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Biomedical subjects

C P Malik

Publications and source records attributed to C P Malik.

At least 19 recordsLinked to original sources
PubMed2006

Micropropagation: a tool for the production of high quality plant-based medicines.

Medicinal plants are the most important source of life saving drugs for the majority of the world's population. The biotechnological tools are important to select, multiply and conserve the critical genotypes of medicinal plants. Plant tissue culture techniques offer an integrated approach for the production of standardized quality phytopharmaceutical through mass-production of consistent plant material for physiological characterization and analysis of active ingredients. Micropropagation protocols for cloning of some medicinal plants such as Catharanthus roseus (Apocynaceae), Chlorophytum borivilianum (Liliaceae), Datura metel (Solanaceae), and Bacopa monnieri (Scrophulariaceae) have been developed. Regeneration occurred via organogenesis and embryogenesis in response to auxins and cytokinins. The integrated approaches of our culture systems will provide the basis for the future development of novel, safe, effective, and high-quality products for consumers.

Biotechnology↗
PubMed1979

Studies on the physiology of pollen and pollen tube growth. IV Eschscholtzia californica Cham.

Eschscholtzia californica stigmas with germinating pollen at different stages of development were the subject of histochemical studies which aimed the localization of several enzymes like phosphorylase, leucine amino peptidase, nonspecific esterase, cytochrome oxidase, aldolase, alpha-glycerophosphate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, monoamine oxidase, alpha-galactosidase, beta-glucosidase and beta-galactosidase. Pollen and pollen tubes were shown to contain starch, lipid, proteins and soluble sugars as the storage products. These storage products were utilized during germination and tube growth. The role of different enzymes in the process of germination and tube growth is discussed. From the distribution of oxidoreductases it is inferred that respiration plays an essential role in the tube growth. During pollen germination probably the reserve proteins were transported to pollen tube tip. The increase of activity of alpha-and beta-galactosidase in pollen tubes indicates on their involvement in carbohydrate metabolism. The role of alpha-galactosidase in the metabolism of galactolipids is also inferred. Similarly, the reaction catalysed by beta-glucosidase resulted in the production of aglycon and glucose; of these the former possibly act as a substrate of peroxidase. Some of the glycosidases diffused out of pollen wall on the stigma and participated in the release of free sugars of the female tissue.

Electron Transport Complex IV↗
PubMed1977

Histochemical studies in stomatal apparatus of Phaseolus mungo Linn, Lathyrus sativus Linn and Opuntia elatior Mill.

With histochemical methods the distribution of some enzymes and metabolic substances in the epidermal peelings of Phaseolus mungo, Lathyrus sativus, and Opuntia elatior under light and dark conditions is examined. Dehydrogenases oxidases, transferases and hydrolases were studied. Fluctuations in the activity of hydrolases, especially, acid phosphatase, lipase, glucose-6-phosphatase, adenosine triphosphatase, dehydrogenases and transferases were observed during light and dark conditions. The role of such fluctuations in relation to stomatal regulation is discussed. Based on the present studies the following is suggested; stomatal opening and closing is related to structural and metabolic changes, and these changes are brought about by sugar gradients in the guard cells; light is enhancing the synthesis of sugars and some hormones, and besides this it stimulates membrane bound adenyl cyclase and release of cyclic AMP which affects the permeability; subsidiary cells actively participate in the stomatal physiology. Lysosomal hydrolytic enzymes like acid phosphatase are actively involved in catabolic phase of normal guard cells metabolism and regulate the osmotic pressure of the guard cells.

Ascorbic Acid↗
PubMed1976

Studies on the physiology of pollen and pollen tube growth. 1. pinus roxburghii.

Pollen grains and pollen tubes of Pinus roxburghii were subjected to histochemical technique with a view to determining the distributional pattern of reserve substances (ascorbic acid, proteins starch, polysaccharides, nucleic acids) and some enzymes (acid phosphatase, glucose-6-phosphatase, peroxidase, esterase, cytochrome oxidase, succinate dehydrogenase). An attempt is made to correlate the activity of different enzymes in relation to pollen tube growth.

Enzymes↗
PubMed1976

Gingivitis and periodontal disease in pregnancy.

Forty pregnant women in each of three trimesters of pregnancy and forty nonpregnant women of comparable age, socioeconomic status and dietary habit have been examined to evaluate the gingival condition and the calculus and debris deposits. The study has shown that: There is a significant increase in the severity of gingivitis during pregnancy; The gingival changes progressively increase during the course of pregnancy; The gingival changes are more marked than the periodontal changes seen during pregnancy (increase in periodontal disease was seen in only a limited number of cases); There was an appreciable increase in the calculus and debris deposits in the pregnant as compared to the nonpregnant women; Increase in the calculus and debris deposits was apparent in all the trimesters of pregnancy; Gingival changes showed a greater correlation with the calculus and the debris index in the pregnant than in the nonpregnant women; The role of the irritant oral deposits either as a precipitating or perpetuating factor in the genesis of gingivitis during pregnancy can not be excluded.

Dental Calculus↗
PubMed1976

Histochemical studies on reserve substances and enzymes in female gametophyte of Zea mays.

Cytochemical changes during the early development of maize caryopsis are reported. Changes in the localization of different reserve substances (e.g. polysaccharides, proteins, nucleic acids and lipids) and enzymes (acid phosphatase, esterase, lipase, phosphorylase, succinate dehydrogenase, cytochrome oxidase and peroxidase) have been studied in unfertilized and fertilized ovules. Before pollination very feeble enzyme activity (acid phosphatase, succinate dehydrogenase, cytochrome oxidase and peroxidase) was observed. Reserve substances were present in low amounts before pollination. Pollination stimulated the accumulation of several substances and enzymes in the tip of the nucellus, micropylar zone. Just prior to, during and after fertilization, the cells in the micropylar zone had strong reaction for several enzymes indicating temporary enhancement of metabolic activity in the micropylar zone. The role of antipodals in the storage of reserve food products and nutrition of embryo and early stages of endosperm development is discussed. The pattern of enzymatic changes within the embryo sac reflected the biochemical changes operative during quiescent and active stages. The nucellus of Zea mays contains many enzymes required for hydrolysis of reserved food substances. A role of acid phosphatase in autolysis of nucellar cells, after fertilization is suggested. Post-fertilization increase in the activity of enzymes and accumulation of reserve materials is interpreted as reflecting a presumed increase in the metabolic rate relative to growth and differentiation.

Acid Phosphatase↗
PubMed1976

III. Histochemical characteristics of suspensor during embryo development in Brassica campestris Linn. var., Sarson.

The development of suspensor in Brassica campestris is of the "Onagrad type"; The suspensor growth was maximum between the globular and heart stage of embryo development. There after, the suspensor diminished and immediately after the torpedo stage, it degenerated several enzymes (e.g. acid-, alkaline-, adenosine triphosphatase, peroxidase, succinate dehydrogenase, cyotchrome oxidase) and general substances (ascorbic acid, polysaccharides, lipids) were localized in the suspensor during different phases of embryo growth. Between the globular and heartshaped stage, suspensor cells had strong reaction. An attempt is made to elucidate possible physiological functions in relation to specific enzyme localization. The possibility of suspensor having secretory function is also brought out. Present histochemical data indicated that suspensor was chiefly concerned with absorption and transport of metabolites from the surrounding tissue to the developing embryo.

Histocytochemistry↗
PubMed1975

Periapical actinomycosis.

Two cases of actinomycotic lesions of the periapical tissue in relation to the molars are described. The difficulty in obtaining a positive culture for actinomycetes in spite of definite histologic evidence of actinomycosis is highlighted. Besides antibiotics, the importance of planned treatment to deal with the underlying diseased periapical tissue and the tooth is emphasized.

Actinomycosis, Cervicofacial↗
PubMed1975

Histochemical studies in stomatal apparatus of Phaseolus mungo Linn. I. Localization of enzymes and structural material.

In the present investigations, the localization of several enzymes (Acid Phosphatase, Peroxidase, succinic dehydrogenase, Phosphorylase, alkaline phosphatase, ATP-ase) and other substances in the guard and subsidiary cells as well as trichomes of the leaves of Phaseolus mungo, was carried out. Attempts were also made to follow the sequence of developmental stages starting with meristemoids and culminating in differentiated structures. The basic information thus obtained is used in interpreting the developmental physiology of stomatal differentiation as well as their cellular organisation. Histochemical observations made in the present studies are compared with the electron microscopical observations of Whatley (1972). It is proposed that mitochondria played a basic role in the functioning of the guard cells. The present studies also demonstrated activity of acid phosphatase in the guard cells and was localized in spherosomes. The latter varied in the activity for acid phosphatase and was dependent on the turgid level of the cell. Interestingly, enough localization of phosphatase could only be observed in spherosomes when the osmotic pressure in the cell was relatively low, once the osmotic pressure increased, the activity disappeared.

Acid Phosphatase↗
PubMed1975

Histochemical studies in stomatal apparatus of Phaseolus mungo linn. IV. Mechanism of stomatal action.

The histochemical studies were carried out in the open and closed stomata of Phaseolus mungo leaves. Several enzymes like, Acid phospatase peroxidase, succinic dehydrogenase, phosphorylase, alkaline phosphatase, ATP-ase etc. were localized in the guard and subsidiary cells of epidermal peel. On the basis of cytochemical localization, enzyme activity was precisely interpreted. In the light of fluctuations in the localization, activities of different enzymes, an attempt is made to provide the functional interpretation of stomatal mechanism. We have attempted to correlat our observations in relation to diurnal metabolisms. Our studies suggest that starch-sugar inter-changes played a vital role in the stomatal regulation. We are also inclined to believe that besides guard cells, subsidiary cells also influenced the turgid conditions. A model based on available facts in collaboration with our own studies is presented which tends to explain the stomatal regulation.

Acid Phosphatase↗
PubMed1975

Histochemical studies in stomatal apparatus of Phaseolus mungo Linn. II. Localization of phosphorylase.

Using histochemical techniques the presence of phosphorylase in the guard cells and subsidiary cells of Phaseolus mungo leaf has been demonstrated. The intensity of reaction is intense in the material collected at night while during the day collected leaves, both chloroplastic and cytoplasmic starch was absent. The functional significance of chloroplastic starch in the subsidiary cells in relation to the stomatal mechanism is discussed.

Chloroplasts↗
PubMed1975

Physiology of sexual reproduction. I. A histochemical study of the embryo sac development in Zephyranthes rosea and Lagenaria vulgaris.

Using histochemical techniques, changes in the localization of different reserve substances (e.g. pectic compounds, starch, polysaccharides, proteins, nucleic acids, ascorbic acid) and enzymes (Acid phosphatase, alkaline phosphatase, ATP-ase, 5-nucleotidase, esterase, phosphorylase, succinate dehydrogenase, cytochrome oxidase and lipase) have been studied in the young and fertilized ovules of Zephyranthes sp. and Lagenaria sp. etc. Extensive changes in the enzyme activity and reserve substances are demonstrated during megasporogenesis and megagametogenesis and most of the substances exhibited interesting distributional pattern. Similarly, all the enzymes investigated have specific locale of distribution in the tissues which displayed differentiation of embryo sac. The earlier changes observed are in the megaspore which contained many reserve substances (starch; nucleic acids; ascorbic acid; proteins) and enzymes (peroxidase, succinate dehydrogenase, acid phosphatase, alkaline phosphatase and ATP-ase). In the matured embryo sac different cells have differential localization of the substances. Based on histochemical studies, distinct differences are made out between egg and synergids; egg and central cell. In general antipodals have maximum accumulation of physiologically active substances and intense activity of different enzymes. Nucellus cells also stored diverse substances and enzymes especially towards the chalazal end. Pollination stimulated accumulation of several reserve substances and enzymes in the tip of nucellus beak, micropylar zone and these included starch, peroxidase, phosphorylase succinate dehydrogenase, cytochrome oxidase etc.

Blastocyst↗