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1.
The conventional avian influenza vaccines rely on development of neutralizing antibodies against the HA and NA antigens. However, these antigens are highly variable, and hence there is a need for better vaccine candidates which would offer broader protection in animals. The M1 of avian influenza is another major structural protein that has conserved epitopes that are reported to induce CD8+ T cells and can contribute to protection against morbidity and mortality from influenza. Hence in an effort to study the immune response of rM1 either alone or in combination with rHA, the hemagglutinin (HA) and matrix protein (M1) of A/Hatay/2004/H5N1 strain of avian influenza were expressed in Pichia pastoris as his-tagged proteins and purified through Ni-NTA chromatography. The His-tag was removed using TEV protease cleavage site and the immunogenicity of purified rHA and rM1 either alone or in combination was determined in mice. One group of mice was immunized with 5 μg of purified rHA, the other group was immunized with rM1, and a third group of mice were immunized with 5 μg of rHA and rM1. All the animals were boosted twice, once on 28 days postimmunization (dpi) and the second on 42 dpi. The immune response was evaluated by enzyme-linked immunosorbent assay (ELISA) and hemagglutination inhibition (HI) assay. The group of mice immunized with rHA and rM1 together showed significantly higher immune response against rHA and rM1 than mice immunized with either HA or M1 antigens. The addition of rM1 with rHA resulted in increased HI titer in animals immunized with both the antigens. These results suggest that the HA and M1 expressed in P. pastoris can be utilized in combination for the development of faster and cost-effective vaccines for circulating and newer strains of avian influenza and would aid in combating the disease in a pandemic situation, in which production time matters greatly.  相似文献   
2.
Methanol, acetone and diethyl ether extracts of Alpinia galanga have been evaluated against pathogens viz. Bacillus subtilis MTCC 2391, Enterobacter aerogene, Enterobacter cloacae, Enterococcus faecalis, Escherichia coli MTCC 1563, Klebsiella pneumoniae, Pseudomonas aeruginosa MTCC 6642, Salmonella typhimurium, Staphylococcus aureus and Streptococcus epidermis using Agar well diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of all the extracts were determined using the macrodilution method. Methanol extracts have shown excellent activity towards all the pathogens with MIC and MBC values ranging from 0.04–1.28 mg/ml and 0.08–2.56 mg/ml, respectively. The GC–MS analysis of methanol extracts have yielded compounds like 5-hydroxymethyl furfural (59.9%), benzyl alcohol (57.6%), 1,8 cineole (15.65%), methylcinnamate (9.4%), 3-phenyl-2-butanone (8.5%) and 1,2 benzenedicarboxylic acid (8.9%), which could be responsible for its broad spectrum activity. So, A. galanga can be quite resourceful for the development of new generation drugs.  相似文献   
3.
Podophyllotoxin, a potent chemotherapeutic agent is obtained from Podophyllum hexandrum Royle. Embryos of P. hexandrum were transformed using different strains of Agrobacterium rhizogenes viz. A4, 15834, K599. Transformed nature of the calli was ascertained and the cultures were further maintained as individual clones. HPLG analysis of transformed cultures depicted a three-fold increase in podophyllotoxin content in comparison to controls.  相似文献   
4.
A series of 1‐acyl‐2‐pyrazoline derivatives derived from nonsteroidal anti‐inflammatory drugs was designed as potential anticancer agents. Synthesis of these compounds was carried out via the condensation reaction of chalcones and acid hydrazides under heating. The methodology did not require the use of any costly reagents or catalysts, and the acid hydrazide reactants were readily prepared from mefenamic acid or ibuprofen. A variety of 1‐acyl‐2‐pyrazolines was prepared in good to excellent yields. An N‐allylidene benzohydrazide intermediate was isolated during the reaction optimization study, the structure of which was confirmed unambiguously by X‐ray single crystal data. A range of N‐allylidene benzohydrazides were also prepared in good yields. Some of the compounds synthesized showed promising cytotoxic activities when tested against HCT‐15 human colon cancer cell line in vitro.  相似文献   
5.
Alpinia galanga is a rhizomatous herb rich in essential oils and various other significant phytoconstituents. Rapid direct regeneration was obtained from the rhizome explants (15.66 ± 0.57 shoots) on MS media supplemented with zeatin at a concentration of 2 mg/l. The callus cultures of A. galanga were initiated from the rhizome explants on MS media supplemented with 2 mg/l each of BAP, 2,4-D, and NAA. The callus was analyzed for the presence of a vital phytoconstituent--acetoxychavicol acetate (ACA) associated with various biological properties. ACA was detected in the young friable callus as well as the stationary phase callus. Moreover, the induction of morphogenetic response in callus resulted in higher accumulation of ACA. The phytohormone withdrawal from the propagation media and the subsequent transfer of callus to BAP (2 mg/l) containing MS media has resulted in multiple shoot induction. The regenerated (indirect) plants have shown 1.6-fold higher ACA content (1.253%) when compared to the control plant (0.783%). Micropropagation of such conventionally propagated plants is very essential to meet the commercial demand as well as to ensure easy storage and transportation of disease free stocks.  相似文献   
6.
Fast atom bombardment, combined with high-energy collision-induced tandem mass spectrometry, has been used to investigate gas-phase metal-ion interactions with captopril, enalaprilat and lisinopril, all angiotensin-converting enzyme inhibitors.Suggestions for the location of metal-binding sites are presented. For captopril, metal binding occurs most likely at both the sulphur and the nitrogen atom. For enalaprilat and lisinopril, binding preferably occurs at the amine nitrogen. Copyright 1999 John Wiley & Sons, Ltd.  相似文献   
7.
Electrospray mass spectrometry/mass spectrometry was used to investigate the gas‐phase properties of protonated expanded porphyrins, in order to correlate those with their structure and conformation. We have selected five expanded meso‐pentafluorophenyl porphyrins, respectively, a pair of oxidized/reduced fused pentaphyrins (22 and 24 π electrons), a pair of oxidized/reduced regular hexaphyrins (26 and 28 π electrons) and a regular doubly N‐fused hexaphyrin (28 π electrons). The gas‐phase behavior of the protonated species of oxidized and reduced expanded porphyrins is different. The oxidized species (aromatic Hückel systems) fragment more extensively, mainly by the loss of two HF molecules. The reduced species (Möbius aromatic or Möbius‐like aromatic systems) fragment less than their oxidized counterparts because of their increased flexibility. The protonated regular doubly fused hexaphyrin (non‐aromatic Hückel system) shows the least fragmentation even at higher collision energies. In general, cyclization through losses of HF molecules decreases from the aromatic Hückel systems to Möbius aromatic or Möbius‐like aromatic systems to non‐aromatic Hückel systems and is related to an increase in conformational distortion. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
8.
Raphanus sativus, a common cruciferous vegetable has been attributed to possess a number of pharmacological properties. Antioxidant and radical scavenging activity of R. sativus root extracted with solvents of varying polarity were evaluated using different model systems. Polyphenolic content was estimated to be in the range 13.18-63.54?mg?g?1 dry weight, with a considerable amount being obtained with polar solvents. High-performance liquid chromatography analysis indicated the presence of an array of polyphenolics. Catechin was found to be the most abundant phenolic compound in water extract and sinapic acid, the predominant phenolic compound in methanolic, ethyl acetate and hexane extracts. The methanolic extract showed significant ferric reducing ability, moderate metal chelating activity and strong radical scavenging activity. The methanolic extract could be successfully utilised as an ingredient in functional foods. However, water extract could be more pertinent to human nutrition as it contained a significant amount of catechin, which was comparable to traditional sources like green and black tea.  相似文献   
9.
10.
A highly enantioselective total synthesis of paecilocin A and 3-butyl-7-hydroxyphthalide is described. The key steps involved in this synthesis are enzymatic kinetic resolution and Alder–Rickert reaction.  相似文献   
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