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71.
The progression in lifespan has been associated with elevated intracellular reactive oxygen species (ROS) and oxidative stress level which contributes to development of age related disorders. The discovery of lifespan modulating phytomolecules may promote development of natural therapies against age related afflictions. Acacetin (5,7-dihydroxy-4-methoxyflavone), is a naturally occurring flavonoid known to possess therapeutic properties. To this end, the present study evaluates effect of acacetin (AC) on lifespan, stress and neurotoxicity for the first time by using well-established free living, multicellular Caenorhabditis elegans model system. The 25?μM dose of AC significantly prolonged the mean lifespan of worms by 27.31% in comparison to untreated control and other tested doses of AC. Additionally, AC enhanced stress resistance against oxidative and thermal stress in worms. Furthermore, AC attenuated age related intracellular ROS level, aggregation of age pigment lipofuscin and increased the mean survival in stress hypersensitive mev-1 mutant by 40.5%. AC supplementation also reduced the alpha synuclein aggregation in transgenic worm model of Parkinson’s disease. The enhanced stress resistance, lifespan and alleviation of age related pathology can be attributed to increment in stress modulatory enzymes like superoxide dismutase (SOD) and catalase (CAT) level. Altogether the results suggest AC exposure maintains stress level, health span and extends mean lifespan of C. elegans. The longevity promoting and neuromodulatory effects of AC are mediated by up regulation of the stress response genes sod-3 and gst-4. The present finding gives new insights of natural remedies and their future prospects in developing therapeutic interventions for managing age related diseases.  相似文献   
72.
Conventional leather processing involving depilation of animal hide by lime and sulphide treatment generates considerable amounts of chemical waste causing severe environmental pollution. Enzymatic depilation is an environmentally friendly process and has been considered to be a viable alternative to the chemical depilation process. We isolated an extracellular protease from Pseudomonas aeruginosa strain MCM B-327 with high depilation activity using buffalo hide as a substrate. This 33 kDa protease generated a peptide mass fingerprint and de novo sequence that matched perfectly with LasB (elastase), of Pseudomonas aeruginosa. In support of this data a lasB mutant of MCM B-327 strain lacked depilatory activity and failed to produce LasB. LasB heterologously over-produced and purified from Escherichia coli also exhibited high depilating activity. Moreover, reintroduction of the lasB gene to the P. aeruginosa lasB mutant via a knock-in strategy also successfully restored depilation activity thus confirming the role of LasB as the depilating enzyme.  相似文献   
73.
Endemic, obligate outcrossing plant species with narrow geographic distributions and disjunct populations are prone to loss of genetic diversity. Simultaneously, delineating clear species boundaries is important for targeted conservation efforts. The rare and endemic cactus, Sclerocactus brevihamatus subsp. tobuschii (SBT), has a parapatric relationship with Sclerocactus brevihamatus subsp. brevihamatus (SBB) but genetic distance between the two taxa is unknown. We: (1) developed taxon-specific polymorphic microsatellites, (2) assessed genetic diversity within and among nine populations of SBT, and within one population of SBB, and (3) estimated the genetic relationship between the two subspecies. Within-population genetic diversity of SBT was moderate to high (mean Ho?=?0.37; mean He?=?0.59). Indirect estimate of inbreeding corrected for null alleles (Fis-INEst) was low for SBT, ranging from 0.03 to 0.14 (mean Fis-INEst?=?0.07). Genetic differentiation among populations of SBT was low based on Fst (0.08) and AMOVA (ФPT?=?0.10). Lack of genetic and spatial correlation in SBT populations coupled with the presence of private alleles and bottleneck events in several populations suggests that reproductive isolation is occurring but that sufficient time may not have yet passed to manifest strong differentiation. Cluster analyses segregated the 10 populations into three distinct groups, and separated SBB genotypes clearly. Results suggest that while hybridization between the two subspecies may occur, SBT is clearly differentiated genetically from SBB to retain its current taxonomic status.  相似文献   
74.
Mycorrhizal association is a common characteristic in a majority of land plants, and the survival and distribution of a species can depend on the distribution of suitable fungi in its habitat. Orchidaceae is one of the most species‐rich angiosperm families, and all orchids are fully dependent on fungi for their seed germination and some also for subsequent growth and survival. Given this obligate dependence, at least in the early growth stages, elucidating the patterns of orchid–mycorrhizal relationships is critical to orchid biology, ecology and conservation. To assess whether rarity of an orchid is determined by its specificity towards its fungal hosts, we studied the spatial and temporal variability in the host fungi associated with one of the rarest North American terrestrial orchids, Piperia yadonii. The fungal internal transcribed spacer region was amplified and sequenced by sampling roots from eight populations of P. yadonii distributed across two habitats, Pinus radiata forest and maritime chaparral, in California. Across populations and sampling years, 26 operational taxonomic units representing three fungal families, the Ceratobasidiaceae, Sebacinaceae and Tulasnellaceae, were identified. Fungi belonging to the Sebacinaceae were documented in orchid roots only at P. radiata forest sites, while those from the Ceratobasidiaceae and Tulasnellaceae occurred in both habitats. Our results indicate that orchid rarity can be unrelated to the breadth of mycorrhizal associations. Our data also show that the dominance of various fungal families in mycorrhizal plants can be influenced by habitat preferences of mycorrhizal partners.  相似文献   
75.
Nine out of 22 microsatellite primers tested were successfully amplified on three samples of cod Gadus morhua L. (two contemporary and one archived otolith samples). All loci were polymorphic (5–23 alleles/locus). The average observed heterozygosity across loci and samples was 0.625, ranging from 0.294 to 0.895 at each locus. All loci were under Hardy–Weinberg equilibrium, except PGmo56 that showed significant excess of heterozygotes in all studied samples. The isolated loci were suitable for degraded DNA and therefore useful for conducting a long‐term temporal study with DNA obtained from archived otoliths of cod.  相似文献   
76.
Purple acid phosphatases belong to metallo-phosphatase family. Intracellular phosphatases are crucial for phosphorus (P) distribution in the cell and are highly induced in phosphorus-deprived conditions in the soil. Disparate PAP isoforms exist within discrete subcellular compartments in Setaria italica and their expression in P deprived conditions fosters phosphorus amelioration. We isolated the SiPAP18 gene and developed the homology SiPAP18 protein model based on the crystal structure of the Kidney bean PvPAP (PDB ID: 2QFP) as template (sequence similarity 42.7%) using Modeller 9.12 with adequate validation. Structure model analysis shows the significance of five conserved signatures with seven metal-paired amino acid residues during P-deprivation induced phosphorus amelioration.  相似文献   
77.

This essay investigates the phenomenon of global television in India and how Indian children, particularly those from the upper middle class, are being integrated into a global consumer cuitare. I suggest that in spite of the surface homogeneity of children's culture global capitalism mediates experiences of children differentially depending on class and location. It has led to greater class stratification in children's play and Indian children, unlike their American counterparts, are socialized to be producers rather than consumers.  相似文献   
78.
A number of stage-specific antigens have been characterized for vaccine development against Plasmodium falciparum malaria. This study presents a comprehensive analysis of the sequence polymorphism in Plasmodium falciparum apical membrane antigen-1 (PfAMA-1) in population samples from the eastern and western parts of India. This is the first study of its kind for the nearly full length PfAMA-1 gene from these regions in India. Our observations confirmed that sequence diversity of PfAMA-1 confines only to point mutations and shows 4-8% variation as compared to the prototypes. As opposed to the previous studies on PfAMA-1, our study revealed a greater degree of polymorphism in the Domain II region of PfAMA-1 protein, though signature for diversifying selection is seen throughout the gene. Our present investigation also indicates a very high degree of variation in the reported T- and B-cell epitopes of PfAMA-1. Few noteworthy and unique observations made in this study are the substitution of Cysteine residues responsible for the disulfide bond structure of the protein and the presence of premature termination after 595 amino acids in 3 of the 13 isolates under consideration. These crucial findings add new perspectives to the future of AMA-1 research and could have major implications in establishing AMA-1 as a vaccine candidate.  相似文献   
79.
80.
In certain rat strains, chronic estrogen administration can lead to pyometritis, an inflammation of the uterus accompanied by infection and the accumulation of intraluminal pus. In this article, we report that the Brown Norway (BN) rat is highly susceptible to pyometritis induced by 17β-estradiol (E2). The susceptibility of the BN rat to E2-induced pyometritis appears to segregate as a recessive trait in crosses to the resistant August × Copenhagen Irish (ACI) strain. In a (BN × ACI)F2 population, we find strong evidence for a major genetic determinant of susceptibility to E2-induced pyometritis on rat chromosome 5 (RNO5). Our data are most consistent with a model in which the BN allele of this locus, designated Eutr1 (Estrogen-induced uterine response 1), acts in an incompletely dominant manner to control E2-induced pyometritis. Furthermore, we have confirmed the contribution of Eutr1 to E2-induced uterine pyometritis using an RNO5 congenic rat strain. In addition to Eutr1, we obtained evidence suggestive of linkage for five additional loci on RNO2, 4, 11, 17, and X that control susceptibility to E2-induced pyometritis in the (BN × ACI)F2 population.  相似文献   
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