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871.
Change in Sox9 protein localization through gonad development in Russian sturgeon (Acipenser gueldenstaedtii)
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Maciej Kamaszewski Aleksandra Gosk Marek Skrobisz Teresa Ostaszewska 《Aquaculture Research》2017,48(6):3111-3120
The Russian sturgeon is a highly prized species reared in aquaculture. The process of gonad development in this critically endangered species is poorly understood. The aim of this study was to describe the localization of Sox9 protein during gonad development of the Russian sturgeon from the day of hatching to the 1440 day post hatching (dph). The larvae at age 1, 10, 25 dph and prepared gonads of 300, 720, 1440 dph individuals were immunohistochemistry‐stained for Sox9 detection. Sox9‐positive regions were detected in larvae in primordial germ cells cytoplasm. Analysis of 300 dph sturgeon gonads revealed the presence of the Sox9 protein in cytoplasm of some oocytes in the chromatin nucleus stage. In testes at 720 dph, Sox9 was observed in the cytoplasm of type A and early B spermatogonias. In the ovaries, Sox9 was observed in the cytoplasm of diplotene oocytes and prefollicular cells. In testes of 1440 dph sturgeon, Sox9 was present in the nucleus of the spermatocytes and in types A and B spermatogonias cytoplasm. Analysis of ovaries at 1440 dph reveals multiple diplotene oocytes with a Sox9‐positive cytoplasm. Furthermore, in 720 and 1440 dph, sturgeon presence of intersexual gonads was detected. In intersex gonads, Sox9 was observed in the cytoplasm of diplotene oocytes and type A spermatogonias. This study may be the first attempt to determine Sox9 protein localization during ontogenesis of the Russian sturgeon. Localization of Sox9 protein may become a useful marker of the maturation level in testis of the Russian sturgeon. 相似文献
872.
Effects of natural phenolic compounds on the antioxidant activity of lactoferrin in liposomes and oil-in-water emulsions 总被引:2,自引:0,他引:2
Medina I Tombo I Satué-Gracia MT German JB Frankel EN 《Journal of agricultural and food chemistry》2002,50(8):2392-2399
The effect of natural phenolic compounds on the antioxidant and prooxidant activity of lactoferrin was studied in liposomes and oil-in-water emulsions containing iron. The antioxidants tested with lactoferrin were alpha-tocopherol, ferulic acid, coumaric acid, tyrosol, and natural phenolic extracts obtained from three different extra-virgin olive oils and olive mill wastewater. The natural extracts of olive oils and mill wastewaters were composed mainly of polyphenols and simple phenolics, respectively. Lipid oxidation at 30 degrees C was determined by the formation of hydroperoxides and fluorescent compounds resulting from oxidized lipid interactions. All phenolic compounds showed synergistic properties in reinforcing the antioxidant activity of lactoferrin in lipid systems containing iron. The highest synergistic effects were observed for the phenolic extracts rich in polyphenols of extra-virgin olive oils and lactoferrin. This synergistic effect was higher in liposomes than in emulsions. 相似文献
873.
Patricia María Rodríguez-González John Christopher Stella Filipe Campelo Maria Teresa Ferreira António Albuquerque 《Forest Ecology and Management》2010
In forested wetlands, hydrology exerts complex and sometimes compensatory influences on tree growth. This is particularly true in semi-arid ecosystems, where water can be both a limiting resource and a stressor. To better understand these relationships, we studied hydrologic and edaphic controls on the density, growth, tree architecture and overall productivity of forested wetlands dominated by the tree species Alnus glutinosa and Salix atrocinerea in Southern Europe. We sampled 49 plots set within 21 stands in the Atlantic coastal zone of the Iberian Peninsula, and quantified woody composition, size structure (diameter and height), and radial growth using dendrochronology. Plots were grouped into three saturation classes to compare tree growth characteristics (tree density, degree of sprouting, live basal area and productivity) across levels of saturation. We used Principal Component Analysis (PCA) to create integrated explanatory factors of hydrology, soil nutrient status and soil texture for use in linear mixed models to predict stand characteristics. Increased site saturation favoured a shift in species dominance from Alnus to Salix and resulted in a higher degree of multi-stemmed tree architecture (‘shrubbiness’), particularly for Alnus. Radial growth was negatively correlated with long-term soil saturation; however, annual productivity on a per-tree basis varied by species. Alnus growth and tree density were negatively correlated with waterlogging and fine-textured soils, possibly due to anaerobiosis in the rooting zone. In contrast, Salix growth was more influenced by nutrient limitation. Overall site productivity as measured by annual basal area increment decreased with prolonged saturation. In summary, soil saturation appears to act as a chronic stressor for tree species in this ecosystem. However, these species persist and maintain a dominant canopy position in the most permanently flooded patches through increased sprouting, albeit at a reduced rate of overall biomass accumulation relative to well-drained sites. The diversity in functional responses among wetland forest species has important implications for the conservation and management of these ecosystems. The sustainable management of these ecosystems is directly tied to their vulnerability to changing hydrological conditions. Non-equilibrium modifications to the hydrologic regime from land use and climate change, which are particularly severe in semi-arid regions, may further decrease productivity, integrity and resilience in these stress-adapted communities. 相似文献
874.
ngel Martín Ortiz‐Estrada Marcel Martínez‐Porchas Luis Rafael Martínez‐Crdova Francisco Vargas‐Albores Armando Burgos‐Hernandz Susana María Scheuren‐Acevedo Teresa Gollas‐Galvn 《Aquaculture Research》2021,52(1):334-344
Biofilm‐based aquaculture systems constitute a promising alternative for intensive shrimp rearing. Microorganisms forming biofilms can recycle the nitrogen compounds the production units improving the water quality while using zero or limited water exchange. This study aimed to compare the taxonomic profiles and the predicted functions related to the transformation of nitrogenous compounds between a heterotrophic‐ (HtB) and a probiotic biofilm (PrB), and the effect of these on the water quality and the productive response of cultured shrimp. Libraries of the 16S‐rRNA gene (V3‐V4 region) were prepared and sequenced to be used as a taxonomic biomarker. Analysis of metagenomic datasets revelated that genera Halomonas, Planctomycetes and Rhodopirellula were the most abundant genera in HtB; meanwhile, Bacillus, Halobacillus and Flavobacterium dominated in PrB. Regarding nitrogen metabolism, the proportion of genes encoding enzymes catalyzing the six pathways shaping the nitrogen metabolism showed differences between biofilms, which could also explain the difference in water quality between treatments. Concerning the productive response of shrimp, no significant differences were detected except for survival, which was higher in PrB. Finally, the results suggest that biofilms harbour functions for nitrogen metabolism, including dissimilatory nitrate reduction, assimilatory nitrate reduction, denitrification, nitrification, nitrogen fixation and anammox; however, the balance of these functional capabilities seems to be relevant to maintain water quality. 相似文献
875.
Joshua G. Levinson DVM ; Jennifer L. Bouma VMD DACVR ; Gary C. Althouse DVM MS PhD DACT Teresa M. Rieser VMD DACVECC 《Journal of Veterinary Emergency and Critical Care》2009,19(5):496-500
Objective – To compare the histopathologic diagnosis in dogs with spontaneous hemoperitoneum when abdominal ultrasonographic examination detects a solitary versus multiple lesions.
Design – Retrospective cross-sectional study.
Setting – Private veterinary hospital.
Animals – Client-owned dogs presented with spontaneous hemoperitoneum between March 1, 2003 and June 1, 2008.
Interventions – Dogs were divided into 2 groups based on presence of a solitary or multiple abdominal ultrasonographic lesions. Prevalences were compared between groups for malignancy and specifically hemangiosarcoma.
Measurements and Main Results – Ten of 31 (32%) dogs had a solitary abdominal ultrasonographic lesion and 21 of 31 (68%) had more than 1 lesion. The bleeding tissue was characterized as malignant in 8 of 10 (80%) dogs with solitary lesions and 17 of 21 (81%) dogs with multiple lesions; there was no significant difference ( P =1.0) between groups. In this study no association ( P =0.26) was found between the number of abdominal ultrasonographic lesions observed and subsequent diagnosis of hemangiosarcoma.
Conclusions – Solitary abdominal ultrasonographic lesions in dogs with spontaneous hemoperitoneum do not necessarily indicate a lower prevalence of malignancy. 相似文献
Design – Retrospective cross-sectional study.
Setting – Private veterinary hospital.
Animals – Client-owned dogs presented with spontaneous hemoperitoneum between March 1, 2003 and June 1, 2008.
Interventions – Dogs were divided into 2 groups based on presence of a solitary or multiple abdominal ultrasonographic lesions. Prevalences were compared between groups for malignancy and specifically hemangiosarcoma.
Measurements and Main Results – Ten of 31 (32%) dogs had a solitary abdominal ultrasonographic lesion and 21 of 31 (68%) had more than 1 lesion. The bleeding tissue was characterized as malignant in 8 of 10 (80%) dogs with solitary lesions and 17 of 21 (81%) dogs with multiple lesions; there was no significant difference ( P =1.0) between groups. In this study no association ( P =0.26) was found between the number of abdominal ultrasonographic lesions observed and subsequent diagnosis of hemangiosarcoma.
Conclusions – Solitary abdominal ultrasonographic lesions in dogs with spontaneous hemoperitoneum do not necessarily indicate a lower prevalence of malignancy. 相似文献
876.
Juniperus thurifera L. is an endemic conifer of the western Mediterranean Basin where it is subjected to a severe climatic stress characterized by low winter temperatures and summer drought. Given the trend of increased warming-induced drought stress in this area and the climatic sensitivity of this species, we expect a negative impact of climate change on growth and ecophysiological performance of J. thurifera in the harsh environments where it dominates. To evaluate this, we measured long- and short-term radial growth using dendrochronology, photosynthesis and water-use efficiency in males, females and juveniles in three sites in Central Spain. Climate was monitored and completed with historical records. Mean annual temperature has increased +0.2?°C per decade in the study area, and the main warming trends corresponded to spring (+0.2?°C per decade) and summer (+0.3?°C per decade). Radial growth and maximum photosynthesis peaked in spring and autumn. Positive photosynthetic rates were maintained all year long, albeit at reduced rates in winter and summer. Radial growth was enhanced by wet conditions in the previous autumn and by warm springs and high precipitation in summer of the year of tree-ring formation. Cloud cover during the summer increased growth, while cloudy winters led to impaired carbon gain and reduced growth in the long term. We argue that maintenance of carbon gain under harsh conditions (low winter temperatures and dry summer months) and plastic xylogenesis underlie J. thurifera's ability to profit from changing climatic conditions such as earlier spring onset and erratic summer rainfall. Our results highlight that not only the magnitude but also the sign of the impact of climate change on growth and persistence of Mediterranean trees is species specific. 相似文献
877.
Margherita Santoni Leonardo Verdi Shamina Imran Pathan Marco Napoli Anna Dalla Marta Francesca Romana Dani Gaio Cesare Pacini Maria Teresa Ceccherini 《Soil Use and Management》2023,39(1):588-605
The implementation of environmentally friendly agricultural policies has increased the need to compare agricultural aspects of conventional (CON) and organic farming (ORG) systems. The objective of the present work was to compare the effects of an organic and conventional long-term experiment on bacterial and fungal biomass and activity, as well as soil CO2 emission and readily available nitrogen forms in a soil cultivated with Helianthus annuus L. The microbial biomass was more active and abundant in ORG as well as soil CO2 emission. Despite being less abundant, fungi were more active than bacteria in both ORG and CON experiments. 16S rRNA gene sequencing showed that the ORG treatment had a significantly greater bacterial richness than CON. Cyanobacteria, Actinobacteria and Proteobacteria were the most abundant phyla contributing more than others to the differences between the two systems. Moreover, the soil and content was not significantly different between ORG and CON, while was less in ORG. ORG sunflower yield was significantly less compared with CON. While much remains to be discovered about the effects of these agricultural practices on soil chemical properties and microbial diversity, our findings may contribute to this type of investigation. 相似文献
878.
Teresa De Pilli Roma Giuliani Barbara F. Carbone Antonio Derossi Carla Severini 《Cereal Chemistry》2005,82(5):494-498
Doughs made from wheat and almond flours, water, and five types of emulsifiers commonly used in confectionary and bakery products (soy lecithin, sucrose esters, mono‐glycerides, mono‐ and di‐glycerides of fatty acids, and diacetyl tartaric acid esters of monoglycerides [DATEM]) were studied. To evaluate the additive ability to retain the fatty fraction during the extrusion process, electrical conductivity was measured and fat loss (%) that occurs during extrusion processing was determined. The electrical conductivity measurements showed that the lower and better concentration of soy lecithin and mixed mono‐ and di‐glycerides of fatty acids to obtain an oil‐water emulsion was 0.2 g/100 g of dough, while for sucrose esters and mono‐glycerides of fatty acids, it was 0.7 g/100 g of dough. No efficacy for DATEM was observed. The fat loss results showed that sucrose esters were the most suitable emulsifiers for retaining the fatty fraction during extrusion processing, even at a very low amounts (2 g/kg of dough). 相似文献
879.
Sara Belluco Giuseppe Marano Thibaut Lurier Giancarlo Avallone Chiara Brachelente Stefano Di Palma Roberta Rasotto Kerstin Baiker Andreas Beineke Anna Oevermann Frauke Seehusen Fabiano José Ferreira de Sant'Ana Patrizia Boracchi Martí Pumarola Maria Teresa Mandara 《Veterinary and comparative oncology》2023,21(4):685-699
Canine meningiomas are currently graded using the human grading system. Recently published guidelines have adapted the human grading system for use in dogs. The goal of this study was to validate the new guidelines for canine meningiomas. To evaluate the inter-observer agreement, 5 veterinary surgical pathologists graded 158 canine meningiomas following the human grading system alone or with the new guidelines. The inter-observer agreement for histologic grade and each of the grading criteria (mitotic grade, invasion, spontaneous necrosis, macronucleoli, small cells, hypercellularity, pattern loss and anaplasia) was evaluated using the Fleiss kappa index. The diagnostic accuracy (sensitivity and specificity) was assessed by comparing the diagnoses obtained with the 2 grading systems with a consensus grade (considered the reference classification). The consensus histologic grade was obtained by agreement between 4 experienced veterinary neuropathologists following the guidelines. Compared with the human grading alone, the canine-specific guidelines increased the inter-observer agreement for: histologic grade (κ = 0.52); invasion (κ = 0.67); necrosis (κ = 0.62); small cells (κ = 0.36); pattern loss (κ = 0.49) and anaplasia (κ = 0.55). Mitotic grade agreement remained substantial (κ = 0.63). The guidelines improved the sensitivity in identifying grade 1 (95.6%) and the specificity in identifying grade 2 (96.2%) meningiomas. In conclusion, the new grading guidelines for canine meningiomas are associated with an overall improvement in the inter-observer agreement and higher diagnostic accuracy in diagnosing grade 1 and grade 2 meningiomas. 相似文献