Showing papers by "Jawaharlal Nehru University published in 1991"
TL;DR: A recombinant, polyhedrin-positive Autographa californica NPV is constructed that is orally infectious and expresses an insect-selective toxin (AalT) isolated from the scorpion Androctonus australis under the control of the p10 promoter.
Abstract: Recombinant nuclear polyhedrosis viruses (NPVs) expressing insect-selective toxins, hormones, or enzymes could enhance their insecticidal properties. We have constructed a recombinant, polyhedrin-positive Autographa californica NPV (AcNPV) that is orally infectious and expresses an insect-selective toxin (AalT), isolated from the scorpion Androctonus australis, under the control of the p10 promoter. Bioassays with the recombinant baculovirus on 2nd instar larvae of Heliothis virescens demonstrated a significant decrease in the time to kill (LT50 88.0 hours) compared to wild-type AcNPV (LT50 125 hours). Production of AalT was confirmed by western blot analysis of larval hemolymph from infected H. virescens, and bioassays with larvae of Sarcophaga falculata.
231 citations
TL;DR: In this paper, it was shown that Cd 2+ ions (30-120 fiu) induced a significant decrease in photoreduction of both photosystem II and photosystem I. The extent of the decrease in PS II activity was much greater than that in the PS I activity.
Abstract: 2+ ions for 24 h in dark, and after this treatment the plants were grown in the light until the primary leaves were fully developed. Cd 2+ ions (30-120 fiu) induced a significant decrease in activities of both photosystem II and photosystem I. The extent of the decrease in PS II activity was much greater than that in the PS I activity. Analysis of changes in the fluorescence yield of chlorophyll a also indicated that Cd 2+ ions drastically affect the photochemistry of photosystem II. Cd 2+ ions induced decrease in the rates of photoreduction of 2,6-dichlorophenol indophenol even in the presence of the exogenous electron donor, hydroxylamine, both in Tris-treated and untreated chloroplasts. This result suggests that the site of inhibition is near the site of donation of electrons by hydroxylamine. Treatment with Cd 2+ ions impairs the electron transport system on the reducing side of PS II. The decrease in the fluorescence yield of Chi a is less than that in the evolution of O2 mediated by oxidized phenylenediamine. This difference may be a result of inhibition on the reducing side of PS II. In addition to inhibition on the reducing side, Cd 2+ ions may affect the oxidizing side of PS II. A comparative study of the rates of evolution of O2 with /7-benzoquinone and dichloro-^7-benzoquinone as electron acceptors was performed since the halogenated benzoquinones have been shown to accept electrons from both active and inactive centers of photosystem II while some of the benzoquinones accept electrons only from active centers. The results suggest that Cd 2+ ions induced a marginal increase in the number of inactive reaction centers in PS II. Analysis of light-saturation-kinetics of the evolution of O2 catalysed by PS II indicates a reduction in the size of the antennae as well as in the concentration of the active (a-type) reaction centers of PS II. Thus, the Cd 2+ -induced effects on the photochemistry of PS II involve changes on the reducing side of PS II as well as possible changes in the sizes of the populations of active and inactive centers. Thus, short-term exposure to Cd 2+ ions during establishment of seedlings has a severely detrimental effect on photochemical activities in chloroplasts.
157 citations
TL;DR: It is concluded that salt stress itself does not exert adverse effects on the primary photosynthesis process since the F v /F m ratio and electron transport activity did not decrease with higher salt concentrations, however, salinity stress enhanced substantially the susceptibility to photoinhibition.
112 citations
TL;DR: Krogstad et al. as discussed by the authors showed that the Pb isotope composition of galena in these veins suggests that these fluids may have also introduced extraneous Pb from adjacent older granitoid gneisses into the amphibolites, which could account for the variability in the 207Pb/204Pb ratios of the samples.
Abstract: The late Archean, north-south trending Kolar Schist Belt in south India, 4 km wide by 80 km long, is thought to be a suture between two gneiss terranes (Krogstad et al. 1989). Within this volcanics-dominated belt are recognized both tholeiitic and high Mg (komatiitic and picritic) amphibolites, which make up some 70% and 5% respectively of the exposed outcrops. A massive tholeiitic amphibolite separates the belt into western and eastern parts. A Pb-Pb whole-rock age of 2732±155 Ma on samples from a single outcrop of massive tholeiite is a minimum age for this rock. Samples of this rock have ɛNd values at 2700 Ma that range between +3.8 and +6.8, μ1 (initial 238U/204Pb) of 7.5 and K1 (initial 232Th/238U) of about 4. Two different types of high-Mg amphibolites are recognized from the western part of the belt: a picritic or P-type, and a komatiitic or K-type. The P-type have highly variable Ce/Al ratios all greater than chondritic, Nd/Yb ratios greater than chondritic, ɛNd at 2700 Ma of +1.5 to +8, and Pb isotope compositions variable in 207Pb/204Pb with μ1 of about 8.0 and k1 of about 4. The trace-element data suggest that the light-REE enrichment is a character of the mantle source and is not due to residual garnet. The K-type amphibolites have near chondritic Ce/Al and Nd/Yb ratios, ɛNd at 2700 Ma of +1.5 to +8, and μ1 of about 8 and k1 of about 4. Although the P-type is light-REE enriched compared to the K-type, both types have similar Ce/Nd ratios as well as initial Pb and Nd isotopes. If the 2696±136 Ma age for the Sm-Nd isochron which includes both types of high-Mg amphibolite has any significance it dates the time of light-REE enrichment of the mantle source for the P-type komatiitic amphibolites. The high-Mg amphibolites in the eastern part of the belt are light-REE enriched, have Pb isotopic compositions that are variable in 207Pb/204Pb with a μ1 about 8.5 and ɛNd at 2700 Ma of +1.8 to +4.5. Hydrothermal fluids associated with metamorphism and shearing prior to about 2400 Ma ago were responsible for the introduction of gold-quartz-carbonate veins into the Kolar Schist Belt. The Pb isotope composition of galena in these veins suggests that these fluids may have also introduced extraneous Pb from adjacent older granitoid gneisses into the amphibolites, which could be responsible for the variability in the 207Pb/204Pb ratios of the samples. This extraneous Pb probably is not responsible for the distinct Pb isotope character of each type of amphibolite.
104 citations
TL;DR: The presence of proline in the incubation medium brought about a significant reduction in the time dependent loss in photochemical activity of thylakoids exposed to strong light suggesting that proline prevents photoinhibitory loss in chloroplast activity.
102 citations
TL;DR: The results on fluorescence indicate that salt stress predisposes photoin inhibition of plants and also reduces its ability to recover from photoinhibition.
95 citations
TL;DR: The fluorescence quantum yield of F758 is proportional to the concentration of P-700, which indicates that the cyanobacterium Spirulina platensis originates from chlorophyll (Ch1) a absorbing at 735 nm, and redox titration shows that F758 intensity has the same midpoint potential as P- 700.
77 citations
TL;DR: A temporal relationship between enzyme activity and mRNA levels was observed, thus suggesting that the expression of oxalate decarboxylase is regulated at the transcriptional level.
73 citations
Journal Article•
TL;DR: It has been shown that kidney HABP binds specifically to hyaluronic acid (HA) amongst all the glycosaminoglycans (GAGs), however, H ABP can interact with other matrix proteins, e.g., laminin, fibronectin, and collagen type IV.
66 citations
TL;DR: In the latter experiment, continued production of malondialdehyde during dark treatment suggests the degradation of unsaturated membrane lipids, and photosystem II (PSII), photosystem I (PSI), and whole chain reactions were impaired.
Abstract: Cucumber (Cucumis sativus L. cv Poinsette) plants were sprayed with 20 millimolar 5-aminolevulinic acid (ALA) and then incubated in dark for 14 hours. Upon transfer to sunlight (≃800 watts per square meter) the plants died after 5 hours of exposure due to photosensitization reaction of metalloporphyrins. Due to the photodynamic damage, photosystem II (PSII), photosystem I (PSI), and whole chain reactions were impaired. PSII activity was more susceptible to photodynamic damage than PSI. The variable fluorescence was significantly reduced in ALA-treated plants within 1 hour of exposure to sunlight. At low temperature (77°K), the PSI fluorescence peak height (F734) was drastically reduced and blue shifted by 6 nanometers. The photodynamic damage was irreversible; rather, it continued upon dark incubation of ALA-treated cucumber plants exposed to sunlight for 15 minutes. In the latter experiment, continued production of malondialdehyde during dark treatment suggests the degradation of unsaturated membrane lipids.
60 citations
TL;DR: This mini-review presents an assessment of the current knowledge on the role of lipids as modulators of ethanol tolerance and the adaptation by organisms in response to increasing concentrations of ethanol in their growth medium and changes in their plasma membrane lipid composition.
Abstract: This mini-review presents an assessment of the current knowledge on the role of lipids as modulators of ethanol tolerance. The adaptation by organisms in response to increasing concentrations of ethanol in their growth medium and changes in their plasma membrane lipid composition is also encompassed
TL;DR: In vivo labelling experiments showed that proteinase was not detectably accumulated in the cells, but was secreted immediately after synthesis, as well as BSA, other proteins (haemoglobin, ovalbumin, histone), peptone and tryptone, could induce proteinase, but to different levels.
Abstract: Candida albicans and some other pathogenic Candida species, when grown in a medium containing a protein as a sole source of nitrogen, secrete an acid proteinase. Culture supernatants were assayed for proteinase activity, and were also analysed by Western blotting with antibodies raised and affinity-purified against proteinase of C. albicans. Proteinases secreted by C. tropicalis and C. parapsilosis were antigenically related to that of C. albicans, but had different molecular masses. The proteinases secreted by C. lipolytica, C. rugosa and C. lusitaniae were not antigenically related. The kinetics of proteinase secretion by C. albicans were monitored by activity and by Western blotting. With BSA as the nitrogen source, proteinase secretion increased exponentially until about 16 h. Culture supernatants of BSA-grown cultures accumulated proteinase to about a 1000-fold higher level than those of ammonium-sulphate-grown cultures. In vivo labelling experiments showed that proteinase was not detectably accumulated in the cells, but was secreted immediately after synthesis. Immunoprecipitation of in vitro translated poly(A)-containing RNA identified a putative pre-protein of about 54 kDa. As well as BSA, other proteins (haemoglobin, ovalbumin, histone), peptone and tryptone, when used as nitrogen sources, could induce proteinase, but to different levels. When Casamino acids or an amino acid mixture (equivalent to the composition of BSA) was used as nitrogen source, no induction was observed. Ammonium sulphate, or any other ammonium salt, repressed secretion of proteinase.
TL;DR: The early Proterozoic Aravalli supergroup of Rajasthan near Nathdwara includes a thick basal unit of mafic volcanics with intercalated quartzites, referred to as picritic because of the absence of textural criteria as mentioned in this paper.
TL;DR: A secretory nature of hyaluronectin is established as it can be detected in the serum-free medium of AK-5 cells as it is localized on the cell surface and secreted into the medium.
TL;DR: Suspended and bed sediments collected from the entire region of the Godavari River basin were analyzed for Fe, Mn, Cr, Cu, Ni, and Zn.
Abstract: Suspended and bed sediments collected from the entire region of the Godavari River basin were analyzed for Fe, Mn, Cr, Cu, Ni, and Zn. There are pronounced temporal and spatial variations in the heavy metal distributions. The concentrations of heavy metals in the suspended sediments are significantly higher than the bed sediments.
TL;DR: It was evident that the administration of 250 and 500 mg coffee/kg body weight could significantly inhibit the in vivo genotoxicity of these carcinogens.
TL;DR: The origins of this pathological behavior are explored using methods of number theory and ergodic analysis, and the smallest nonlinearity asymptotically restores generic behavior.
Abstract: From the viewpoint of eigenvalue level statistics, harmonic-oscillator systems are unusual. Although integrable, these systems are nongeneric, and a spacing distribution does not exist even as the number of levels N\ensuremath{\rightarrow}\ensuremath{\infty}. The origins of this pathological behavior are explored using methods of number theory and ergodic analysis. However, such nongenericity is extremely fragile, and the smallest nonlinearity asymptotically restores generic behavior. These results are of relevance to the study of molecular spectra, as well as to the quasienergy spectra of integrable quantum maps.
TL;DR: In this paper, the authors argue that to prevent the outbreak of famine in the rural sector of underdeveloped countries, it is necessary, first, to identify the classes and groups which are vulnerable to starvation in the event of an economic shock.
Abstract: This article argues that in order to prevent the outbreak of famine in the rural sector of underdeveloped countries, it is necessary, first, to identify the classes and groups which are vulnerable to starvation in the event of an economic shock. The identification of the build‐up to a ‘pre‐famine conjuncture’ requires careful monitoring (a) of the long‐run trends in per head food availability (which can fall owing to the commercialisation of production even when overall growth in agriculture outstrips population growth), particularly on a regional basis, and (b) of the terms of trade for agriculture both vis‐a‐vis the domestic non‐agricultural sector as well as the rest of the world, when trade is important. These propositions are illustrated with reference to the Bengal famine of 1943–44, and to the trends in per head food production in India from 1960 to 1987.
TL;DR: A comparative analysis of earthworm populations in seral Khasi pine forest represented by Pinus kesiya 5-and 35-year old stands, and a climax broad-leaved mixed forests represented by a sacred grove was done at altitudes of 1500 m in Meghalaya in north-east India as mentioned in this paper.
Abstract: A comparative analysis of earthworm populations in seral Khasi pine forest represented by Pinus kesiya 5- and 35-year old stands, and a climax broad-leaved mixed forest represented by a sacred grove was done at altitudes of 1500 m in Meghalaya in north-east India. Tonoscolax horaii occurred under all forest types whereas Amynthas diffringens and Eulyphoeus feslivus were confined to pine forest stands only. Perionyx sp. and Drawida assamensis were restricted to the sacred grove. T. horaii had larger numbers in all three different forest types. This species offers possibilities of vermicullurc for biologically improving soil fertility in manmade ecosystems because of its wide range of tolerance.Generally earthworm populations were more active during the monsoon season; A. diffringens was however, more active during the winter, thereby conferring an advantage on this species as it was enabled to avoid competition during the monsoon season when other species dominate. Earthworm activity was generally higher in the sacred grove than in the pine forest stands. Population size was significantly correlated with soil moisture, temperature and pH. Wormcasts had a higher pH and nutrient status than the soil.In the highly leached soils of the humid tropics where there is a large concentration of fine root biomass in the surface soil layers, earthworm activity is beneficial because it helps incorporate detritus into the mineral soil rapidly and locally concentrates nutrients in the surface layers.
TL;DR: The glyoxalase I was purified from Brassica juncea by affinity chromatography on S‐hexyl GSH sepharose 4B and magnesium was found to stimulate the enzyme activity.
TL;DR: If mace was administered orally at the dose level of 10 mg/mouse per day for 7 days before and 90 days following carcinogen thread insertion, the cervical carcinoma incidence was 21.4%.
TL;DR: Genomic Southern blot analysis shows that the proteinase gene is present at a unique locus and that there is no other closely related gene in the C. albicans genome, suggesting that this gene can be used as a species-specific probe.
Abstract: Candida albicans secretes an acid proteinase when grown with a protein as a sole nitrogen source. The gene encoding this proteinase was isolated from a genomic expression library of C. albicans constructed in lambda gt11 by screening with antiproteinase antibodies. The affinity-purified antibodies used to verify the clones are monspecific; these do not cross-react with any other protein in the culture supernatants or crude extracts of C. albicans but strongly react with fusion proteins encoded by recombinant clones, revealing that these are true proteinase clones. Genomic Southern blot analysis shows that the proteinase gene is present at a unique locus and that there is no other closely related gene in the C. albicans genome. The proteinase gene probe identified two transcripts on Northern blots (RNA blots), which are present at a much higher level in C. albicans cells induced for proteinase secretion than in uninduced cells. The aspartyl proteinase gene reported earlier (T.J. Lott, L.S. Page, P. Boiron, J. Benson, and E. Reiss, Nucleic Acids Res. 17:1779, 1989) is not that of secretory acid proteinase, since the N-terminal amino acid sequence of secretory acid proteinase does not correspond to the deduced amino acid sequence of the aspartyl proteinase gene. The secretory acid proteinase gene was used to probe Southern blots of genomic DNA of several medically important Candida species and Saccharomyces cerevisiae. Under hybridization and wash conditions of low stringency, Candida tropicalis and Candida parapsilosis, in addition to C. albicans strains, gave specific signals, implying that C. tropicalis and C. parapsilosis have homologous secretory acid proteinase genes. However, under under wash conditions of high stringency, signals were obtained only with C. albicans strains, suggesting that this gene can be used as a species-specific probe. A simple yeast colony hybridization technique is sufficient to distinguish C. albicans from other yeasts.
TL;DR: When animals receiving similar treatments were put on a diet containing 1% mace during the periinitiational phase of tumorigenesis, the skin papilloma incidence was reduced to 50% and the average tumor per tumor-bearing mouse was only 1.75.
TL;DR: Effect of light quality showed that green light enhanced the synthesis of this chromophore as analyzed from the room temperature absorption spectra of phycocyanin subparticles and subunits, while red or white light did not have any effect.
Abstract: Phycobilisomes from the nonchromatic adapting cyanobacterium Spirulina platensis are composed of a central core containing allophycocyanin and rods with phycocyanin and linker polypeptides in a regular array. Room temperature absorption spectra of phycobilisomes from this organism indicated the presence of phycocyanin and allophycocyanin. However, low temperature absorption spectra showed the association of a phycobiliviolin type of chromophore within phycobilisomes. This chromophore had an absorption maximum at 590 nanometers when phycobilisomes were suspended in 0.75 molar K-phosphate buffer (pH 7.0). Purified phycocyanin from this cyanobacterium was found to consist of three subparticles and the phycobiliviolin type of chromophore was associated with the lowest density subparticle. Circular dichroism spectra of phycocyanin subparticles also indicated the association of this chromophore with the lowest density subparticle. Absorption spectral analysis of α and β subunits of phycocyanin showed that phycobiliviolin type of chromophore was attached to the α subunit, but not the β subunit. Effect of light quality showed that green light enhanced the synthesis of this chromophore as analyzed from the room temperature absorption spectra of phycocyanin subparticles and subunits, while red or white light did not have any effect. Low temperature absorption spectra of phycobilisomes isolated from green, red, and white light conditions also indicated the enhancement of phycobiliviolin type of chromophore under green light.
TL;DR: The results showed that the enzyme activity increased significantly in the deprived rat brain and it returned to control/normal level on recovery and would possibly help in explaining earlier observations.
Abstract: Acetylcholinesterase activity was compared in control, rapid eye movement sleep-deprived and recovered rat brain. The activity was estimated in the whole brain, cerebrum, brain stem and cerebellum. Flower pot technique was used for continuing deprivation for two, four and eight days. The results showed that the enzyme activity increased signficantly in the deprived rat brain and it returned to control/normal level on recovery. The enzyme activity increased first in the brain stem, while the activity in the cerebellum showed no significant change. Control experiments suggest that the increase was primarily caused by the deprivation. The finding fits well with existing knowledge and would possibly help in explaining earlier observations.
TL;DR: Some members of the family Amaranthaceae, which has mostly been reported as non-mycorrhizal, were examined for a symbiotic association with mycorrhiza in the semiarid and arid zones, and no correlation could be established between spore counts and either soil pH or soil moisture.
Abstract: Some members of the family Amaranthaceae, which has mostly been reported as non-mycorrhizal, were examined for a symbiotic association with mycorrhizae in the semiarid and arid zones. Ten species belonging to five genera, Achyranthes, Aerva, Alternanthera, Amaranthus, and Celosia were examined, using 1.0-cm long root standards. Intercellular hyphae, vesicles and arbuscules were observed in the root cortex. The number of different types of spores in the rhizosphere soil of different plants ranged from one to three. The spores isolated represented nine species belonging to four genera, Glomus, Gigaspora, Sclerocystis, and Scutellospora. No correlation could be established between spore counts and either soil pH or soil moisture.
TL;DR: Keoladeo Ghana National Park (at Bharatpur near Agra), well known for its avifauna, and Lake Kolleru wetland (east coast of India) exemplify the two management objectives respectively as discussed by the authors.
TL;DR: In vitro translation of total RNA revealed an increase in the synthesis of actin (45 kDa) during germ tube formation, suggesting for the first time that the expression of actIn gene is regulated during morphogenesis of C. albicans.
TL;DR: It is concluded that the dose-dependent suppressive effects of arecoline on DTH response to SRBC and on certain in vitro lymphocyte functions are more clear than the host resistance to endotoxin shock.
Abstract: Arecoline, a major alkaloid of arecanut was screened to explore its modulatory influence on cell-mediated immune response in a murine model system. the in viva and in vitro effects were evaluated at subtoxic concentrations of arecoline. Delayed type hypersensitivity (DTH) reactions to sheep red blood cells (SRBC) were evaluated in male mice. When treated subcutaneously with 20 mg/kg bw (1/5 of LD50) dose of arecoline for 1, 2 or 3 weeks, the DTH reactions were significantly suppressed. At arecoline concentration of 10 mg/kg bw, there was a moderate reduction in DTH response, while no appreciable change was observed at a dosage of 5 mg/kg bw. the effects were not dependent on the duration of treatment. In contrast, treating with arecoline continuously for 4 days following SRBC immunization showed significant suppression in DTH reactions at both 10 and 20 mg/kg bw doses. When treated after 12 h following immunization with 20 mg/kg bw arecoline, significant reduction in DTH reactions were seen. While...