P. C. Datta

Bio: P. C. Datta is an academic researcher from University of Calcutta. The author has contributed to research in topic(s): Bark & Pharmacognosy. The author has an hindex of 7, co-authored 28 publication(s) receiving 173 citation(s).

Application of Improved Technique in Tracing Karyotype Differences Between Strains of Lathyrus odoratus L

Abstract: In order to find out how far karyotypic changes or undetectable gene mutations have been associated with the origin of different varieties of Lathyrus odoratus, which differ in flower colour, leaf nature, tendril character etc., a thorough analysis of the karyotype of different pure varieties of L. odoratus have been carried out in the present investigation. For this purpose a new improved method involving pre-treatment with paradichlorobenzene was employed and the procedure for all the strains had been kept constant.It has been revealed, that in spite of a homogeneity amongst all the strains, each strain is characterised by its own karyotype. They mainly differ with respect to the number and position of constriction regions in chromosomes. All these facts suggest that the structural changes of chromosomes have always been associated with the evolution of different varieties.Regular meiosis noticed in these strains can be explained by assuming that through extensive cultivation and selection all the structural alterations have attained a state of homozygosity.

Medicinal Species of Piper, Pharmacognostic Delimitation

Abstract: The genus Piper (Piperaceae) is a large one. Jackson (1869) and Salisbury (1959-60) mention 600-700 species, Willis (1973) 2000. Hooker (1882) recorded only 24 species in India. “Wealth of India” mentions 30 species for India. About eight Indian species have therapeutic importance (Chopra et al., 1956). Four of these species, very common and widely used, have been selected for detailed study: Piper betle L. (Tambuli in Sanskrit, Pan in Bengali, Tamvettilai in Tamil), Piper cubeba L. f. (Sugandha muricha in Sanskrit, Kabachini in Bengali), Piper longum L. (Pippali in Sanskrit, Pipul in Bengali and Pippallu in Telegu) and Piper nigrum L. (Maricha in Sanskrit, Milagu in Tamil, Golmorich in Hindi and Bengali). A critical study of the pharmacognostic characters, though almost unexplored (Datta and Mukherji, 1952; Tyler and Schwarting, 1968), is worth attempting, particularly for detecting adulteration in commercial supplies.

Cytotaxonomy of Piperaceae

Abstract: From a comparison of the chromosome numbers of different species, it appears that 11 is the basic number of Peperomia and 12 of Piper. Variation in the reports of chromosome number of the same species may be due to occurrence of chromosomal biotypes.The trend of evolution in the two genera (Peperomia and Piper) appear different, numerical and structural change in the former, and polyploidy in the latter. The basic number (x=11) is represented by Peperomia argyreia, where structural alteration is clear. x×12 is represented by Pep. metallica, Pep. obtusifolia and Pep. pellucida, polyploidy occurring only in the last one.Piper cubeba (2n=24), P. magnificum (2n=24) and P. longum (2n=48), probably form a basic group of Piper. P. nigrum (2n=36, 60) is more advanced in chromosome structure. P. betle (2n=64) represents a different line having x=8 or 16.Records of chromosome number suggest that Peperomia is more primitive than Piper.

Chromosomal Biotypes of Carica papaya Linn

Abstract: Five horticultural forms of Carica papaya growing in India have been studied. Karyotypes of them represent homogeneity. Slight structural difference in chromosomes of different varieties is noticed, which proves the role of structural alteration of chromosomes on the evolution of the forms. No heteromorphic pair, or unpaired chromosome or any chromatin body, suggesting chromosomal basis of sex difference in the species, could be recognized.

Chromosome studies in species ofDracaena with special reference to their means of speciation

Abstract: Detailed study of the structure and behaviour of chromosomes in the somatic tissue of twenty-one species of the genusDracaena has been made and the “normal” chromosome numbers of all these species have been reported for the first time in this paper. The previous and the present records suggest that most of the species possess a number of chromosomal biotypes. These biotypes mainly differ with respect to their chromosome numbers. Relationship between species showing multiples of different series of chromosome numbers, viz. eight, ten, thirteen, seventeen and nineteen has been indicated. On the basis of the fact that a general resemblance in gross morphology of chromosomes and similarity in total amount of chromatin length are present amongst different species of the genusDracaena, it has been suggested that the species of this genus represent a homogeneous assemblage in spite of the fact that inconstancy in chromosome number is noted within a species. The different lines have mainly been assumed to have come out through continued production of aneuploid numbers during evolution. The presence of a number of chromosomal biotypes indicates that such aneuploid numbers often arise. Minor differences in details of chromosome morphology, and the presence of super-numerary constrictions in certain species, have been regarded as proving that structural changes of chromosomes have also played a distinct role in evolution of the species. As the different species ofDracaena are propagated exclusively through vegetative means, the only explanation for the origin of biotypes which can be suggested is that the recorded variant nuclei enter into the formation of new daughter shoots from which new individuals originate with different genomic constitutions. As flowers are scarcely noted and sexual reproduction is entirely ineffective with respect to propagation, this seems to be the only way through which speciation is effected here.

The Families And Genera Of Vascular Plants

Abstract: Perp. punya vol. X. Flowering plant, eudicots : sapindales, cucurbitales, myrtaceae. Perp.punya: 1eks.

Flavopiridol Induces Apoptosis of Normal Lymphoid Cells, Causes Immunosuppression, and Has Potent Antitumor Activity In Vivo Against Human Leukemia and Lymphoma Xenografts

Abstract: Flavopiridol is a novel semisynthetic flavone derivative of the alkaloid rohitukine. Flavopiridol is known to inhibit potently the activity of multiple cyclin-dependent kinases. We have assessed its effects on normal and malignant cells in preclinical animal models of localized and disseminated human hematopoietic neoplasms. Flavopiridol, when administered as daily bolus intravenous (IV) injections, produced selective apoptosis of cells in the thymus, spleen, and lymph nodes, resulting in atrophy of these organs. With the exception of the intestinal crypts, apoptosis or tissue damage was absent in all other organs investigated (kidneys, liver, lungs, bone/bone marrow, muscle, and heart). Flavopiridol had a marked apoptotic effect documented by DNA nick-end labeling, or DNA agarose gels in xenografts of human hematopoietic tumors HL-60, SUDHL-4, and Nalm/6. After treatment with 7.5 mg/kg flavopiridol bolus IV or intraperitoneal on each of 5 consecutive days, 11 out of 12 advanced stage subcutaneous (s.c.) human HL-60 xenografts underwent complete regressions, and animals remained disease-free several months after one course of flavopiridol treatment. SUDHL-4 s.c. lymphomas treated with flavopiridol at 7.5 mg/kg bolus IV for 5 days underwent either major (two out of eight mice) or complete (four out of eight mice) regression, with two animals remaining disease-free for more than 60 days. The overall growth delay was 73.2%. The acquired immunodeficiency syndrome-associated lymphoma AS283 showed no significant response when flavopiridol was used in advanced s.c. tumors, but when treatment was initiated in early stages, there was a complete regression of the early tumors, and a significant overall growth delay (>84%). When flavopiridol was used in severe combined immunodeficient mice bearing disseminated human acute lymphoblastic leukemia Nalm/6 cells, there was 15-day prolongation in survival (P = .0089). We conclude that flavopiridol greatly influences apoptosis in both normal and malignant hematopoietic tissues. This activity was manifested in our study as a potent antileukemia or antilymphoma effect in human tumor xenografts, which was dose and schedule dependent. These findings provide compelling evidence for the use of flavopiridol in human hematologic malignancies.

Polyploidy in Angiosperms: Monocotyledons

Abstract: Several different estimates of polyploid frequency in angio-sperms have been made, including G.L. Stebbins’ (1,2) figure, first published in 1950, of 30–35%, and suggestions by M.J.D. White in 1942 (3) of at least 40%, and by Grant in 1963 (4) of 47%. These figures represent different ways of calculating Polyploidy and different interpretations of the meaning of the word in the context of plant systematics. Stebbins’ estimate includes as polyploid those species which have gametic chromosome numbers that are multiples of the basic diploid number found in their genus, in other words, intrageneric Polyploidy. White’s figure is based on the simple observation that even haploid numbers exceed odd by about 40% and he thus assumed this 40% to be largely attributable to a polyploid origin. Grant postulated that species with haploid numbers in excess of n=13 would mainly be polyploid and those with n=13 or less, predominantly diploid. Grant’s study also included the only estimate I have encountered of Polyploidy in each of the two subclasses of angiosperms. He calculated a frequency of 43% in Dicotyledonae and a much higher 58% in Monocotyledonae. These figures were based on chromosome data accumulated by 1955 for some 17,138 species.

Andrographis paniculata (Burm. f.) Wall. ex Nees: a review of ethnobotany, phytochemistry, and pharmacology.

Abstract: As aboriginal sources of medications, medicinal plants are used from the ancient times. Andrographis paniculata is one of the highly used potential medicinal plants in the world. This plant is traditionally used for the treatment of common cold, diarrhoea, fever due to several infective cause, jaundice, as a health tonic for the liver and cardiovascular health, and as an antioxidant. It is also used to improve sexual dysfunctions and serve as a contraceptive. All parts of this plant are used to extract the active phytochemicals, but the compositions of phytoconstituents widely differ from one part to another and with place, season, and time of harvest. Our extensive data mining of the phytoconstituents revealed more than 55 ent-labdane diterpenoids, 30 flavonoids, 8 quinic acids, 4 xanthones, and 5 rare noriridoids. In this review, we selected only those compounds that pharmacology has already reported. Finally we focused on around 46 compounds for further discussion. We also discussed ethnobotany of this plant briefly. Recommendations addressing extraction process, tissue culture, and adventitious rooting techniques and propagation under abiotic stress conditions for improvement of phytoconstituents are discussed concisely in this paper. Further study areas on pharmacology are also proposed where needed.

Polyploidy in Angiosperms: Dicotyledons

Abstract: As summarized by Goldblatt (1) in the previous article, “Polyploidy in angiosperms: monocotyledons,” recent estimates of polyploid frequency among angiosperms vary from 30–35% to 47%. The highest value is based on the postulation that haploid numbers in excess of n=13 would be mainly polyploid and those with n=13 or less would be predominantly diploid (2). On this basis 43% of dicotyledons and 58% of monocotyledons from a sample of 17,138 species were considered polyploid. Goldblatt (1) believes, however, that limiting Polyploidy to haploid numbers over n=13 is too conservative and that at least species with numbers of n=ll and above have Polyploidy in their evolutionary history, and perhaps also many of those with n=10 and n=9 may be aneuploid derivatives of ancestors with higher numbers. He suggests that at least 70% and most likely above 80% of monocotyledons are in some sense polyploid.