Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Morphol ; 283(7): 956-972, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35621718

RESUMO

Earthworms inhabit different strata of moist soil. Epigeic and endogeic earthworms prefer superficial and inner stratum of soil respectively, whereas, semiaquatic species are distributed around hydrated soil near ponds and lakes. Coelomocytes, the chief immunoeffector cells of coelomic origin, perform diverse physiological functions like phagocytosis, maintenance of cellular homeostasis, and acid-base balance of coelomic fluid, graft rejection, elicitation of cytotoxic, and oxidative responses under the challenges of pathogens and toxins. The present study aims to analyze selected morphological and functional parameters in three differentially adapted Indian earthworms of nonsimilar habitats. Coelomocytes of Glyphidrilus tuberosus (Stephenson, 1916) (semiaquatic), Perionyx excavatus (Perrier, 1872) (epigeic), and Eutyphoeus orientalis (Beddard, 1883) (endogeic) were isolated for morphological and morphometric analyses and subjected to determination of phagocytic, oxidative, and cytotoxic responses. Activities of phenoloxidase, pro, and antioxidant enzymes, and autofluorescence were determined in the extruded coelomocytes of earthworms of three contrasting habitats. The differential result may be correlated with species-specific responses and variation in habitat preference and related adaptation.


Assuntos
Oligoquetos , Animais , Ecótipo , Estresse Oxidativo , Fagocitose , Solo
2.
Artigo em Inglês | MEDLINE | ID: mdl-35182717

RESUMO

The current study is aimed to assess the ecotoxicological effects of toxic metals and seasonal shift of the physicochemical characteristics of soil in an endogeic earthworm Metaphire posthuma of industrially contaminated soil of Calcutta leather complex. The accumulation of cadmium, chromium, lead and mercury was quantitated in whole earthworms and coelomocytes. The accumulation of metals was derived to be high in the coelomocytes than whole earthworms. Morphofunctional shift in coelomocytes indicated a high level of metal toxicity in soil inhabitants. The shift in differential coelomocyte count and cellular damage including intense cytoplasmic vacuolation and membrane blebbing of coelomocytes of M. posthuma of contaminated soil were suggestive to a state of immunocompromisation in the same species. Shift in the generation of nitric oxide and activity of inducible nitric oxide synthase indicated a possible immunosuppression in earthworm. Depletion in the acetylcholinesterase activity of coelomocytes indicated neurotoxicity of metals leached from the dumped wastes in Calcutta leather complex. Integrated biomarker response based analysis was carried out to assess the biomarker potential of experimental endpoints of M. posthuma to monitor metal toxicity in soil.


Assuntos
Metais , Oligoquetos , Poluentes do Solo , Acetilcolinesterase , Animais , Biomarcadores , Índia , Metais/análise , Metais/toxicidade , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
3.
Phys Fluids (1994) ; 32(11): 111903, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33244213

RESUMO

The transport and deposition of micrometer-sized particles in the lung is the primary mechanism for the spread of aerosol borne diseases such as corona virus disease-19 (COVID-19). Considering the current situation, modeling the transport and deposition of drops in human lung bronchioles is of utmost importance to determine their consequences on human health. The current study reports experimental observations on deposition in micro-capillaries, representing distal lung bronchioles, over a wide range of Re that imitates the particle dynamics in the entire lung. The experiment investigated deposition in tubes of diameter ranging from 0.3 mm to 2 mm and over a wide range of Reynolds number (10-2 ⩽ Re ⩽ 103). The range of the tube diameter and Re used in this study is motivated by the dimensions of lung airways and typical breathing flow rates. The aerosol fluid was loaded with boron doped carbon quantum dots as fluorophores. An aerosol plume was generated from this mixture fluid using an ultrasonic nebulizer, producing droplets with 6.5 µm as a mean diameter and over a narrow distribution of sizes. The amount of aerosol deposited on the tube walls was measured using a spectrofluorometer. The experimental results show that dimensionless deposition (δ) varies inversely with the bronchiole aspect ratio ( L ¯ ), with the effect of the Reynolds number (Re) being significant only at low L ¯ . δ also increased with increasing dimensionless bronchiole diameter ( D ¯ ), but it is invariant with the particle size based Reynolds number. We show that δ L ¯ ∼ R e - 2 for 10-2 ⩽ Re ⩽ 1, which is typical of a diffusion dominated regime. For Re ⩾ 1, in the impaction dominated regime, δ L ¯ is shown to be independent of Re. We also show a crossover regime where sedimentation becomes important. The experimental results conclude that lower breathing frequency and higher breath hold time could significantly increase the chances of getting infected with COVID-19 in crowded places.

4.
Interdiscip Toxicol ; 11(2): 155-168, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31719787

RESUMO

Washing soda has been identified as a precarious contaminant of the freshwater ponds and lakes, the natural habitat of Eunapius carteri. Treatment of sublethal concentrations of washing soda for 384 hours exhibited a significant decrease in the densities of blast like cells, small and large amoebocytes. The percentage occurrence of granular cells and archaeocytes yielded a marked increase against the experimental concentrations of washing soda. Washing soda mediated alterations in the differential cell densities of E. carteri indicative of a state of physiological stress and an undesirable shift in the cellular homeostasis of the organism distributed in polluted environment. Experimental exposure of washing soda yielded a significant increase in the cellular dimensions of large amoebocytes and archaeocytes. Prolonged treatment with washing soda presented a gross reduction in nonself surface adhesion efficacy of E. carteri cells. Experimental concentrations of washing soda resulted in a dose dependent increment in the frequencies of binucleation and micronucleation in the cells of E. carteri. The data were indicative of a high level of genotoxicity of washing soda in E. carteri. The present investigation provides an important information base in understanding the toxin induced chemical stress on the archaic immune defense of a primitive urmetazoa.

5.
Ecotoxicol Environ Saf ; 148: 620-631, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29128823

RESUMO

Copper oxide nanoparticles and copper sulfate are established contaminants of water and soil. Metaphire posthuma is a common variety of earthworm distributed in moist soil of Indian subcontinent. Comparative toxicity of copper nanoparticles and copper sulfate were investigated with reference to selected immune associated parameters of earthworm. Total count, phagocytic response, generation of cytotoxic molecules (superoxide anion, nitric oxide), activities of enzymes like phenoloxidase, superoxide dismutase, catalase, acid phosphatase, alkaline phosphatase and total protein of coelomocytes were estimated under the exposures of 100, 500, 1000mg of copper oxide nanoparticles and copper sulfate per kg of soil for 7 and 14 d. A significant decrease in the total coelomocyte count were recorded with maximum depletion as 15.45 ± 2.2 and 12.5 ± 2 × 104 cells/ml under the treatment of 1000mg/kg of copper nanoparticles and copper sulfate for 14 d respectively. A significant decrease in generation of nitric oxide and activity of phenoloxidase were recorded upon exposure of both toxins for 7 and 14 d indicating possible decline in cytotoxic status of the organism. A maximum inhibition of superoxide dismutase activity was recorded as 0.083 ± 0.0039 and 0.055 ± 0.0057 unit/mg protein/minute against 1000mg/kg of copper nanoparticles and copper sulfate treatment for 14 d respectively. Activities of catalase and alkaline phosphatase were inhibited by all experimental concentrations of both toxins in the coelomocytes of earthworm. These toxins were recorded to be modifiers of the major immune associated parameters of M. posthuma. Unrestricted contamination of soil by sulfate and oxide nanoparticles of copper may lead to an undesirable shift in the innate immunological status of earthworm leading to a condition of immune compromisation and shrinkage in population density of this species in its natural habitat. This article is the first time report of immunological toxicity of nanoparticles and sulfate salt of copper in M.posthuma inhabiting the soil of India, an agriculture based country.


Assuntos
Sulfato de Cobre/toxicidade , Cobre/toxicidade , Nanopartículas/toxicidade , Oligoquetos/fisiologia , Poluentes do Solo/toxicidade , Agricultura , Animais , Ecossistema , Poluição Ambiental , Índia , Monofenol Mono-Oxigenase/metabolismo , Óxido Nítrico/metabolismo , Solo/química , Superóxidos/metabolismo
6.
Phys Chem Chem Phys ; 19(10): 7288-7296, 2017 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-28239716

RESUMO

Bathochromic and hypsochromic shifts in the photo-luminescent spectra of doped and functionalized carbon nano-dots (CDs) arise due to the complex interaction between CDs and the solvent molecules around them. Nitrogen-functionalized carbon nano-dots (N-CDs) were synthesized from citric acid and urea using microwave assisted hydrothermal methods. Optical studies (absorption and photoluminescence) from the as-synthesized N-CDs were carried out in polar protic, aprotic and non-polar solvents. When excited at 355 nm, blue photoluminescence (PL) was observed from the N-CDs dispersed in polar aprotic solvents while green emission was observed in polar protic solvents. In addition to the general solvent effect, the analysis of the luminescence spectra in protic solvents suggests that hydrogen bonding plays a crucial role in regulating the photophysical characteristics of the system. Temperature dependent PL studies and time correlated single photon counting experiments in various solvent dispersions of N-CDs support the role of hydrogen bonding. This indicates that these results depend on the specific interactions observed from the N-CDs and can be thought of as the primary driving force which is then followed by solvent properties like dipole moments. Both the Lippert-Mataga model and Kamlet-Taft parameters were used to support the photophysical properties observed from N-CDs.

7.
J Therm Biol ; 59: 1-12, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27264881

RESUMO

Eunapius carteri, a freshwater sponge of India, inhabits the ponds and lakes and experiences variations of temperature and pH of water throughout the year. Sponges bear evolutionary and ecological importance with limited information on their immunological attribute and adaptational resilience in a changing environment. This paper reports temperature and pH specific responses of immune related parameters in sponge maintained in the experimental conditions of laboratory. Innate immunological parameters like phagocytosis and generation of cytotoxic molecules like superoxide anion, nitric oxide and phenoloxidase activity were estimated in E. carteri at different environmentally realistic water temperatures (10, 20, 30 and 40°C) and pH (6.4, 7.4 and 8.4). Phagocytosis and cytotoxicity are established as important immune parameters of invertebrates. Calalase, an antioxidant enzyme and phosphatases are involved in pathogen destruction and are considered as components of innate immunity. Activities of catalase, acid and alkaline phosphatases were estimated in E. carteri at different thermal regimes and pH. Modulation of phagocytic and cytotoxic responses and the activities of catalase and phosphatases at different water temperatures and pH indicated temperature and pH specific immunological status of E. carteri. Present investigation deals with the effects of selected hydrological parameters on the fundamental immune related parameters in sponge indicating its adaptational plasticity. Immunological resilience of this species in the face of variation of water temperature and pH is thought to be a special adaptive feature of sponge, a reported "living fossil".


Assuntos
Água Doce/química , Poríferos/imunologia , Animais , Concentração de Íons de Hidrogênio , Imunomodulação , Monofenol Mono-Oxigenase/imunologia , Óxido Nítrico/imunologia , Fagocitose , Poríferos/enzimologia , Superóxidos/imunologia , Temperatura
8.
Artigo em Inglês | MEDLINE | ID: mdl-27178357

RESUMO

Washing soda, chemically identified as anhydrous sodium carbonate, is a popular cleaning agent among the rural and urban populations of India which often contaminates the freshwater ponds and lakes, the natural habitat of sponge Eunapius carteri. Present investigation deals with estimation of cellular aggregation, generation of ROS and activities of antioxidant enzymes, lysozyme and acetylcholinesterase in the cells of E. carteri under the environmentally realistic concentrations of washing soda. Prolonged treatment of washing soda inhibited the degree of cellular aggregation. Experimental exposure of 8 and 16mg/l of sodium carbonate for 48h elevated the physiological level of reactive oxygen species (ROS) generation in the agranulocytes, semigranulocytes and granulocytes of E. carteri, whereas, treatment of 192h inhibited the ROS generation in three cellular morphotypes. Activities of superoxide dismutase, catalase and glutathione-S-transferase were recorded to be inhibited under prolonged exposure of washing soda. Washing soda mediated inhibition of ROS generation and depletion in the activities of antioxidant enzymes were indicative to an undesirable shift in cytotoxic status and antioxidative defense in E. carteri. Inhibition in the activity of lysozyme under the treatment of sodium carbonate was suggestive to a severe impairment of the innate immunological efficiency of E. carteri distributed in the washing soda contaminated habitat. Washing soda mediated inhibition in the activity of acetylcholinesterase indicated its neurotoxicity in E. carteri. Washing soda, a reported environmental contaminant, affected adversely the immunophysiological status of E. carteri with reference to cellular aggregation, oxidative stress, antioxidative defense, lysozyme and acetylcholinesterase activity.


Assuntos
Acetilcolinesterase/metabolismo , Antioxidantes/metabolismo , Carbonatos/toxicidade , Muramidase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Poríferos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Agregação Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Monitoramento Ambiental/métodos , Água Doce , Glutationa Transferase/metabolismo , Índia , Poríferos/enzimologia , Poríferos/imunologia , Medição de Risco , Superóxido Dismutase/metabolismo , Fatores de Tempo
9.
Ecotoxicol Environ Saf ; 122: 331-42, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26313128

RESUMO

Washing soda is chemically known as sodium carbonate and is a component of laundry detergent. Domestic effluent, drain water and various anthropogenic activities have been identified as major routes of sodium carbonate contamination of the freshwater ecosystem. The freshwater sponge, Eunapius carteri, bears ecological and evolutionary significance and is considered as a bioresource in aquatic ecosystems. The present study involves estimation of morphological damage, lysosomal membrane integrity, activity of phosphatases and apoptosis in the cells of E. carteri under the environmentally realistic concentrations of washing soda. Exposure to washing soda resulted in severe morphological alterations and damages in cells of E. carteri. Fragility and destabilization of lysosomal membranes of E. carteri under the sublethal exposure was indicative to toxin induced physiological stress in sponge. Prolonged exposure to sodium carbonate resulted a reduction in the activity of acid and alkaline phosphatases in the cells of E. carteri. Experimental concentration of 8 mg/l of washing soda for 192 h yielded an increase in the physiological level of cellular apoptosis among the semigranulocytes and granulocytes of E. carteri, which was suggestive to possible shift in apoptosis mediated immunoprotection. The results were indicative of an undesirable shift in the immune status of sponge. Contamination of the freshwater aquifers by washing soda thus poses an alarming ecotoxicological threat to sponges.


Assuntos
Apoptose/efeitos dos fármacos , Carbonatos/toxicidade , Água Doce/química , Membranas Intracelulares/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Poríferos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Monitoramento Ambiental/métodos , Índia , Membranas Intracelulares/metabolismo , Membranas Intracelulares/patologia , Lisossomos/metabolismo , Lisossomos/patologia , Poríferos/metabolismo
10.
Zoology (Jena) ; 118(1): 8-18, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25547566

RESUMO

The freshwater sponge Eunapius carteri (Porifera: Demospongiae: Spongillidae), a resident of Indian freshwater ecosystems, has pharmaceutical and ecological potential, but there is inadequate information on its cellular spectrum and cell-mediated immune responses. Microscopical analysis revealed the existence of eight distinct cellular variants, i.e. blast-like cells, choanocytes, small amoebocytes, granular cells, pinacocytes, large amoebocytes, archaeocytes and sclerocytes. The cells were isolated by density gradient centrifugation and flow cytometry and used for a morphofunctional analysis. We investigated the phagocytic efficiency of E. carteri cells under the challenge of yeast particles in vitro and spectrophotometrically quantified the generation of cytotoxic molecules (superoxide anions and nitric oxide) in different isolated cellular fractions. The two cell separating technologies did not yield any significant differences in the major findings on morphology, phagocytic response and generation of superoxide anions and nitric oxide. Archaeocytes, granular cells and large amoebocytes were identified as chief phagocytes with a high phagocytic potential as recorded by light microscopy. Archaeocytes were the principal generators of superoxide anions, whereas nitric oxide was recorded in the fractions rich in archaeocytes and large amoebocytes. The present investigation thus provides useful information regarding cellular variation, cytotoxic status and innate phagocytic response of the cells of E. carteri, a common but less studied sponge of India.


Assuntos
Fagocitose , Poríferos/citologia , Animais , Separação Celular , Centrifugação com Gradiente de Concentração , Citometria de Fluxo , Água Doce , Imunidade Inata , Índia , Poríferos/imunologia , Leveduras/imunologia
11.
Ecotoxicol Environ Saf ; 113: 112-23, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25497767

RESUMO

The natural habitat of sponge, Eunapius carteri faces an ecotoxicological threat of contamination by washing soda, a common household cleaning agent of India. Washing soda is chemically known as sodium carbonate and is reported to be toxic to aquatic organisms. Domestic effluent, drain water and various human activities in ponds and lakes have been identified as the major routes of washing soda contamination of water. Phagocytosis and generation of cytotoxic molecules are important immunological responses offered by the cells of sponges against environmental toxins and pathogens. Present study involves estimation of phagocytic response and generation of cytotoxic molecules like superoxide anion, nitric oxide and phenoloxidase in E. carteri under the environmentally realistic concentrations of washing soda. Sodium carbonate exposure resulted in a significant decrease in the phagocytic response of sponge cells under 4, 8, 16 mg/l of the toxin for 96h and all experimental concentrations of the toxin for 192h. Washing soda exposure yielded an initial increase in the generation of the superoxide anion and nitric oxide followed by a significant decrease in generation of these cytotoxic agents. Sponge cell generated a high degree of phenoloxidase activity under the experimental exposure of 2, 4, 8, 16 mg/l of sodium carbonate for 96 and 192 h. Washing soda induced alteration of phagocytic and cytotoxic responses of E. carteri was indicative to an undesirable shift in their immune status leading to the possible crises of survival and propagation of sponges in their natural habitat.


Assuntos
Carbonatos/toxicidade , Poríferos/efeitos dos fármacos , Poluentes da Água/toxicidade , Animais , Água Doce , Índia , Monofenol Mono-Oxigenase/metabolismo , Óxido Nítrico/metabolismo , Fagocitose/efeitos dos fármacos , Poríferos/enzimologia , Poríferos/imunologia , Poríferos/metabolismo , Superóxidos/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...