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731.
Paula Martínez‐Marcos Melissa Carvajal‐Serna Sofía Lzaro‐Gaspar Rosaura Prez‐P Teresa Muio‐Blanco Jos A. Cebrin‐Prez Adriana Casao 《Reproduction in domestic animals》2019,54(12):1643-1650
The melatonin catabolism is very complex and not completely understood. Melatonin can be metabolized by free radical interaction, but also pseudo‐enzymatically or by enzymatic pathways. We have previously detected the existence of melatonin‐synthesizing enzymes and melatonin receptors MT1 and MT2 in the ram reproductive tract; thus, in order to start to elucidate melatonin catabolism in these organs, we have investigated the presence of the melatonin‐catabolizing enzymes indoleamine 2,3‐dioxygenase (IDO, both IDO1 and IDO2 isoforms) and myeloperoxidase (MPO) in testis, epididymis and accessory glands. Gene expression analyses by real‐time PCR showed the presence of MPO, IDO1 and IDO2 in all the organs of the ram reproductive tract and revealed that MPO is the main melatonin‐catabolizing enzyme, which is mainly expressed in the testis and the bulbourethral glands (p < .05). These results were further corroborated by immunohistochemical staining, and by Western blot. Likewise, MPO was also evidenced in epididymal and ejaculated spermatozoa by indirect immunofluorescence and Western blot. In conclusion, melatonin‐catabolizing enzymes MPO, IDO1 and IDO2 are expressed in the ram reproductive tract, and MPO is the most expressed one, mainly in the testis and the bulbourethral glands. The presented results warrant further studies on the function of these enzymes and their melatonin‐metabolizing activity. 相似文献
732.
Claudio De Liberato Federica Berrilli Teresa Boss Adele Magliano Margherita Montalbano Di Filippo David Di Cave Mariano Sigismondi Annunziata Cannavacciuolo Paola Scaramozzino 《Zoonoses and public health》2019,66(4):377-381
Swimmer's itch is caused by the penetration of free‐swimming larvae of trematodes of the family Schistosomatidae in human skin. It is usually reported in people engaged in recreational water activities in freshwater bodies and in most of cases, it is provoked by bird schistosomes of the genus Trichobilharzia. In the summer 2017, many cases of dermatitis were recorded in people bathing in the waters of the Albano Lake (Rome, Italy) and a parasitological investigation was carried out in order to ascertain the causative agent of these cases. Snails of the family Lymnaeidae, natural intermediate hosts of bird schistosomes, were collected from lake shallow waters to detect the presence of trematodes of the genus Trichobilharzia. Pools of maximum 10 snails were placed in Petri dishes, and cercarial emergence was stimulated exposing snails to strong artificial light intensity at 25°C. Three hundred and thirty‐seven snails were collected and screened for the shedding of cercariae. Furcocercariae of the family Schistosomatidae, with a morphology overlapping that of the genus Trichobilharzia, were detected in seven Petri dishes. Assuming that in each positive Petri dish just one snail was shedding furcocercariae, the minimum infectious rate was 2.1%. Molecular analysis of furcocercariae allowed ascribing them to the species Trichobilharzia franki. Snails of the species Radix auricularia were identified as intermediate hosts of the parasite. This is the second record of T. franki causing cercarial dermatitis in Central Italy, the third in Italy. The 2017 was in Italy exceptionally warm and dry. Trematodes are sensitive to changes in temperature, being cercarial production and emission rates temperature dependent. Small increases in water temperature would speed up parasite development and transmission, leading to a manifold increase in cercarial emergence. Moreover, high temperatures raise chances to acquire the infection, due to increased time spent in water by people. 相似文献
733.
734.
Margaret S. White Brian G. Tavernia Patrick B. Shafroth Teresa B. Chapman John S. Sanderson 《Landscape Ecology》2018,33(12):2205-2220
Context
Habitat complexity in rivers is linked to dynamic fluvial conditions acting at various spatial scales. On regulated rivers in the western United States, tributaries are regions of high energy and disturbance, providing important resource inputs for riparian ecosystems.Objectives
This study investigated spatial patterns and extents of tributary influence on riparian habitat complexity in the near channel zone along regulated reaches of the Colorado (>?200 km) and Dolores Rivers (~?300 km) in the western United States. Because tributary confluences are regions of increased dynamism, we hypothesized that: (1) geomorphic and land cover complexity would be greatest close to tributary junctions and decrease with distance from tributaries; and (2) patterns in complexity would vary across different sized spatial units.Methods
Using a combination of remote sensing and spatial analysis, we classified fluvial features and land cover classes to investigate patterns longitudinally at 10-, 25-, and 100-m spatial units in the near channel zone of two regulated rivers.Results
Using change point analysis and randomization tests, we detected shifts in riparian habitat complexity closer to tributary junctions. Patterns varied across 10-, 25-, and 100-m spatial units in the near channel zone, with significance (p?≤?0.05) recorded for 10- and 25-m spatial units.Conclusions
Tributary junctions deliver critical resource inputs on regulated systems, providing for increased geomorphic and land cover diversity upstream and downstream of tributaries. We found that patterns of response were non-linear and discontinuous, varying across spatial units and potentially influenced by the degree of mainstem flow regulation.735.
Cristina López‐Fando Maria Teresa Pardo Fernandez Hans‐Richard Wegener 《Archives of Agronomy and Soil Science》2013,59(6):489-505
Im IOSDV Madrid wird seit 1984 die kombinierte Wirkung von Stallmist, Stroh, Zwischenfrucht und mineralischer N‐Düngung in der Fruchtfolge Sorghum‐Weizen‐Gerste auf einem semiariden Standort in der zentralspanischen Meseta auf einem Calcic Luvisol geprüft. Die Ergebnisse zeigen, dass die Witterungsbedingungen die Erträge wesentlich stärker beeinflussen als die Behandlungsvarianten. Durch die sehr geringen Niederschläge während der dritten Rotation waren die Gersten‐ und Weizenerträge unabhängig von der Düngung sehr niedrig, während unter optimalen Niederschlagsbedingungen in der ersten und zweiten Rotation die Weizen‐ und Gerstenerträge mit steigender N‐Düngung zunahmen und ihr Optimum bei der Stickstoffdüngungsstufe N3 aufwiesen; allerdings zeigte nur die Gerste eine Reaktion auf die gleichzeitige Anwendung organischer Dünger. Während der vierten Rotation wurden die Trockenmasse‐Erträge bei Weizen und Gerste durch organische Düngung bis zur Stufe N2 erhöht, während höhere Mineral‐N‐Gaben die Erträge negativ beeinflussten. Bei Sorghum traten, bedingt durch die extremen Niederschlagsbedingungen, erhebliche Schwierigkeiten auf, die sich in einem sehr niedrigen Korn‐Stroh‐Verhältnis widerspiegelten und keinerlei signifikanten Zusammenhang zu den Behandlungsvarianten erkennen liessen. 相似文献
736.
Simone Magni Monica Gaetani Lisa Caturegli Claudio Leto Teresa Tuttolomondo Salvatore La Bella 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(8):722-733
Breeding of turf bermudagrass (Cynodon (L.) Rich.) has made available a broad range of turf varieties with unique morphological and growth traits. Rapid establishment is necessary in order to provide the performance of a mature turf cover in the shortest time possible. The aims of the research were: (1) to determine variation of growth, morphological and biomass traits in bermudagrass accessions belonging to different phenotypic groups during establishment and (2) to relate such variations to establishment speed in order to assess whether contrasting phenotypic traits could induce different establishment patterns in bermudagrass or if a general establishment predictor can be identified for cultivars and ecotypes belonging to the same taxon. Plant material included 44 accessions of bermudagrasses that were grouped in ‘Wild’, ‘Improved’ ‘Hybrid’ and ‘Dwarf types’. Single spaced plants were transplanted in field plots in two locations in Italy (Pisa and Palermo) and allowed to establish without mowing. The following traits were determined: stolon growth rate, internode length, internode diameter and internode volume, phytomer dry weight, leaf width, colour, seed head production, above ground dry biomass, shoot density, horizontal stem density and node density. Establishment speed of accessions was also determined. Stolon growth rate was found to be the only parameter strongly correlated to establishment speed across all entries and for each of the phenotypic groups. Based on these results, stolon growth rate could be assumed as a good predictor of establishment speed for cultivars and ecotypes belonging to the Cynodon genus. 相似文献
737.
Nair Dahmer Maria Teresa Schifino-Wittmann Divanilde Guerra Roberto Luis Weiler 《Genetic Resources and Crop Evolution》2013,60(1):377-383
Mimosa scabrella Bentham, popularly known as “bracatinga” in Brazil, is a very important multipurpose tree especially in the southern region of the country, where it occurs naturally in plant associations called “bracatingais”. The species is presently in danger of losing genetic variability as it normally occurs in regions subjected to intense urbanization, industrialization, agriculture and cattle raising. Aiming at broadening the knowledge about the species we have investigated cytogenetic characteristics and genetic diversity among natural populations. The results show that all populations are tetraploid (2n = 4× = 52) and that there is a high genetic diversity among the populations. There is still time to avoid genetic erosion of M. scabrella if the areas where the species occurs are protected. 相似文献
738.
Abstract The humic acids (HA) from composted and uncomposted city refuse (CR) were characterized by degradative (oxidation with persulphate and permanganate) and non-degradative techniques (FT-IR and 13C-NMR) in order to analyze the effect of the composting process on these HA. They were also compared with commercial HA extracted from leonardite. The carboxyl and carbonyl group content of the HA from CR increased slightly during composting. Since the HA from the composted CR showed a lower N and H content, the FT-IR spectra showed a lower intensity in the bands corresponding to peptides and carbohydrates. Differences were revealed when the HA from both CR were compared with those from leonardite which showed a much lower N and H content and a less aliphatic character. The percentage of degraded products by persulphate was higher for the HA from uncomposted CR. For the HA from both CR the major components among the oxidation products were dicarboxylic acids and normal fatty acids. In the leonardite HA, the major components consisted of benzene polycarboxylic acids. 13C-NMR revealed an attenuation of the aliphatic character of the HA from CR with composting. 相似文献
739.
Patrícia Susano Joana Silva Celso Alves Alice Martins Helena Gaspar Susete Pinteus Teresa Mouga Mrcia Ines Goettert
eljko Petrovski Luís B. Branco Rui Pedrosa 《Marine drugs》2021,19(3)
The ever-increasing interest in keeping a young appearance and healthy skin has leveraged the skincare industry. This, coupled together with the increased concern regarding the safety of synthetic products, has boosted the demand for new and safer natural ingredients. Accordingly, the aim of this study was to evaluate the dermatological potential of the brown seaweed Carpomitra costata. The antioxidant, anti-enzymatic, antimicrobial, photoprotective and anti-inflammatory properties of five C. costata fractions (F1–F5) were evaluated. The ethyl acetate fraction (F3) demonstrated the most promising results, with the best ability to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals (EC50 of 140.1 µg/mL) and the capacity to reduce reactive oxygen species (ROS) production promoted by UVA and UVB radiation in 3T3 cells, revealing its antioxidant and photoprotective potential. This fraction also exhibited the highest anti-enzymatic capacity, inhibiting the activities of collagenase, elastase and tyrosinase (IC50 of 7.2, 4.8 and 85.9 µg/mL, respectively). Moreover, F3 showed anti-inflammatory potential, reducing TNF-α and IL-6 release induced by LPS treatment in RAW 264.7 cells. These bioactivities may be related to the presence of phenolic compounds, such as phlorotannins, as demonstrated by NMR analysis. The results highlight the potential of C. costata as a source of bioactive ingredients for further dermatological applications. 相似文献