Publications by authors named "Ajay K Mittal"

Triclosan (TCS), an antimicrobial additive in various personal and health care products, has been widely detected in aquatic environment around the world. The present study investigated the impacts of TCS in the gills of the fish, Cyprinus carpio employing histopathological, biochemical, molecular docking and simulation analysis. The 96 h LC value of TCS in C.

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The bacterial fish pathogen Edwardsiella tarda causes heavy stock mortality, severely hampering fish production, resulting in great economic loss to the farming industry. The first biological barriers that confer immune protection against pathogen entry are the fish mucosal surfaces. The present study was undertaken to investigate the influence of E.

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In the present study, the epidermis of the hill stream fish Hara hara has been investigated employing scanning electron microscope, histology, histochemistry and immunofluorescence techniques. The epidermis is characteristically differentiated into plaques separated from each other by deep furrows. In plaques, the epidermis is keratinized.

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Aspirin is one of the emerging pharmaceutical contaminants in the aquatic environment and thus it could impart toxicity to non-target organisms including fish. The present study aims to investigate the biochemical and histopathological alterations in the liver of the fish, Labeo rohita exposed to environmentally relevant concentrations of aspirin (1, 10, and 100 μg/L) for 7, 14, 21, and 28 days. The biochemical investigation revealed a significant (p < 0.

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The effect of aloin on mucosal immune response and disease resistance was elucidated in Labeo rohita infected with the bacterial fish pathogen, Aeromonas hydrophila. Fishes were divided into four groups: (i) control, (ii) vehicle control, (iii) bacteria infected and (iv) bacteria infected and aloin treated. Fish were intraperitoneally injected with A.

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This study was carried out to comprehend the pathogenicity of the bacteria in the epidermis of Labeo rohita inoculated with Aeromonas hydrophila. Alterations in the histopathology of the epidermis were examined using scanning electron microscopy, light microscopy and the localization of iNOS and caspase 3 + ve cells by means of immunohistochemical methods. Skin samples obtained from infected fish at different intervals 2, 4, 6, 8 and 10 days showed significant changes in the cellular components of the epidermis.

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Present study reports significant modifications in surface ultrastructure, histological organization, and histochemical localization of glycoproteins (GPs) in the gills of a hill stream catfish, Hara hara. Punctate microridges on free surface of epithelial cells covering gill arches, gill rakers, gill filaments and secondary lamellae are considered to provide adaptive plasticity to gills in relation to the environment inhabited by fish. Short and stout gill rakers are considered to prevent food particles to pass in opercular chamber along with respiratory current that could damage delicate gill filaments.

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A series of histochemical techniques have been employed to localize alkaline phosphatase, acid phosphatase, non-specific esterase, catalase and peroxidase; and to visualize and characterize glycoprotein (GPs) moieties in the epithelium of gill arch, gill filaments and secondary lamellae of an angler catfish Chaca chaca. The epithelium of gill arch and gill filament shows strong alkaline phosphatase activity in the deeper layer epithelial cells; strong non-specific esterase activities in the outer layer epithelial cells; and weak acid phosphatase activity throughout the epithelium. The activity of these enzymes in the secondary lamellae is weak.

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Cholinesterases are multifunctional enzymes and have been associated with diverse physiological functions in addition to their classical role at synapses. In the present study, cholinesterase (ChE) isozymes have been characterised in mucous secretions and their activity has been localised in the epidermis of Labeo rohita and Cirrhinus mrigala. Zymography using specific substrates and inhibitors revealed the presence of two ChE isozymes-ChE-1 and ChE-2.

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The present study is concerned with the expression and localization of nitric oxide synthase (NOS) isoforms, nNOS, eNOS and iNOS in the epidermis and the gill epithelium of Chaca chaca by means of immunohistochemical techniques. nNOS immunoreactivity was observed in the outer layer epithelial cells of the epidermis, outer epithelium of gill filaments at their distal regions and in between the secondary lamellae. iNOS positive cells were observed at intervals in the epidermis from basal layer to superficial layer, in outer layers of epithelium of the gill filament and in epithelium of the secondary lamellae.

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The present study describes keratinization and mucogenesis in the epidermis of an angler catfish Chaca chaca, using a series of immunochemical, fluorescence and histochemical methods. The epidermis is primarily mucogenic and shows characteristic specialised structures at irregular intervals. These structures are identified keratinized in nature.

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The present work was undertaken with the aim to deduce morphological adaptations in skin of an angler catfish Chaca chaca by means of scanning electron microscopy. The fish is nocturnal, bottom dwelling, sluggish, ambush predator, lives in sand, mud, or soft substrates often buried and camouflaged for protection and to feed. The surface of the epidermis is covered with polygonal epithelial cells, each having surface relief of microridges forming intricate patterns.

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In Labeo rohita exposed to sub-lethal concentrations of an azo dye, Eriochrome black T for 4 days, gills show considerable alterations in the activity of certain metabolic enzymes-alkaline phosphatase, acid phosphatase, carboxylesterase, lactate dehydrogenase, and succinate dehydrogenase; and antioxidant enzymes-catalase and peroxidase. The activities of alkaline phosphatase, acid phosphatase, carboxylesterase, succinate dehydrogenase, catalase, and peroxidase decline significantly. This has been associated with impaired metabolic function of the gills due to azo dye toxicity.

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Enhancement of immune system seems to be the most promising method of preventing fish diseases. Several herbal products have immunostimulant properties, and are environmental friendly, economical and can act against a broad spectrum of pathogens. Present study was designed with an aim to evaluate the role of aloin, extracted from a herb Aloe barbadensis, in the modulation of certain immune parameters in an Indian major carp, Labeo rohita.

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In the present study effect of asiaticoside, on healing of skin wounds in Cirrhinus mrigala is reported. Skin wound, approx. 2mm in diameter was excised using sterile disposable biopsy punch.

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Present scanning electron microscope study, reports healing of excised skin wounds in Cirrhinus mrigala. Healing process of wounds, inflicted on head skin, using biopsy punch was observed at intervals-0 hour (h), 1, 2, 4, 6, 12 h, 1 day (d) 2 and 4 d. Accumulation of mucus in wound region within 1h after infliction of wound has been considered an immediate measure to provide protection to injured skin from microbial invasion and other external environmental hazards.

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Histopathological changes and alterations in the activity of certain metabolic and antioxidant enzymes were analyzed in the head skin of Labeo rohita, exposed to sublethal test concentrations of the azo dye, Eriochrome black T for 4 days, using 24 h renewal bioassay method. Hypertrophied epithelial cells, increased density of mucous goblet cells, and profuse mucous secretion at the surface were considered to protect the skin from toxic impact of the azo dye. Degenerative changes including vacuolization, shrinkage, decrease in dimension, and density of club cells with simultaneous release of their contents in the intercellular spaces were associated to plug them, preventing indiscriminate entry of foreign matter.

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Surface ultrastructure of the gills of the angler catfish Chaca chaca was investigated to unravel the adaptive modifications associated with the feeding ecology of the fish. The fish is often found in mud or in soft substrates where they remain buried both for protection and to feed. Gill rakers present on the gill arch in most fish species are absent in this fish.

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The histological organization and histochemical aspects of the pharyngeal jaw apparatus of the Indian major carp Cirrhinus mrigala are described. The pharyngeal jaw apparatus consists of a lower pharyngeal jaw and a chewing pad. Histochemical analysis reveals that the epithelium covering the lower pharyngeal jaw is mucogenic and is involved in the secretion of different classes of glycoproteins (GPs) including GPs with oxidizable vicinal diols, GPs with O-sulphate esters and GPs with sialic acid residues with and without O-acyl substitution.

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Presence of carboxylesterase (CbE) activity in the skin mucus of Cirrhinus mrigala was investigated. CbE activity in skin mucus showed higher substrate preference for α-naphthyl acetate over p-nitrophenyl acetate. Four CbE isozymes-CbE-1, CbE-2, CbE-3, and CbE-4 were observed in skin mucus during zymography.

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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.

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The presence of cholinesterase (ChE) activity in skin mucus of three carps, Cirrhinus mrigala, Labeo rohita, and Catla catla and its applicability as biomarker of the organophosphorus insecticide exposure were investigated. Biochemical characterization, using specific substrates and inhibitors, indicated that measured esterase activity in skin mucus was mainly owing to ChEs. Significant difference in the proportion of acetylcholinesterase and butyrylcholinesterase activities was observed in skin mucus of three carps.

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The innate immune system of fish is considered first line of defense against a broad spectrum of pathogens. Being a component of innate immunity and lying at the interface between fish and the aqueous environment, skin mucus plays a frontier role in protecting fish from infections. In the present study, skin mucus of Cirrhinus mrigala, Labeo rohita, Catla catla, Rita rita and Channa punctata, inhabiting different ecological niches, was analyzed to characterize potential innate immune factors such as lysozyme, proteases, phosphatases, esterase and sialic acid.

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In this study, healing of cutaneous wounds in Labeo rohita using scanning electron microscope is reported. Wound area could be divided into three regions. Immediately after infliction of wound, edges retract exposing underlying tissues in wound gap (Region I).

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Glycoproteins were analyzed by a range of histochemical methods in the epithelium of gills of Cirrhinus mrigala, a valuable food fish of great economic importance cultured extensively in India. The gills consist of gill arches, gill rakers, gill filaments and secondary lamellae. Major components of the epithelium of gill arches and gill rakers are epithelial cells, mucous goblet cells, rodlet cells, lymphocytes, eosinophilic granular cells and taste buds.

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