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The Role of PPARgamma in the Cyclooxygenase Pathway in Lung Cancer.
Decreased expression of peroxisome proliferator activated receptor-gamma (PPARgamma) and high levels of the proinflammatory enzyme cyclooxygenase-2 (COX-2) have been observed in many tumor types. Both reduced (PPARgamma) expression and elevated COX-2 within the tumor are associated with poor prognosis in lung cancer patients, and recent work has indicated that these signaling pathways may be interrelated. Synthetic (PPARgamma) agonists such as the thiazolidinedione (TZD) class of anti-diabetic drugs can decrease COX-2 levels, inhibit growth of non-small-cell lung cancer (NSCLC) cells in vitro, and block tumor progression in xenograft models. TZDs alter the expression of COX-2 and consequent production of the protumorigenic inflammatory molecule prostaglandin E2 (PGE2) through both (PPARgamma) dependent and independent mechanisms. Certain TZDs also reduce expression of PGE2 receptors or upregulate the PGE2 catabolic enzyme 15-prostaglandin dehydrogenase. As several COX-2 enzymatic products have antitumor properties and specific COX-2 inhibition has been associated with increased risk of adverse cardiac events, directly reducing the effects or concentration of PGE2 may provide a more safe and effective strategy for lung cancer treatment. Understanding the mechanisms underlying these effects may be helpful for designing anticancer therapies. This article summarizes recent research on the relationship between (PPARgamma), TZDs, and the COX-2/PGE2 pathways in lung cancer
On some generalized ageing orderings
Some partial orderings which compare probability distributions with the expo-
nential distribution, are found to be very useful to understand the phenomenon
of ageing. Here, we introduce some new generalized partial orderings which de-
scribe the same kind of characterization of some generalized ageing classes. We
give some equivalent conditions for each of the orderings. Inter-relations
among the generalized orderings have also been discussed
Ice storage characteristics of cultured silver carp
Cultured silver carp (Hypopthalmichthys molitrix 800-1000 g) was stored in ice (fish to ice ratio 1:1) in a plywood box insulated with one inch thick expanded polystyrene and subjected to detailed examination of quality by chemical, microbiological and organoleptic evaluation at regular intervals to assess the storage life in good acceptable form. Alpha-amino nitrogen, non-protein nitrogen and pH values showed no positive correlation as spoilage index. Total volatile base nitrogen was not high at the end of the storage period although the fish became unacceptable during the period. There was steep decrease in total bacterial count during initial stages of storage and then increased steadily on further storage. Organoleptic evaluation of raw and cooked meat revealed that fish was in good acceptable form up to 14 days in ice
The bacterium, Staphylococcus aureus induced chromosome aberrations with their protection by penicillin, and mitotic inhibition in Syrian hamsters
The frequency of bone marrow chromosome aberrations in Syrian hamster, Mesocricetus auratus induced by the injection of log culture, saline suspension and culture filtrate of S. aureus was significantly high while the treatment of heat-killed bacterial suspension showed no difference with control data. In the first three treated series aberrations were of individual and gross types while others had only individual types. The chromatid breaks were nonrandom, the centro-meric region being less vulnerable and the distal region was more susceptible. The aberration frequency was significantly reduced when log culture, saline suspension and culture filtrate treated specimens were also injected with penicillin 1 hr before simultaneously and 1 hr after, of which the post-treatment rendered the maximum protection. Lastly, the treatment of isolated bacterial sample retarded the mitotic frequency significantly as compared to that of normal and controls
Normal ordering and non(anti)commutativity in open super strings
Nonanticommutativity in an open super string moving in the presence of a
background antisymmetric tensor field is investigated
in a conformal field theoretic approach, leading to nonanticommutative
structures. In contrast to several discussions, in which boundary conditions
are taken as Dirac constraints, we first obtain the mode algebra by using the
newly proposed normal ordering, which satisfies both equations of motion and
boundary conditions. Using these the anticommutator among the fermionic string
coordinates is obtained. Interestingly, in contrast to the bosonic case, this
new normal ordering plays an important role in uncovering the underlying
nonanticommutative structure between the fermionic string coordinates. We feel
that our approach is more transparent than the previous ones and the results we
obtain match with the existing results in the literature.Comment: Comments 10 pages latex, accepted for publication in Physical Review
Noncommutativity in interpolating string: A study of gauge symmetries in noncommutative framework
A new Lagrangian description that interpolates between the Nambu--Goto and
Polyakov version of interacting strings is given. Certain essential
modifications in the Poission bracket structure of this interpolating theory
generates noncommutativity among the string coordinates for both free and
interacting strings. The noncommutativity is shown to be a direct consequence
of the nontrivial boundary conditions. A thorough analysis of the gauge
symmetry is presented taking into account the new modified constraint algebra,
which follows from the noncommutative structures and finally a smooth
correspondence between gauge symmetry and reparametrisation is established.Comment: 14 pages Late
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