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Background: Curcuma caesia Roxb. (Zingiberaceae) is a rare, critically endangered medicinal plant of Northeast India. The rhizome of the plant is famous for its significant medicinal properties. Methods: Various concentrations of plant growth regulators in Murashige and Skoog (MS) medium were tried in the study using rhizome bud as explant for development of an efficient cost effective protocol for in vitro mass multiplication and microrhizome induction of Curcuma caesia. Result: Shoot multiplication and plant generation was achieved from freshly sprouted shoots of Curcuma caesia on Murashige and Skoog's medium supplemented with different phytohormones. The best response for shoot multiplication (23.80±0.51shoots/explant) was obtained within 8 weeks in MS medium supplemented with BAP (1.0 mgl -1) and 2,4-D (0.25 mgl -1). Microrhizomes were induced at the base of the in vitro derived shoots upon transferred to medium containing various combinations and concentrations of sucrose and BAP and grown under varying photoperiod. Half strength of MS basal medium containing BAP (1.0 mg/l) and 9% sucrose was found to be optimum for induction of large sized microrhizome within 45 days of incubation under 16 hrs of photoperiod. [ABSTRACT FROM AUTHOR]

The article discusses a study on the use of radio acoustic sounding system (RASS) with a 1280MHz lower atmospheric wind profile to preliminary observe temperature profiles at Gadanki, India. The study designs a suitable acoustic attachment to explore application of RASS technique. It reveals the presence of diurnal variation of virtual temperature Tv and the association of Tv perturbations with a precipitation event.

An in situ study was conducted to examine the mode of action of a 0.454% stannous fluoride (SnF 2 )-containing dentifrice in controlling the composition and properties of oral biofilm. Thirteen generally healthy individuals participated in the study. Each participant wore an intra-oral appliance over a 48-h period to measure differences in the resulting biofilm's architecture, mechanical properties, and bacterial composition after using two different toothpaste products. In addition, metatranscriptomics analysis of supragingival plaque was conducted to identify the gene pathways influenced. The thickness and volume of the microcolonies formed when brushing with the SnF 2 dentifrice were dramatically reduced compared to the control 0.76% sodium monofluorophosphate (MFP)-containing toothpaste. Similarly, the biophysical and nanomechanical properties measured by atomic force microscopy (AFM) demonstrated a significant reduction in biofilm adhesive properties. Metatranscriptomic analysis identified pathways associated with biofilm formation, cell adhesion, quorum sensing, and N-glycosylation that are significantly downregulated with SnF 2 . This study provides a clinically relevant snapshot of how the use of a stabilized, SnF 2 toothpaste formulation can change the spatial organization, nanomechanical, and gene expression properties of bacterial communities.

A fully conjugated cryptand-like bicyclic porphyrinoid ligand 4, incorporating three carbazole linkages and four dipyrrin moieties, was prepared via the acid-catalysed condensation of an extended 2,2'-bipyrrole analogue containing a central carbazole moiety and 3,4-diethyl-2,5-diformylpyrrole in 79% isolated yield. This new cryptand-like system acts as an effective ligand and allows for complexation of BF 2 (boron difluoride) subunits. Three BODIPY arrays, containing two, three, and four BF 2 subunits, namely 4·2BF 2 , 4·3BF 2 and 4·4BF 2 , could thus be isolated from the reaction of 4 with BF 3 ·Et 2 O in the presence of triethylamine at 110 °C, albeit in relatively low yield. As prepared, bicycle 4 is characterized by a rigid C 2 symmetric structure as inferred from VT NMR spectroscopic analyses. In contrast, the three BODIPY-like arrays produced as the result of BF 2 complexation are conformationally flexible and unsymmetric in nature as deduced from similar analyses. All four products, namely 4, 4·2BF 2 , 4·3BF 2 and 4·4BF 2 , were characterized by means of single crystal X-ray diffraction analyses. Tetramer 4·4BF 2 gives rise to a higher extinction coefficient (by 2.5 times) relative to the bis- and tris-BODIPY arrays 4·2BF 2 and 4·3BF 2 . This was taken as evidence for stronger excitonic coupling in the case of 4·4BF 2 . All three BODIPY-like arrays proved nearly non-fluorescent, as expected given their conformationally mobile nature. The efficiency of reactive oxygen species (ROS) generation was also determined for the new BODIPY arrays of this study., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The meso -unsubstituted expanded porphyrinoid 3, incorporating two carbazole moieties, acts as an effective ligand for Co(ii) and permits the isolation and X-ray diffraction-based characterization of a 6 : 3 metal-to-ligand metallocage complex that converts spontaneously to the constituent 2 : 1 metal-to-ligand metalloring species in chloroform solution. The discrete metalloring is formed directly when the Co(ii) complex is crystallized from supersaturated solutions, whereas crystallization from more dilute solutions favors the metallocage. Studies with two other test cations, Pd(ii) and Zn(ii), revealed exclusive formation of the monomeric metalloring complexes with no evidence of higher order species being formed. Structural, electrochemical and UV-vis-NIR absorption spectral studies provide support for the conclusion that the Pd(ii) complex is less distorted and more effectively conjugated than its Co(ii) and Zn(ii) congeners, an inference further supported by TD-DFT calculations. The findings reported here underscore how expanded porphyrins can support coordination modes, including bimetallic complexes and self-assembled cage structures, that are not necessarily easy to access using more traditional ligand systems., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Photoacoustic imaging (PAI) relies on the use of contrast agents with high molar absorptivity in the NIR-I/NIR-II region. Expanded porphyrins, synthetic analogues of natural tetrapyrrolic pigments ( e.g. heme and chlorophyll), constitute as potentially attractive platforms due to their NIR-II absorptivity and their ability to respond to stimuli. Here, we evaluate two expanded porphyrins, naphthorosarin ( 1 ) and octaphyrin ( 4 ), as stimuli responsive PA contrast agents for functional PAI. Both undergo proton-coupled electron transfer to produce species that absorb well in the NIR-II region. Octaphyrin ( 4 ) was successfully encapsulated into 1,2-distearoyl- sn -glycero-3-phosphoethanolamine-poly(ethylene glycol) (DSPE-PEG 2000 ) nanoparticles to afford OctaNPs . In combination with PAI, OctaNPs allowed changes in the acidic environment of the stomach to be visualized and cancerous versus healthy tissues to be discriminated., Competing Interests: J. F. A. and J. L. S. currently serve, respectively, as Vice President and a non-executive Director for OncoTEX, Inc. that provided partial support for this work., (This journal is © The Royal Society of Chemistry.)

Signals that activate the G protein Gαs and promote neuronal differentiation evoke Gαs internalization in rat pheochromocytoma (PC12) cells. These agents also significantly increase Gαs association with microtubules, resulting in an increase in microtubule dynamics because of the activation of tubulin GTPase by Gαs. To determine the function of Gαs/microtubule association in neuronal development, we used real-time trafficking of a GFP-Gαs fusion protein. GFP-Gαs concentrates at the distal end of the neurites in differentiated living PC12 cells as well as in cultured hippocampal neurons. Gαs translocates to specialized membrane compartments at tips of growing neurites. A dominant-negative Gα chimera that interferes with Gαs binding to tubulin and activation of tubulin GTPase attenuates neurite elongation and neurite number both in PC12 cells and primary hippocampal neurons. This effect is greatest on differentiation induced by activated Gαs. Together, these data suggest that activated Gαs translocates from the plasma membrane and, through interaction with tubulin/microtubules in the cytosol, is important for neurite formation, development, and outgrowth. Characterization of neuronal G protein dynamics and their contribution to microtubule dynamics is important for understanding the molecular mechanisms by which G protein-coupled receptor signaling orchestrates neuronal growth and differentiation., (© 2015 by The American Society for Biochemistry and Molecular Biology, Inc.)

The HIV glycoprotein gp120, a neurotoxic HIV glycoprotein that is overproduced and shed by HIV-infected macrophages, is associated with neurological complications of HIV such as distal sensory polyneuropathy, but interactions of gp120 in the peripheral nervous system remain to be characterized. Here, we demonstrate internalization of extracellular gp120 in a manner partially independent of binding to its coreceptor CXCR4 by F11 neuroblastoma cells and cultured dorsal root ganglion neurons. Immunocytochemical and pharmacological experiments indicate that gp120 does not undergo trafficking through the endolysosomal pathway. Instead, gp120 is mainly internalized through lipid rafts in a cholesterol-dependent manner, with a minor fraction being internalized by fluid phase pinocytosis. Experiments using compartmentalized microfluidic chambers further indicate that, after internalization, endocytosed gp120 selectively undergoes retrograde but not anterograde axonal transport from axons to neuronal cell bodies. Collectively, these studies illuminate mechanisms of gp120 internalization and axonal transport in peripheral nervous system neurons, providing a novel framework for mechanisms for gp120 neurotoxicity., (© The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

Three octaalkyl-substituted cyclo[4]naphthobipyrroles, studied in solution in the form of their sulfates, reveal absorption and magnetic circular dichroism (MCD) spectra very similar to those of the parent cyclo[8]pyrrole. A unique feature of these systems is a strong absorption in the near IR region. The analysis of MCD patterns based on a perimeter model reveals a hard-chromophore character of cyclo[4]naphthobipyrroles, i.e., ΔHOMO ≪ ΔLUMO. Comparison of Raman spectra obtained for crystalline samples and solutions, combined with the analysis of absorption and MCD spectra based on quantum chemical calculations reveals that cyclo[4]naphthobipyrroles exist in solutions as undissociated sulfates of the doubly protonated forms.

It is now evident that Galpha(s) traffics into cytosol following G protein-coupled receptor activation, and alpha subunits of some heterotrimeric G-proteins, including Galpha(s) bind to tubulin in vitro. Nevertheless, many features of G-protein-microtubule interaction and possible intracellular effects of G protein alpha subunits remain unclear. In this study, several biochemical approaches demonstrated that activated Galpha(s) directly bound to tubulin and cellular microtubules, and fluorescence microscopy showed that cholera toxin-activated Galpha(s) colocalized with microtubules. The activated, GTP-bound, Galpha(s) mimicked tubulin in serving as a GTPase activator for beta-tubulin. As a result, activated Galpha(s) made microtubules more dynamic, both in vitro and in cells, decreasing the pool of insoluble microtubules without changing total cellular tubulin content. The amount of acetylated tubulin (an indicator of microtubule stability) was reduced in the presence of Galpha(s) activated by mutation. Previous studies showed that cholera toxin and cAMP analogs may stimulate neurite outgrowth in PC12 cells. However, in this study, overexpression of a constitutively activated Galpha(s) or activation of Galpha(s) with cholera toxin in protein kinase A-deficient PC12 cells promoted neurite outgrowth in a cAMP-independent manner. Thus, it is suggested that activated Galpha(s) acts as an intracellular messenger to regulate directly microtubule dynamics and promote neurite outgrowth. These data serve to link G-protein signaling with modulation of the cytoskeleton and cell morphology.

The harvest management studies on an improved lemongrass strain Jor Lab L(2), were carried out at the farm of regional research Laboratory Jorhat during 1991-94. The crop was harvested at 60,70,80,90 and 100 days interval. Maximum oil yield was obtained when harvested at 90 days interval. The citral content ranged from 88 to 90% irrespective of crop age and harvesting schedule. Harvesting time has an important bearing on oil yield in Jor Lab L(2).