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121.
Candida infections and related mortality have become a challenge to global health. Nontoxic and natural bioactive compounds from plants are regarded as promising candidates to inhibit these multidrug resistant strains. In the present study, in vitro assays and in silico molecular docking approach was combined to evaluate the inhibitory effect of crude extracts from Allium ampeloprasum and its variety A. porrum on Candida pathogens. Phytochemical screening revealed the presence of phenolic acids and flavonoids in higher quantity. Spectral studies of the extracts support the presence of phenols, flavonoids and organosulfur compounds. Aqueous extract of A. ampeloprasum showed a total antioxidant capacity of 68 ± 1.7 mg AAE/ g and an IC50 value of 0.88 ± 2.1 mg/ml was obtained for DPPH radicals scavenging assay. C. albicans were highly susceptible (19.9 ± 1.1 mm) when treated with aqueous A. ampeloprasum extract. Minimum inhibitory concentrations were within the range of 19–40 μg/ml and the results were significant (p ≤ 0.05). In silico molecular docking studies demonstrated that bioactive phytocompounds of A. ampeloprasum and A. porrum efficiently interacted with the active site of Secreted aspartyl proteinase 2 enzyme that is responsible for the virulence of pathogenic yeasts. Rosmarinic acid and Myricetin exhibited low binding energies and higher number of hydrogen bond interactions with the protein target. Thus the study concludes that A. ampeloprasum and A. porrum that remain as underutilized vegetables in the Allium genus are potential anti-candida agents and their pharmacologically active compounds must be considered as competent candidates for drug discovery.  相似文献   
122.
The breast cancer 1 (BRCA1) protein is a tumor suppressor playing roles in DNA repair and cell cycle regulation. Studies of DNA repair functions of BRCA1 have focused on double-strand break (DSB) repair pathways and have recently included base excision repair (BER). However, the function of BRCA1 in BER is not well defined. Here, we examined a BRCA1 role in BER, first in relation to alkylating agent (MMS) treatment of cells and the BER enzyme DNA polymerase β (pol β). MMS treatment of BRCA1 negative human ovarian and chicken DT40 cells revealed hypersensitivity, and the combined gene deletion of BRCA1 and pol β in DT40 cells was consistent with these factors acting in the same repair pathway, possibly BER. Using cell extracts and purified proteins, BRCA1 and pol β were found to interact in immunoprecipitation assays, yet in vivo and in vitro assays for a BER role of BRCA1 were negative. An alternate approach with the human cells of immunofluorescence imaging and laser-induced DNA damage revealed negligible BRCA1 recruitment during the first 60 s after irradiation, the period typical of recruitment of pol β and other BER factors. Instead, 15 min after irradiation, BRCA1 recruitment was strong and there was γ-H2AX co-localization, consistent with DSBs and repair. The rapid recruitment of pol β was similar in BRCA1 positive and negative cells. However, a fraction of pol β initially recruited remained associated with damage sites much longer in BRCA1 positive than negative cells. Interestingly, pol β expression was required for BRCA1 recruitment, suggesting a partnership between these repair factors in DSB repair.  相似文献   
123.
The moulting interval of the euphausiid Thysanoessa inermisfrom the Barents Sea was found to be temperature dependent withinthe range of 1.5–8.0°C. Each moult accounted for a2.1% loss of dry body wt, equivalent to a 1.2–1.3% lossof body carbon or nitrogen. During 5 months of observation bothbody length and secondary sexual characters (thelycum and petasma)of specimens varied greatly, including positive and negativegrowth periods and progression and regression of maturity stages.Characteristics of eggs spawned by one female are described.  相似文献   
124.
Garlic (Allium sativum L.), is a predominant spice, which is used as an herbal medicine and flavoring agent, since ancient times. It has a rich source of various secondary metabolites such as flavonoids, terpenoids and alkaloids, which have various pharmacological properties. Garlic is used in the treatment of various ailments such as cancer, diabetes and cardiovascular diseases. The present study aims to explore the plausible mechanisms of the selected phytocompounds as potential inhibitors against the known drug targets of non-small-cell lung cancer (NSCLC). The phytocompounds of garlic were identified by gas chromatography-mass spectrometry (GC–MS) technique. Subsequently, the identified phytocompounds were subjected to molecular docking to predict the binding with the drug targets, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) and group IIa secretory phospholipase A2 (sPLA2-IIA). Molecular dynamics is used to predict the stability of the identified phytocompounds against NSCLC drug targets by refining the intermolecular interactions formed between them. Among the 12 phytocompounds of garlic, three compounds[1,4-dimethyl-7-(1-methylethyl)-2-azulenyl]phenylmethanone, 2,4-bis(1-phenylethyl)-phenol and 4,5–2 h-oxazole-5-one,4-[3,5-di-t-butyl-4-methoxyphenyl] methylene-2-phenyl were identified as potential inhibitors, which might be suitable for targeting the different clinical forms of EGFR and dual inhibition of the studied drug targets to combat NSCLC. The result of this study suggest that these identified phytocompounds from garlic would serve as promising leads for the development of lead molecules to design new multi-targeting drugs to address the different clinical forms of NSCLC.  相似文献   
125.
Life satisfaction refers to a somewhat stable cognitive assessment of one’s own life. Life satisfaction is an important component of subjective well being, the scientific term for happiness. The other component is affect: the balance between the presence of positive and negative emotions in daily life. While affect has been studied using social media datasets (particularly from Twitter), life satisfaction has received little to no attention. Here, we examine trends in posts about life satisfaction from a two-year sample of Twitter data. We apply a surveillance methodology to extract expressions of both satisfaction and dissatisfaction with life. A noteworthy result is that consistent with their definitions trends in life satisfaction posts are immune to external events (political, seasonal etc.) unlike affect trends reported by previous researchers. Comparing users we find differences between satisfied and dissatisfied users in several linguistic, psychosocial and other features. For example the latter post more tweets expressing anger, anxiety, depression, sadness and on death. We also study users who change their status over time from satisfied with life to dissatisfied or vice versa. Noteworthy is that the psychosocial tweet features of users who change from satisfied to dissatisfied are quite different from those who stay satisfied over time. Overall, the observations we make are consistent with intuition and consistent with observations in the social science research. This research contributes to the study of the subjective well being of individuals through social media.  相似文献   
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Krill plays a significant role in the Barents Sea ecosystem, providing energy transport between different trophic levels. The current paper presents the results of a long-term study (1980–2009) based on pelagic trawl catches from August to September. Our investigations show that the krill species were distributed widely in the Barents Sea and that the largest krill concentrations were restricted to the west-central and eastern parts of the Barents Sea. The current paper presents the relative biomass indices, and the estimates must be interpreted as minimum biomass. The mean annual krill biomass was estimated to be 22 million tonnes in wet weight, with the highest values being as much as 48 million tonnes. Capelin is the largest pelagic stock, and in some years, their biomass can amount to 4–7 million tonnes, which can impose high predation pressure on krill. When their biomass is high, capelin may consume close to 26 million tonnes annually. The predation from pelagic (herring and blue whiting) and bottom (cod and haddock) fish species was much lower, being 9 and 1 million tonnes, respectively. A negative relationship between krill biomass and capelin stock size above 74°N was observed during the study period. However, during the last decade, the krill biomass has increased despite heavy predation from capelin in some years. A positive significant linear relationship between the mean annual Kola temperature and the krill biomass seems to indicate that the recent warming conditions have favourable impacts on the krill populations in the Barents Sea.  相似文献   
129.
Heat shock protein 27 (HSP27) has been implicated in many intracellular signaling processes. Since the phosphorylation of HSP27 can modulate its activity, the ability to inhibit phosphorylation of HSP27 might have clinical relevance especially with regard to the treatment of fibrosis. We have developed a cell-permeant peptide inhibitor of MAPKAP Kinase 2 (MK2), an enzyme that phosphorylates HSP27, by combining a previously described peptide substrate of MK2 with a cell penetrating peptide. This novel MK2 inhibitor (MK2i) reduced HSP27 phosphorylation by MK2 in vitro. At 10 μM, MK2i inhibited TGF-β1-induced HSP27 phosphorylation in serum-starved human keloid fibroblasts. In addition, 10 μM MK2i decreased TGF-β1-induced expression of connective tissue growth factor and collagen type I within serum-starved keloid fibroblasts. Thus, MK2i represents a potential therapeutic for the treatment of fibrotic disorders.  相似文献   
130.
In this study, the genera, abundance, and activities of endophytic bacteria in field-grown white clover (Trifolium repens) and the fate of introduced antibiotic-tolerant bacteria in white clover tissues were investigated. Pseudomonas, Pantoea, and Corynebacterium were the most frequently isolated endophytic bacteria genera, whereas Xanthomonas, Microbacterium, and Cellulomonas occurred less frequently. The average bacterial populations in stolons and roots were approximately 100,000 colony-forming units (CFU) (g wet mass)-1. Of the 28 strains tested for activity, none were chitinolytic or able to inhibit the root pathogen Codinaea fertilis in vitro. However, Fusarium oxysporum and Cylindrocladium scoparium were inhibited by one and five strains, respectively. Four of seven strains tested depressed clover seedling growth. In pot experiments, colonization and recovery of spontaneous rifampicin-tolerant mutants (Rif+) of bacteria were studied in clover plants for periods up to 20 weeks. The strains used, sourced from white clover (endophytic and rhizoplane) and organic compost, had previously shown growth promotion potential of white clover seedlings by increasing plant mass and decreasing nematode numbers. In one experiment in this present study, five Rif+ strains were individually inoculated onto white clover seedlings, all five were re-isolated from shoots after 6 weeks and four strains were re-isolated after 20 weeks (numbers of Rif+ bacteria ranged from 51 to 200 CFU (g wet mass)-1). No Rif+ bacteria were isolated from root tissue at either time. In the second experiment, conducted with two strains of Rif+ bacteria, the population was highest in the shoots (range>500 CFU of Rif+ bacteria (g shoot fresh mass)-1) in weeks 2 and 3, declining to <200 CFU in week 5. Again, no Rif+ bacteria could be detected in roots. No Rif+ bacteria were recovered after 14 weeks for one of the strains. It appears that the main route of bacterial entry into seedlings was through stomata and that bacteria remained in the aerial parts of plants rather than migrating to the roots.  相似文献   
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