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991.
992.
Muhammad Bilal Maimoona Qindeel Leonardo Vieira Nunes Marco Thúlio Saviatto Duarte Luiz Fernando Romanholo Ferreira Renato Nery Soriano Hafiz M. N. Iqbal 《Marine drugs》2021,19(1)
Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease with a prevalence rate of up to 1% and is significantly considered a common worldwide public health concern. Commercially, several traditional formulations are available to treat RA to some extent. However, these synthetic compounds exert toxicity and considerable side effects even at lower therapeutic concentrations. Considering the above-mentioned critiques, research is underway around the world in finding and exploiting potential alternatives. For instance, marine-derived biologically active compounds have gained much interest and are thus being extensively utilized to confront the confines of in practice counterparts, which have become ineffective for 21st-century medical settings. The utilization of naturally available bioactive compounds and their derivatives can minimize these synthetic compounds’ problems to treat RA. Several marine-derived compounds exhibit anti-inflammatory and antioxidant properties and can be effectively used for therapeutic purposes against RA. The results of several studies ensured that the extraction of biologically active compounds from marine sources could provide a new and safe source for drug development against RA. Finally, current challenges, gaps, and future perspectives have been included in this review. 相似文献
993.
994.
Jessica F. Evanson Catherine Y. Alexander Fernando Sampedro Timothy Boyer André J Nault 《Journal Of Agricultural & Food Information》2013,14(3):220-236
The U.S. Food Safety Modernization Act, administered by the Food and Drug Administration (FDA), requires animal feed and pet food facilities to conduct a hazard analysis by identifying and evaluating potential hazards in animal food. This paper describes the creation of an information tool designed to help animal food facilities comply with this requirement. A thorough search of the scientific literature and FDA recall data identified the occurrence of hazards in animal food, assessed the severity of the hazards, and provided a scoring system useful for the identification and prioritization of specific animal food-hazard-species combinations. 相似文献
995.
Fernando Diánez Francisco Marín Francisco J. Gea María J. Navarro Maximino Piñeiro 《Compost science & utilization》2013,21(4):256-270
AbstractCompost tea has been used throughout the world to control diseases and promote the growth of plants. The microbial community is the main factor involved both in the antagonistic effect against relevant phytopathogens and as a stimulator of plant growth. The objective of this research is to determine the bacterial diversity present in four types of compost as well as some of the mechanisms that may be involved in the positive effects of compost tea on crops. Aerated (ACT) and non-aerated (NCT) compost teas were obtained from four different composts: spent mushroom substrate compost (SMC), grape marc compost (GMC), greenhouse horticultural crop residues compost (CRC), and vermicompost (CRV). 16S rDNA-based DGGE profiles were obtained for each compost tea and their respective bacterial communities were analyzed. Of the 100 clones obtained, those typical for being dominant for all profiles were chosen. In total, 20 different clones were sequenced. The results showed that the bacterial communities of most compost teas had high richness, diversity, and evenness values, with relative abundance of species belonging to Bacteroidetes and Proteobacteria. The NCTs obtained from all the composts, especially CRC and CRV, showed high levels of siderophore production, while teas from GMC manifested high and consistent cellulase activity. The ACTs from all the composts, especially SMC, had high protease activity. 相似文献
996.
A comparative study on the suitability of one compost and two vermicomposts, obtained from the same batch of tomato‐crop waste, as growth media for ornamental plant production was carried out. Each material was mixed with Sphagnum peat at 100 : 0, 75 : 25, 50 : 50, 25 : 75, and 0 : 100 (peat control) proportions by volume. Two ornamentals (Calendula officinalis, Viola cornuta) were sown and grown in the 13 substrates. Substrates were characterized physically and chemically. Seed germination, total leaf chlorophyll (SPAD units), plant growth, and plant nutrient concentrations were determined. The compost and the vermicomposts were markedly different from peat. Compost and the vermicomposts had greater bulk density and lower total porosity than peat. Compost had larger aeration and lower water‐holding capacity than vermicomposts and peat. Compost and vermicomposts were alkaline (pH = 8.8 on average) whilst peat was acidic (pH = 5.9). Electrical conductivity was low in peat (0.23 dS m–1) and vermicomposts (0.65 dS m–1), and high in compost (2.85 dS m–1) due to the high concentrations of K+ and SO$ _4^{2-} $ . Mixing compost and vermicomposts with peat produced substrates with intermediate characteristics. Physical properties were within adequate range for all mixes except for the compost ones. pH was within adequate range only in pure peat, and salinity was extremely high in the compost mixes. Compost was phytotoxic, as shown by the strong reduction of seed germination, chlorophyll content, and plant growth of both ornamentals. Vermicomposts did not affect seed germination but reduced plant growth, though much less than compost. Mixing these materials with peat improved germination and growth. The diluted materials (compost at the 25 : 75 and vermicomposts at the 50 : 50 and 25 : 75 proportions) produced good‐quality plants. 相似文献
997.
Hessels JW Ransom SM Stairs IH Freire PC Kaspi VM Camilo F 《Science (New York, N.Y.)》2006,311(5769):1901-1904
We have discovered a 716-hertz eclipsing binary radio pulsar in the globular cluster Terzan 5 using the Green Bank Telescope. It is the fastest spinning neutron star found to date, breaking the 24-year record held by the 642-hertz pulsar B1937+21. The difficulty in detecting this pulsar, because of its very low flux density and high eclipse fraction (approximately 40% of the orbit), suggests that even faster spinning neutron stars exist. If the pulsar has a mass less than twice the mass of the Sun, then its radius must be constrained by the spin rate to be <16 kilometers. The short period of this pulsar also constrains models that suggest that gravitational radiation, through an r-mode (Rossby wave) instability, limits the maximum spin frequency of neutron stars. 相似文献
998.
The conidial tolerance of Metarhizium anisopliae var.anisopliae isolate ARSEF 2575 to UV-B irradiation is greatly influenced by growth-environment alterations. In this review, we report high variability in conidial UV-B tolerance in response to altered culture conditions.Conidia produced on insect cadavers[Zophobas morio(Coleoptera) or Galleria mellonella(Lepidoptera)] had low tolerance to UV-B radiation; and conidia produced on potato dextrose agar supplemented with yeast extract (PDAY) had medium UV-B tolerance; whereas conidia produced on a minimal medium without any carbon source (MM), on MM with a non-preferred carbon source such as lactose (=MML), on PDAY plus 1 M NaCl or KCl, or PDBY with high alkalinity had the highest UV-B tolerances. All of the above conditions that induced high UV-B tolerance, however, also greatly reduced conidial production. Comparisons between stress tolerance and conidial production, particularly with conidia produced under osmotic and nutritive stress, point out that the benefits of producing very tolerant conidia have the enormous cost of low conidial production. Growth under visible light also greatly improved conidial UV-B tolerance, but light did not negatively influence conidial production. Therefore, culture on rich media under light is proposed as the most promising approach to producing conidia with improved UV-B tolerance for biological control of pest insects in agriculture. 相似文献
999.
Kifayat U. Khan Cleber F.M. Mansano Thiago M.T. Nascimento André Z. Boaratti Andressa T. Rodrigues Daniel M.A. Queiroz Rafael S. Romaneli Nilva K. Sakomura João B.K. Fernandes 《Journal of the World Aquaculture Society》2020,51(1):224-234
In the present study, juvenile (live body weight, 54.3 ± 8.2 g), preadult (live body weight, 822.5 ± 33.9 g), and adult (live body weight, 1,562.8 ± 41.8 g) pacu, Piaractus mesopotamicus, were used to estimate their dietary essential amino acid (EAA) requirements using the whole-body amino acid (AA) pattern. The results showed that whole-body moisture, crude protein, total lipid, and ash contents expressed on a wet weight basis (%) were significantly different among the studied growth phases. No significant differences were observed in the dietary EAA requirements estimated for the three growth phases of pacu. These dietary EAA requirements were found to be different than those previously estimated for the same fish through its muscle AA pattern. Based on whole-body EAA to total EAA ratios {A/E ratios; [(each EAA/total EAA) × 1,000]}, EAA requirements were estimated to be histidine (0.42%), arginine (1.36%), threonine (0.82%), valine (0.90%), methionine (0.45%), isoleucine (0.83%), leucine (1.29%), phenylalanine (0.74%), lysine (1.64%), and tryptophan (0.14%) for pacu. These estimated requirements may serve as a reference line in the formulation of practical and experimental diets until dose–response-based optimum EAA requirements are available for pacu. 相似文献
1000.
Froylan Sosa Salvador Romo Michael E. Kjelland Horacio Álvarez-Gallardo Sandra Pérez-Reynozo David Urbán-Duarte Jose Fernando De La Torre-Sánchez 《Reproduction in domestic animals》2020,55(11):1490-1500
The pterostilbene (PT) molecule is a phytoalexin with a reducing effect on reactive oxygen species (ROS) and with a capacity to block lipogenesis. However, the potential reducing effects of PT on equatorial lipid accumulation and ROS have not yet been elucidated for in vitro-derived bovine embryos. The present study evaluated the effects of concentrations of 3, 1, 0.33, 0.11 μM PT, and a vehicle group on the percentage of cleaved embryos, embryos with more than 6 cells, percentage of blastocyst on Day 7 and 8, percentage of transferable embryos on Day 7, the cell count and relative concentration of lipids. In the second experiment, the effects of 0.33 μM PT and a vehicle group within two different O2 environments (5% and 20%) were evaluated for ROS generation and the percentage of Day 8 blastocysts. In the first experiment, no significant differences were found between the treatments with PT and the vehicle group (p > .05) concerning the percentage of cleaved embryos and embryos with more than 6 cells. Lipid reduction was observed in the groups treated with PT versus the vehicle group (p < .05). The vehicle group showed a higher rate of blastocyst production on Days 7 and 8 (p < .05) and an increase in the percentage of transferable embryos on Day 7 compared to the PT treatment groups (p < .05). Cell counts were not significantly different between treatments with PT and the vehicle group (p > .05). In the second experiment, the O2 concentration did not significantly affect ROS generation (p > .05); however, the groups treated with PT (0.33 μM) had a reduction in ROS (p < .05). The O2 concentration also did not significantly affect the rate of blastocyst production on Day 8 (p = .7696). Future research should be conducted to ascertain whether the reduction of lipids could enhance the cryopreservation and post-thaw viability of PT-treated embryos. 相似文献