Pius S,Padayatti; Paulose,C S(Department of Biotechnolgy, April 2, 1999)
[+]
[-]
Abstract:
The brain stems (13S) of streptozotocin (STZ)-diabetic rats were studied lo see the changes in
neurotransmitter content and their receptor regulation. The norepinephrine (NE) content
determined in the diabetic brain stems did ^ control. an E showed la
while
PI turnover
hri
content increased significantly compared N^r eNveFa o the recep
significant increase. The alpha2 adrenergic receptor
IneP utisoulinntreat d ratsetheNE contentt dec^ sled
was significantly reduced during diabetes. in
versedcto reanorm
sed
ulcrea e tK
reatment
the
state.
while EPI content remained increased as in die diabetic
B,, for a]pha2 adrenergic receptors slw^nificantly while
Unlabelled clonidine inhibited [31-I]NE binding in BS of control, diabetic and insulin treated
ulations bindi
diabetic rats showed that alpha2 adrenergicre^ punks cojnidiabetic animal the ligand bound
sites with Hill slopes significantly away from unity.
weaker to the low affinity site than in controls. Insulin treatment reversed[ this allumbmn to
control levels. The displacement analysis using (-)-epinephrine age in
control and diabetic animals revealed two populations of receptor affinidtyo=tat ss. In control
animals, when GTP analogue added with epinephrine, the curve nagnlde caofnfitnroit yS
model; but in the diabetic BS this effect `not
aobserved. In
bintact
oth the diabetic
data thus showlthat
the effects of monovalent cations on affinity
alphaz adrenergic receptors have a reduced affinity v
due
in stem ialtered Itscppeomson(5-
regulation. The serotonin (5-HT) coat
hydroxy) tryptophan (5-HTP) showed an increase and its breakdown metabolite (5-hydroxy)
indoleacetic acid (5-I{IAA) showed a significant decrease. This showed that in serotonergic
which l
nerves there is a disturbance in both synthetic and breankduomwnbers pretma'med ana
increased 5-HT. The high affinity serotonin receptor um ese serotonerg
decrease in the receptor affinity. The insulin ^treatmentsturtiy showsha decreased serotonergic
receptor kinetic parameters to control level.
receptor function. These changes in adrenergic and serotonergic receptor function were
suggested to be important in insulin function during STZ diabetes.
Girish Kumar, K; Chowdary, K P R; Devala Rao, G(Indian Journal Of Pharmaceutical Sciences, January 8, 1999)
[+]
[-]
Abstract:
Two simple and sensitive spectrophotometric methods (A and B)in the visible region have been developed for the determination of nimesulide in bulk and in dosage forms.Method A is based on the reaction of reduced nimesulide with nitrous acid followed by its coupling with phloroglucinol to yield an yellow colored azo dye with an absorption maximum of 400 nm and method B is based on the reaction of reduced nimesulide with p-dimethylamino benzaldehyde(PDAB) to form an yellow colored chromogen wiht an absorption maximum of 415 nm.When pharmaceutical preparations (Tablets and suspension) were analysed, the results obtained by the proposed methods are in good agreement with the labelled amounts and are comparable with the results obtained by a reported method.recovery in both the method is 98-101 %.
Sugunan, S; Bindhu, Jacob(Indian Journal of Chemistry, October , 1999)
[+]
[-]
Abstract:
The acidity of the various rare-earth exchanged zeolite-Y
catalysts has been examined by titration method using Hammett
indicators and is correlated with the catalytic activity of the
samples in the benzylation of 0-xylene.
Sugunan, S; Seena, C R Kumaree(Indian Journal of Chemistry, November , 1999)
[+]
[-]
Abstract:
The changes in surface acidity/basicity and catalytic activity of cerium oxide due to surface modification by sulphate ion have been
investigated. Electron donor properties of both the modified and unmodified oxides have been studied using electron acceptors of
various electron affinity values, viz. 7,7,8,8-tetracyanoquinodimethane, 2,3,5,6-tetrachloro--l, 4-benzoquinone. p-dinitrobenzene and
m-dinitrobenzene in order to find out whether the increase in acidity on suphation is due to the generation of new acidic sites or they are
formed at the expense of some of the basic sites. The surface acidity/basicity has been determined using a set of Hammett indicators.
The data have been correlated with the catalytic activity of the oxides for esterification of acetic acid using l-butanol, reduction of
cyclohexanone with 2- propanol and oxidation of cyclohexanol using benzophenone.
Sreekumar, K; Raja, T; Kiran, B P; Sugunan, S; Rao, B S(Elsevier, 1999)
[+]
[-]
Abstract:
The reaction of aniline with methanol was carried out over Zn1-xNixFe2O4 (x= 0, 0.2, 0.5, 0.8 and 1) type systems in a
fixed-bed down-flow reactor. It was observed that systems possessing low ``x'' values are highly selective and active for mono
N-alkylation of aniline leading to N-methyl aniline. Selectivity for N-methyl aniline over ZnFe2O4 was more than 99% under
the optimized reaction conditions. Even at methanol to aniline molar ratio of 2, the yield of N-methyl aniline was nearly
55.5%, whereas its yield exceeded 67% at the molar ratio of 7. The Lewis acid sites of the catalysts are mainly responsible for
the good catalytic performance. Cation distribution in the spinel lattice influences their acido-basic properties, and hence,
these factors have been considered as helpful to evaluate the activity and stability of the systems.
Indic, P; Pratap, R; Nampoori, V P N; Pradhan, N(International Journal of Neuroscience, 1999)
[+]
[-]
Abstract:
We propose to show in this paper, that the time series obtained from biological systems such as human brain are invariably nonstationary because of different time scales involved in the dynamical process. This makes the invariant parameters time dependent. We made a global analysis of the EEG data obtained from the eight locations on the skull space and studied simultaneously the dynamical characteristics from various parts of the brain. We have proved that the dynamical parameters are sensitive to the time scales and hence in the study of brain one must identify all relevant time scales involved in the process to get an insight in the working of brain.
Jyothi, T M; Rao, B S; Sugunan, S; Sreekumar, K(Indian Journal of Chemistry, December , 1999)
[+]
[-]
Abstract:
Alkylation of phenol with methanol has been carried out over
Sn-La and Sn-Sm mixed oxides of varying compositions at 623 K
in a vapour phase flow reactor. It is found that the product
selectivity is greatly influenced by the acid-base properties of the
catalysts. Ortho-cresol formation is favoured over catalysts with
weak acid sites whereas formation of 2,6-xylenol occurs in the
presence of stronger acid sites. The cyclohexanol decomposition
reaction and titrimetric method using Hammett indicators have
been employed to elucidate the acid-base properties of the
catalysts.
Description:
Indian Journal of Chemistry
Vol. 38A, December 1999, pp. 1253-1255