Showing papers by "Jawaharlal Nehru University published in 1994"
TL;DR: This dose, which has been set as the safe limit for general public exposure by the Non-Ionizing Radiation Committee of the International Radiation Protection Association, may imply a need for (re)evaluation of the mutagenic potential of microwaves at the prescribedsafe limit for the personnel and people who are being exposed.
Abstract: The potential mutagenic effect of low power microwave at the DNA sequence level in the mouse genome was evaluated by direct DNA analysis. Animals were exposed to microwave at a power density of 1 mW/cm2 for 2 h/day at a frequency of 2.45 GHz over a period of 120, 150 and 200 days. HinfI digested DNA samples from testis and brain of control and exposed animals were hybridized with a synthetic oligo probe (OAT 36) comprising nine repeats of 5'-GACA-3'. As compared to control animals, band patterns in exposed animals were found to be distinctly altered in the range of 7-8 kb which was also substantiated by densitometric analysis. Though the mechanism of this rearrangement is not yet clear, the results obtained at the present dose are of significance. This dose, which has been set as the safe limit for general public exposure by the Non-Ionizing Radiation Committee of the International Radiation Protection Association, may imply a need for (re)evaluation of the mutagenic potential of microwaves at the prescribed safe limit for the personnel and people who are being exposed.
145 citations
TL;DR: It was evident that the chronic co-administration of coffee was effective in significantly reducing the frequencies of single and twin spots induced by CPH, DEN, MMC and URE but not PRO.
Abstract: The somatic mutation and recombination test (SMART) in Drosophila melanogaster was carried out to investigate whether or not coffee can modulate the genotoxicity of the well-established mutagenic/carcinogenic chemicals cyclophosphamide (CPH), diethylnitrosamine (DEN), mitomycin C (MMC), procarbazine (PRO) and urethane (URE). For this purpose, 3-day-old larvae, trans-heterozygous for the wing hair markers mwh (multiple wing hairs) and flr3 (flare3), were raised on instant medium containing either the genotoxin alone or in combination with instant coffee. From the results obtained, it was evident that the chronic co-administration of coffee was effective in significantly reducing the frequencies of single and twin spots induced by CPH, DEN, MMC and URE but not PRO. The maximum reduction was observed in the frequencies of twin spots (produced by mitotic recombination) after feeding larvae on medium containing coffee in combination with the compounds CPH or URE.
123 citations
TL;DR: The data clearly indicate that sperm hyaluronan binding protein may have a specific role in sperm maturation, motility, and fertilization processes.
Abstract: Hyaluronic acid, a major component of the extracellular matrix, plays an important role in the regulation of different cellular processes, e.g., locomotion, cell-cell interaction during morphogenesis, and differentiation. Distribution of hyaluronic acid with respect to the role of sperm hyaluronidase in sperm penetration and gamete interaction is well established. In order to elucidate this mechanism, in our current study we have identified and demonstrated, for the first time, the presence of a 68-kDa cell surface hyaluronic acid binding glycoprotein (HABP) in spermatozoa of different species (rat, mice, bull, and human) by immunoblot analysis and indirect immunofluorescence using the polyclonal antibodies raised against purified HABP. Furthermore, we were able to demonstrate a differential distribution of 68-kDa HA binding protein on the sperm head, midpiece, and tail of different species. To identify its role in sperm function, we observed its declining pattern during epididymal maturation and also the inhibition of sperm-oolemmal adherence by pretreatment of the sperms with anti-HABP antibodies. We have further observed its in vivo phosphorylation in motile spermatozoa. All our data clearly indicate that sperm hyaluronan binding protein may have a specific role in sperm maturation, motility, and fertilization processes.
104 citations
TL;DR: The distinct role of the intestinal flora in degradation of wood components such as cellulose, hemicellulose and lignin is summarized.
Abstract: In several aspects termites are a fascinating group of insects having attracted the interest of many researchers. They exhibit a complex social behavior and caste differentiation occurring elsewhere only among the hymenoptera. In an enlarged part of the hindgut, the paunch, termites have established a unique symbiotic association with prokaryotic and eukaryotic microorganisms. A similar flora is also found in wood-eating roaches of the genus Cryptocercus. The study of symbiosis between termites and their intestinal microbes is of general interest, because due to this symbiotic interaction termites can feed on complex biopolymers such as wood. Flagellates and bacteria occur in the gut of lower termites, while higher termites possess only bacteria. In particular spirochetes are abundant in the termite gut. Apart from spirochetes and other more common bacteria, actinomycetes, yeasts and fungi have also been isolated from different species of termites. This review summarizes the distinct role of the intestinal flora in degradation of wood components such as cellulose, hemicellulose and lignin.
89 citations
TL;DR: The wet evergreen forest of Nelliampathy in the Western Ghats of Kerala in India is a mixed forest with a high species diversity and basal cover as discussed by the authors, and the mean number of gaps formed in this forest is 1.13 ha−1 y−1 and the turnover rate is 83 years.
Abstract: The wet evergreen forest of Nelliampathy in the Western Ghats of Kerala in India is a mixed forest with a high species diversity and basal cover. In this relatively undisturbed ecosystem, canopy gaps are largely formed through single tree fall, but gaps through branch fall, crown fall, standing dead trees or multiple tree fall also occur. Canopy gap formation is more (over 82% of the total gaps created) during the monsoon season. The mean number of gaps formed in this forest is 1.13 ha−1 y−1 and the turnover rate is 83 years. The majority of the gaps created (over 70%) are of smaller size (≥ 100 m2). In this forest, while some top canopy tree species (those capable of exceeding 25 m in height at maturity) such as Palaquium ellipticum and Mesua nagassarium are well represented in seedling, sapling and mature tree stages, others like Aglaia exstipulata and Mastixia arborea are observed only as saplings and/or mature trees with no seedling populations. The possible reasons for these two types of regeneration behaviour by top canopy tree species in the context of canopy gap size and seasonality in gap formation are discussed.
87 citations
TL;DR: In this paper, the influence of essential oils from naturally occurring plant dietary items such as cardamom, celery seed, cumin seed, coriander, ginger, nutmeg, and zanthoxylum on the activities of hepatic carcinogen-metabolizing enzymes (cytochrome P450, aryl hydrocarbon hydroxylase, and glu-tathione S-transferase) and acid-soluble sulfhydryl level was investigated in Swiss albino mice.
Abstract: The influence of essential oils from naturally occurring plant dietary items such as cardamom, celery seed, cumin seed, coriander, ginger, nutmeg, and zanthoxylum on the activities of hepatic carcinogen‐metabolizing enzymes (cytochrome P450, aryl hydrocarbon hydroxylase, and glu‐tathione S‐transferase) and acid‐soluble sulfhydryl level was investigated in Swiss albino mice. Each oil was fed by gavage at 10 μl/day for 14 days, and then the animals were sacrificed and their hepatic enzyme activities and sulfhydryl levels were evaluated. Only nutmeg and zanthoxylum oils induced cytochrome P450 level significantly (p < 0.05), whereas cardamom oil caused a significant reduction in its activity (p < 0.05). Furthermore, aryl hydrocarbon hydroxylase activity was significantly elevated only by treatment with ginger oil (p < 0.01), whereas nutmeg oil caused a significant reduction in its activity (p < 0.01). The remaining oils did not significantly alter the level of cytochrome P450 and aryl hydrocarbon hy...
68 citations
TL;DR: The extrachromsomal ribosomal DNA (rDNA) circle of the human protozoan parasite Entamoeba histolytica HM-1:IMSS is sequenced and the complete sequence organisation of the 24.5-kb molecule is presented.
60 citations
TL;DR: The results suggest the presence of a signal transduction system in C. albicans similar to that of S. cerevisiae a or alpha ste12 mutants, and the amino acid sequence of the NH2-terminal 215 residues of Acprp is highly similar to the DNA binding domain of Ste12p of Saccharomyces Cerevisiae.
59 citations
TL;DR: Essential oils from common spices were tested for their ability to suppress the formation of DNA adducts by aflatoxin B1 in vitro in a microsomal enzyme-mediated reaction and all oils were found to inhibit adduct formation very significantly and in a dose-dependent manner.
Abstract: Essential oils from common spices such as nutmeg, ginger, cardamom, celery, xanthoxylum, black pepper, cumin, and coriander were tested for their ability to suppress the formation of DNA adducts by aflatoxin B1 in vitro in a microsomal enzyme-mediated reaction. All oils were found to inhibit adduct formation very significantly and in a dose-dependent manner. The adduct formation appeared to be modulated through the action on microsomal enzymes, because an effective inhibition on the formation of activated metabolite was observed with each oil. The enzymatic modulation is perhaps due to the chemical constituents of the oils, and this could form a basis for their potential anticarcinogenic roles.
58 citations
TL;DR: Optimal cellulase production (0.8 mg/ml) along with the best utilization of substrate was observed with mixed cultivation of two strains simultaneously.
52 citations
TL;DR: Chlorophyllin was evaluated in the mouse bone marrow micronucleus test for its possible protective effects against chromosomal damage induced by gamma-radiation, cyclophosphamide, N-nitroso-N-ethylurea and urethane and there was no indication of a dose response for the in vivo anticlastogenic effects.
Abstract: Chlorophyllin was evaluated in the mouse bone marrow micronucleus test for its possible protective effects against chromosomal damage induced by gamma-radiation, cyclophosphamide, N-nitroso-N-ethylurea and urethane. Three doses of chlorophyllin (50, 100 and 200 mg/kg, b.w.) were orally administered to mice 2 h before exposure to the clastogens under investigation. The results obtained demonstrated that chlorophyllin can significantly reduce the incidence of micronucleated polychromatic erythrocytes induced by gamma-radiation (1.15 Gy) and all the three chemical clastogens. However with the exception of cyclophosphamide there was no indication of a dose response for the in vivo anticlastogenic effects of chlorophyllin.
TL;DR: In this paper, the authors studied the impact of gap age on the performance of ground vegetation in the Western Ghats in India and found that the fractional annual turnover rates of elements of the ground vegetation and the soil were higher in 1-year-old gaps than in undisturbed sites, owing to the release of these nutrients from leaf litter and wood debris which were deposited in larger quantities within the gap itself.
TL;DR: A survey of traffic noise in the city of Delhi was carried out in order to examine the nature and levels of noise inside various types of vehicle as discussed by the authors, and it was found that noise levels in auto-rickshaws are the highest, followed by trucks, buses and cars.
TL;DR: Upon exposure of the leaves to light, the dark-accumulated Pchlide was efficiently phototransformed to chorophyllide (Chlide), even on the 7th d of dark incubation, demonstrating that the activity of PchLide reductase, one of the late enzymes of the Chl biosynthetic pathway, is not substantially affected during senescence.
Abstract: The chlorophyll (Chl) biosynthetic reactions were monitored during senescence of dark-incubated excised barley (Hordeum vulgare L. cv IB 65) leaves floated in double-distilled water or kinetin solution. Kinetin abolished the degradation of Chl but failed to check the net degradation of protochlorophyllide (Pchlide), suggesting that different sets of enzymes, i.e. kinetin sensitive and insensitive, are responsible for the degradation of Chl and Pchlide, respectively. Upon exposure of the leaves to light, the dark-accumulated Pchlide was efficiently phototransformed to chorophyllide (Chlide), even on the 7th d of dark incubation, demonstrating that the activity of Pchlide reductase, one of the late enzymes of the Chl biosynthetic pathway, is not substantially affected during senescence. The senescing leaves continued to synthesize Pchlide and Chlide until the 7th d, although at a reduced rate (20% of the 1st d). The decline of the rate of synthesis of Pchlide and Chlide is due to the loss of activity of two early enzymes of the Chl biosynthetic pathway, i.e. 5-aminolevulinic acid dehydratase and porphobilinogen deaminase. Kinetin substantially checked the loss of activity of these two enzymes.
TL;DR: In this article, a cross-sectional study of 306 districts of India, using a composite index of development, was conducted separately for males and females on the one hand, and the rural and urban segments on the other.
Abstract: This article analyses forces which influence the degree of participation of population in economic activity in a developing economy. In the first stage the relationship between economic development and work participation is examined. The core of the analysis is based on a cross‐sectional study of 306 districts of India, using a composite index of development. The entire analysis is conducted separately for males and females on the one hand, and the rural and urban segments on the other. The oft‐referred‐to inverse relationship between female work participation and economic development emerges to be true in initial stages of development in the rural segment, but not so in the case of the urban segment. In the second stage the role of key socioeconomic and demographic factors, in addition to that of development, has been investigated using a recursive multi‐equation regression model. Finally, keeping in mind the crucial role of education in this context, work participation is analysed in terms of ten disagg...
TL;DR: In this article, water and sediment samples collected from the Gomti River, a tributary of the Ganges River system, during the post-monsoon season have been analyzed to estimate major elemental chemistry.
Abstract: Water and sediment samples collected from the Gomti River, a tributary of the Ganges River system, during the postmonsoon season have been analyzed to estimate major elemental chemistry. Water chemistry of the River Gomti shows almost monotonous spatial distribution of various chemical species, especially because of uniform presence of alluvium Dun gravels throughout the basin. The river annually transports 0.34×106 tonnes of total suspended material (TSM) and 3.0×106 tonnes of total dissolved solids (TDS), 69 percent of which is accounted for by bicarbonate ions only. Samples collected downstream of the city of Lucknow show the influence of anthropogenic loadings for a considerable distance in the river water. Na+, Cl−, and SO4
2− concentrations build up downstream. The bed sediment chemistry is dominated by Si (36 percent), reflecting a high percentage of detrital quartz, which makes up about 74 percent of the mineralogy of the bed sediments in the River Gomti. The average Kjeldahl nitrogen concentration (234 μg/g) indicates indirectly the amount of organic matter in the sediments. The Hg concentration in sediments has been found to be higher (average 904 ppb) than the background value. The suspended sediments are well sorted, very finely skewed, and extremely leptokurtic, indicating a low energy condition of flow in the Gomti River. The influence of chemical loads in the Gomti has been found to be small or nonexistent on the Ganges River, perhaps because the water discharge of the Gomti (1.57 percent) to the Ganges is quite low.
TL;DR: Analyse des relations commerciales entre l'Inde Moghole and l'Asie Centrale (Ouzbechistan), du 16eme au 18eme siecle, a partir de l'etude des mouvements de biens, des commercants and de leurs relations avec leur etat, and des consequences of ces flux commerciaux sur l'economie and la politique au nord de l´Inde as discussed by the authors.
Abstract: Analyse des relations commerciales entre l'Inde Moghole et l'Asie Centrale (Ouzbechistan), du 16eme au 18eme siecle, a partir de l'etude des mouvements de biens, des commercants et de leurs relations avec leur etat, et des consequences de ces flux commerciaux sur l'economie et la politique au nord de l'Inde
TL;DR: The chemical composition of Cauvery river water is dominated by Na and HCO 3, indicating the influence of airborne salts with oceanic affinities in the downstream region of the river as discussed by the authors.
TL;DR: In this paper, the authors discussed the role of Hindutva politics and the farmers' movement in Uttar Pradesh, and the shifting ground between the two groups was discussed. The Journal of Peasant Studies: Vol. 21, No. 7, New Farmers' Movements in India, pp 165-194.
Abstract: (1994). Shifting ground: Hindutva politics and the farmers’ movement in Uttar Pradesh. The Journal of Peasant Studies: Vol. 21, New Farmers' Movements in India, pp. 165-194.
TL;DR: In this paper, the pH, major cations and anions of the samples were determined and the ionic balance was calculated and two consecutive months (August and September) during monsoon were found to be acidic.
TL;DR: The characteristics of the fucoxanthin chlorophylla/c proteins, the mode of transport of these proteins into plastids, the arrangement of the genes encoding these proteins, and efforts to utilize these genes to develop a DNA transformation system for diatoms are focused on.
Abstract: In chromophytic algae the major light-harvesting complex is the fucoxanthin chlorophylla/c protein complex. Recently, we have cloned several highly related cDNA and genomic sequences encoding the fucoxanthin chlorophylla/c proteins from the diatomPhaeodactylum tricornutum. These genes are clustered on the nuclear genome. The sequences of the fucoxanthin chlorophylla/c proteins as deduced from the gene sequences have some similarity to the chlorophylla/b proteins associated with light-harvesting complexes of higher plants and green algae. Like the chlorophylla/b proteins of higher plants, the fucoxanthin chlorophylla/c proteins are synthesized as higher-molecular weight precursors in the cytoplasm of the cell and are transported into the plastids. However, the mode of transport into diatom plastids is very different from the mechanism involved in transporting proteins into the chloroplasts of higher plants and green algae. We focus here on the characteristics of the fucoxanthin chlorophylla/c proteins, the mode of transport of these proteins into plastids, the arrangement of the genes encoding these proteins, and efforts to utilize these genes to develop a DNA transformation system for diatoms.
TL;DR: Results indicate that one of the initial events in phytochrome‐mediated enzyme stimulation could be through the generation of ‘signals’ from the turnover of the phosphoinositide cycle.
TL;DR: The results indicate that the activity of GI increased with an increase in the age of mice up to 12-14 months depending on the type of the tissue, thereafter it decreased progressively in the old animals, and may be related to the decreased proliferative capacity of these organs.
TL;DR: The results suggest that phytochrome may be acting through calcium along with messengers like diacylglycerol, generated through the phosphoinositide (PI) cycle to stimulate the induction of NR.
Abstract: A lag phase of 30 min for phytochrome-mediated stimulation in the induction of nitrate reductase (NR) in etiolated leaves of Zea mays var. 'Ganga 5', was eliminated by a 2 h pre-irradiation with red light, supplied in the absence of nitrate. Earlier, photoreversibility of NR activity was found to be lost completely by 2 h and a transmitter with a life span of 12 h was proposed to mediate the phytochrome effect on NR (Sharma and Sopory, 1984). Low temperature (0°C) treatment prevented the loss of the photoreversibility. Almost complete photoreversibility was observed after 2 h, suggesting that the formation of the transmitter requires active metabolism. Tungstate, given 2 h after red light treatment, inhibited the increase in the enzyme activity by red light, suggesting that the transmitter is not inactive NR itself, which becomes activated by nitrate. Analysis of steady-state levels of the NR transcript revealed that NR mRNA is not induced in response to Pfr formation in the absence of nitrate treatment, suggesting that it could not be the transmitter mediating the phytochrome effect on NR activity. Red light was found to increase the uptake of 45Ca2+ by isolated maize protoplasts. When supplied exogen-ously calcium increased NR activity by 48% of that obtained by red light irradiation. However, exogenous addition of phorbol myristate acetate (PMA), an activator of protein kinase C, was found to increase the NR transcript level to the same extent obtained after 5 min of red light irradiation. The results suggest that phytochrome may be acting through calcium along with messengers like diacylglycerol, generated through the phosphoinositide (PI) cycle to stimulate the induction of NR.
TL;DR: The proposed analytical framework suggests that both international trade and migration may contribute to, but cannot lead to, a development process that brings about a migration transition in surplus labor economies.
Abstract: This article presents a theoretical analysis of how the processes of industrialization and development interact with international trade in goods or services to influence a countrys turning point from labor exporter to labor importer. It is concluded that trade in goods complements capital movements but substitutes for labor movements whereas trade in services and labor movements complement each other. The proposed analytical framework suggests that both international trade and migration may contribute to but cannot lead to a development process that brings about a migration transition in surplus labor economies. (EXCERPT)
TL;DR: ACPR from Candida albicans encodes a protein antigenically related to the secretory acid proteinase of this yeast that is highly similar to the amino terminal, DNA-binding domain of STE12 of Saccharomyces cerevisiae, which is involved in mating of haploids and in pseudohyphae formation in diploids.
TL;DR: The effect of decoherence is analysed for a free particle, interacting with an environment via a dissipative coupling, finding that the density matrix becomes completely diagonal in momentum with time while the position space density matrix remains nonlocal.
Abstract: The effect of decoherence is analyzed for a free particle interacting with an environment via dissipative coupling. The interaction between the particle and the environment occurs by a coupling of the position operator of the particle with the environmental degrees of freedom. By examining the exact solution of the density-matrix equation, one finds that the density matrix becomes completely diagonal in momentum with time, while the position space density matrix remains nonlocal. This establishes the momentum basis as the emergent ``preferred basis'' selected by the environment, which is contrary to the general expectation that position should emerge as the preferred basis, since the coupling with the environment is via the position coordinate.
TL;DR: Although the observed replication initiation in the OriA recombinant template is chloroplast-DNA-specific, the mode of replication is different from that observed in vivo with intact ctDNA, however, when the template DNA contains both the Ori a and OriB sequences, the in vitro replication proceeds in the theta mode, the modes of replication usually observed in vitro.
Abstract: A partially purified replicative system of pea chloroplast that replicates recombinant DNAs containing pea chloroplast origin sequences has been characterised. Polymerisation by this system is very fast and insensitive to chain terminators like dideoxynucleotides, arabinosylcytosine 5'-triphosphate, etc. Both strands of template DNA are synthesized and single-stranded DNA templates undergo more than one round of replication. When sequences of either of the two chloroplast origins of replication (OriA or OriB) are used as templates, the replicative intermediates are found to have sigma structures. Electron microscopic analysis of the sigma structures restricted with various enzymes reveals that the initiation site of in vitro replication maps near the displacement-loop regions where replication initiates also in vivo. Although the observed replication initiation in the OriA recombinant template is chloroplast-DNA-specific, the mode of replication is different from that observed in vivo with intact ctDNA. However, when the template DNA contains both the OriA and OriB sequences, the in vitro replication proceeds in the theta mode, the mode of replication usually observed in vivo.
TL;DR: In this paper, the authors argue that religious nationalism and democratic polity cannot coexist harmoniously, particularly in a society characterized by religious diversity, and that the claim to nationality/nationhood can succeed only if the religions under reference press into service a domain assumption, an ideological tenet and two strategies, all of which are logically linked.
Abstract: It is argued in this article that religious nationalism and democracy are antithetical in their orientation. There are severalreasons for this. First, nationhood based on religion assumes a necessary conterminality between religion and territory. While in the case of proselytizing religions (e.g., Buddhism, Christianity and Islam) such an assumption is patently contradictory, even in the case of nonproselytizing religions (e.g., Hinduism, Judaism) religion-territory linkages are often blurred through conquest, colonization, and migration. Second, once territorialization becomes the domain assumption of a religion, a process of homogenization of the culture of the territory and the consequent hegemonization by the dominant religious collectivity often becomes its necessary ideological tenet. Third, this ideology calls for the praxis of "communalization" of politics and "relativization" of culture, all of which have disastrous consequences for a democratic polity. The argument is pursued with special reference to India. In this article I propose to argue that religious nationalism and democratic polity cannot co-exist harmoniously, particularly in a society characterized by religious diversity. Yet, some religious collectivities advance the claim that they are "nations." The claim to nationality/nationhood can succeed only if the religions under reference press into service a domain assumption, an ideological tenet and two strategies, all of which are logically linked. The domain assumption is that there is a conterminality between religion and territory; the ideological tenet is homogenization of the society by imposing the life-style associated with the religious collectivity asserting or aspiring to nationhood - that is, establishing hegemony over the dominated religious collectivities. The strategies pursued to achieve the goal are communalization and relativization, which are logical corollaries of territorialization and homogenization, respectively - all of which are antithetical to the ethos of democracy. My concern in this article is with the articulations of religious nationalisms in India. I shall desist from the temptation of tracing the trajectories of these religious nationalisms - Hindu, Muslim, and Sikh - because they are well known and well documented. Instead, I will endeavor to show that the assump
TL;DR: Experiments to test the possibility that these antileishmanial agents exert their inhibitory effect by blocking polyamine biosynthesis suggest that decrease in ornithine decarboxylase activity and the inhibition of polyamine levels could be a mechanism of inhibition of promastigote growth by BHA and RA.