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981.
More than 70 species of the Superfamily Paramphistomoidea, have been identified in ruminants in different parts of the world. Most are pathogenic, causing amphistomosis. Adult flukes within this family have a predilection for the forestomach (rumen) or bile duct of the liver, where they may cause epithelial damage. Identification of adult Paramphistomum, Calicophoron, Gastrothylax and Fischoederius at the species level based on morphology requires specialised expertise, whereas molecular genetic marker analysis is more precise and transferable. In the present study, we performed molecular characterisation of twenty seven adult flukes collected from the forestomachs of buffalo, cattle and goats in the Punjab province of Pakistan. PCR and sequencing of the ITS-2 rDNA region revealed a single haplotype in all cases. Phylogenetic comparison of P. epiclitum ITS2-rDNA sequences with those from other Paramphistomum, Calicophoron, Gastrothylax and Fischoederius species was performed to assess within and between species variation and validate the use of ITS-2 rDNA as a robust species-specific marker for P. epiclitum identification. This work provides a validated species-specific marker of P. epiclitum and the first report of this parasite species from Pakistan. The results of this study also have implications for the diagnosis and control of rumen flukes in the region and the need for accurate species identification to understand parasite distribution and population genetics.  相似文献   
982.
Abstract

The attraction of Allodorylaimus americaus towards excised (cut into two pieces) and non-excised (live) individuals of plant parasitic nematodes viz., Tylenchorhynchus mashhoodi, Hoplolaimus indicus, Helicotylenchus indicus, Hirschmanniella oryzae, Xiphinema americanum and Hemicriconemoides mangiferae used as prey were tested in a Petri dish. A. americanus responded positively and significantly to prey kairomones but showed variation in their individual behaviour. A. americanus was most attracted towards excised individuals of T. mashhoodi. The differential responses of A. americanus towards different prey were attributed to the inert behaviour of the predator, their preference for a particular species of prey, chemical composition, concentration, quality, quantity of prey attractant, formation of minimum perceptible attraction gradient of prey and minimum response threshold of predators. Different factors such as temperature, period of prey incubation, prey density, starvation of predators, agar concentration, and agar thickness governed the attraction responses of the predator. A. americanus responded maximally towards T. mashhoodi, when tested as 5-day starved predators in agar plates containing a 2 mm thick layer of 1% water-agar with 200 prey individuals previously incubated for 16 h at 30°C.  相似文献   
983.
In this study, chitosan was used as a flocculant to harvest freshwater microalgae Chlorella vulgaris. The recovery efficiency of C. vulgaris was tested at various chitosan concentrations. 120 mg/L of chitosan showed the highest efficiency (92 ± 0.4%) within 3 min. The maximum concentration factor of 10 was also achieved at this dose of chitosan. The harvesting efficiency was pH dependent. pH 6.0 showed the highest harvesting efficiency (99 ± 0.5%). Measurement of zeta-potential confirmed that the flocculation was induced by charge neutralization. This study showed that a biopolymer, chitosan, can be a promising flocculant due to its high efficacy, low dose requirements, and short settling time.  相似文献   
984.
A new series of asymmetric salicyl-, furanyl-, thienyl- and pyrrolyl-derived ONNO, NNNO, ONNS & NNNS donor antibacterial and antifungal Schiff-bases and their copper(II) and zinc(II) metal complexes have been synthesized and characterized. IR spectra indicated the ligands to act as quartdentate towards divalent metal ions via two azomethine-N, deprotonated-O of salicyl, furanyl-O, thienyl-S and/or pyrrolyl-N. The magnetic moments and electronic spectral data suggest octahedral geometry for Cu(II) and Zn(II) complexes. NMR spectral data of the ligands and their diamagnetic zinc(II) complexes well-define their proposed structures/geometries. Elemental analyses data of the ligands and metal complexes agree with their proposed structures/geometries. The synthesized ligands, along with their metal complexes were screened for their antibacterial activity against B. cereus, C. diphtheriae, E. coli, K. pneumoniae, P. mirabilis, P. aeruginosa, S. typhi, S. dysenteriae and S. aureus strains and for in-vitro antifungal activity against T. schoenleinii, C. glabrata, P. boydii, C. albicans, A. niger, M. canis and T. mentagrophytes. The results of these studies show the metal complexes to be more antibacterial/antifungal against one or more species as compared to the uncomplexed ligands. The brine shrimp bioassay was also carried out to study their in-vitro cytotoxic properties. Eight compounds, L4, (1), (7), (8), (11), (17), (19) and (23) displayed potent cytotoxic activity with LD50 = 1.445 × 10? 3, 1.021 × 10? 3, 7.478 × 10? 4, 8.566 × 10? 4, 1.028 × 10? 3, 9.943 × 10? 4, 8.730 × 10? 4 and 1.124 × 10? 3 M respectively, against Artemia salina.  相似文献   
985.
Novel cyclization of 4-(substituted-phenylsulfonamido)butanoic acids to their corresponding 1-[(substituted-phenyl)sulfonyl]pyrrolidin-2-ones was successfully achieved by using polyphosphate ester (PPE). The reaction time was considerably reduced with corresponding increase in the yields, when polyphosphate ester (PPE) was used in combination with 4-(N,N-dimethylamino)pyridine (DMAP). All the synthesized compounds were screened for their antimicrobial activity. Minimum Inhibitory Concentration (MIC) values of synthesized compounds were also determined, and were found to be in the range of 0.09–1.0 mg.  相似文献   
986.
Induced resistance is one of the important components of host plant resistance to insects. We studied the induced defensive responses in groundnut genotypes with different levels of resistance to the leaf defoliator Helicoverpa armigera and the sap-sucking insect Aphis craccivora to gain an understanding of the induced resistance to insects and its implications for pest management. The activity of the defensive enzymes (peroxidase, polyphenol oxidase, phenylalanine ammonia lyase, superoxide dismutase, ascorbate peroxidase, and catalase) and the amounts of total phenols, hydrogen peroxide, malondialdehyde, and proteins were recorded at 6 days after infestation. Induction of enzyme activities and the amounts of secondary metabolites were greater in the insect-resistant genotypes ICGV 86699, ICGV 86031, ICG 2271, and ICG 1697 infested with H. armigera and A. craccivora than in the susceptible check JL 24. The resistant genotypes suffered lower insect damage and resulted in lower Helicoverpa larval survival and weights than those larvae fed on the susceptible check JL 24. The number of aphids was significantly lower on insect-resistant genotypes than on the susceptible check JL 24. The results suggested that groundnut plants respond to infestation by H. armigera and A. craccivora in a similar way; however, the degree of the response differed across the genotypes and insects, and this defense response is attributed to various defensive enzymes and secondary metabolites.  相似文献   
987.
The aleurone layer of mature Arabidopsis thaliana seed plays important roles in seed germination and dormancy. However, the proteomic profile of this cell layer is unknown partly because it is difficult to separate this thin cell layer from the mature seeds. In this study, we have used a simple technique to separate the aleurone layer along with the seed coat following germination of seeds and determined for the first time the putative protein composition of this cell layer. By subjecting the total proteins extracted from the seed coat to 2D gel electrophoresis followed by liquid chromatography/tandem mass spectrometry, we identified four AGI loci, AT4G28520, AT5G44120, AT1G03880, and AT1G03890; all of which belong to the seed storage family of proteins. Because in Arabidopsis the diploid aleurone cells of the seed coat perform protein storage functions similar to that of triploid endosperm of other plant species, it is assumed that the above AGI loci are associated with the aleurone layer of the seed coat.  相似文献   
988.
Janus kinases (JAKs) belong to a crucial family of tyrosine kinases, implicated in the patho-physiology of multiple cancer types, and serve as striking therapeutic targets. To date, many potent, either ATP-competitive (PTK domain) or non-ATP-competitive JAK inhibitors have been identified. Among them, Tyrphostin AG-490 (2-cyano-3-(3,4-dihydroxyphenyl)-N-(phenylmethyl)-2-propenamide) is a well-known ATP-competitive inhibitor. However, its mode of action, details of interacting residues, and induced conformational changes in JAK-specific binding sites remain elusive. Here, through comparative structure analysis, molecular docking, and molecular dynamics simulation assays, we explored comparative binding patterns of AG-490 against JAK1, JAK2, and JAK3. Our results entail noteworthy observations about the binding affinity of AG-490 by illustrating distinctive amino acid residues lying at the conserved ATP-binding domains of JAK family members. By subsequent assessment of their structural homology and conserved structural folds, we highlight intriguing prospects to design more specific and potent inhibitors for selective targeting of JAK family members. Our comparative study provides a platform for the rational design of precise and potent inhibitor for selective targeting of JAK family members.  相似文献   
989.
The present study is a comprehensive effort for making spatially explicit vegetation type information, one of the basic inputs for species and habitat conservation, readily available to the decision makers, resource managers and nature conservationists. The present study was carried out to understand the vegetation composition and structure in Doda area of Western Himalayas, India. During the study, vegetation types were mapped using on-screen image interpretation technique of multispectral high resolution satellite data. A total of ten types of vegetation were delineated from the satellite data. Phytosociological data was collected for the forest, pasture and scrub classes using nested-quadrat approach to characterize the vegetation. A total of ten phytosociological parameters were analyzed. Pinaceae, Rosaceae and Asteraceae were the dominant plant families with most of the identified plant species having a very high medicinal value. Other important component of the study involved landscape modelling, using the Spatial Landscape Analysis Model for identifying disturbance regimes and biodiversity rich landscapes in the area. The model results indicate that most of the area contains a very rich biodiversity repository with only a few areas showing signs of disturbance where terrain is either complex or where the anthropogenic pressures on forest resources are apparent. The forest and nature conservation managers could use the conservation measures suggested on the basis of these research findings for developing biodiversity conservation strategies in the region.  相似文献   
990.
N-acetyl transferase (NAT) is responsible to catalyze the transfer of acetyl groups to arylamines from acetyl-CoA. Aralkylamine Nacetyl transferase (AANAT), which belongs to GCN5-related N-acetyl transferase member, is a globular 23-kDa cytosolic protein that forms a reversible regulatory complex with 14-3-3 proteins, AANAT regulates the daily cycle of melatonin biosynthesis in mammals, making it an attractive target for therapeutic control of abnormal melatonin production in mood and sleep disorders. There is no evidence available regarding α and β subunits, active site and their ASA value in Dopamine N-acetyl transferase. Therefore, we describe the development of Dopamine N-acetyl transferase model in Tribolium castaneum. We further document the predicted active sites in the structural model with solvent exposed ASA residues. During this study, the model was built by CPH program and validated through PROCHECK, Verify 3D, ERRAT and ProSA for reliability. The active sites were predicted in the model with further ASA analysis of active site residues. The discussed information thus provides insight to the predicted active site and ASA values of Dopamine N-acetyl transferase model in Tribolium castaneum.  相似文献   
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