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621.
Marta Bellver Susana Lemos da Costa Begoa Astrain Sanchez Vitor Vasconcelos Ralph Urbatzka 《Marine drugs》2021,19(3)
Obesity is a complex metabolic disease, which is increasing worldwide. The reduction of dietary lipid intake is considered an interesting pathway to reduce fat absorption and to affect the chronic energy imbalance. In this study, zebrafish larvae were used to analyze effects of cyanobacteria on intestinal lipid absorption in vivo. In total, 263 fractions of a cyanobacterial library were screened for PED6 activity, a fluorescent reporter of intestinal lipases, and 11 fractions reduced PED6 activity > 30%. Toxicity was not observed for those fractions, considering mortality, malformations or digestive physiology (protease inhibition). Intestinal long-chain fatty acid uptake (C16) was reduced, but not short-chain fatty acid uptake (C5). Alteration of lipid classes by high-performance thin-layer chromatography (HPTLC) or lipid processing by fluorescent HPTLC was analyzed, and 2 fractions significantly reduced the whole-body triglyceride level. Bioactivity-guided feature-based molecular networking of LC-MS/MS data identified 14 significant bioactive mass peaks (p < 0.01, correlation > 0.95), which consisted of 3 known putative and 11 unknown compounds. All putatively identified compounds were known to be involved in lipid metabolism and obesity. Summarizing, some cyanobacterial strains repressed intestinal lipid absorption without any signs of toxicity and could be developed in the future as nutraceuticals to combat obesity. 相似文献
622.
R Cruz MM Cardoso L Fernandes M Oliveira E Mendes P Baptista S Morais S Casal 《Journal of agricultural and food chemistry》2012,60(32):7777-7784
Espresso spent coffee grounds were chemically characterized to predict their potential, as a source of bioactive compounds, by comparison with the ones from the soluble coffee industry. Sampling included a total of 50 samples from 14 trademarks, collected in several coffee shops and prepared with distinct coffee machines. A high compositional variability was verified, particularly with regard to such water-soluble components as caffeine, total chlorogenic acids (CGA), and minerals, supported by strong positive correlations with total soluble solids retained. This is a direct consequence of the reduced extraction efficiency during espresso coffee preparation, leaving a significant pool of bioactivity retained in the extracted grounds. Besides the lipid (12.5%) and nitrogen (2.3%) contents, similar to those of industrial coffee residues, the CGA content (478.9 mg/100 g), for its antioxidant capacity, and its caffeine content (452.6 mg/100 g), due to its extensive use in the food and pharmaceutical industries, justify the selective assembly of this residue for subsequent use. 相似文献
623.
Marta Kowalska 《山东饲料》2013,(17):24+51
Knowledge of the importance of one country values and symbols, which given culture attaches to some elements or live situations helps when doing business on the foreign market. Values can be defined as standards or rules, which are recognized as valuable and important in life. Values are the reflection of what people really believe in and their attitudes towards the most important aspects of live. Values determine our way of thinking, behaving as well as mirror our cultural background. Symbols play an important role in the intercultural environment. Incorrect usage of some of the symbol can be equal to failure while doing business. 相似文献
624.
Federica Maggio Stefano Pizzirani Teresa Peña Marta Leiva Christopher G. Pirie 《Veterinary ophthalmology》2013,16(1):56-64
Objective The aim of the study was to evaluate the efficacy, outcome, and complications following penetrating sclerokeratoplasty and frozen homologous corneoscleral grafting for the management of extensive canine epibulbar melanocytomas. Methods Medical records of canine patients treated at three different veterinary hospitals between 1999 and 2010 were reviewed. Signalment, location and extent of melanocytomas, recurrence rate, and early and late complications were reported. Patients were re‐examined postoperatively to provide follow‐up information. Results Patients included one intact male, three castrated males, six intact females, and one spayed female, with a median age of 5 years (range, 3–9). German Shepherds were overrepresented. Tumors extended from 2 to 4 clock hours at the limbus and up to 17 mm from clear cornea to globe equator. One case showed iridocorneal angle invasion; corneal involvement was present in all cases, and lipid keratopathy was present in four cases. In two cases, there was incomplete resection owing to tumor extent. Follow‐up time ranged from 3 to 72 months (median, 17 months), with one case of intraocular tumor progression. Early complications included anterior uveitis (11/11), intracameral fibrin (5/11), hyphema (4/11), corneal edema (4/11), exuberant corneal granulation tissue (2/11), focal retinal edema (1/11), dyscoria (1/11), and partial suture dehiscence (1/11). Late complications included corneal fibrosis and/or pigmentation (11/11), faint anterior cortical cataracts (3/11), and lipid keratopathy (1/11). Vision was retained in all cases. Conclusions This technique offers a surgically challenging but effective treatment for extensive epibulbar melanocytomas. In this case series, complications were mild and transient, with preservation of ocular anatomy and function. 相似文献
625.
Diego A Portela Pablo E Otero Martina Biondi Marta Romano Simonetta Citi Tommaso Mannucci Angela Briganti Gloria Breghi Carlos Bollini 《Veterinary anaesthesia and analgesia》2013,40(6):e91-e99
ObjectiveTo determine the needle‐to‐nerve distances during electrical nerve location in dogs at different currents and pulse duration using a peripheral nerve stimulator (PNS) under ultrasound control (US), and the minimal electrical thresholds (MET) necessary to obtain a motor response (MR) after achieving needle‐to‐nerve contact.Study designProspective in vivo experimental trial in a clinical settingAnimalsThirty dogs, scheduled for locoregional anaesthesia of the sciatic nerve.MethodsNeedle‐to‐nerve distance was measured ultrasonographically after obtaining the MR of sciatic nerve with 2, 1 and 0.5 mA and pulse duration 0.1 ms (NS0.1). Thereafter the needle was placed in contact with the nerve and MET was determined. The procedure was repeated with 0.3 ms (NS0.3). Finally the needle was reintroduced to contact the sciatic nerve guided only by US, thus MET‐US was determined. Data were analysed using Kruskal–Wallis or Mann–Whitney tests.ResultsNeedle‐to‐nerve distances were greater when MR was obtained with 2 mA than with 1 and 0.5 mA at 0.1 and 0.3 ms. No significant differences were observed between the needle‐to‐nerve distances using 0.1 or 0.3 ms.The MET [median (range)] was 0.4 (0.18–1.3) mA in NS0.1, 0.32 (0.12–0.8) mA in NS0.3; while MET‐US was 0.7 (0.32–1.5) mA. When the needle contacted the nerve, the MR achieved with currents below 0.3 mA was obtained in 17.2, 40 and 0% of cases using NS0.1, NS0.3 and US respectively.Conclusions and clinical relevanceThe electrical current necessary to obtain a MR decreased as the needle moved towards the nerve. However when the needle tip contacted the nerve, an MR with low current intensity could not be obtained. Thus the absence of motor response at currents below 0.3 mA cannot rule out needle‐epineurium contact. When ultrasound is combined with PNS, it is more important to assess the correct needle position than searching for an MR at low currents. 相似文献
626.
Marta B. Collantes Celina Escartín Karen Braun Ana Cingolani Juan Anchorena 《Strength and Conditioning Journal》2013,66(6):688-699
Although Magellanic meadows have been subject to ungulate herbivory for a long time; they have suffered severe grazing by domestic sheep since the end of the 19th century. We hypothesized that, if protected from grazing, the present dominant dwarf forms would be replaced by taller competitive forms, mainly grasses. We then monitored floristic composition along a gradient of soils over periods of 5 to 16 on seven meadow sites under grazing and, in five, also on exclosures. Initial and final floristic samples were classified with TWINSPAN and ordinated with Detrended Correspondence Analysis (DCA). We also tracked cover changes in life-forms (grasses, dwarf sedges/rushes, rhizomatous helophytes, and cushion shrubs). At the end of the study, we assessed floristic similarity between paired grazed and exclosed treatments, and compared their life-form cover, diversity, biomass, and soil compaction with Student's t and Mann-Whitney's tests. Temporal displacements of composition in ordination space showed the effect of a long drought (DCA axis 1) and of grazing removal (DCA axis 2). Grazing exclusion had a much greater impact in wet meadows–where grasses became the dominant life-form–than in dry meadows. The effect of drought was shown in 1) the expansion of the cushion shrub Azorella trifurcata (Gaertn.) Pers. in both grazed and nongrazed treatments of the drier wetlands; 2) the decrease in Caltha sagittata Cav. in riparian meadows, and its encroachment under grazing in the wettest spring meadow; and 3) the large increase in Poa pratensis L. in exclosed wet meadows. Despite this strong response to environmental conditions, overall results supported the idea that these wetlands are equilibrium systems. Although the drier meadows have crossed an irreversible threshold, the Caltha-encroached wet meadows returned to a grass state in about 4 when protected from grazing. Their resilience suggests that they could be partly restored with rest-rotation grazing. 相似文献
627.
Marta Amat Susana Le Brech Tomàs Camps Carlos Torrente Valentina M. Mariotti José L. Ruiz Xavier Manteca 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(1):19-25
Aggression is one of the most common behavioral problems in dogs and may have important negative effects on public health, human–animal bond, and animal welfare. There is ample evidence showing a negative correlation between serum serotonin concentration and aggressive behavior in a variety of species, including the domestic dogs. This negative correlation is particularly pronounced in dogs that show impulsive aggression. Data obtained in some previous studies suggest that the English cocker spaniel (ECS) is more likely to show impulsive aggression than other breeds. Therefore, the aim of this study was to analyze possible differences in serum serotonin levels between aggressive ECS and aggressive dogs of other breeds. Nineteen ECSs presented for aggression at the Animal Behavior Service (School of Veterinary Science, Barcelona, Spain) were evaluated and compared with 20 aggressive dogs of other breeds attended at the same center. Serum serotonin levels were measured using an enzyme-linked immunosorbent assay method. Statistical analysis was done using the SPSS 15.0 for Windows. Aggressive ECSs had significantly (P < 0.001) lower levels of serum serotonin than aggressive dogs of other breeds (318.6 ± 67.1 and 852.77 ± 100.58 ng/mL, respectively). Variances were not significantly different between ECSs and other breeds (standard deviation = 449.84 ng/mL vs. 292.47 ng/mL, P > 0.05). This finding may explain why ECSs are more likely to show impulsive aggression than other breeds, and suggests that the ECS could be a good model to study the neurophysiologic mechanisms underlying impulsive aggression. 相似文献
628.
629.
Contents Poly(ADP-ribose) polymerase (PARP) synthesizes poly(ADP-ribose) in response to DNA strand breaks using NAD+ as a substrate. It leads to consequences for metabolism not only on a cellular level, but also on a tissue level, among others: NAD+ and ATP depletion. Retention of foetal membranes (RF) in cows is supposed to be connected with the imbalance between production and neutralization of reactive oxygen species, leading to oxidative damage to DNA, lipids and proteins. The aim of this preliminary study was to detect the presence of PARP in bovine placenta and to describe the enzyme with respect to type of placental tissue, time and mode of delivery. Placentomes, collected after spontaneous delivery or caesarian section, were divided into maternal and foetal parts of placenta, homogenized, and subjected to electrophoresis. Cows were divided into six groups as follows: (A) caesarian section before term with RF, (B) caesarian section before term without RF, (C) spontaneous delivery at term with RF, (D) spontaneous delivery at term without RF, (E) caesarian section at term with RF, (F) caesarian section at term without RF. PARP was detected by Western blotting using commercially available bovine anti PARP antibody. Bands referred to as bovine PARP standard were present in all examined tissues as well as the products of its cleavage. However, the patterns of bands were different with respect to type of tissue, time, and mode of delivery. Further experiments on detailed relationship between PARP activity and the process of releasing and retaining of bovine placenta are necessary. 相似文献
630.