A method for in vivo [32P]phosphate labelling of testis proteins

The direct intratesticular injection of [P-32]phosphate resulted in 4-9 times more labelling of rat testis proteins compared to the conventional method of in vitro incubation. Moreover this is a simple technique requiring minimum (7-10 times less) radioactive phosphate and is less hazardous

Studies on ovarian quiescence in the lactating bonnet monkey (Macaca radiata)

Lactating bonnet monkeys were used as a model to understand the mechanism of ovarian quiescence during lactation. The ovary of the bonnet monkey in the 3rd month of lactation responds well to exogenous pregnant mare serum gonadotropin stimulation with serum estrogen values reaching maximal levels by day 3 of the gonadotropin injection. The adminstration of ovine prolactin to such monkeys significantly inhibited the ovarian responsiveness to exogenous gonadotropin. The responsiveness of the pituitary of the lactating monkey (in the 3rd month of lactation) to luteinizing hormone releasing hormone injection was suppressed and supplementation with exogenous prolactin further accentuating this effect. The relative ability of chlorpromazine given intravenously/intramuscularly/intranasally to enhance endogenous prolactin levels was assessed. During the first 5 months of lactation when the basal prolactin levels were high, the luteinizing hormone levels were low. As the suckling stimulus reduces and prolactin levels fall, luteinizing hormone levels increase, the first post-parturient mensus occurring by 218 \pm 4 days. This event was postponed by 3 months on increasing endogenous prolactin levels by administering chlorpromazine (250 \mu g/day by intranasal mode) over a 5 day period every month starting from the 3rd month of lactation

Electron-vibration coupling and its effects on optical and electronic properties of single molecules

The thesis is devoted to theoretical investigations of electron-vibration coupling and its effects on optical and electronic properties of single molecules, especially for molecules confined between metallic electrodes. A density-matrix approach has been developed to describe the photon emission of single molecules confined in the scanning tunneling microscope (STM). With this new method electronic excitations induced by both the tunneling electron and the localized surface plasmon (LSP) can be treated on an equal footing. Model calculations for porphyrin derivatives have successfully reproduced and explained the experimentally observed unusual variation of the photon emission spectra. The method has also been extended to study the STM induced fluorescence and phosphorescence of C60 molecules in combination with the first principles calculations. In particularly, the non-Condon vibronic couplings have been exclusively included in the calculations. The experimental spectra have been nicely reproduced by our calculations, which also enable us to identify the unique spectral fingerprint and origin of the measured spectra. The observed rich spectral features have been finally correctly assigned. The electron transport properties of molecular junctions with bipyridine isomers have been studied in the sequential tunneling (SET) regime by assuming that the molecules are weakly coupled to metallic electrodes. It is shown that the strong electron-vibration coupling in the 2, 2’-bipyridine molecule and the 4,4’-bipyridine molecule can lead to observable Franck-Condon blockade. Taking advantage of such novel effect, a gate-controlled conductance switch with ideal on-off ratio has been proposed for a molecular junction with the 4, 4’-bipyridine molecule. The effect of the electron-vibration coupling on one-photon and two-photon absorption spectra of green fluorescent protein (GFP) has been systematically examined. The hydroxybenzylidene-2, 3-dimethylimidazolinone molecule in the deprotonated anion state (HBDI−) is used to model the fluorescence chromophore of the GFP. Both Condon and non-Condon vibronic couplings have been considered in the calculations. The calculated spectra are in good agreement with the available experimental spectra. It confirms the notion that the observed blue-shift of the two-photon absorption spectrum with respect to its one-photon absorption counterpart is caused by the non-Condon vibronic coupling. All the calculations are carried out with our own software package, DynaVib. It is capable of modeling a variety of vibrational-resolved spectroscopies, such as absorption, emission, and resonant Raman scattering (RRS) spectra. In our package, the Duschinsky rotation and non-Condon effect have been fully taken into account. Both time-independent and time-dependent approaches have been implemented, allowing to simulate the spectra of very large molecules.QC 20130520</p

Preventing Tobacco Use Among Young People in India: Project MYTRI

Objectives. We assessed the effectiveness of a 2-year multicomponent, school-based intervention designed to reduce tobacco use rates among adolescents in an urban area of India