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31.
Comparison of equine bone marrow-, umbilical cord matrix and amniotic fluid-derived progenitor cells
Lovati AB Corradetti B Lange Consiglio A Recordati C Bonacina E Bizzaro D Cremonesi F 《Veterinary research communications》2011,35(2):103-121
The aim of the study was to compare in vitro the stemness features of horse progenitor cells derived from bone marrow (BM-MSCs),
amniotic fluid (AF-MSCs) and umbilical cord matrix (EUC-MSCs). It has been suggested that there may be a stem cell population
within both umbilical cord matrix and amniotic fluid. However, little knowledge exists about the characteristics of these
progenitor cells within these sources in the equine species. This study wanted to investigate an alternative and non-invasive
stem cell source for the equine tissue engineering and to learn more about the properties of these cells for future cell banking.
Bone marrow, umbilical cord and amniotic fluid samples were harvested from different horses. Cells were analyzed for proliferation,
immunocytochemical, stem cell gene expression and multilineage plasticity. BM- and AF-MSCs took similar time to reach confluence
and showed comparable plating efficiency. All cell lines expressed identical stem cell markers and capability to differentiate
towards osteogenic lineage. Almost all cell lines differentiated into the adipogenic lineage as demonstrated by cytochemical
staining, even if no adipose gene expression was detectable for AF-MSCs. AF- and EUC-MSCs showed a limited chondrogenic differentiation
compared with BM-MSCs as demonstrated by histological and biochemical analyses. These findings suggest that AF-MSCs appeared
to be a readily obtainable and highly proliferative cell line from an uninvasive source that may represent a good model system
for stem cell biology. More studies are needed to investigate their multilineage potential. EUC-MSCs need to be further investigated
regarding their particular behavior in vitro represented by spheroid formation. 相似文献
32.
Heckenberger MJ Kuikuro A Kuikuro UT Russell JC Schmidt M Fausto C Franchetto B 《Science (New York, N.Y.)》2003,301(5640):1710-1714
Archaeology and indigenous history of Native Amazonian peoples in the Upper Xingu region of Brazil reveal unexpectedly complex regional settlement patterns and large-scale transformations of local landscapes over the past millennium. Mapping and excavation of archaeological structures document pronounced human-induced alteration of the forest cover, particularly in relation to large, dense late-prehistoric settlements (circa 1200 to 1600 A.D.). The findings contribute to debates on human carrying capacity, population size and settlement patterns, anthropogenic impacts on the environment, and the importance of indigenous knowledge, as well as contributing to the pride of place of the native peoples in this part of the Amazon. 相似文献
33.
Livia Lucentini Antonella Palomba Hovirag Lancioni Lilia Gigliarelli Mauro Natali Fausto Panara 《Fisheries Research》2006,80(2-3):251-262
Northern pike (Esox lucius) is not considered an endangered species in Italy, but since recent studies indicate the decline of this population, conservation and management strategies based on the genetic differentiation of natural northern pike populations are needed. In this paper, genetic diversity was analysed in 10 Italian and 2 East European northern pike populations by means of seven microsatellite loci. Data indicated an appreciable genetic differentiation, in spite of a low genetic variation, and agreed with the low level of genetic polymorphism already observed for this species in North America and North Europe. Results of statistical tests revealed genetic peculiarities of the Italian populations, even though signals of recent contact between populations were found and discussed in relation to anthropic impacts, particularly to the stocking practice. This investigation represents the first approach to the knowledge of the genetic variability of Italian pike populations using microsatellite markers, and reported results could be of interest for future management and conservation programmes of this species in Italy. 相似文献
34.
Ivairton Monteiro Santos Fausto Guzzo da Costa Carlos Eduardo Cugnasca Jó Ueyama 《Precision Agriculture》2014,15(3):290-303
The efficient application of low cost pesticides is a challenge for agricultural production. Pesticide drift is a major cause of environmental contamination. At the time of application, it is essential to know the environmental conditions, such as wind, temperature and humidity to minimize contamination. This study proposes the use of wireless sensor networks in a support and control system for crop spraying and three cases of use are put forward. In the first case, the sensor network evaluates environmental data at the time of application to notify the user if the environmental conditions are suitable. The second use evaluates the wind speed and direction to suggest corrections in the path of a spray vehicle. Due to this alteration in the path, the pesticide is applied solely in the appropriate area. The final use involves collecting samples and analyzing the quality of crop spraying by evaluating the deposition of the pesticide over the crop. Through computer simulations, wireless sensor networks are shown to be useful in crop spraying operation to minimize and to control pesticide drift, to improve the quality of application, to reduce environmental contamination and to save time and money. 相似文献
35.
Monção Flávio Pinto Santana Pedro Felipe Júnior Vicente Ribeiro Rocha Ruas José Reinaldo Mendes Rigueira João Paulo Sampaio Borges Lucas Daniel Alcântara de Castro Menezes Gustavo Chamon Sousa Thais Eleonora Santos da Costa Maria Dulcinéia Oliveira Laura Lúcia Santos de Queiroz Fausto Expedito 《Tropical animal health and production》2020,52(1):141-149
Tropical Animal Health and Production - The quantitative feed restriction of lactating cows has been used in intensive production systems as a strategy to reduce production costs. However, the... 相似文献
36.
Quercus ilex (L.) leaves emit monoterpenes, particularly alpha-pinene, beta-pinene and sabinene. Apart from the monoterpene pools that are stored in specialized structures and have a clear defensive or attractive role, the function of monoterpenes in Q. ilex leaves is unknown. We tested whether monoterpenes have an antioxidant role, as has previously been found for isoprene in isoprene-emitting leaves. We exposed Q. ilex leaves to either mild and repeated ozone exposure (Experiment I) or to a single acute ozone exposure (Experiment II) at temperatures ranging between 20 and 32 degrees C. Both ozone treatments rapidly stimulated monoterpene synthesis, but had no effect on photosynthesis and caused no visible damage to leaves maintained at 25, 30 or 32 degrees C. Ozone inhibited both photosynthesis and monoterpene synthesis in leaves maintained at 20 degrees C. To characterize the relationship between monoterpenes and ozone-induced damage, we fed detached leaves fosmidomycin, a selective inhibitor of isoprene synthesis. Fosmidomycin caused rapid and complete inhibition of monoterpene emissions in leaves maintained at 30 degrees C, confirming that monoterpenes are synthesized by the same biochemical pathway as isoprene. However, over the experimental period, fosmidomycin did not affect concentrations of compounds that are formed from chloroplastic isoprenoids and that might have conferred antioxidant protection, either directly (carotenoids) or indirectly (chlorophylls, xanthophylls). In leaves whose monoterpene synthesis had been inhibited by fosmidomycin, ozone rapidly and significantly inhibited photosynthesis and increased the production of hydrogen peroxide and malonyldialdehyde. We conclude that monoterpenes produced by Q. ilex leaves share the same biosynthetic pathway and function as isoprene. Furthermore, all volatile isoprenoids may have similar antioxidant properties and may be stimulated by the same stress-inducing conditions. 相似文献
37.
Rodolfo Araya Villalobos William G. González Ugalde Fausto Camacho Chacón Patricia Sánchez Trejos Daniel G. Debouck 《Genetic Resources and Crop Evolution》2001,48(3):221-232
Interest in bean genetic resources of Central America has resumed because of disease pressures (e.g., web blight, BGMV) and limitations of current bean varieties. As most of the diversity in landraces has been explored, focus is now on the exploration of wild forms of the primary gene pool and wild species of the secondary gene pool. A germplasm collection was carried out in the field and resulted in the collection of 29 wild populations for six Phaseolus species; it complemented field work done in 1987. Nine more populations were found for P. costaricensis, 10 for wild P. lunatus, one for P. oligospermus, one for P. tuerckheimii, four for wild P. vulgaris and four for P. xanthotrichus. Ninety-three herbarium voucher specimens were collected for 19 populations of the six species (deposited at CR). These results confirm the presence of wild P. vulgaris on both slopes of the central valley of Costa Rica, namely in the life zones bh-MB and bmh-P, and of P. costaricensis in the life zone bmh-MB. These life zones of limited range in Costa Rica have been heavily modified, thus fully justifying the germplasm collection for ex situ conservation. For both species the range of distribution in Costa Rica has been almost completely sampled. The life characteristics of each species that are relevant for their conservation in situ are briefly reviewed. Distribution ranges of each wild bean species are compared with the present extension of national parks, protected areas and fauna/flora sanctuaries, and suggestions for expanding such protected areas are made. 相似文献
38.
Marcello Vitale Elisabetta Salvatori Francesco Loreto Silvano Fares Fausto Manes 《Water, air, and soil pollution》2008,189(1-4):113-125
The combined effect of water stress and ozone (O3) on stomatal O3 flux, damage to photosynthesis, and detoxification by biogenic volatile organic compounds (BVOC) in Quercus ilex leaves was studied. A 4-weeks O3 exposure (250 ppb, 4 h per day) caused a reduction of photosynthesis and stomatal conductance, which was fully recovered 1 week after the end of the treatment, in well-watered and water-stressed plants. Measurements of stomatal O3 flux revealed a low stomatal flux of the pollutant, which became minimal after stomatal closure caused by water stress. An induction of volatile monoterpenes, important compounds in the O3 scavenging system in Q. ilex, and a burst of lipoxygenase compounds (LOX), which are released as gaseous by-products of membrane peroxidation, was observed after 2–3 weeks of O3 fumigation. However, these compounds were also released in control leaves that were exposed to ozone only briefly, to determine stomatal O3 flux. The low stomatal flux that occurred in water stress conditions helped avoiding permanent damage to Q. ilex leaves, although during the O3 treatment photosynthesis was severely limited by stomatal closure. In well-watered plants, O3 fumigation caused a noticeable increase of nocturnal stomatal conductance. If confirmed on adult plants under field conditions, this effect can imply larger flux of O3 at night and possible detrimental effects of O3 on leaf functions in plants exposed to high nocturnal O3 levels. 相似文献
39.