rigidity of the free surface of the epithelial cells may be attributed to compactly arranged microridges. These structures protect against physical abrasions potentially caused during food manoeuvring and swallowing. Furthermore, protection of the epithelium from abrasion is enhanced with mucous cell secretions, which lubricate ingested food items. Observations of the surface architecture of the mouth cavity of R. rita are discussed within the context of feeding and habitat preferences as well as ecomorphological adaptation of the species.
Synthesis of superparamagnetic bare Fe 3O 4 nanostructures and core/shell (Fe 3O 4/alginate) nanocomposites
(2012) Manish Srivastava; Jay Singh; Madhu Yashpal; Dinesh Kumar Gupta; R.K. Mishra; Shipra Tripathi; Animesh K. Ojha
In this article we report about the synthesis of superparamagnetic bare Fe 3O 4 nanostructures and core/shell (Fe 3O 4/alginate) nanocomposites by simple low-temperature based method at pH values 5, 9, and 14. The structural morphology and magnetic behavior of Fe 3O 4 nanostructures and core/shell (Fe 3O 4/alginate) nanocomposites (Fe 3O 4/alg NCs) have been investigated by X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy (RS), ultraviolet-visible (UV-vis) spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) and vibrating sample magnetometer (VSM). The particle size was calculated by TEM measurements and it turns out to be ∼10 nm and ∼14 nm for bare Fe 3O 4 nanoparticle and Fe 3O 4/alg NCs with core/shell structure, respectively. The magnetic properties of the synthesized products were found to be function of pH at which the synthesis has been done. The synthesized Fe 3O 4 nanoparticle and Fe 3O 4/alg NCs were found to be superparmagnetic in nature at room temperature. We observed that the value of saturation magnetization in case of Fe 3O 4/alg NCs decreases by increasing the pH value. © 2012 Elsevier Ltd. All rights reserved.
Synthesis, growth mechanism and characterization of single crystalline λ-Fe 2o 3 Spherical Nanoparticles
(2012) Manish Srivastava; Jay Singh; Madhu Yashpal; Animesh K. Ojha
In the present report, we proposed a simple and efficient method for synthesizing single crystalline-Fe 2o 3 spherical nanoparticles array into hexagonal dipyramid (HGDP) hierarchical structures using urea as a surface-active agent to control the growth and nucleation of the iron species. Growth mechanisms for the formation of HGDP hierarchical structures have been also proposed. Single crystalline feature, structural morphology and size of the nanoparticles were investigated by X-ray diffraction (XRD), Scanning and Transmission electron microscopy (SEM). The spectroscopic techniques such as; FT-IR, UV-VIS absorption and Raman spectroscopy were used to investigate optical response of the synthesized nanoparticles. Optical energy band gap was calculated to be 2.57 eV and 2.21 eV corresponding to direct and indirect transitions, respectively. The magnetic properties of the single crystalline nanoparticle were also investigated by Vibrating sample magnetometer (VSM) and found that they are weak ferromagnetic in nature. The values of saturation magnetization, remanent magnetization and coercivity were found to be 0.5925 emu/g and 0.1642 emu/g and 0.1650 Oe, respectively. Copyright © 2012 American Scientific Publishers.
Toxic effects of repeated oral exposure of silver nanoparticles on small intestine mucosa of mice
(2013) Brigesh Shahare; Madhu Yashpal; Gajendra Singh
As the use of silver nanoparticles (AgNPs) is increasing fast in industry, food, medicines, etc., exposure to AgNPs is increasing in quantity day by day. So, it is imperative to know the adverse effects of AgNPs in man. In this study, we selected mice as an animal model and observed the effect of AgNPs on small intestinal mucosa. AgNPs ranging from 3 to 20nm were administered orally at a dose of 5, 10, 15 and 20mg/kg body weight to the Swiss-albino male mice for 21d. There was a significant decrease (p<0.05) in the body weight of mice in all the AgNPs-treated groups. Mice treated at a dose of 10mg/kg showed the maximum weight loss. Effects were noted by using light microscopy as well as transmission electron microscopy. It was found that AgNPs damage the epithelial cell microvilli as well as intestinal glands. It may be hypothesized that loss of microvilli reduced absorptive capacity of intestinal epithelium and hence weight loss. © 2013 Informa UK Ltd All rights reserved.