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991.
Drosophila larval hematopoiesis occurs in a specialized multi-lobed organ called the lymph gland. Extensive characterization of the organ has provided mechanistic insights into events related to developmental hematopoiesis. Spanning from the thoracic to the abdominal segment of the larvae, this organ comprises a pair of primary, secondary, and tertiary lobes. Much of our understanding arises from the studies on the primary lobe, while the secondary and tertiary lobes have remained mostly unexplored. Previous studies have inferred that these lobes are composed of progenitors that differentiate during pupation; however, the mechanistic basis of this extended progenitor state remains unclear. This study shows that posterior lobe progenitors are maintained by a local signaling center defined by Ubx and Collier in the tertiary lobe. This Ubx zone in the tertiary lobe shares several markers with the niche of the primary lobe. Ubx domain regulates the homeostasis of the posterior lobe progenitors in normal development and an immune-challenged scenario. Our study establishes the lymph gland as a model to tease out how the progenitors interface with the dual niches within an organ during development and disorders. 相似文献
992.
Photoluminescence (PL) and thermoluminescence (TL) properties of rare earth (RE) ion (RE = Dy3+, Sm3+, Ce3+, Tb3+) activated microcrystalline BaMgP2O7 phosphors are presented in this work. Non‐doped and doped samples of BaMgP2O7 were prepared using a solid state diffusion method and characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), PL and TL. The XRD measurement confirmed the phase purity of the BaMgP2O7 host matrix. The average particle size was found through SEM measurement to be around 2 μm. All activators using the PL technique displayed characteristic excitation and emission spectra that corresponded to their typical f → f and f → d transitions respectively. Thermoluminescence measurements showed that BaMgP2O7:RE (RE = Dy3+, Sm3+, Tb3+, Ce3+) and co‐doped BaMgP2O7:Ce3+,Tb3+ phosphors have also TL behaviour. 相似文献
993.
Charan Singh L. V. Seshu Kumar Koduri Tara Datt Bhatt Sarbjit Singh Jhamb Vijay Mishra Manjinder Singh Gill Sarasija Suresh 《AAPS PharmSciTech》2017,18(1):138-146
The objective of this study comprises of developing novel co-spray dried rifampicin phospholipid lipospheres (SDRPL) to investigate its influence on rifampicin solubility and oral bioavailability. Solid-state techniques were employed to characterize the liposphere formulation. SDRPL solubility was determined in distilled water. BACTEC 460TB System was employed to evaluate SDRPL antimycobacterial activity. The oral bioavailability of the lipospheres was evaluated in Sprague Dawley rats. Lipospheres exhibited amorphous, smooth spherical morphology with a significant increase (p?<?0.001) in solubility of SDRPL (2:1), 350.9?±?23 versus 105.1?±?12 μg/ml and SDRPL (1:1) 306.4?±?20 versus 105.1?±?12 μg/ml in comparison to rifampicin (RMP). SDRPL exhibited enhanced activity against Mycobacterium tuberculosis, H37Rv strain, with over twofolds less minimum inhibitory concentration (MIC) than the free drug. Lipospheres exhibited higher peak plasma concentration (109.92?±?25 versus 54.31?±?18 μg/ml), faster T max (two versus four hours), and enhanced area under the curve (AUC0–∞) (406.92?±?18 versus 147.72?±?15 μg h/L) in comparison to pure RMP. Thus, SDRPL represents a promising carrier system exhibiting enhanced antimycobacterial activity and oral bioavailability of rifampicin. 相似文献
994.
Length–weight relationships of five fish species from Carangidae family in waters of the northern Persian Gulf,Iran
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M. Parsa B. Rahnama M. Mahmoudi Khoshdarehgi 《Zeitschrift fur angewandte Ichthyologie》2017,33(5):1055-1057
This research describes and presents some biological aspects of five fish species from carangidae family including: Alepes djedaba, Ulua mentalis, Alectis indica, Carangoides coeruleopinnatus, and Carangoides bajad in the Iranian waters of the northern Persian Gulf (Hormozgan Province, Iran). Samples were collected from April to September 2016. The fishing gears were gill nets (80, 100, 120 and 145 mm stretched mesh size), bottom and midwater trawls (30, 40 and 75 mm stretched mesh size in cod‐end) of local and commercial fishery. The b values of length–weight relationships ranged from 2.512 (95% CL = 0.054) for U. mentalis to 2.953 (95% CL = 0.155) for C. coeruleopinnatus and the correlation coefficient values (r2) were high for all species. 相似文献
995.
Mahendra B. Bhalerao Sambhaji T. Dhumal Amarsinh R. Deshmukh Laxman U. Nawale Vijay Khedkar Dhiman Sarkar Ramrao A. Mane 《Bioorganic & medicinal chemistry letters》2017,27(2):288-294
New bithiazolyl hydrazones (6a–l) have been first time synthesized by carrying novel one pot cyclocondensation of 5-acyl thiazoles (1a–b), thiosemicarbazide (2) and substituted phenacyl chlorides (4a–f) in freshly prepared ionic liquid, diisopropyl ethyl ammonium acetate (DIPEAc) at room temperature. The newly synthesized compounds have been evaluated for their antitubercular activity and the compounds 3b, 6a, 6b, 6d, 6e, 6f, 6g, and 6l have displayed noticeable antitubercular activity compared to Rifampicin with tolerable cytotoxicity. All these compounds were also screened for their antibacterial activity and found that, compounds 6j and 6k have exhibited a very good antibacterial activity. Molecular docking study has shown better harmony with the evaluation trend shown by these compounds under in vitro antitubercular screening. 相似文献
996.
Neha Sami Vijay Kumar Asimul Islam Sher Ali Faizan Ahmad Imtaiyaz Hassan 《Molecular neurobiology》2017,54(7):5085-5106
Protein kinases are one of the largest families of evolutionarily related proteins and the third most common protein class of human genome. All the protein kinases share the same structural organization. They are made up of an extracellular domain, transmembrane domain and an intra cellular kinase domain. Missense mutations in these kinases have been studied extensively and correlated with various neurological disorders. Individual mutations in the kinase domain affect the functions of protein. The enhanced or reduced expression of protein leads to hyperactivation or inactivation of the signalling pathways, resulting in neurodegeneration. Here, we present extensive analyses of missense mutations in the tyrosine kinase focussing on the neurodegenerative diseases encompassing structure function relationship. This is envisaged to enhance our understanding about the neurodegeneration and possible therapeutic measures. 相似文献
997.
Ashok?KumarEmail author B.?R.?Maurya R.?Raghuwanshi Vijay?Singh?MeenaEmail author M.?Tofazzal Islam 《Journal of Plant Growth Regulation》2017,36(3):608-617
The aim of this work was to evaluate the effects of co-inoculation with phosphate-solubilizing and nitrogen-fixing rhizobacteria on growth promotion, yield, and nutrient uptake by wheat. Out of twenty-five bacteria isolated from the rhizosphere soils of cereal, vegetable, and agro-forestry plants in eastern Uttar Pradesh, three superior most plant growth-promoting (PGP) isolates were characterized as Serratia marcescens, Microbacterium arborescens, and Enterobacter sp. based on their biochemical and 16S rDNA gene sequencing data and selected them for evaluating their PGP effects on growth and yield of wheat. Among them, Enterobacter sp. and M. arborescens fixed significantly higher amounts (9.32?±?0.57 and 8.89?±?0.58 mg Ng?1 carbon oxidized, respectively) of atmospheric nitrogen and produced higher amounts (27.06?±?1.70 and 26.82?±?1.63 TP 100 µg mL?1, respectively) of IAA in vitro compared to S. marcescens (8.32?±?0.39 mg Ng?1 carbon oxidized and 21.29?±?0.99 TP 100 µg mL?1). Although both M. arborescens and S. marcescens solubilized remarkable amounts of phosphate from tricalcium phosphate likely through production of organic acids, however, Enterobacter sp. was inactive. The effects of these three rhizobacteria were evaluated on wheat in alluvial soils of the Indo-Gangetic Plain by inoculation of plants with bacterial isolates either alone or in combinations in both pot and field conditions for two successive years. Rhizobacterial inoculation either alone or in consortium of varying combinations significantly (P?≤?0.05) increased growth and yield of wheat compared to mock inoculated controls. A consortium of two or three rhizobacterial isolates also significantly increased plant height, straw yield, grain yield, and test weight of wheat in both pot and field trials compared to single application of any of these isolates. Among the rhizobacterial treatment, co-inoculation of three rhizobacteria (Enterobacter, M. arborescens and S. marcescens) performed best in promotion of growth, yield, and nutrient (N, P, Cu, Zn, Mn, and Fe) uptake by wheat. Taken together, our results suggest that co-inoculation of Enterobacter with S. marcescens and M. arborescens could be used for preparation of an effective formulation of PGP consortium for eco-friendly and sustainable production of wheat. 相似文献
998.
Richard A. Hartz Vivekananda M. Vrudhula Vijay T. Ahuja James E. Grace Nicholas J. Lodge Joanne J. Bronson John E. Macor 《Bioorganic & medicinal chemistry letters》2017,27(6):1360-1363
A series of phosphate and ester-based prodrugs of anilinopyrazinone 1 (BMS-665053) containing either a methylene or an (acyloxy)alkoxy linker was prepared and evaluated in rat pharmacokinetic studies with the goal of improving the oral bioavailability of the parent (1). The prodrugs, in general, had improved aqueous solubility and oral bioavailability compared to 1. Prodrug 12, which contains an (acyloxy)alkoxy linker, showed the greatest improvement in the oral bioavailability relative to the parent (1), with a seven-fold increase (from 5% to 36%) in rat pharmacokinetic studies. 相似文献
999.
A novel support has been utilized for immobilization of lipase, which was prepared by amination of silica with ethanolamine followed by cross linking with glutaraldehyde. Lipases from Rhizopus oryzae 3562 and Enterobacter aerogenes were immobilized on activated silica gel, where they retained 60 and 50% of respective original activity. The thermal stability of the immobilized lipases was significantly improved in comparison to the free forms while the pH stability remained unchanged. E. aerogenes and R. oryzae 3562 lipases retained 75 and 97% of respective initial activity on incubation at 90 degrees C, whereas both the free forms became inactive at this temperature. The conversion yield of isoamyl acetate was found to be higher with the immobilized fungal (90 vs. 21%) and bacterial lipases (64 vs. 18%) than the respective free forms. Immobilized R. oryzae 3562 lipases retained 50% activity for isoamyl acetate synthesis up to ten cycles whereas it was eight cycles for E. aerogenes. 相似文献
1000.
The avian influenza is an important infectious disease of birds. The genome of influenza A virus was segmented, single-stranded, negative-sense RNA molecules, which encodes many proteins. The significant surface proteins are hemagglutinin and neuraminidase for the pathogenicity of birds to humans. The prediction of epitopes in protein provides a suitable primary immunodiagnostic antigen for the detection of the influenza A virus H5N1. It was further used in the development and approval of epitopes, which were used as antigens, and the peptides can be used for vaccines in the potential control of an emerging pandemic of this pathogen. The conserved epitopes may be useful for the diagnosis of animals infected with the influenza virus. These might be helpful to prevent the spreading of influenza in animal to animal and also in the prevention and monitoring of its spread in the newer region. The epitopes provide the support for serodiagnosis or as a protective immunogen in novel vaccines. In this study, the preliminary data from the in silico analysis of hemagglutinin and neuraminidase was done to find potential T-cell epitopes. The determined peptides were beneficial for vaccine development, as they can reduce time by minimizing the number of required tests to find the possible selected epitopes, which target for vaccine development. T-cell recognition of the peptide-major histocompatible complex (MHC) is a prerequisite for cellular immunity. This work examines existing computational strategies for the study of peptide-MHC interactions. We have also provided guidelines for predicting antigenic peptides based on the availability of existing experimental data. 相似文献