Browsing by Author "S.K. Singh"

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3β,24-Dihydroxyolean-12-en-28-oic acid, a pentacyclic triterpene acid from Lantana indica
(1990) S.K. Singh; V.J. Tripathi; R.H. Singh
A new oleanane derivative, 3β,24-dihydroxy olean-12-en-28-oic acid, in addition to oleanolic and ursolic acids, has been isolated from the roots ofLantana indica. The structure of the new triterpene acid has been established by chemical and spectroscopic methods. © 1990 Pergamon Press plc.
A child with growth failure
(2003) S.K. Singh; A.G. Unnikrishnan; N.K. Agrawal; D. Kapoor; A.K. Sahoo; D.V.S. Reddy; R. Kumar
[No abstract available]
A comparative study of the epidermis of the common carp and the three Indian major carp
(1990) S.K. Singh; A.K. Mittal
A comparative study has been made of the mucogenic epidermis of the common carp, Cyprinus carpio var. communis, and the three Indian major carps, Catla catla, Labeo rohita and Cirrhina mrigala: on the basis of epidermis structural organization, these species are easily differentiated. The epithelial cells in the superficial layer, as in most fishes, show secretory activity, evidenced by positive histochemical reactions, which is high in C. carpio var. communis, moderate in C. catla and low in L. rohita and C. mrigala. The epithelial cells in the underlying two or three layers also give positive reactions, though their intensity is relatively weak. The mucous cells in C. carpio var. communis are distributed in large numbers arranged in several superimposed layers in the outer regions of the epidermis, whereas in C. catla they are fewer in number and are widely separated in the surface layers as well as in the deeper layers of the epidermis; in both species the mucous cells appear rounded, large, and open on the surface by wide pores. In contrast, in L. rohita and C. mrigala the mucous cells are smaller, restricted mainly to the superficial layer, close together in a single row, and open on the surface by narrow pores. The overall density of mucous cells in L. rohita and C. mrigala, as in C. catla, is much lower than in C. carpio var. communis. In the epidermis of C. carpio var. communis there are a large number of mucous cells, and the few club cells are restricted to the deeper layers. In contrast, in the epidermis of the three Indian major carp the overall density of the mucous cells is much lower and the club cells are very numerous. It is suggested that the high density of club cells compensates an overall low density of mucous cells as an adaptation for an effective defence mechanism. Increased mucus production in the epidermis of C. carpio var. communis, as evidenced by a large number of mucous cells in outer regions and high secretory activity of superficial layer epithelial cells, is associated with increased precipitation of mud held in suspension, needed as an adaptation to the species’peculiar bottom‐scooping habits. The varied density of the taste buds in the epidermis of the four carp is associated with their feeding habits. Copyright © 1990, Wiley Blackwell. All rights reserved
A computer program to study the effect of transition layer parameters on the Schlumberger apparent resistivity
(1997) M. Banerjee; S.K. Singh; Nagendra P. Singh; T. Lal
A computer program has been developed for the preparation of master curves of Schlumberger apparent resistivity function (qas/q1) versus the various values of half current electrode spacings over a horizontally stratified three-layered earth model having the intermediate interstratum as the transition layer. The interstratum has two types of conductivity variation: one, the linear variation, and second, the exponential variation of conductivity. The substratum has been taken as either highly resistive or conductive. The conductivity of the top layer merges with that of the substratum having a gradual variation of conductivity with depth in transition layer.
A new class of distribution having decreasing, increasing, and bathtub-shaped failure rate
(Taylor and Francis Inc., 2017) S.K. Maurya; A. Kaushik; S.K. Singh; U. Singh
In this article, we propose a new class of distribution which is based on the concept of exponentiated generalization with some modification so as to provide a better result in terms of flexibility. Our proposed distribution accommodates various shapes of hazard rate including the bathtub. Exponential distribution has been taken as the baseline distribution. Various statistical properties of the proposed distribution have been studied. We have used the method of maximum likelihood for estimation of the parameters of the proposed model. Last, we have analyzed four real datasets to illustrate the flexibility of the model in comparison to eight existing well-known distributions. © 2017 Taylor & Francis Group, LLC.
A new pentacyclic triterpene acid from lantana indica
(1991) S.K. Singh; V.J. Tripathi; R.H. Singh
A new pentacyclic triterpene acid 1 has been isolated from the roots of Lan-tana indica, and its structure has been established as 24-formyl-3-oxoolean- 12-en-28-oic acid by chemical and spectroscopic methods. © 1991, American Chemical Society. All rights reserved.
A Novel model for fast and robust retrieval of3d bio-images using intelligent vision algorithm
(Serials Publications, 2016) Meenakshi Srivastava; S.K. Singh; S.Q. Abbas; Neelabh
Vast growth of multimedia information like images, audio and video on web has induced the scientific community for storage and retrieval of multimedia information more intuitively. Since one image can be interpreted in numerous ways, keyword based searching systems can retrieve the information to a limited extent. Moreover in few domains for example, as in the case of Bio Images, the content information is not even of textual nature. This limitation has led to the requirement for development of Content Based Image Retrieval Systems. Image Retrieval systems which can recognize the objects like the human eyes have been most popular. To construct a good intelligent vision system, high dimension feature vectors of images are required for pattern recognition. Though high dimension feature vectors provides good recall rate, they retard the search process speed. Search time duration increases further with increase in number of images in database. In the present manuscript authors have proposed a model which adequately addresses these constraints and provides a robust and fast retrieval mechanism of Bio Images. © International Science Press.
A rare antibacterial flavone glucoside from Lantana camara
(Indian Drug Manufacturers' Association, 1997) D.K. Verma; S.K. Singh; Vyasji Tripathi
A rare flavone glucoside is isolated from the polar fraction of the leaves of Lantana camara. It was characterised as Pectolinarigenin -7-O-β.D. glucoside 1 by chemical and spectroscopic methods. The antibacterial activity is done against a wide range of Gram-positive and Gram-negative bacteria to determine the minimum inhibitory concentration.
Acrocephalosyndactyly - Type I (Apert's Syndrome)
(1999) S.K. Singh; Richa Chaturvedi; S.K. Pal; K.K. Singh; S.K. Sinha; J.K. Agrawal
[No abstract available]
Admissibility of a test procedure based on preliminary test of significance for life data
(1989) S.K. Singh; S.K. Upadhyay; Umesh Singh
Necessary and sufficient condition for admissibility of a test procedure based on preliminary test of significance for life data has been obtained. © 1989.
Adrenal function in patients with active pulmonary tuberculosis
(1998) S.K. Singh; J.K. Samaria; J.K. Agrawal
Thirty-three patients with active pulmonary tuberculosis of duration less than three years were evaluated for adrenal function by standard synacthen test. A comparison was made between patient group and control group. The basal plasma cortisol value was significantly higher in patient group than control group. All patients had normal post synacthen cortisol value indicating intact adrenal function. However, the functional reserve of adrenal gland assessed by the urea under the response curve showed lower functional reserve in the patient group in comparison with control group. Adrenal function was normal in patients with tuberculosis but hyponatermia was present in 24.24% of cases. This reflects that serum sodium is a poor marker and predictor of adrenal function in tuberculosis patients. In conclusion adrenal function is intact in patients with active pulmonary tuberculosis of duration less than 3 years inspite of high prevalence of hyponatremia and low functional reserve of adrenal gland.
Adrenocortical insufficiency in smear positive pulmonary tuberculosis.
(1992) S.C. Matah; G.L. Kesharwani; G.N. Srivastava; S.K. Singh; J.K. Agrawal
We studied 40 patients with pulmonary tuberculosis. All were positive for acid-fast bacilli (AFB) in the sputum. Their mean age was 30 yrs (range 10-50 yrs) and the duration of illness was 26.3 +/- 2.3 months. Radiologically minimal, moderately advanced and far advanced lesions were present in 7 (17.5%), 9 (22.5%) and 23 (57.5%) patients respectively. One patient with endobronchial lesion had no radiological evidence of pulmonary tuberculosis. Clinically, 14 patients (35%) had one or the other features of adrenocortical insufficiency. Postural hypotension was the commonest feature and was present in 11 patients (27.5%), followed by nausea and vomiting (20%), loss of axillary hair and libido (10%), skin and mucosal pigmentation in 7.5% of the cases. ACTH stimulation revealed incomplete adrenocortical insufficiency (partially responsive adrenal) in 5 patients (12.5%) and complete adrenocortical insufficiency (non-responsive adrenal) in 2 patients (5%). Patients with features of adrenal insufficiency had significantly longer duration of illness (p < 0.001) but there was no correlation with extent or type of lesion.
Adrenoleukodystrophy Presenting as Addison's Disease in Childhood
(2000) S.K. Singh; Richa Chaturvedi; J.K. Agrawal
[No abstract available]
Adsorption-desorption studies of cadmium in three different soil orders
(Technoscience Publications, 2014) Asha Sahu; S.K. Singh; Nisha Sahu; Bali Ram; M.C. Manna
Sorption isotherms have been widely used to assess the heavy metals retention characteristics of soil particles. Adsorption behaviour of cadmium (Cd) in soils is an important process which exerts a major influence on its uptake by plant roots. Desorption behaviour of the retained metals, however, usually differ from that of adsorption, leading to a lack of coincidence in the experimentally obtained adsorption and desorption isotherms. Three soils differing in physico-chemical properties (pH 5.7 to 8.2) and varied taxonomy (Typic Ustochrepts, Typic Rhodustalfs and Entic Chromusterts), were subjected to Cd treatment at various concentrations (0, 2, 4, 8, 15, 30, 45, 75 mg Cd/L). The Cd adsorbed by each soil was calculated as the difference between the amount of Cd present in the solution initially and that remaining after equilibration. Immediately after adsorption, desorption took place using successive dilution method with five consecutive desorption steps. Both, Cd adsorption and desorption data were described by Freundlich equation. The adsorption and desorption reactions, however, did not provide the same isotherms, indicating that hysteresis occurred in Cd adsorption-desorption process. Results indicated that the adsorption capacity of the soils for Cd increased with an increase in the pH or alkalinity of the soils. The rate of adsorption was, however, found to decrease with increased pH. But no specific trend was observed in case of desorption. All the three soils used in this study followed Freundlich adsorption isotherms. The adsorption data, in general, indicated that Cd was in a fixed form at higher pH levels. The Cd adsorption was in the order of Entic Chromusterts > Typic Ustochrepts > Typic Rhodustalfs.
Age and weight related bone mineral density in North Indian subjects
(2002) S.K. Singh; R. Kumar; N.K. Agrawal; A.G. Unnikrishnan; D.V.S. Reddy; S. Thazarth
The aim of this study is to assess the bone mineral density in different age and sex groups and to study the relationship between T-score and other parameters like age, sex and body weight. A population based cross sectional study of 398 subjects was conducted in the Department of Endocrinology and Metabolism, S.S. Hospital, BHU, Varanasi. Calcaneal bone mineral density was measured using an ultrasound bone densitometer (Pegasus). The subjects were subclassified for statistical analysis into age groups 15-30 years, 31-45 years, 46-60 years and above 60 years. Below the age of 45 years, mean T-score among females was significantly lower than males (-2.5 Vs - 1.79; p<0.01). Among females, a positive correlation between the weight and T-score was noted across all the age groups, with strongest correlation in 31-45 years age group (r=0.43). The strength of positive correlation declined after 45 years of age (r=0.18 below 45 years age, and r=0.11 above 60 years). Among males, there was a positive correlation between weight and T-score below 60 years, whereas the weight was negatively correlated with T-score (r=-0.17) beyond 60 years. The results of this cross sectional study suggest the bone mineral density varies with age, sex and body weight among North Indian subjects. Males had higher bone mineral density than females in all age groups particularly under the age of 45 years which might reflect the higher bone mass attained by males in their adulthood. The negative influence of age on bone mineral density was evident in females over 45 years and in males above 60 years of age. The positive correlation between weight and T-score was significant only in certain age groups in our study.
Air pollution tolerance index of plants
(1991) S.K. Singh; D.N. Rao; M. Agrawal; J. Pandey; D. Naryan
In order to evaluate the susceptibility level of plants to air pollutants, four parameters, namely ascorbic acid, chlorophyll, relative water content, and leaf-extract pH, were determined and computed together in a formulation signifying the air pollution tolerance index (APTI) of plants. APTI values of 69 plant species, including herbs shrubs and trees, growing in the urban-industrial Lahartara region of Varanasi were estimated. Plants with a high index value were tolerant to air pollutants and vice-versa. On the basis of their indices, different plant groups were categorized into sensitive, intermediate, moderately tolerant plant groups were categorized into sensitive, intermediate, moderately gigantea, C. roseus, etc. were tolerant and D. sissoo, L. chinensis, C. carandus, C. rottleri, etc. were sensitive to air pollutant. The susceptibility level of plants to air pollution, as indicated through their index values, compared well with the responses of plants observed under laboratory and field experiments. The APTI determination provides a reliable method for screening sensitive/tolerant plants under field conditions where the air-shed is contamined by a variety of pollutants. © 1991 Academic Press Limited.
AMIPRO: A content-based search engine for fast and efficient retrieval of 3D protein structures
(Springer Science and Business Media Deutschland GmbH, 2018) Meenakshi Srivastava; S.K. Singh; S.Q. Abbas; Neelabh
Proteins are macromolecules which are virtually involved in all of the life processes. The study of protein structures is of utmost importance in the field of bioinformatics. With the advancement in the field of computational biology, there has been tremendous upsurge in the sequential and the structural data deposition. The structure of a protein depends upon the sequence of the amino acids present in it, although similarity in sequence does not guarantee a similarity in structure. Despite the fact that the three-dimensional structure of protein molecule is very important to predict its functionality, yet the backbone of the searching has been majorly dependent upon the sequences rather than the structures. The leading platforms for searching structural similarity in proteins make use of sequence-based searching or text-based searching but do not provide the desired results. In the current manuscript, a model has been proposed to perform “content-based searching” on protein images. Content-based searching takes into account the visual/structure-based similarity and the information contained in the data sets rather than the traditional sequence-based searching. Intelligent Vision Algorithm has been applied to extract the visual features from the protein images for determining the similarity between two proteins. The proposed search engine model will result in an efficient and fast retrieval of similar protein structures. © 2018, Springer Nature Singapore Pte Ltd.
An antimicrobial principle from sphaeranthus indicus L. (family compositae)
(Informa Healthcare, 1988) S.K. Singh; K.M. Saroj; V.J. Tripathi; A.K. Singh; R.H. Singh
A bicyclic sesquiterpene lactone has been isolated from the petroleum ether extract of the aerial part of the Indian Composite Sphaeranthus indicus. The compound deonstrated strong antimicrobial activity against Staphylococcus aureus, S. albus, Escherichia coli, Fusarium sp., Helminthosporium sp. and other microorganisms. © 1988 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.
An antimicrobial principle from Sphaeranthus indicus L. (family compositae)
(1988) S.K. Singh; Saroj Km.; V.H. Tripathi; A.K. Singh; R.H. Singh
[No abstract available]
An insight into the possible mechanisms of antispermatogenic action of Dalbergia sissoo in male mice
(Blackwell Publishing Ltd, 2018) H.P. Verma; S.K. Singh
This study investigated the possible mechanisms of antispermatogenic action of Dalbergia sissoo in Parkes male mice. Mice were orally administered aqueous leaf extract of Dalbergia sissoo (50 and 100 mg kg−1 body weight day−1 for 35 days) and various testicular indices such 3β- and 17β-hydroxysteroid dehydrogenase (HSD) activities, Western blot analyses of StAR, cytochrome P450scc and caspase-3, germ cell apoptosis by TUNEL, and lipid peroxidation and antioxidant enzymes activities were assessed. A significant increase in lipid peroxidation level and a marked decrease in activities of superoxide dismutase, catalase, 3β- and 17β-HSD were noted in the testis of Dalbergia-treated mice compared to controls. The treatment also had adverse effect on expression levels of StAR and cytochrome P450scc in the testis. There was an increase in the number of TUNEL-positive germ cells and in expression level of caspase-3 in testes of Dalbergia-treated mice, especially in those treated with 100 mg dose compared to controls. By 56 days of withdrawal therapy, the alterations induced in the above parameters recovered to control levels. Our results thus suggest that Dalbergia treatment interferes with steroidogenesis and produces oxidative stress in the testis, which may induce germ cell apoptosis leading to suppression of spermatogenesis. © 2017 Blackwell Verlag GmbH