Seasonal trend in movement directions at dawn and dusk: a study on crow and white herons

Crows (Corvus splendens) and white herons (Ardea alba) inhabit the agricultural landscapes nearby human habitats which represent dynamic ecosystem and show seasonal crop patterns. We studied the movement pattern in these birds at dawn and dusk, during solstices (December and June) and equinoxes (March and September). The movement directions were changed from uniform at dawn to a concentrated distribution at dusk all along the season suggesting that morning movements are more exploratory than evening with seasonal differences. Differential use of directions in December than June could be the effect of temperature, food availability or wind direction and speed. During breeding, less number of directions used suggests that birds might be moving towards the directions having high probability of food availability. It is likely that avian dispersal in space and time is dependent on the food availability however, further studies are required to be carried out.     

Astressin-amide and astressin-acid are structurally different in dimethylsulfoxide

The C-terminally amidated CRF antagonist astressin binds to CRF-R1 or CRF-R2 receptors with low nanomolar affinity while the corresponding astressin-acid has >100 times less affinity. To understand the role of the amide group in binding, the conformations of astressin-amide and astressin-acid were studied in DMSO using NMR techniques. The 3D NMR structures show that the backbones of both analogs prefer an alpha-helical conformation, with a small kink around Gln(26). However, astressin-amide has a well-defined helical structure from Leu(27) to Ile(41) and a conformation very similar to the bioactive conformation reported by our group (Grace et al., Proc Natl Acad Sci USA 2007, 104, 4858-4863). In contrast, astressin-acid has an irregular helical conformation from Arg(35) onward, including a rearrangement of the side chains in that region. This structural difference highlights the crucial role of the C-terminal amidation for stabilization of astressin's bioactive conformation.     

A new high performance liquid chromatographic method for quantification of atomoxetine in human plasma and its application for pharmacokinetic study

Atomoxetine is the first, non-stimulant alternative to other stimulant medications used for the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD). Reported methods for the determination of atomoxetine include expensive liquid chromatography tandem mass spectrometry (LCMS) and high performance liquid chromatography (HPLC) with liquid scintillation counting (LSC) detection. Till date, no method has been reported in literature to determine atomoxetine using HPLC with UV detection. In this paper, we describe a new HPLC method for the determination of atomoxetine using liquid-liquid extraction with tertiary butyl methyl ether and UV detector. This method was found to be linear over the concentration range of 0.05-3.0 microg/ml. The limit of quantification was 0.05 microg/ml. Intra- and inter-day precision was <15% and accuracy was in the range of 95.67-108.80%. Stability studies showed that atomoxetine was stable in human plasma for short- and long-term period for sample preparation and analysis. This method was used for sample analysis in a pharmacokinetic study of atomoxetine (25mg) in five healthy adult female volunteers. The observed mean+/-S.D. pharmacokinetic parameters Cmax, Tmax and AUC(0-t) were 0.40+/-0.06 microg/ml, 3.40+/-0.42 h and 1.34+/-0.52 microg h/ml, respectively.     

Length–weight relationships of some fish from the Ganga River,India

Length–weight relationships (LWRs) were determined for seven riverine fish species from the river Ganga, India. Specimens were collected on a bi‐monthly basis from April 2017 to December 2018 using gill nets (mesh size 22–34 mm), cast nets (mesh size 16 mm) and bag nets (mesh size 14–22 mm). Total length was measured to the nearest 0.1 cm using a digital caliper and weight was recorded to the nearest 0.01 g on an electronic balance. From estimated length–weight relationships, the values for parameter “a” ranged from 0.004 (Bregmaceros mcclellandi and Setipinna tenuifilis) to 0.014 (Brachirus pan). Likewise, the values for the parameter “b” of the equation ranged from 2.958 (Bagarius bagarius) to 3.124 (Bregmaceros mcclellandi) and r² from 0.978 (Gonialosa manmina) to 0.996 (Brachirus pan).     

Light sensitivity of the photoperiodic response system in higher vertebrates: wavelength and intensity effects

Most species use daily light in one way or the other in regulation of their short and/or long term activities. Light is perceived by pigment(s) present in the retinal (RP) and/or extra-retinal photoreceptors (ERPs). ERPs may be located at various sites in the body but in non-mammalian vertebrates they are found predominantly in the pineal body and hypothalamic region of the brain, Light radiations directly penetrate brain tissues to reach and stimulate the hypothalamic (deep-brain) photoreceptors. How does light information finally reach to the clock is not fully understood in many vertebrate groups? In mammals, however, the light information from the retina to the clock (the hypothalamic suprachiasmatic nuclei, SCN) is relayed through the retino-hypothalamic tract (RHT) which originates from the retinal ganglion cells, and through the geniculo-hypothalamic tract (GHT) which originates from the photically responsive cells of a portion of the lateral geniculate nucleus (LGN), called the intergeniculate leaflet (IGL). A response to light (the photoperiodic response) is the result of the interpretation of light information by the photoperiodic system. Apart from the duration, the animals use the gradual shifts in the intensity and wavelength of daily light to regulate their photoperiodic clock system. The wavelengths to which photoreceptors are maximally sensitive or the wavelengths which have greater access to the photoreceptors can induce a maximal response. There can also be differential effects of wavelength and intensity of light on circadian process(es) involved in the entrainment and induction of the photoperiodic clock. This may have some adaptive implications. Entrainment to daily light-dark (LD) cycle may be achieved at dawn or dusk, depending whether the animal is day- or night-active, when there is relatively low intensity of light. By contrast, photoperiodic induction in many species occurs during long days of spring and summer when plenty of daylight at higher intensity is available later in the day.     

Regeneration of ethyl parathion antibodies for repeated use in immunosensor: a study on dissociation of antigens from antibodies

Reliable analysis using an immunosensor strongly depends on the specificity, activity, and sensitivity of the antibody. Immobilization of antibody on the solid matrix enables its repeated use, for which it is required to dissociate the antigens and antigen-enzyme conjugate from the immobilized antibody matrix after each use and while doing so, a maximum retention of activity and specificity are crucial requirements. In the present investigation, on the development of an immunosensor for the organophosphorus pesticide ethyl parathion (EP) using EP antibodies, different dissociating agents such as organic solvents, detergents and acidic buffers, that is, dimethyl sulphoxide (DMSO), Tween-20, cetyl trimethylammonium bromide (CTAB), methanol, chloroform, guanidium chloride (GdmCl), glycine-HCl (Gly-HCl) buffer in the pH range of 1.5-3.0, pierce buffer and combination of DMSO and methanol in phosphate buffer and Gly-HCl buffer and salts like NaCl and MgCl2 were used. Generally about 50-60% dissociation was obtained with some degree of denaturation of the antibody immobilized on the sepharose matrix. However, 1% DMSO in combination with 0.2 M Gly-HCl buffer at a pH of 2.3 showed 97% dissociation and the immobilized antibody retained sufficient activity to carry out 14 reproducible assays for EP.     

Reappraisal of the regulation of lactococcal L-lactate dehydrogenase

Lactococcal lactate dehydrogenases (LDHs) are coregulated at the substrate level by at least two mechanisms: the fructose-1,6-biphosphate/phosphate ratio and the NADH/NAD ratio. Among the Lactococcus lactis species, there are strains that are predominantly regulated by the first mechanism (e.g., strain 65.1) or by the second mechanism (e.g., strain NCDO 2118). A more complete model of the kinetics of the regulation of lactococcal LDH is discussed.     

Inorganic salts influence IAA ionization and adventitious rhizogenesis in Pongamia pinnata

The basal cut end of coppice shoot cuttings of Pongamia pinnata was treated for 24 h with 0 (water treated control) or 5.0 mmol/L of KMnO4, KCI, and KH2PO4 or 2.5 mmol/L of K2HPO4 and K2SO4. Inorganic salts of P, S, Cl and Mn significantly influenced IAA ionization and adventitious rhizogenesis. P and S salts had lower IAA ionization potential, but more pronounced effect on adventitious rhizogenesis than Cl and Mn salts. The linear regression analysis also established negative correlations between salt induced IAA ionization with various characteristics of adventitious rhizogenesis such as sprouting (r = -0.83, p < 0.05), rooting (r = -0.82, p < 0.05), root number (r = -0.95, p < 0.01), and root length (r = -0.80, p < 0.1). The implication of IAA ionization in adventitious rhizogenesis has been discussed and the possible role of inorganic salts therein suggested.