Virinder,Moudgil; Vera,Kruczak; Thomas,Eessalu; Paulose,C S; Michael,Taylor; Jeffrey,Hansen(Department of Biotechnology, May 14, 1981)
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Abstract:
Progesterone-receptor complex from freshly prepared hen oviduct cytosol acquired the ability to bind to
isolated nuclei, DNA-cellulose and ATP-Sepharose when incubated with 5-10 mM ATP at 4°C. The extent of
this ATP-dependent activation was higher when compared with heat-activation achieved by warming the progesterone-
receptor complex at 23 °C. The transformation of progesterone-receptor complex which occurred in a
time-dependent manner was only partially dependent on hormone presence. The ATP effect was selective in
causing this transformation whereas ADP, AMP and cAMP failed to show any such effect. The non-hydrolizable
analogs of ATP, adenosine 5'-[a,/3-methylene]triphosphate and adenosine 5-[/l,y-imido]triphosphate were also
found to be ineffective. Presence of 10 mM sodium molybdate blocked both the ATP and the heat-activation of
progesterone-receptor complex. Mn" or Mg` had no detectable effect on the receptor activation but the presence
of Ca" increased the extent of ATP-activation slightly. EDTA presence (> 5 mM) decreased the extent of
receptor activation by about 40 % and was, therefore, not included in the buffers used for activation studies.
Divalent cations were also ineffective when tested in the presence of 1- 5 mM EDTA. The
properties of progesterone-receptor complex remained intact under the above conditions when analyzed for
steroid-binding specificity and Scatchard analysis. However, the ATP-activated progesterone-receptor complex
lost the ability to aggregate when tested on low-salt sucrose gradients. ATP was equally effective in activating
the rat-uterine estradiol-receptor complex at 4 "C and influenced the transformation of 4-S receptor form into
a 5-S form when analyzed on sucrose gradients containing 0.3 M KCI. The presence of ATP also increased the
rate of activation of progesterone-receptor complex at 23 °C. These findings suggest a role for ATP in receptor
function and offer a convenient method of studying the process of receptor activation at low temperature and
mild assay conditions.
Rani, Joseph(Huthig & Wepf Verlag, Basel, April 29, 1986)
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Abstract:
Tribasic lead sulphate is tried as a practical curing agent for polychloroprene. The
cure characteristics of the compounds as well as the technical properties of the
vulcanizates show that it can act as a potential curative.
Rani, Joseph(Hitthig & Wepf Verlag, Basel, October 13, 1986)
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Abstract:
A carbon black filled 50/50 natural rubber (NR)/styrene-butadiene rubber (SBR)
blend is vulcanized using several conventional curing systems designed by varying the
amounts of sulphur and accelerator. The cure characteristics and the properties of the
vulcanizates are compared. The quantity and quality of crosslinks in each case are
evaluated by chemical probes to correlate them with the properties.
Rani, Joseph(Gordon and Breach Science Publishers, Inc., November 13, 1986)
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Abstract:
A carbon black filled 50/50 Natural Rubber (NR)/Polybutadiene Rubber (BR) blend
is vulcanized using several conventional systems designed by varying the amounts of
sulphur and accelerator . The cure characteristics and the vulcanizate properties are
compared. The quality and quantity of crosslinks in each case are deciphered by
chemical probes to correlate them with the vulcanizate properties.
Blends of 50/50 natural rubber (NR) and styrene-butadiene rubber (SBR) are vulcanized using
several conventional and semi-EV systems. The cure characteristics and vulcanizate properties
are compared. The quantity and quality of crosslinks in each case are deciphered by chemical
probes to correlate them with the vulcanizate properties.
Dakshinamurti,K; Paulose,C S(Department of Biotechnology, May , 1983)
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Abstract:
The concentrations of serotonin in various brain areas were significantly decreased in
the pyridoxine-deficient young rat.
2. There was no change in the concentration of dopamine.
3. Both Bmax and Kid of [3H]serotonin binding to membrane preparations from cerebral cortex
were increased in deficiency and were restored to normal upon pyridoxine supplementation.
4. There was no change in [3H]spiroperidol binding to corpus striatal membrane preparations
in pyridoxine-deficient rats.
Dakshinamurti,K; Paulose,C S; Siow,Y L(Department of Biotechnology, 1985)
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Abstract:
Pyridoxal 5'-phosphate (PLP) is the major coenzymatic
form of pyridoxine. There are over one hundred known pyridoxal
5'-phosphate-dependent reactions, most of which are
involved in the metabolism of various amino acids . Pyridoxamine
5'-phosphate can function in aminotransf erase reactions
by the cyclic regeneration of the two active phosphate
forms. Pyridoxal 5'-phosphate-dependent reactions studied
in the nervous system are involved in the catabolism of various
amino acids. The putative neurotransmitters , dopamine,
norepinephrine , serotonin , histamine , aminobutyric acid
and taurine , as well as the sphingoiipids and poly amines are
synthesized by PLP-dependent enzymes. Of these enzymes,
three ( glutamic acid decarboxylase , 5-hydroxytryptophan decarboxylase
and crnithine decarboxylase) seem to have crucial
roles (Fig. '). The clinical effects of pyridoxine deficiency
can be explained on the basis of the known decreases
in the activities of these enzymes
Dakshinamurti,K; Paulose,C S; Thliveris,J A; Vriend,J(Department of Biotechnology, August 15, 1984)
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Abstract:
In pyridopaminedoxine-deficient young rats hypothalamic serum TSH concentration was detected. Highly signifiserotonin
was decreased with no changes in the cant decreases in the content of pituitary TSH and in
and noradrenaline content. Serum the number of pituitary thyrotroph secretory granules
and tri-iodothyronine concentrations were were found. These results suo
mmuuchch lower in the deficient rats as compared to thyroidism of suggest that the hypocontrols.
No significant of hypothalamicp yorirdigoxinin.e -deficient young rats might bbee
difference between deficient and control groups in the
Lalitha, P R; Rao, V R; V P N Nampoori(Current Science, 1980)
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Abstract:
Excitation and emission spectra of SrS : Mn : Ce phosphors have been studied in detail
at various Mn and Ce concentrations. In order to study the effect of external pressure on phosphors,
the samples were pretreated under various pressures. Four bands around 470 nm, 530 nm,
310 nm and 620 nm were observed, when the samples were excited with 265 nm radiation. The
effect of pressure is to reduce the fluorescence ability of the phosphors, and the luminescence
vanishes above O· 1 ton m-2 pressure. The fluorescence ability, however, can be regained on retiring
the sample. The emission mechanism has been attributed to two luminescentcenters in the forbidden
gap. An appreciable amount of photocurrent has also been observed for the sample.
K G Nair; Aanandan,C K; Mohanan,P(Department of Electronics, August 13, 1984)
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Abstract:
Design and development of a circularly polarized and matched H-plane sectorial horn antenna have been reported By
proper trimming of the flange parameters any desired polarization can be obtained from the horn