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排序方式: 共有396条查询结果,搜索用时 281 毫秒
261.
262.
Sukhmal Chand M. Yaseen Rajkumari D. D. Patra 《International journal of phytoremediation》2015,17(12):1171-1176
A field experiment was conducted to evaluate the effective utilization of tannery sludge for cultivation of clarysage (Salvia sclarea) at CIMAP research farm, Lucknow, India during the year 2012–2013. Six doses (0, 20, 40, 60, 80, 100 tha?1) of processed tannery sludge were tested in randomised block design with four replications. Results revealed that maximum shoot, root, dry matter and oil yield were obtained with application of 80 tha?1of tannery sludge and these were 94, 113 and 61% higher respectively, over control. Accumulation of heavy metals (Cr, Ni, Fe, Pb) were relatively high in shoot portion of the plant than root. Among heavy metals, magnitude of chromium accumulation was higher than nickel, iron and lead in shoot as well as in root. Linalool, linalyl acetate and sclareol content in oil increased by 13,8 and 27% respectively over control, with tannery sludge application at 80 tha?1. Heavy metals such as chromium, cadmium and lead content reduced in postharvest soil when compared to initial status. Results indicated that clarysage (Salvia sclarea) can be grown in soil amended with 80 tha?1sludge and this can be a suitable accumulator of heavy metals for phytoremediation of metal polluted soils. 相似文献
263.
Patra Prasanta Ghosh Pratik Patra Bidhan Chandra Bhattacharya Manojit 《International journal of peptide research and therapeutics》2020,26(4):1687-1697
International Journal of Peptide Research and Therapeutics - Several types of RNase protein has been identified and characterized from different group of organism using advanced biocomputational... 相似文献
264.
Trypanothione reductase (TryR) is a validated drug target against Leishmaniasis. Using integrated computational and experimental approaches, the authors report doxorubicin and mitomycin C, known antitumor agents, as novel inhibitors of TryR of leishmania parasite. Interestingly, these compounds also act as subversive substrates and subvert the physiological function of enzyme by converting it from an anti-oxidant to a pro-oxidant. Possible mechanism of subversive substrate is discussed. Both doxorubicin and mitomycin C show significant effect on redox homeostasis of the parasite and high-leishmanicidal activity. The toxicity studies as well as available toxicity data in literature indicate these compounds to have acceptable toxicity in limited dose. 相似文献
265.
Dietary phytochemicals as rumen modifiers: a review of the effects on microbial populations 总被引:3,自引:0,他引:3
In the recent years, the exploration of bioactive phytochemicals as natural feed additives has been of great interest among
nutritionists and rumen microbiologists to modify the rumen fermentation favorably such as defaunation, inhibition of methanogenesis,
improvement in protein metabolism, and increasing conjugated linoleic acid content in ruminant derived foods. Many phytochemicals
such as saponins, essential oils, tannins and flavonoids from a wide range of plants have been identified, which have potential
values for rumen manipulation and enhancing animal productivity as alternatives to chemical feed additives. However, their
effectiveness in ruminant production has not been proved to be consistent and conclusive. This review discusses the effects
of phytochemicals such as saponins, tannins and essential oils on the rumen microbial populations, i.e., bacteria, protozoa,
fungi and archaea with highlighting molecular diversity of microbial community in the rumen. There are contrasting reports
of the effects of these phytoadditives on the rumen fermentation and rumen microbes probably depending upon the interactions
among the chemical structures and levels of phytochemicals used, nutrient composition of diets and microbial components in
the rumen. The study of chemical structure–activity relationships is required to exploit the phytochemicals for obtaining
target responses without adversely affecting beneficial microbial populations. A greater understanding of the modulatory effects
of phytochemicals on the rumen microbial populations together with fermentation will allow a better management of the rumen
ecosystem and a practical application of this feed additive technology in livestock production. 相似文献
266.
267.
Prashanth T. Bhaskar Veronique Nogueira Krushna C. Patra Sang-Min Jeon Youngkyu Park R. Brooks Robey Nissim Hay 《Molecular and cellular biology》2009,29(18):5136-5147
The current concept is that Tsc-deficient cells are sensitized to apoptosis due to the inhibition of Akt activity by the negative feedback mechanism induced by the hyperactive mTORC1. Unexpectedly, however, we found that Tsc1/2-deficient cells exhibit increased resistance to serum deprivation-induced apoptosis. mTORC1 hyperactivity contributes to the apoptotic resistance of serum-deprived Tsc1/2-deficient cells in part by increasing the growth factor-independent expression of hexokinase II (HKII) and GLUT1. mTORC1-mediated increase in hypoxia-inducible factor 1α (HIF1α) abundance, which occurs in the absence of serum in normoxic Tsc2-deficient cells, contributes to these changes. Increased HIF1α abundance in these cells is attributed to both an increased level and the sustained translation of HIF1α mRNA. Sustained glycogen synthase kinase 3β inhibition and Mcl-1 expression also contribute to the apoptotic resistance of Tsc2-deficient cells to serum deprivation. The inhibition of mTORC1 activity by either rapamycin or Raptor knockdown cannot resensitize these cells to serum deprivation-induced apoptosis because of elevated Akt activity that is an indirect consequence of mTORC1 inhibition. However, the increased HIF1α abundance and the maintenance of Mcl-1 protein expression in serum-deprived Tsc2−/− cells are dependent largely on the hyperactive eIF4E in these cells. Consistently, the reduction of eIF4E levels abrogates the resistance of Tsc2−/− cells to serum deprivation-induced apoptosis.Growth factors are obligatory for the survival of mammalian cells. The evolutionarily conserved kinase Akt has emerged as the predominant and indispensable mediator of the ability of growth factors to promote cell survival in mammalian cells (reviewed in reference 9). Akt promotes cell survival by multiple mechanisms, including key roles in regulating cellular energy metabolism. Akt maintains mitochondrial integrity and inhibits apoptosis at least in part through effects on mitochondrial hexokinases and their functionally coupled facilitated glucose transporters (reviewed in reference 18). One of the most crucial functions of Akt involves the activation of the mammalian target of rapamycin complex 1 (mTORC1), which integrates growth factor signaling with nutritional cues and synchronizes these upstream signals with the downstream stimulation of cell growth and proliferation (reviewed in reference 1). Akt activates mTORC1 in part by inhibiting the heterodimeric tuberous sclerosis complex (Tsc1/Tsc2). Tsc2 (or tuberin) functions as a GTPase-activating protein (GAP) to specifically inhibit the small GTPase Rheb, which activates mTORC1. The formation of a functional heterodimeric complex between Tsc2 and Tsc1 (or hamartin) is required for mTORC1 inhibition. As such, the disruption of the expression or function of either Tsc1 or Tsc2 is sufficient to activate mTORC1. Mammalian cells have evolved a negative feedback mechanism between mTORC1 and Akt to maintain an optimal balance between their activities. When Akt activates mTORC1, it initiates a negative feedback loop that serves to attenuate Akt activity. As such, mTORC1 serves as both an upstream and a downstream effector of Akt signaling. The loss of a functional Tsc1/Tsc2 complex disrupts this delicate balance, resulting in mTORC1 hyperactivity, which greatly reduces Akt activation (reviewed in reference 1). This is relevant to the heritable development of tuberous sclerosis in humans, which is caused by the mutational inactivation of either the TSC1 or TSC2 gene, leading to benign hamartoma formation and growth in a variety of organs (11).It is widely appreciated that low basal Akt activity renders Tsc1/2-deficient cells more sensitive to proapoptotic stimuli (4, 19). Unexpectedly, however, we found that both Tsc1 and Tsc2 null cells exhibit increased apoptotic resistance to growth factor withdrawal despite greatly reduced Akt activity relative to that of their wild-type counterparts. This implies that Tsc1/2 deficiency promotes or unmasks potent antiapoptotic mechanisms that reduce mammalian cell dependence upon growth factors and Akt for survival. Further investigation has uncovered a critical role for mTORC1 in promoting cell survival in the absence of growth factors.Trophic growth factors found in serum play a pivotal role in the cellular uptake and utilization of glucose, and serum withdrawal results in attenuated glucose metabolism. The maintenance of glucose utilization by the overexpression of the rate-limiting glycolytic enzyme hexokinase and its functionally coupled facilitative glucose transporters maintains cell survival in the absence of growth factors (reviewed in reference 18). We found that serum deprivation markedly increased both hexokinase II (HKII) and GLUT1 abundance in Tsc2-deficient cells, and the knockdown of HKII and GLUT1 increased the apoptotic susceptibility of these cells to serum deprivation. The elevated expression of HKII and GLUT1 is mediated by hypoxia-inducible factor 1α (HIF1α) protein, which is markedly induced by mTORC1 in serum-deprived Tsc2−/− cells.In addition to increased HKII and GLUT1 expression, Tsc2−/− cells display the sustained inhibition of glycogen synthase kinase 3 (GSK3) activity and stable Mcl-1 abundance following serum withdrawal, which also contribute to their apoptotic resistance under these conditions. Mcl-1 abundance, which normally declines following serum deprivation, is sustained in Tsc2−/− cells by the constitutive inhibition of GSK3 and the activation of eIF4E. 相似文献
268.
Ingrid Cezara Apetrei Gilda Eleonora Drăgănescu Ilinca Teodora Popescu Cătălin Carp-Cărare Eleonora Guguianu Traian Mihăescu Alina Ştefanache Carmen Creţu Xenia Patraş 《Aerobiologia》2009,25(3):159-166
The objective of this study was to investigate the airborne viable spore concentrations and identify the fungal species in
all indoor spaces from the lending library at the Technical University “Gheorghe Asachi” Iaşi, Romania. Samples were collected
using the settle plate method and swab samples from PC cooler fan grids as well as from the wall in it’s vicinity and from
paper/wood fragments. There were no air conditioning systems in the library rooms. The heating systems were standard with
an environmental temperature of 20°C in winter, except for the storage area of old/rare books stacks II, where the temperature
was below 15°C and the humidity was very high due to water infiltrations in the walls and poor maintenance. More than 296
fungal colonies from over 78 samples were identified, enumerated, and reported. Indoor airborne fungal spore deposition rates
were within the range of 419–1,677 CFU/m2, with the predominance of genera being Aspergillus spp., Penicillium spp., Cladosporium spp., Alternaria spp. and Chaetomium spp. Approximately ten fungal colonies could not be identified. The PC fans move particles from the low levels (floor) to
the air, and are thus responsible for maintaining a constant air velocity and contribute to fungal-spore aerosolization, transport,
deposition and resuspension. Book paper and wood furniture are known to be suitable substrates for cellulose degrading fungi. 相似文献
269.
270.
Dey B Bhunia SK Maity KK Patra S Mandal S Maiti S Maiti TK Sikdar SR Islam SS 《International journal of biological macromolecules》2012,50(3):591-597
Two different glucans (PS-I and PS-II) were isolated from the alkaline extract of the fruiting bodies of an edible mushroom, Pleurotus florida blue variant and the PS-I showed macrophage, splenocyte and thymocyte activations. On the basis of sugar analysis, methylation analysis, periodate oxidation, and NMR studies ((1)H, (13)C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC and HMBC), the structure of the repeating unit of these polysaccharides were established. 相似文献