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781.
Singh  Rajani  Misra  Amarendra Narayan  Sharma  Pallavi 《Protoplasma》2021,258(2):391-401
Protoplasma - Castor, a non-food, dedicated bioenergy crop, has immense potential to be used for phytoremediation/revegetation of heavy metal contaminated sites. In the previous study, we...  相似文献   
782.
BackgroundMesenchymal stem cells (MSCs) have paradoxically been reported to exert either pro- or anti-tumor effects in vitro. Hyperthermia, in combination with chemotherapy, has tumor-inhibiting effects; however, its role, together with MSCs, so far is not well understood. Furthermore, a lot of research is conducted using conventional 2-dimensional in vitro models that do not mimic the actual tumor microenvironment.AimIn light of this fact, an indirect method of co-culturing human amniotic membrane-derived MSCs (AMMSCs) with collagen-encapsulated human lung carcinoma cells (A549) was performed using a 3-dimensional (3D) tumor-on-chip device.MethodsThe conditioned medium of AMMSCs (AMMSC-CM) or heat-treated AMMSCs (heat-AMMSC-CM) was utilized to create indirect co-culture conditions. Tumor spheroid growth characterization, immunocytochemistry and cytotoxicity assays, and anti-cancer peptide (P1) screening were performed to determine the effects of the conditioned medium.ResultsThe A549 cells cultured inside the 3D microfluidic chip developed into multicellular tumor spheroids over five days of culture. The AMMSC-CM, contrary to previous reports claiming its tumor-inhibiting potential, led to significant proliferation of tumor spheroids. Heat-AMMSC-CM led to reductions in both spheroid diameter and cell proliferation. The medium containing the P1 peptide was found to be the least cytotoxic to tumor spheroids in co-culture compared with the monoculture and heat-co-culture groups.ConclusionsHyperthermia, in combination with the anticancer peptide, exhibited highest cytotoxic effects. This study highlights the growing importance of 3D microfluidic tumor models for testing stem-cell-based and other anti-cancer therapies.  相似文献   
783.
784.
Rapid and reliable physiological evaluation of stress is necessary for understanding the potential impacts of environmental changes on managed populations of threatened mammals. In situ populations of Australia’s iconic marsupial, the greater bilby (Macrotis lagotis), are nearing extinction due to the impacts of competition and predation by feral animals and unpredictable climatic events (summer heat waves). In this study, we focussed our aim to identify a non-invasive method to measure adrenal activity in the species and also to identify potential factors that should be considered when comparing physiological stress in semi-free ranging populations of the species. We validated an enzyme immunoassay (EIA) for detecting fecal cortisol metabolites (FCM) from fresh fecal pellets taken from bilbies within four captive sites and two semi-free ranging populations around Queensland and New South Wales, Australia. Our FCM EIA successfully detected the ‘raise and fall’ pattern of FCM levels within 3 days of exogenous adrenocorticotropic hormone (ACTH) challenge. Mean FCM levels differed significantly between the captive sites and between sexes. All male bilbies grouped outdoor in captivity expressed the highest mean FCM level in comparison to all captive males that were housed individually or as groups indoors. Also, semi-free ranging bilbies expressed higher mean FCM levels than the captive bilbies. Overall, our study successfully validated a non-invasive tool for monitoring physiological stress in the greater bilby. In the future, it will be worthwhile to consider factors such as housing conditions, sex and location when comparing the adrenal sensitivity to environmental changes, to help evaluate the success of management interventions (such as predator free enclosures) and support the survival of the species.  相似文献   
785.

Background

Low fruit and vegetable (FV) intake is a leading risk factor for chronic disease globally, but much of the world’s population does not consume the recommended servings of FV daily. It remains unknown whether global supply of FV is sufficient to meet current and growing population needs. We sought to determine whether supply of FV is sufficient to meet current and growing population needs, globally and in individual countries.

Methods and Findings

We used global data on agricultural production and population size to compare supply of FV in 2009 with population need, globally and in individual countries. We found that the global supply of FV falls, on average, 22% short of population need according to nutrition recommendations (supply:need ratio: 0.78 [Range: 0.05–2.01]). This ratio varies widely by country income level, with a median supply:need ratio of 0.42 and 1.02 in low-income and high-income countries, respectively. A sensitivity analysis accounting for need-side food wastage showed similar insufficiency, to a slightly greater extent (global supply:need ratio: 0.66, varying from 0.37 [low-income countries] to 0.77 [high-income countries]). Using agricultural production and population projections, we also estimated supply and need for FV for 2025 and 2050. Assuming medium fertility and projected growth in agricultural production, the global supply:need ratio for FV increases slightly to 0.81 by 2025 and to 0.88 by 2050, with similar patterns seen across country income levels. In a sensitivity analysis assuming no change from current levels of FV production, the global supply:need ratio for FV decreases to 0.66 by 2025 and to 0.57 by 2050.

Conclusion

The global nutrition and agricultural communities need to find innovative ways to increase FV production and consumption to meet population health needs, particularly in low-income countries.  相似文献   
786.
A total of 26,685 unutilized public domain expressed sequence tags (ESTs) of Arachis hypogaea L. were analyzed to give a total of 4442 EST-SSRs, in which 517 ESTs contained more than one simple sequence repeat (SSR). Of these EST-SSRs, 2542 were mononucleotide repeats (MNRs), 803 were dinucleotide repeats (DNRs), 1043 were trinucleotide repeats (TNRs), 40 were tetranucleotide repeats (TtNRs), six were pentanucleotide repeats (PNRs) and eight were hexanucleotide repeats (HNRs). Out of these 4442 EST-SSRs, only 1160 were found to be successful in non-redundant primer design; 1060 were simple SSRs, while the remaining 100 were compound forms. Among all the motifs, MNRs were abundant, followed by TNRs and DNRs. The AAG/CTT motif was the most abundant (~33 %) TNR, while AG/CT was the most abundant DNR. For redundancy and novelty, a stringent criterion deploying three different strategies was used and a total of 782 novel EST-SSRs were added to the public domain of peanut. These novel EST-SSR markers will be useful for qualitative and quantitative trait mapping, marker-assisted selection and genetic diversity studies in cultivated peanut as well as related Arachis species. A subset of 30 novel EST-SSRs was further randomly selected for validation and genotyping studies with eight well-known cultivars and 32 advanced breeding lines (ADBX lines, ADBY lines and ADBZ lines) from Odisha state, India. The number of polymorphic markers among accessions of A. hypogaea was low; however, a set of informative EST-SSR markers detected considerable levels of genetic variability in peanut cultivars and uncharacterized breeding lines collected from Odisha. The 30 newly developed EST-SSRs from Arachis spp. showed ~97 % amplification in Cicer arientinum and 93 % in pigeon pea. Thus, the EST-SSRs developed in this study will be a very useful asset for genetic analysis, comparative genome mapping, population genetic structure and phylogenetic inferences among wild and allied species of Arachis.  相似文献   
787.
We propose a highly sensitive side-polished birefringent photonic crystal fiber (PCF) sensor based on surface plasmon resonance (SPR). The polished surface of the proposed structure is coated with indium tin oxide (ITO) to excite plasmon and the analytes can be placed on the flat surface easily instead of filling the voids. The birefringent nature of the structure helps in coupling more fields to the ITO-dielectric interface. With the optimum thickness of 110 nm of ITO, the structure shows a maximum wavelength sensitivity of 17000 nm/RIU with a resolution of 5.8?×?10?6 RIU. Further this also showed an amplitude sensitivity of 74 RIU?1 along with a resolution of 1.35?×?10?5 RIU. Moreover, the effect of bending on this low loss structure is also analyzed.  相似文献   
788.
The coexistence of plant species in species‐rich tropical forests can be promoted by specialised enemies acting in a negatively density‐dependent manner. While survival of tropical tree seedlings is often negatively density‐dependent, the causes have rarely been identified. We tested whether insects and plant pathogens cause density‐dependent seedling recruitment and survival in five forest tree species in Belize, Central America. We manipulated densities of seeds or newly germinated seedlings in small (1 m2 or 0.25 m2) plots close to fruiting conspecific trees. Using a factorial design, we excluded enemies from subsets of the plots with fungicides and insecticides. Seed germination (for two species) and early seedling survival (for all species) were monitored at approximately weekly intervals for up to eight weeks, during the period when plants are likely to be most susceptible to natural enemies. In Terminalia amazonia, seed germination was negatively density‐dependent and the proportion of seeds germinating increased when insects were excluded. However, the magnitude of the insecticide effect was independent of density. The only significant density effect for survival of young seedlings was in Acacia polyphylla; counter to expectation, seedling survival was higher at high densities. In a few cases pesticide application had a significant effect on seedling survival, but in only one case (Terminalia amazonia) was a significant pesticide × density interaction detected. Our results caution against generalising from studies conducted on a single species at a single time and place and illustrate the challenges of experimentally testing for enemy‐mediated negative density‐dependence. Experimental outcomes are likely to depend on the spatial scale at which the principal enemies disperse and respond to plant density, and the timescales over which they act. Gathering information on these variables will improve our understanding of the natural histories of tropical forest species and help inform the design of future experiments.  相似文献   
789.
Fucoxanthin (Fx) and fucosterol (Fs) are characteristic lipid components of brown seaweeds that afford several health benefits to humans. This article describes the quantitative evaluation of lipids of 15 species of brown seaweeds with specific reference to Fx, Fs, and functional long‐chain omega‐6/omega‐3 polyunsaturated fatty acids (PUFAs). In addition, fatty‐acid composition of selected species was also accomplished in the study. Major omega‐3 PUFAs in the brown seaweeds analyzed were α‐linolenic acid (18:3n‐3), octadecatetraenoic acid (18:4n‐3), arachidonic acid (20:4n‐6), and eicosapentaenoic acid (20:5n‐3). Both Fx (mg · g?1 dry weight [dwt]) and Fs (mg · g?1 dwt) were determined to be relatively abundant in Sargassum horneri (Turner) C. Agardh (Fx, 3.7 ± 1.6; Fs, 13.4 ± 4.4) and Cystoseira hakodatensis (Yendo) Fensholt (Fx, 2.4 ± 0.9; Fs, 8.9 ± 2.0), as compared with other brown seaweed species. Studies related to seasonal variation in Fx, Fs, and total lipids of six brown algae [S. horneri, C. hakodatensis, Sargassum fusiforme (Harv.) Setch., Sargassum thunbergii (Mertens ex Roth) Kuntze, Analipus japonicus (Harv.) M. J. Wynne, and Melanosiphon intestinalis (D. A. Saunders) M. J. Wynne] indicated that these functional lipid components reached maximum during the period between January and March. The functional lipid components present in these seaweeds have the potential for application as nutraceuticals and novel functional ingredients after their recovery.  相似文献   
790.
Mahua oil (Madhumica indica) with an iodine value of 88 g/100 g, and containing 46% oleic acid and 12.74% linoleic acid, was epoxidised in situ with hydrogen peroxide as oxygen donor and glacial acetic acid as active oxygen carrier in presence of catalytic amount of an inorganic acid. Catalytic loading of two different acids, i.e., H2SO4 and HNO3 were studied, and H2SO4 was found to be more effective in terms of conversion to oxirane. The effects of various parameters, such as temperature, hydrogen peroxide-to-ethylenic unsaturation mole ratio, acetic acid-to-ethylenic unsaturation mole ratio, and stirring speed, on the epoxidation rate as well as on the oxirane ring stability and iodine value of the epoxidised mahua oil (EMO) were studied. The effects of these parameters on the conversion to the epoxidised oil were studied and the optimum conditions were established. The rate constant and activation energy for epoxidation of MO was found to be of the order of 10(-6) l mol(-1) s(-1) and 14.5 kcal mol(-1), respectively. Thermodynamic parameters such as enthalpy, entropy and free energy of activation were found to be of 13.8 kcal mol(-1), -51.1 cal mol(-1) K(-1) and 30.6 kcal mol(-1), respectively. Relative conversion data showed that it was possible to develop epoxides from locally available natural renewable resources such as mahua oil.  相似文献   
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