Roshini K, Thumpakara; Dr. Prathapan, S(Cochin University of Science & Technology, November , 2007)
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Abstract:
The synthesis and reactions of simple derivatives of 2(3H)- and 3(2H)furanones
have attracted considerable attention in recent years, primarily in
connection with development of routes to antitumor agents that contain this
ring as central structural unit. They also serve as useful synthetic building
blocks for lactones and furans and are the precursors of a wide variety of
biologically important heterocyclic systems. Although a number of syntheses
of furanones were known they were in many cases limited to specific
substitution pattems. The development of altemative strategies for the
preparation of these heterocycles is therefore of considerable importance or
continues to be a challenge.We propose to develop new and general approaches to the synthesis of
furanone ring systems from simple and readily available starting materials
since we were interested in examining their rich photochemistry. The
photochemical reactivity of Beta,gama-unsaturated lactams and lactones is a subject of current interest. Some of the prominent photoreaction pathways of
unsaturated lactones include decarbonylation, solvent addition to double
bonds, decarboxylation, migration of aryl substituents and dimerisation. lt
was reported earlier that the critical requirement for clean photochemical
cleavage of the acyl-oxygen bond is the presence ofa double bond adjacent to
the ether oxygen and 2(3H)-furanones possessing this structural requirement
undergo facile decarbonylation. But related phenanthrofuranones are isolated
as photostable end products upon irradiation. Hence we propose to synthesis a
few phenanthro-2(3H)-furanones to study the effect of a radical stabilising
group at 3-position of furanone ring on photolysis. To explore the tripletmediated
transformations of 2(3H)-furanones in polar and nonpolar solvents a
few 3,3-bis(4-chlorophenyl)-5-aryl-3H-furan-2-ones and 3,3-di(p-tolyl)-5-aryl-
3H-furan-2-ones were synthesised from the corresponding
dibenzoylstyrene precursors by neat thermolysis. Our aim was to study the
nature of intermediates involved in these transformations.We also explored the possibility of developing a new and general
approach to the synthesis of 3(2H)-furanones from simple and readily
available starting materials since such general procedures are not available.
The protocol developed by us employs readily available phenanthrenequinone
and various 4-substituted acetophenones as starting materials and provides
easy access to the required 3(2H)-furanone targets. These furanone
derivatives have immense potential for further investigations .We also aimed the synthesis of a few dibenzoylalkene-type systems
such as acenaphthenone-2—ylidene ketones and phenanthrenone-9-ylidene
ketones. These systems were expected to undergo thermal rearrangement to
give furanones and spirofuranones. Also these systems can be categorised as
quinonemethides which are valuable synthetic intermediates.
Description:
Department of Applied Chemistry, Cochin University of Science
and Technology
Pyroja, S; Paulose, C S(Department of Biotechnology, Faculty of Science, April , 2002)
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Abstract:
The work is an attempt to understand the role of 5-HT, 5-HT1A and 5-HT2C receptors in the regulation of liver cell proliferation using in vivo and in vitro models. The work also focuses on the brain serotonergic changes associated with hapatocyte proliferation and apoptosis to delineate its regulatory function. The investigation of mechanisms involving different models of hepatocyte proliferation contributes to our knowledge about serotonergic regulation of cell growth, apoptosis and carcinogenesis of liver. The study reveals that the alteration of the 5-HT1A and 5-HT2C receptor function and gene expression in the brain stem, cerebral cortex and hypothalamus play an important role in the sympathetic regulation of cell proliferation, neoplastic transformation and apoptosis. The functional balance between 5-HT1A and 5-HT2C receptor plays an important role in regulating hepatocyte proliferation, neoplastic transformation and hepatic apoptosis. The regulatory role of 5-HT1A and 5-HT2C receptor during neoplastic transformation and apoptosis could lead to possible therapeutic intervention in the treatment of cancers and have immense clinical importance.
Jasmine, Mathew; Dr. Ebenezer, D D(Defence Research and Development Organisation, September , 2011)
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Abstract:
New mathematical methods to analytically investigate linear acoustic radiation
and scattering from cylindrical bodies and transducer arrays are presented. Three
problems of interest involving cylinders in an infinite fluid are studied. In all the three
problems, the Helmholtz equation is used to model propagation through the fluid and the
beam patterns of arrays of transducers are studied.
In the first problem, a method is presented to determine the omni-directional and
directional far-field pressures radiated by a cylindrical transducer array in an infinite
rigid cylindrical baffle. The solution to the Helmholtz equation and the displacement
continuity condition at the interface between the array and the surrounding water are
used to determine the pressure. The displacement of the surface of each transducer is in
the direction of the normal to the array and is assumed to be uniform. Expressions are
derived for the pressure radiated by a sector of the array vibrating in-phase, the entire
array vibrating in-phase, and a sector of the array phase-shaded to simulate radiation
from a rectangular piston. It is shown that the uniform displacement required for
generating a source level of 220 dB ref. μPa @ 1m that is omni directional in the
azimuthal plane is in the order of 1 micron for typical arrays. Numerical results are
presented to show that there is only a small difference between the on-axis pressures
radiated by phased cylindrical arrays and planar arrays. The problem is of interest
because cylindrical arrays of projectors are often used to search for underwater objects.
In the second problem, the errors, when using data-independent, classical, energy
and split beam correlation methods, in finding the direction of arrival (DOA) of a plane
acoustic wave, caused by the presence of a solid circular elastic cylindrical stiffener near
a linear array of hydrophones, are investigated. Scattering from the effectively infinite
cylinder is modeled using the exact axisymmetric equations of motion and the total
pressures at the hydrophone locations are computed. The effect of the radius of the
cylinder, a, the distance between the cylinder and the array, b, the number of
hydrophones in the array, 2H, and the angle of incidence of the wave, α, on the error in
finding the DOA are illustrated using numerical results. For an array that is about 30
times the wavelength and for small angles of incidence (α<10), the error in finding the
DOA using the energy method is less than that using the split beam correlation method
with beam steered to α; and in some cases, the error increases when b increases; and the errors in finding the DOA using the energy method and the split beam correlation
method with beam steered to α vary approximately as a7 / 4 . The problem is of interest
because elastic stiffeners – in nearly acoustically transparent sonar domes that are used to
protect arrays of transducers – scatter waves that are incident on it and cause an error in
the estimated direction of arrival of the wave.
In the third problem, a high-frequency ray-acoustics method is presented and
used to determine the interior pressure field when a plane wave is normally incident on a
fluid cylinder embedded in another infinite fluid. The pressure field is determined by
using geometrical and physical acoustics. The interior pressure is expressed as the sum
of the pressures due to all rays that pass through a point. Numerical results are presented
for ka = 20 to 100 where k is the acoustic wavenumber of the exterior fluid and a is the
radius of the cylinder. The results are in good agreement with those obtained using field
theory. The directional responses, to the plane wave, of sectors of a circular array of
uniformly distributed hydrophones in the embedded cylinder are then computed. The
sectors are used to simulate linear arrays with uniformly distributed normals by using
delays. The directional responses are compared with the output from an array in an
infinite homogenous fluid. These outputs are of interest as they are used to determine the
direction of arrival of the plane wave. Numerical results are presented for a circular array
with 32 hydrophones and 12 hydrophones in each sector. The problem is of interest
because arrays of hydrophones are housed inside sonar domes and acoustic plane waves
from distant sources are scattered by the dome filled with fresh water and cause
deterioration in the performance of the array.
Finla, Chathu; Dr. Paulose, C S(Cochin University of Science and Technology, February , 2007)
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Abstract:
In the present work, the role of oxygen, epinephrine and glucose
supplementation in regulating neurotransmitter contents, adrenergic and glutamate
receptor binding parameters in the cerebral cortex of experimental groups of neonatal
rats were investigated. The study of neurotransmitters and their receptors in the
cerebral cortex and the EEG pattern in the brain regions of neonatal rats were taken as
index for brain damage due to hypoxia, oxygen and epinephrine. Real-Time PCR work was done to confirm the binding parameters. Second messenger, cyclic
Adenosine Monophosphate (cAMP) was assayed to find the functional correlation of
the receptors. Behavioural studies were carried out to confirm the biochemical and
molecular studies. The efficient and timely supplementation of glucose plays a crucial
role in correcting the molecular changes due to hypoxia, oxygen and epinephrine. The
addictive neuronal damage effect due to oxygen and epinephrine treatment is another
important observation. The corrective measures from the molecular study brought to
practice will lead to maintain healthy intellectual capacity during the later
developmental stages, which has immense clinical significance in neonatal care.
Description:
Department of Biotechnology, Cochin
University of Science and Technology
Ani Das, V; Paulose, C S(Department of Biotechnology, Faculty of Science, August , 2000)
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Abstract:
In the present study, the changes in the brain EPI (Epinephrine), adrenergic receptors and the receptor gene expression were investigated during pancreatic regeneration and insulin secretion. The changes in the pancreatic islet EPI and adrenergic receptors were also studied in the pancreatectomised rats. The regulatory function of EPI in association with Epidermal growth factor (EGF) and glucose were investigated in rat islet cultures. In vitro studies were carried out using antagonists for adrenergic receptor subtypes to see their involvement in the islet DNA synthesis. The mechanism by which the peripheral EPI regulate insulin secretion was also investigated by studying the nuclear binding proteins in the pancreatic islets during pancreatic regeneration and diabetes. The study reveals that EPI can regulate the pancreatic islet cell proliferation by controlling the insulin synthesis and secretion. The brain adrenergic receptor gene expression and functional correlation regulate the pancreatic adrenergic receptors. The functional balance of α and β-adrenergic receptors controls the insulin secretion and pancreatic β-cell proliferation, which will have immense clinical significance in the treatment of Diabetes mellitus.
The present study was undertaken to elucidate the nutritional and pathological changes associated with aflatoxin B1 toxicity in Penaeus monodon and to determine the efficacy of vitamins E and K, and Amrita Bindu, herbal mixture in ameliorating the toxicity of AFB1.
The main objectives the study is to document the pathological and immunological changes in P.monodon fed with AFB1 incorporated diets and to delineate the histological and ultrastructural changes and determine the presence of AFB1 residue in the shrimp body, to evaluate the growth performance of feed efficiency in P. monodon post larvae fed AFB1 added diets, to assess the interactive effect of heavy metals like copper and cadmium at sub-lethal levels in P. monodon postlarve fed AFB1 added diets, to decipher the ameliorative action of Vitamins E & K and a spicy herbal mixture, Amrita Bindu on AFB1 in P.monodon sub-adults. The study has revealed that Aflatoxin B1 significantly affects protein, lipid and carbohydrate metabolism in the shrimp penaeus monodon. The remarkable effect was observed in the immune system, as AFB1 has elevatod the immune response during initial days of exposure and prolonged exposure to the toxin leads to weakening of the animal’s immunity. Aflatoxin B1 level above 50 ppb severely affected the growth and feed utilization which in turn reflects the damage caused to the hepatopancreas as evident from the histological and ultrastructural observations.
Manjusha, K; Dr. Saramma, A V(Cochin University of Science and Technology, July , 2011)
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Abstract:
The thesis presents a detailed account of the alkaline protease produced by Vibrio sp.(V26) a mangrove isolate,and the application of this enzyme in different fields.The protease producer strain was identified on the basis of biochemical characteristice,putative virulence traits and 16S rRNA gene sequencing.The purification and characterization of the protease has been carried out. Along with this, an attempt has been made to identifiy the protease gene. The physical parameters as well as the media components influencing protease production were optimized using Response Surfce Methodology(RSM).The scale up of the application of the protease from Vibrio sp.(V26) in the dissociation of cells in animal cell culture,in the recovery of silver from used X-ray films as well as an ingredient in commercial detergents were investigated.
Description:
Dept.of Marine Biology,Microbiology and Biochemistry,Cochin University of Science and Technology