Browsing by Author "S.K. Roy"

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A CONTRIBUTION TO CYTOLOGY OF SOLANUM NIGRUM COMPLEX
(Indian Academy of Sciences, 1982) R.N. Singh; S.K. Roy
[No abstract available]
A cytotaxonomic survey of the pteridophyta of Australia
(2002) Mary D. Tindale; S.K. Roy
A cytotaxonomic survey of the ferns and fern allies of Australia (including Lord Howe Island) is presented. Five-hundred-and-twenty-six chromosome Counts of 268 Australian species, subspecies, varieties, variants and hybrids are recorded, only a small number having been previously investigated by other botanists on Australian material. Diploids represent c. 62% of the counts on species and c. 38% on polyploids, the latter ranging principally from triploids to a single decaploid and dodecaploid (but no heptaploids). More than one ploidy level has been reported in 19 taxa (almost 8% of taxa). Counts of 10x for Asplenium aethiopicum and 12x for A. flabellifolium are the highest definite ploidy levels for the Australian pteridophyte flora. Chromosome counts for 29 families and 89 genera are cited. Only diploids were reported for Osmundaceae and Cyatheaceae, but only polyploids for the Psilotaceae, Vittariaceae and Ophioglossaceae. An analysis is given of the levels of ploidy in 248 taxa, excluding the Lycopodiaceae and Hymenophyllaceae. The percentages of diploids and polyploids in Australian species are compared with those of nearby countries. Many species reported on here have never been cytologically investigated before, while others have not been studied previously on Australian material. The following genera have been examined cytologically for the first time: Coveniella Tindale, n = 41; Paraceterach (F. Muell.) Copel., n = 29; 'Oenotrichia Copel.', 2n = 82 (2x); Revwattsia (Watts) D.L.Jones, 2n = c. 328 (8x); and Pteridoblechnum Hennipman (2n = 54). The phylogeny of the genera is discussed in the light of these findings. Certain families such as the Adiantaceae, Cyatheaceae, Hymenophyllaceae, Lindsaeaceae and Marsileaceae were given special attention by collecting as much living material as possible. A number of species-complexes has been found and further chromosome counts added to intercontinental species complexes. The Döpp-Manton and Braithwaite forms of reproductive apomixis have been reported amongst some genera. Endemism, hybridity and apogamy amongst Australian pteridophytes are discussed, as well as homosporous and heterosporous species. The new combination Phymatosorus membranifolius (R.Br.) Tindale is made.
A MODIFIED TECHNIQUE FOR THE CLARIFICATION OF SOMATIC CHROMOSOMES
(Indian Academy of Sciences, 1981) S.K. Gupta; S.K. Roy
[No abstract available]
A new antheridiogen from the fern Pityrogramma calomelanos (L.) Link
(1985) J.P. Dubey; S.K. Roy
A new antheridiogen from Pityrogramma calomelanos of the family Polypodiaceae (Sensu Bower) has been extracted and tested on Pityrogramma calomelanos, Onychium siliculosum (Desv) C. chr, and Onychium japonicum (Thbg) Kze. The antheridiogen, here designated as Apit, did not produce uniform effect on the species tested. It promotes dark germination in all, but induces antheridia only in Pityrogramma calomelanos and Onychium siliculosum under light and dark conditions. The antheridium-inducing capacity of Apit is markedly different on the two ferns, being more vigorous under light condition in Pityrogramma calomelanos and less in Onychium siliculosum. Contrary to this, more antheridium-bearing prothalli have been counted in the latter under darkness. Higher dilutions are less effective in both. Dark germination has been found most effective in case of Onychium japonicum. The results indicate that the intensity of the effect of antheridiogen varies under different conditions and between species of the same genus. Also, an antheridiogen is not specific in the induction of antheridia or dark germination of spores, but it may initiate any of the two or both. © 1952 Indian Academy of Sciences.
A NOTE ON THE ANEUPLOIDY IN ARAIOSTEGIA PULCHRA (D. DON) COPEL. AND ASPLENIUM YOSHINAGAEMARINO VAR. PLANICAULE MORTON
(Indian Academy of Sciences, 1989) V.P. Singh; S.K. Roy
[No abstract available]
Biliary bile acids in cholelithiasis and carcinoma of the gall bladder
(1993) V.K. Shukla; S.C. Tiwari; S.K. Roy
The role of biliary deoxvcholate as an endogenous carcinogen and the possible association between cholelithiasis and the subsequent development of carcinoma of the gall bladder is unclear. This paper describes biliary bile acid analysis performed on three groups of patients, 10 with cholelithiasis, 10 with carcinoma of the gall bladder and 10 control patients. This is the first report of bile acid changes in carcinoma of the gall bladder. In these 30 patients the total bile acids concentration was highly variable (11.44-53.68 mg/ml). The mean ratio of primary to secondary bile acids was 3.5:1. This ratio was, however, significantly higher in cholelithiasis than in the control group (5.34:1; P 0.0011; patients with carcinoma of the gall bladder had significantly higher secondary bile acids (1:1; P 0.001). This is due to a marked increase in the secondary bile acids and indicates that raised biliary deoxycholate concentrations are present in patients with carcinoma of the gall bladder and therefore may well be a factor in carcinogenesis. © 1993 Rapid Communications of Oxford Ltd.
Carcinoma of the anal canal
(1980) B. Sanyal; G.C. Pant; K. Sahni; M.S. Agrawal; B.N. Bhatnagar; S.K. Roy; S. Gupta
104 cases of tumours of the anal canal were registered in the Department of Radiotherapy and Radiation Medicine, Institute of Medical Sciences, Banaras Hindu University, out of a total of 11,147 cases over a period of 10 years. The frequency was 0.98% of all cases. Squamous cell carcinoma was the most common tumour. All patients presented in a fairly advanced stage of the disease, 50% of which presented with inguinal lymph adenopathy at the first presentation. Only 55 patients out of 104 completed radiotherapy. 28 patients were managed on a curative line and 16 on a palliative basis. The majority of the patients had relief of symptoms following radiotherapy, but the overall survival at 3 and 5 years in this series was 41% and 33%, respectively. This presentation highlights the clinical spectrum of the cases, and the role of radiotherapy in the management of these tumours has been stressed.
Chemical constituents of a member of Adiantum caudatum complex
(1990) M. Gupta; A. Bagchi; S.K. Roy; A.B. Ray
[No abstract available]
Chromosome Association and Pollen Fertility in Solanum Melongena x S. Surattense hybrids
(1986) R.N. Singh; S.K. Roy
Intraspecific and interspecific relationship between Solanum melongena cv. Dorli, Round Black and S. surattense was investigated. Chromosome association and pollen sterility were also calculated for the parent and hybrids. The hybrid Dorli x surattense was possible only when the former was female parent. The fruits were obtained when the crosses were attempted between Round Black x Dorli but with sterile seeds. Some of these hybrids did not survive up to the flowering age. Round Black x surattense was unsuccessful in either direction. Cytological studies showed univalents frequently at diakinesis and metaphase I in the hybrid plants but not so in their parents. The univalents were due to the absence of pairing between homologous chromosomes. Laggards varying from 2 to 4 and bridges were observed in the hybrid plants. © 1986, Japan Mendel Society, International Society of Cytology. All rights reserved.
Comparative evaluation of the commonly performed emergency procedures for the prevention of recurrence of sigmoid volvulvus
(1977) B.N.S. Bhatnagar; S.K. Roy; M.R. Chakravarty
[No abstract available]
Comparison of Meiotic Abnormalities Induced by Gamma-rays between a Diploid and a Tetraploid Species of Physalis
(1985) S.K. Gupta; S.K. Roy
Radiosensitivity of a diploid (P. ixocarpa) and a tetraploid (P. peruviana) species of Physalis has been studied. Meiotic abnormalities induced by gammarays were compared in both species and found that it was always greater in tetraploid than in diploid species at each corresponding dose. The tetraploid plant due to greater chromosomal volume is more vulnerable to radiation hits and its immediate consequences are expected to contribute to the formation of sterile pollen, but this defect could be overcome by the buffering action of the unaltered genes over the altered ones at multiple loci, which normalizes the induced plant sterility. The diploid P. ixocarpa exhibited higher radiosensitivity than the tetraploid P. peruviana. Comparison between the frequencies of meiotic anomalies of M2 and M1 indicated that the latter has exaggerated values on these at all exposure levels. The lowered values of M2 indicated their elimination through diplontic selection or intrasomatic or competitive elimination during the course of time lapse. © 1985, Japan Mendel Society, International Society of Cytology. All rights reserved.
Comparison of MIC polluted soils of bhopal
(1988) D.S. Tripathi; S.K. Roy
MIC polluted two year stored soil sample from Bhopal were tried for supporting onion bulb growth. Observations revealed retardation of root growth due to induced cytological anomaly in their cells. The poor growth of roots and more chromosomal aberrations in the previous sample than in the latter show that the MIC worked as a retardant or inhibitor. The decrease of percent chromosomal aberrations and improvement of root growth in latter soil sample suggests lowering of the level of soil pollution caused by toxic methylisocyanate gas during leak at Bhopal. © 1988, Japan Mendel Society, International Society of Cytology. All rights reserved.
Correlation of immune and nutritional status with wound complicatons in patients undergoing abdominal surgery
(1985) V.K. Shukla; S.K. Roy; J. Kumar; M.P. Vaidya
The present study indicates the need for close scrutiny of the immune and nutritional status of patients undergoing abdominal surgery. Simple anthropometric measurements (weight and triceps skin fold thickness MAC) serologic testing (serum albumin), ALC, and skin testing are useful to identify patients with immunocompromise caused by nutritional deficiency. Early recognition and correction of immune nutritional deficits in patients undergoing abdominal surgery should lead to reduction in postoperative morbidity due to wound complication.
Cytogenetical studies on F1 hybrid of solanum lucani × S. Surattense var. Violet and white
(1989) G. Kumar; S.K. Roy
Interspecific hybrids between S. lucani and S. surattense (violet and white varieties both) were successful in forward and reciprocal directions. The crossability index between them was low, which suggests low degree of crossability relationships between hybridizing parents. Meiotic studies on parental genomes showed normal bivalents, most of which were ring shaped and chiasma frequency was high. Interspecific hybrids showed abnormal synapsis and unpaired chromosomes/chromosome parts with less staining ability. Metaphase I was characterized by the appearance of univalents, chains of three or six chromosomes, Y-shaped trivalent and rarely tetravalent association. Most PMCs contained 9 bivalents of which 5-7 were ring bivalents suggesting full homology between 7 chromosomes of S. surattense and 7 chromosomes of S. lucani, and the remaining 2 pairing partners exhibited partial homology by showing rod bivalents. Failure of synapsis in the rod bivalents could produce occasionally univalents only. Asymetrical chain made of three or six chromosomes indicated interchange of unequal segments due to heterozygosity for reciprocal translocation, in which 3 chromosomes from each parent were involved. Formation of Y-shaped trivalents was due to joint of interstitial break points. Further, occurrence of chromatid bridge with or without acentric fragments, presence of univalents, lagging and eliminated chromosomes indicated heterozygosity between parental genomes which contributed to formation of sterile pollen. However, all hybrids showed partial fertility except S. lucani × surattense var. white which was completely sterile. © 1989, Japan Mendel Society, International Society of Cytology. All rights reserved.
Cytology, Pollen Stainability and Yield in Desynaptic Autotetraploid Capsicum
(1984) R.N. Singh; S.K. Roy
Autotetraploidy was induced in the genus Capsicum annuum L., an economically important spice crop of considerable local importance. A few plants produced wrinkled fruits in the first generation with very few seeds in them and turned out to be desynaptic autotetraploid plants after cytological analysis. Pollen mother cells of the desynaptic autotetraploid showed either all or an overwhelming number of univalents. The bivalents included rod type and ring bivalents were very infrequent. The total absence of tri- and tetravalents was noteworthy. Failure of pairing between homologous chromosomes at prophase and metaphase I has been ascribed to desynaptic condition. Laggards were frequent and often formed small, supernumerary nuclei. © 1984, Japan Mendel Society, International Society of Cytology. All rights reserved.
Cytomorphological Studies of Dodecaploid (12x) Solanum nigrum Linn
(1985) R.N. Singh; S.K. Roy
Dodecaploid (12x) Solanum nigrum attained the highest level of ploidy in this genus with the help of colchicine. Cytomorphological studies have shown the colchiploid to have reduced height but larger, leathery leaves with broader stomata. The berries were bigger with larger and more numerous seeds in them. Pollen were bigger yet mostly fertile (85%). The induced dodecaploid (12x) plant showed diploid like meiosis which was unexpected at such a high level of autoploidy. © 1985, Japan Mendel Society, International Society of Cytology. All rights reserved.
Diagnostic role of hepatitis B-virus antigen and alpha fetoprotein in liver cancers
(1986) M. Kumar; S.K. Roy; T.M. Mohapatra; S. Khanna
[No abstract available]
Effect of gamma irradiation on dry seeds of solanum melongena l.: Observations on the m1generation
(1981) D.P. Srivastava; S.K. Roy
Effects of gamma radiation (dose range: 5-40 krad) on germination, survival, growth performance, injury, pollen sterility and yield were studied on the first generation plants (M1© Taylor & Francis Group, LLC.) of cultivars KT3and BG of Solarium melongena. Both varieties followed almost similar trends of radio response though the magnitude of effects produced by radiation at any dose level differed in the cultivars. Stimulation of germination was noted in KT3up to 15 krad and an increase in yield in BG up to 20 krad. In spite of approximately the samç LDjo values, while 40 krad caused 100% lethality in KT3the same resulted in 73% lethality in BG. © Taylor & Francis Group, LLC.
Effect of methylisocyanate gas polluted soil on Allium cepa L.
(1988) D.S. Tripathi; S.K. Roy
The root growth and cytology of Allium cepa L. have been studied using MIC gas polluted soil. The plants grown on polluted soil showed poor root growth and cytological abnormalities in root tip cells.
Efficacy of povidone-iodine (5%) in control of abdominal wound infection
(1984) A.K. Khanna; S.K. Roy; M.K. Misra
[No abstract available]