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排序方式: 共有250条查询结果,搜索用时 31 毫秒
91.
Gennaro Riccio Kevin A. Martinez Jesús Martín Fernando Reyes Isabella DAmbra Chiara Lauritano 《Marine drugs》2022,20(6)
Jellyfish are commonly considered a nuisance for their negative effects on human activities (e.g., fisheries, power plants and tourism) and human health. However, jellyfish provide several benefits to humans and are commonly eaten in eastern countries. Additionally, recent studies have suggested that jellyfish may become a source of high-value molecules. In this study, we tested the effects of the methanolic extracts and enriched fractions, obtained by solid-phase extraction fractionation, from the scyphomedusae Pelagia noctiluca, Rhizostoma pulmo, Cotylorhiza tuberculata and the cubomedusa Caryddea marsupialis on different human cancer cell lines in order to evaluate a potential antiproliferative activity. Our results indicated that fraction C from Caryddea marsupialis-(CM) and C. tuberculata oral arms (CTOA) were the most active to reduce cell viability in a dose-dependent manner. LC/MS based dereplication analyses highlighted that both bioactive fractions contained mainly fatty acids and derivatives, with CM additionally containing small peptides (0.7–0.8 kDa), which might contribute to its higher biological activity. The mechanism of action behind the most active fraction was investigated using PCR arrays. Results showed that the fraction C of CM can reduce the expression of genes involved in apoptosis inhibition in melanoma-treated cells, which makes jellyfish a potential new source of antiproliferative drugs to be exploited in the future. 相似文献
92.
Laparra JM Vélez D Barberá R Farré R Montoro R 《Journal of agricultural and food chemistry》2005,53(22):8829-8833
Arsenic is present in rice grain mainly as inorganic arsenic. Little is known about the effect of cooking on inorganic arsenic content in rice and its bioavailability. This study evaluated total arsenic and inorganic arsenic in rice cooked with arsenic-contaminated water, the bioaccessibility of As(III) and As(V) after simulated gastrointestinal digestion, and the extent of arsenic retention and transport by Caco-2 cells used as a model of intestinal epithelia. After cooking, inorganic arsenic contents increase significantly. After simulated gastrointestinal digestion, the bioaccessibility of inorganic arsenic reached 63-99%; As(V) was the main species found. In Caco-2 cells, arsenic retention, transport, and total uptake (retention + transport) varied between 0.6 and 6.4, 3.3 and 11.4, and 3.9 and 17.8%, respectively. These results show that in arsenic endemic areas with subsistence rice diets, the contribution of inorganic arsenic from cooked rice should be considered in assessments of arsenic health risk. 相似文献
93.
Perales S Barberá R Lagarda MJ Farré R 《Journal of agricultural and food chemistry》2006,54(13):4901-4906
Calcium solubility, dialysability, and transport and uptake (retention + transport) by Caco-2 cells as indicators of calcium bioavailability have been estimated in the in vitro gastrointestinal digests of milk and calcium fortified milk. A significant linear correlation (p < 0.05) was obtained between calcium uptake and the amount of soluble calcium added to the cells, and also between percentage calcium uptake and the calcium measured in the analyzed samples. The solubility, dialysis, transport, and uptake values are higher (p < 0.05) for calcium fortified milks than for nonfortified milks; that is, calcium fortification increases not only calcium content but also its bioavailability. An inhibitory effect of calcium from fortified milks upon iron absorption was found. The observed effect of calcium from fortified milks upon zinc bioavailability depends on the in vitro method used, zinc solubility and dialysis decrease in calcium fortified milks, and percentage zinc uptake remains unchanged. 相似文献
94.
E S Reyes K M Norris C Taylor D Potts 《Journal of the Association of Official Analytical Chemists》1988,71(1):16-19
A paired-ion liquid chromatographic (LC) technique coupled with fluorometric detection to determine riboflavin in various food matrices is described. Chromatograms of many foods showed 2 peaks of interest due to presence of riboflavin and flavin mononucleotide (FMN). Relatively high levels of FMN were found in raw beef, corned beef, chicken liver, and canned mushrooms. When riboflavin and FMN contents were summed, LC values were comparable to those obtained by the AOAC standard procedures. The LC technique was sensitive, rapid, and simple, yielding a mean standard deviation of 3.1% which was comparable to the AOAC fluorometric method (3.0%) and better than the AOAC microbiological assay (9.6%). Mean spike recoveries were 91.8% for LC compared to 90.5% and 89.6% for the AOAC fluorometric and microbiological methods, respectively. 相似文献
95.
96.
M. Hamon B. Dequeant A. Decambron E. Reyes‐Gomez M. Manassero 《The Journal of small animal practice》2019,60(5):319-322
A 7‐year‐old, 34‐kg, neutered male Labrador retriever was presented with a 1‐year history of intermittent sneezing with occasional left‐sided epistaxis. CT revealed a mass in the left nasal cavity. Histopathological analysis of rhinoscopy‐guided tissue biopsies was consistent with chronic necrotic and ulcerative rhinitis. Surgical debridement by ventral rhinotomy was subsequently performed and histopathological diagnosis was leiomyoma. Complete resolution of the nasal discharge and reduced sneezing frequency were observed after surgery. Fourteen months postoperatively, CT detected no regrowth of the mass. 相似文献
97.
98.
In vitro differentiation of bovine bone marrow‐derived mesenchymal stem cells into male germ cells by exposure to exogenous bioactive factors
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J Cortez J Bahamonde M De los Reyes J Palomino CG Torres OA Peralta 《Reproduction in domestic animals》2018,53(3):700-709
Mesenchymal stem cells (MSC) are multipotent progenitor cells defined by their ability to self‐renew and give rise to differentiated progeny. Previous studies have reported that MSC may be induced in vitro to develop into different types of specialized cells including male gametes. In vitro gamete derivation technology has potential applications as an alternative method for dissemination of elite animal genetics, production of transgenic animals and conservation of endangered species. This study aimed at investigating the in vitro effect of BMP4, TGFβ1 and RA on the potential for germ cell (GC) differentiation of bovine foetal MSC (bfMSC) derived from bone marrow (BM). The effect of BMP4, TGFβ1 and RA was analysed on the expression of pluripotent, GC and male GC markers on bfMSC during a 21‐day culture period. bfMSC cultured under in vitro conditions expressed OCT4, NANOG and DAZL, but lacked expression of mRNA of VASA, STELLA, FRAGILIS, STRA8 and PIWIL2. Treatment with exogenous BMP4 and TGFβ1 induced a transient increase (p < .05) in DAZL and NANOG mRNA levels, respectively. However, exposure to RA was more effective in increasing (p < .05) expression of DAZL and regulating expression of OCT4 and mRNA levels of NANOG. These data suggest that bfMSC may possess potential for early GC differentiation, where OCT4, NANOG and specially DAZL may play significant roles in controlling progression along the GC lineage. 相似文献
99.
Aida Tapia-Rodríguez Antonia Luna-Velasco James A. Field Reyes Sierra-Alvarez 《Water, air, and soil pollution》2012,223(7):3859-3868
Microbial processes have shown promise for the remediation of uranium and nitrate in groundwater impacted by uranium mine tailings. This study investigated the inhibitory impact of uranium(VI) towards different microbial populations in anaerobic biofilms, including methanogenic, denitrifying, and uranium-reducing microorganisms, which are commonly found at uranium bioremediation sites. Results of batch activity bioassays indicated a very distinct level of toxicity depending on the targeted microbial community. U(VI) caused severe inhibition of acetoclastic methanogenesis as indicated by a 50?% inhibiting concentration (IC50) of only 0.16?mM. Denitrifying populations were also impacted by uranium, but their sensitivity depended on the electron donor utilized. Sulfur-oxidizing denitrifiers were the least affected (IC50 for denitrification activity?=?0.32?mM), followed by H2- and acetate-utilizing denitrifiers (IC50 of 0.20 and 0.15?mM, respectively). In contrast, exposure to U(VI) concentrations up to 1.0?mM did not inhibit the rate of U(VI) bioreduction with H2 as electron donor in the presence or absence of nitrate. On the contrary, a considerable increase in the uranium-reducing activity of the denitrifying and methanogenic mixed cultures was observed with increasing uranium concentrations. The results suggest that microorganisms responsible for U(V) reduction could tolerate much higher uranium concentrations compared to the other microbial populations assayed. 相似文献
100.
Deb R. Aryal Violette Geissen Alejandro Ponce‐Mendoza Rodimiro R. Ramos‐Reyes Mathias Becker 《植物养料与土壤学杂志》2012,175(4):553-559
The effects of intensive banana production with high mineral‐fertilizer application and of extensive pastures were compared regarding water quality in a lowland region of SE Mexico. We monitored NO$ _3^- $ , NO$ _2^- $ , and PO43– concentrations in groundwater (80 m depth), subsurface water (5 m depth), and surface water (open‐ditch drainage) at monthly intervals for a one‐year period. Irrespective of the land use, the NO$ _3^- $ concentrations in all water bodies were lower than the threshold value for drinking water and aquatic life. Particularly in areas with intense banana production, the NO$ _2^- $ contents in water exceeded the safety thresholds for drinking water of 1.0 mg L–1 (WHO, 2006) and aquatic ecosystems of 0.2 mg L–1 (OATA, 2008). Water from pastureland showed significantly higher PO43– concentration than that from the banana plantation, indicating a high risk of eutrophication. There is a need to provide recommendations for optimal time and amount of N application in commercial banana production and for limitation of P inputs in pasturelands to avoid further contamination of water bodies. 相似文献