Browsing by Author "A. Mishra"

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2-Hydroxyestradiol-17β-induced oocyte maturation: Involvement of cAMP-protein kinase A and okadaic acid-sensitive protein phosphatases, and their interplay in oocyte maturation in the catfish Heteropneustes fossilis
(2006) A. Mishra; K.P. Joy
In Heteropneustes fossilis, in vitro incubation of postvitellogenic follicles with 2-hydroxyestradiol-17β (2-OHE2, 5 μmol l -1) decreased significantly the total cAMP level, concomitant with germinal vesicle breakdown (GVBD). The incubation of the follicles with cAMP or cAMP-elevating drugs [phosphodiesterase (PDE) inhibitors], such as IBMX (3-isobutyl-1-methyl-xanthine), theophylline and caffeine, inhibited the 2-OHE2-induced GVBD in a concentration-dependent manner. The magnitude of the response varied: both cAMP and IBMX were effective at all concentrations (0.1-2.0 mmol l-1), followed by theophylline (0.5-2.0 mmol l-1) and caffeine (1-2.0 mmol l-1). The protein kinase A (PKA) inhibitor H89 stimulated oocyte maturation in a concentration-dependent manner. However, when co-incubated with 2-OHE 2 for 24 h it produced a biphasic effect: low concentrations (0.1 and 1.0 μmol l-1) did not alter the 2-OHE2-induced GVBD, but high concentrations (5 and 10 μmol l-1) inhibited it. The incubation of the follicles with H89 lowered the inhibitory effect of IBMX on the 2-OHE2-induced GVBD. The incubation of the follicles with okadaic acid (OA), a protein phosphatase 1 and 2A inhibitor did not affect GVBD but when co-incubated with 2-OHE2, it enhanced the GVBD response. OA reversed the inhibitory effect of IBMX. The results suggest that OA may overcome the inhibition of 2-OHE2-induced GVBD by IBMX at a step distal to the cAMP-PKA pathway.
A review on preferential oxidation of carbon monoxide in hydrogen rich gases
(Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS), 2011) A. Mishra; R. Prasad
In this review, recent works on the preferential oxidation of carbon monoxide in hydrogen rich gases for fuel cell applications are summarized. H2 is used as a fuel for polymer-electrolyte membrane fuel cell (PEMFC). It is produced by reforming of natural gas or liquid fuels followed by water gas shift reaction. The produced gas consists of H2, CO, and CO2. In which CO content is around 1%, which is highly poisonous for the Pt anode of the PEMFC so that further removal of CO is needed. Catalytic preferential oxidation of CO (CO-PROX) is one of the most suitable methods of purification of H2 because of high CO conversion rate at low temperature range, which is preferable for PEMFC operating conditions. Catalysts used for CO-PROX are mainly noble metal based; gold based and base metal oxide catalysts among them Copper-Ceria based catalysts are the most appropriate due to its low cost, easy availability and result obtained by these catalysts are comparable with the conventional noble metal catalysts. © 2011 BCREC UN-DIP.
A triterpenoid from Moringa pterygosperma
(Chemical Publishing Co., 2002) A. Mishra; G.P. Dubey
A triterpene is isolated direct from the hexane extract of the bark cf Moringa pterygosperma. This is identified as leupol.
Assessment of water quality using principal component analysis: A case study of the river Ganges
(2010) A. Mishra
In present study multivariate statistical approaches are used; interpretation of large and complex data matrix obtained during a monitoring of the river Ganges in Varanasi. 16 physicochemical and bacteriological variables have been analyzed in water samples collected every three months for two years from six sampling sites where river affected by man made and seasonal influences. The dataset was treated using Principal Component Analysis (PCA) to extract the parameters that are most important in assessing variation in water quality. Four Principal Factor were identified as responsible for the data structure explaining 90% of the total variance of the dataset, in which nutrient factor (39.2%), sewage and feacal contamination (29.3%), physicochemical sources of variability (6.2%) and waste water pollution from industrial and organic load (5.8%) that represents total variance of water quality in the Ganges River. The present study suggests that PCA techniques are useful tools for identification of important surface water quality parameters. © 2010 Allerton Press, Inc.
Compact dualband rectangular microstrip patch antenna for 2.4/5.12-GHz wireless applications
(Kluwer Academic Publishers, 2015) A. Mishra; J.A. Ansari; Km. Kamakshi; A. Singh; Mohd. Aneesh; B.R. Vishvakarma
A dual-band antenna is proposed for WLAN and WiMAX frequency bands. Two resonance frequencies are found to be 2.45 and 5.125 GHz and −10 dB bandwidth of lower and upper resonance frequencies are 4.13 and 8.82 % respectively. It is observed that frequency ratio is more sensitive with the dimensions of L-shaped slot. The frequency ratio of the antenna for a given dimension of L-slot is found to be 2.092 and gain of the antenna is 3.9 dBi for lower resonance whereas 6 dBi at upper resonance. The theoretical results are compared with the reported experimental result as well as simulated results obtained from IE3D simulation software which are in close agreement. © 2014, Springer Science+Business Media New York.
Comparative evaluation of parasitology and serological tests in the diagnosis of visceral leishmaniasis in India: A phase III diagnostic accuracy study
(2007) S. Sundar; R.K. Singh; S.K. Bimal; K. Gidwani; A. Mishra; R. Maurya; S.K. Singh; K.D. Manandhar; M. Boelaert; M. Rai
In this phase III trial for diagnostics for visceral leishmaniasis (VL) in India, we compared parasitological diagnosis with several serological tests: direct agglutination test (freeze dried; DAT-FD), rK-39 strip test, rK-26 strip test and a latex agglutination test for antigen detection in urine (KAtex) in 452 subjects from the endemic regions of Bihar, India. The subjects were segregated into four categories: 230 confirmed patients, 52 probable cases, 70 non-cases and 100 healthy endemic controls. The first two groups were used for estimating sensitivity, the latter two for specificity. Sensitivity of DAT-FD was 98.9%, rK-39: 98.9%, KAtex: 67.0% and rK-26: 21.3%. Sensitivity of DAT-FD on blood taken on filter paper (DAT-FDF) was 99.3%, which was comparable with that using serum. Specificity of serological tests was comparable and high (DAT-FD and DAT-FDF: 94%, rK-39 strip test: 97%, KAtex: 99% and rK-26 strip test: 100%). The classical 'gold standard' parasitological demonstration in splenic smear performed poorly as it missed 18.4% of cases that benefited from VL treatment. Reproducibility of the serological tests between field and central laboratories was excellent (κ = 1.0, 0.99, 0.96 and 0.94 respectively for microscopy, DAT-FD, rK-39 strip test and rK-26 strip test). A high degree of agreement was observed between DAT-FD and rK-39 strip test (κ = 0.986). Although DAT-FD and rK-39 strip test were highly sensitive with excellent specificity, the ease of use of the latter makes it most suitable for the diagnosis of VL in the field conditions. © 2007 Blackwell Publishing Ltd.
Comparative study of various preparation methods of CuO-CeO2 catalysts for oxidation of n-hexane and iso-octane
(Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS), 2013) A. Mishra; B.D. Tripathi; A.K. Rai; R. Prasad
The complete oxidation of n-Hexane and iso-Octane was studied individually in a fixed bed tubular flow reactor over CuO-CeO2 catalysts synthesized via four different methods namely urea-nitrate combustion method, urea gelation/co-precipitation method, citric acid sol-gel method and co-impregnation method. Laser diffraction was employed in catalysts characterization. The results obtained from the complete conversion of n-Hexane and iso-Octane revealed that the CuO-CeO2 catalysts prepared by urea-nitrate combustion method (UNC) showed the best performance than the catalysts prepared by other methods used in the present investigation. CuO-CeO2 catalysts prepared by UNC method achieve total n-Hexane and iso-Octane conversion to CO2 at lower temperatures of 280 °C and 340 °C respectively due to the larger surface area of the catalysts which increases the specific rate of reaction. © 2013 BCREC UNDIP.
Contre-coup extradural haematoma: A short report
(2001) A. Mishra; S. Mohanty
An extradural haematoma contralateral to impact site is reported. Review of literature reveals that such phenomenon is extremely rare.
Development of repaglinide loaded solid lipid nanocarrier: Selection of fabrication method
(2010) M.K. Rawat; A. Jain; A. Mishra; M.S. Muthu; S. Singh
Repaglinide solid lipid nanoparticles (RG-SLN) were fabricated using stearic acid as lipid. Pluronic F68 (PLF68) and soya lecithin were used as a stabilizer. SLNs were prepared by modified solvent injection and ultrasonication methods. SLNs prepared with modified solvent injection method have larger particle size (360±2.5nm) than prepared with ultrasonication method (281±5.3nm). The zeta potential of the prepared formulations by these two methods varied from - 23.10 ±1.23 to -26.01 ±0.89 mV. The maximum entrapment efficiency (62.14 ±1.29%) was obtained in modified solvent injection method. The total drug content was nearly same (98%) in both the methods. In vitro release studies were performed in phosphate buffer (pH 6.8) with 0.5% sodium lauryl sulphate (SLS) using dialysis bag diffusion technique. The cumulative drug release was 30% and 50% within 2 hrs in modified solvent injection and ultrasonication method, respectively. This indicates that RG-SLN prepared from modified injection method released the drug more slowly than SLNs prepared with ultrasonication method. Differential scanning calorimetry indicates that repaglinide (RG) entrapped in the solid lipid nanoparticles (SLN) exist in an amorphous or molecular state. Repaglinide loaded solid lipid nanoparticles prepared with both methods were of spherical shape as observed by transmission electron microscopy (TEM). These results suggest that modified solvent injection method is more suitable for preparation of repaglinide SLNs using stearic acid. © 2010 Bentham Science Publishers Ltd.
Distribution and ethnic variation of â-thalassemia mutations in Nepal.
(2012) A. Mishra; A. Mukherjee; A. Roy; G. Singh; P. Shrestha; R.R. Singh; V. Rohil; N. Baral; S. Majhi; D. Dash
This is the first study characterizing spectrum of beta-thalassemia mutations in Nepalese population. Mutations were analyzed in 22 patients using 10 sets of allele-specific primers. Five of the mutations, namely F.S 41/42 (--TCTT), IVS1 nt5 (G-->C), IVS1 nt1 (G-->T), 619 bp deletion and F.S 8/9 (+G), were found to constitute 87.82% of total alleles studied. F.S 41/42 (--TCTT) was the commonest mutation. -88 (C-->T), Codon 16 (--C) and Codon 15 (G-->A), had a combined frequency of 12.18%. Distribution of mutations causing beta-thalassemia in different ethnic Nepalese groups was analyzed. The mutational profile in Nepal share several similarities with that from the two neighboring countries, India and China. Detection of more than one mutation in three cases of thalassemia trait raises the likelihood of existence of multiple mutations in cis in Nepalese thalassemic carriers. Such possibility has to be carefully considered while developing prenatal screening program for Nepalese population.
Effects of gonadotrophin in vivo and 2-hydroxyoestradiol-17β in vitro on follicular steroid hormone profile associated with oocyte maturation in the catfish Heteropneustes fossilis
(2006) A. Mishra; K.P. Joy
An HPLC method was used to tentatively identify progesterone (P4) and its metabolites (17-hydroxyprogesterone (17-P4) and 17,20β-dihydroxy-4-pregnen-3-one (17,20β-P)), corticosteroids (cortisol and corticosterone) and testosterone in ovary/follicular preparations of the catfish Heteropneustes fossilis associated with in vivo or in vitro oocyte maturation/ovulation. A single i.p. injection of human chorionic gonadotrophin (100 IU/fish, sampled at 0, 8 and 16 h) induced oocyte maturation and ovulation, which coincided with significant and progressive increases in 17,20β-P, and P4 and 17-P4 the precursors of the former. Both cortisol and corticosterone also increased significantly. Conversely, testosterone decreased significantly and progressively over time. Under in vitro conditions, incubation of post-vitellogenic (intact) follicles or follicular envelope (layer) with 2-hydroxyoestradiol (2-OHE2, 5 μM for 0, 6 and 24 h) elicited a sharp significant increase in 17,20β-P, the increase being higher in the follicular envelope incubate. P4 and 17-P4 also registered significant increases over the time with the peak values at 24 h. Cortisol and corticosterone increased significantly in the intact follicle, but not in the follicular envelope incubate. Testosterone decreased significantly in the intact follicle, but increased significantly (24 h) in the follicular envelope incubate. Coincident with these changes, the percentage of germinal vesicle breakdown (GVBD) increased over the time in the intact follicle incubate (48.9% at 6 h and 79.8% at 24 h). Denuded oocytes on incubation with 2-OHE2 (5 μM) did not produce any significant change in the percentage of GVBD or in the steroid profile. While corticosterone and 17,20β-P were undetected, P4, 17-P4, cortisol and testosterone were detected in low amounts. The results show that the 2-OHE2-induced GVBD response seems to be mediated through the production of 17,20β-P and corticosteroids. It is suggested that hydroxyoestrogens seem to be a component in the gonadotrophin cascade of regulation of oocyte maturation/ovulation in the catfish. © 2006 Society for Endocrinology.
Efficient tillage and nutrient management practices for sustainable yields, profitability and energy use efficiency for rice-based cropping system in different soils and agro-climatic conditions
(2013) G. R. Maruthi Sankar; K.L. Sharma; K. Srinivas Reddy; G. Pratibha; Reshma Shinde; S.R. Singh; A.K. Nema; R.P. Singh; B.S. Rath; A. Mishra; B.D. Behera; C.R. Subudhi; Bhagwan Singh; H.C. Singh; Ashok Kumar Singh; D.K. Rusia; M.S. Yadava; C.R. Thyagaraj; P.K. Mishra; M. Suma Chandrika; B. Venkateswarlu
Long-term tillage and fertilizer experiments were conducted in rice in kharif followed by lentil in dry subhumid Inceptisols at Varanasi and Faizabad; horse gram at Phulbani and linseed at Ranchi in moist subhumid Alfisols in rabi during 2001 to 2010. The study was conducted to assess the effect of conventional tillage (CT), low tillage + interculture (LT1) and low tillage + herbicide (LT2) together with 100% N (organic) (F1), 50% N (organic) + 50% N (inorganic) (F2) and 100% N (inorganic) (F3) on productivity, profitability, rainwater and energy use efficiencies. The results at Varanasi revealed that CT was superior with mean yield of 2389 kg ha-1, while F1 was superior with 2378 kg ha-1 in rice. At Faizabad, CT was superior with mean rice yield of 1851 kg ha-1 and lentil yield of 977 kg ha -1, while F1 was superior with 1704 and 993 kg ha-1 of rice and lentil, respectively. At Phulbani, F2 was superior with rice yield of 1170 kg ha-1. At Ranchi, F2 with rice yield of 986 kg ha-1 and F3 with linseed yield of 224 kg ha-1 were superior. The regression model of crop seasonal rainfall and yield deviations indicated an increasing trend in rice yield over mean (positive deviation) with increase in rainfall at all locations; while a decreasing trend (negative deviation) was found for lentil at Faizabad, horse gram at Phulbani and linseed at Ranchi. Based on economic analysis, CTF1 at Varanasi and Faizabad, CTF2 at Phulbani and LT2F2 at Ranchi were superior. Copyright © 2013 Cambridge University Press.
Enhanced biosorption of metal ions from wastewater by Fenton modified Hydrilla verticillata dried biomass
(Center for Environmental and Energy Research and Studies, 2015) A. Mishra; B.D. Tripathi; A.K. Rai
Present study deals with the biosorption of metal ions (Cu2+, Zn2+, Pb2+, and Cd2+) from aqueous solutions as well as from wastewater using Fenton modified Hydrilla verticillata dried biomass. Fenton modification process was optimized by varying different parameters such as pH, temperature, contact time, and Fe2+/H2O2 ratio. The modified biosorbent was characterized by using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and Malvern particle size analyzer. Energy-dispersive X-ray spectroscopy analysis revealed the enhancement in weight percent of Cu2+ (47.53 %), Zn2+ (41.82 %), Pb2+ (43.76 %), and Cd2+ (43.15 %) ions on the surface of modified biosorbent after the biosorption process. The experimental data obtained from the batch study were modeled using Langmuir and Freundlich isotherm models. Experimental data showed best fitting to Freundlich isotherm model. The increase in biosorption capacity after the Fenton modification was observed, which follows the sequence: Cu2+ > Pb2+ > Cd2+ > Zn2+. The biosorption process followed the pseudo-second-order kinetics, suggesting that the chemisorption may be the rate-limiting step in this study. The thermodynamic study revealed that the biosorption process was spontaneous and exothermic in nature. The biosorption capacity for multi-metal solution was found to be relatively lower than the single-metal solution. Performance of batch reactor in treating wastewater showed significant increase in removal efficiency of Cu2+ (from 74 to 96 %), Zn2+ (from 67 to 84 %), Pb2+ (from 71 to 92 %), and Cd2+ (from 71 to 89 %) ions after the modification of biosorbent as compared to raw biomass. © 2014, Islamic Azad University (IAU).
Experimental study on anti inflammatory activity of Shyonaka (Opoxylum indicum Vent.)
(1975) A. Mishra; P.V. Sharma
[No abstract available]
Fetal growth variations. I. Influence of maternal size and nutrition on identification of fetal growth retardation
(1983) V. Bhargava; M. Chatterjee; A. Prakash; B. Bhatia; A. Mishra
[No abstract available]
Functional organization of polytene X chromosome in two X chromosome inversion carrying larvae of Drosophila melanogaster reared at 24°C pr at 10°C
(1982) S.C. Lakhotia; A. Mishra
[No abstract available]
Genetics and visceral leishmaniasis: Of mice and man
(2009) J.M. Blackwell; M. Fakiola; M.E. Ibrahim; S.E. Jamieson; S.B. Jeronimo; E.N. Miller; A. Mishra; H.S. Mohamed; C.S. Peacock; M. Raju; S. Sundar; M.E. Wilson
Ninety per cent of the 500 000 annual new cases of visceral leishmaniasis (VL) occur in India/Bangladesh/Nepal, Sudan and Brazil. Importantly, 80-90% of human infections are sub-clinical or asymptomatic, usually associated with strong cell-mediated immunity. Understanding the environmental and genetic risk factors that determine why two people with the same exposure to infection differ in susceptibility could provide important leads for improved therapies. Recent research using candidate gene association analysis and genome-wide linkage studies (GWLS) in collections of families from Sudan, Brazil and India have identified a number of genes/regions related both to environmental risk factors (e.g. iron), as well as genes that determine type 1 vs. type 2 cellular immune responses. However, until now all of the allelic association studies carried out have been underpowered to find genes of small effect sizes (odds ratios or OR < 2), and GWLS using multicase pedigrees have only been powered to find single major genes, or at best oligogenic control. The accumulation of large DNA banks from India and Brazil now makes it possible to undertake genome-wide association studies (GWAS), which are ongoing as part of phase 2 of the Wellcome Trust Case Control Consortium. Data from this analysis should seed research into novel genes and mechanisms that influence susceptibility to VL. © 2009 Blackwell Publishing Ltd.
Heavy metal and microbial pollution of the River Ganga: A case study of water quality at Varanasi
(2010) P.K. Rai; A. Mishra; B.D. Tripathi
The work presented here analyzed water samples from three sewage treatment plants which regularly discharge into the River Ganga. Biological oxygen demand and dissolved oxygen values were well above the permissible limit at all sites, and were recorded as being at maximum at Dinapur sewage treatment plant. Heavy metals (Zn, Cu, Cd, Pb, Cr) in disposed effluents were above permissible limits at all three sites. Likewise, the most probable number index of E. coli in water samples and coliform counts were recorded as being higher in irrigated water samples and vegetables, indicating a serious health hazard posed by intense microbial and faecal pollution. It was recommended that an integrated approach of phytoremediation with aquatic macrophytes and ozonization of wastewater be adopted to curb the heavy metals and microbial pollution based on these recent research investigations. © 2010 AEHMS.
Higher-order cranking calculations in the interacting boson model
(1987) A. Mishra; A.N. Mantri
It is shown that IBM cranking calculations, carried out by including a time-odd parameter in the definition of intrinsic states of IBM in the lowest order of angular frequency, give reasonably good estimates for the ground-state moment of inertia, but when extended to higher order they produce an unphysical variation of the moment of inertia with frequency. An alternative expression for the ground-state moment of inertia within the IBM framework without using time-odd parameter is briefly discussed.
HPLC-electrochemical detection of ovarian estradiol-17β and catecholestrogens in the catfish Heteropneustes fossilis: Seasonal and periovulatory changes
(Academic Press Inc., 2006) A. Mishra; K.P. Joy
A high performance liquid chromatography-electrochemical (HPLC-EC) detection method was used to characterize estradiol-17β (E2) and its metabolites (2-hydroxyE2, 4-hydroxyE2, and 2-methoxyE2) and investigate their seasonal and periovulatory changes in the ovary of the catfish Heteropneustes fossilis. The retention times in minutes of standards determined by individual and mixture applications are: 2-OHE2-6.6, 4-OHE2-7.0, 4-OHE1-11.2, E 2-12.0, and 2-methoxyE2-15.2. Since the retention times of 2-OHE2 and 4-OHE2 merged at higher concentrations, the elution peaks of the sample were taken as due to both (2/4-OHE2) for analysis. The steroids were not detectable in the resting and postspawning phases and 2-methoxyE2 was not detectable in the recrudescent (preparatory, prespawning, and spawning) phases as well. E2 and 2/4-OHE2 have maintained an inverse relationship in the recrudescent phase. The E2 concentration was the highest in the preparatory phase (April) with active vitellogenic activity and declined significantly across prespawning and spawning phases (P < 0.001, one way ANOVA; P < 0.05, Newman-Keuls' test). On the other hand, the concentration of 2/4-OHE 2, which was the lowest in the preparatory phase, increased significantly to the peak level in the spawning phase. A single intraperitoneal injection of hCG (100 IU/fish) stimulated significantly the formation of 2/4-OHE2 at 8 h with a simultaneous reduction in E2. 2-MethoxyE2 was detected only after 16 h of the hCG injection. The functional significance of catecholestrogens in the seasonal reproductive cycle and during the hCG-induced ovulation of the catfish was discussed. © 2005 Elsevier Inc. All rights reserved.