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1.
Marine biofouling is an epibiotic biological process that affects almost any kind of submerged surface, causing globally significant economic problems mainly for the shipping industry and aquaculture companies, and its prevention so far has been associated with adverse environmental effects for non-target organisms. Previously, we have identified bromosphaerol (1), a brominated diterpene isolated from the red alga Sphaerococcus coronopifolius, as a promising agent with significant antifouling activity, exerting strong anti-settlement activity against larvae of Amphibalanus (Balanus) amphitrite and very low toxicity. The significant antifouling activity and low toxicity of bromosphaerol (1) motivated us to explore its chemistry, aiming to optimize its antifouling potential through the preparation of a number of analogs. Following different synthetic routes, we successfully synthesized 15 structural analogs (2–16) of bromosphaerol (1), decorated with different functional groups. The anti-settlement activity (EC50) and the degree of toxicity (LC50) of the bromosphaerol derivatives were evaluated using cyprids and nauplii of the cirriped crustacean A. amphitrite as a model organism. Derivatives 2, 4, and 6–16 showed diverse levels of antifouling activity. Among them, compounds 9 and 13 can be considered as well-performing antifoulants, exerting their activity through a non-toxic mechanism.  相似文献   
2.
The feed provided to breeding fish is one of the main factors influencing the quality of fish gametes. This study was carried out to evaluate the influence of ascorbic acid on growth, haematological parameters and sperm quality of Lebranche mullet males (Mugil liza). Six diets with different levels of ascorbic acid (0; 53; 107; 216; 482 and 708 mg/kg) were tested in triplicate for 75 days. During spermiation (first gonadal maturation), 144 individuals (205.7 ± 11.5 g and 25.7 ± 0.4 cm) were randomly distributed in 18 experimental tanks. Growth parameters were evaluated at the beginning and end of the experiment. Fish blood was collected to analyse glucose, total protein and erythrocyte count (EC) (n = 9). Fish (n = 12) from each treatment were euthanized to determine hepatosomatic index (HSI) and gonadosomatic index (GSI). Semen was collected to evaluate spermatic density, cell membrane integrity and sperm motility. No difference (p > .05) was found on growth parameters, GSI, HSI and total protein. However, EC was lower in fish fed without ascorbic acid (the control group). Ascorbic acid supplementation provided positive effects on sperm characteristics. Fish from treatments with 53 and 107 mg/kg presented the best results for motility time (133.30 ± 4.25 and 135.00 ± 2.77 respectively). Treatments with 107, 216 and 708 mg/kg provided the best results for motility rate (92.0 ± 2.9%, 93.0 ± 5.8% and 93.0 ± 5.8% respectively). Supplementation with 107 and 216 mg/kg provided the best results for plasma membrane integrity (70.12 ± 9.10% and 76.3 ± 3.1% respectively). Lower spermatic density was observed in fish without ascorbic acid supplementation, although no difference was found in sperm density among the treatments with ascorbic acid (p < .05). Considering these results, supplementation of dietary ascorbic acid between 107 and 216 mg/kg optimizes the spermatic quality in males of lebranche mullet.  相似文献   
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Marine natural products have been the focus of discovery for new products of chemical and pharmacological interest. The aim of this study was to evaluate the antinociceptive activity of the methanolic (ME), acetate (AE), hexanic (HE) and chloroform (CE) extracts obtained from Caulerpa mexicana, and ME, CE and HE obtained from Caulerpa sertularioides. These marine algae are found all over the world, mainly in tropical regions. Models such as the writhing test, the hot plate test and formalin-induced nociception test were used to evaluate antinociceptive activity in laboratory mice. In the writhing test, all the extracts were administered orally at a concentration of 100 mg/kg, and induced high peripheral antinociceptive activity, with a reduction in the nociception induced by acetic acid above 65%. In the hot plate test, treatment with extracts from C. sertularioides (100 mg/kg, p.o.) did not significantly increase the latency of response, although the ME, AE and HE from C. mexicana showed activity in this model. This result suggests that these extracts exhibit antinociceptive activity. In the formalin test, it was observed that ME, AE and HE obtained from C. mexicana reduced the effects of formalin in both phases. On the other hand only CE from C. sertularioides induced significant inhibition of the nociceptive response in the first phase. To better assess the potential anti-inflammatory activity of the extracts, the carrageenan-induced peritonitis test was used to test Caulerpa spp. extracts on cell migration into the peritoneal cavity. In this assay, all extracts evaluated were able to significantly inhibit leukocyte migration into the peritoneal cavity in comparison with carrageenan. These data demonstrate that extracts from Caulerpa species elicit pronounced antinociceptive and anti-inflamatory activity against several nociception models. However, pharmacological and chemical studies are continuing in order to characterize the mechanism(s) responsible for the antinociceptive action and also to identify the active principles present in the Caulerpa species.  相似文献   
6.
Since 1989, tomato plants showing symptoms of stolbur disease have been sporadically noticed at the ‘Stuard Experimental Farm for Agriculture’in the Province of Parma, Emilia‐Romagna region (north Italy). In this farm, one of the largest in Italy for tomato plantation, more than 36 commercial tomato lines have been comparatively evaluated for suitability for processing into diced or crushed tomato products. Recently, among these lines, some plants of two hybrids (Perfect Peel, TI 991) showed the typical symptoms of ‘stolbur’infection (yellowing and reduction of leaves, sterility or fruit alterations, stunting of the plants). In order to protect these plants, as Perfect Peel is one of the most important commercial hybrids, transmission electron microscopy was used to identify the pathogens responsible for the disease and to study the alterations caused in cells. Phytoplasmas were observed in the phloem cells of leaf and stem tissues of the two tomato hybrids and also in Catharanthus roseus used as test plant. This is the first report of identification, by electron microscopy, of stolbur phytoplasma affecting economically important tomato crops in Emilia‐Romagna region.  相似文献   
7.
Hoof care, lesion curettage, and application of 5 % Stryphnodendron adstringens bark extract (S. adstringens (Mart.) Coville) or 3 % copper sulfate on surgical wounds of cattle were carried out in this research. A total of 180 cattle with digital dermatitis were used. They were distributed into six groups of 30 animals each (GI, GII, GIII, GIV, GV, and GVI). In GI and GII, only the sick digit was trimmed; in GIII and GIV, both sick and healthy digits of the lesioned limb were trimmed; and in GV and GVI, all digits were trimmed. During the postoperative period, 5 % S. adstringens extract was applied in GI, GIII, and GV, and 3 % copper sulfate solution was applied in GII, GIV, and GVI. After 60 days of evaluation, the data were analyzed using the Chi-squared test (p?≤?0.05). Both therapeutic protocols utilizing surgical curettage of the lesions were efficient for treating digital dermatitis. However, when the procedure is followed by the trimming of sick and healthy digits, the healing is optimized and a greater number of animals are rehabilitated.  相似文献   
8.
The marine environment is an extraordinary reservoir of bioactive natural products, many of which exhibit chemical and structural features not found in terrestrial natural products. In this regard, the aim of this study was to investigate the possible antinociceptive and anti-inflammatory activities of a crude methanolic extract of the red alga Bryothamnion triquetrum (BT-MeOH) in murine models. Groups of Swiss mice of both sexes (25–30 g) were used throughout the experiments. The potential antinociceptive of BT-MeOH was evaluated by means of the following tests: acetic acid-induced writhing, hot-plate test and glutamate- and formalin-induced nociception. The anti-inflammatory activity of BT-MeOH was investigated using the zymosan A-induced peritonitis test. The tests were conducted using 100 mg/kg (p.o.) BT-MeOH, 33.3 mg/kg (p.o.) dipyrone, 35.7 mg/kg (p.o.) indomethacin and 5.7 mg/kg (s.c.) morphine. The extract and all standard drugs were administered 40 min before the nociceptive/inflammatory stimulus. In the acetic acid-induced writhing test, BT-MeOH and dipyrone inhibited the nociceptive response by 55.9% (22.2 ± 2.0 writhings; p < 0.01) and 80.9% (9.6 ± 2.1 writhings; p < 0.01). In the hot-plate test, BT-MeOH did not increase the latency time of the animals in the time evaluated. In addition, BT-MeOH inhibited glutamate-induced nociception by 50.1%. While BT-MeOH did not inhibit the neurogenic phase in formalin-induced nociception, the inflammatory phase was inhibited by 53.1% (66.8 ± 14.2 s; p < 0.01). Indomethacin inhibited the inflammatory phase by 60.2% (56.8 ± 8.7 s; p < 0.01). In the zymosan-induced peritonitis test, BT-MeOH inhibited 55.6% (6.6 ± 0.2 × 106 leukocytes/mL; p < 0.01) of leukocyte migration, while indomethacin inhibited 78.1% (3.2 ± 0.1 × 106 leukocytes/mL; p < 0.01). Based on the results obtained in this study, we conclude that BT-MeOH has peripheral antinociceptive and anti-inflammatory activities. However, more studies need to be conducted to confirm these properties.  相似文献   
9.
Hypothetically, humic substances (HSs) can improve the response of plants in sandy soils. The objective was to assess the effect of applying an organomineral fertilizer enriched with HSs on soybean plants grown with and without water stress. The experimental design was entirely randomized, in a greenhouse, in a 2 × 5 factorial setup (two moisture levels and five fertilizer doses: 0, 1, 2, 4, and 8 mL dm?3), for a total of 10 treatments, with eight repetitions, using as substrate a Psamment. The organomineral fertilizer was applied in the soil 21 days after plant emergence, and the water regimes were established 1 week thereafter. Plant height, shoot and root dry mass, mineral nutrition, and grain yield were evaluated. There was a positive response to the doses, with the most efficient one under water stress being 6.5 mL dm?3 and HSs favored the uptake of micronutrients.  相似文献   
10.
Villa  S.  Finizio  A.  Diaz Diaz  R.  Vighi  M. 《Water, air, and soil pollution》2003,146(1-4):335-349
The distribution of persistent organochlorine pesticides (HCB, HCH, DDT and its metabolites) was studied by analyzing pine needles in the oceanic island of Tenerife (Canary Islands, Spain). Tenerife is a subtropical oceanic island, characterized by the presence of a high mountain (Pico de Teide, 3,718 m a.s.l.) and by a peculiar climatic condition. The southern side is warm and sometimes during the year influenced by dry winds coming from Africa, while the northern side is cool and wet, with an almost persistent cloudiness (called `mar de nubes'), due to winds coming from the northern Atlantic. Furthermore a developed agricultural area is present at sea level. Pine needle samples were collected on both sides of the island, from the sea level up to the upper level of pine distribution (2,100 m a.s.l.). The distribution patterns of organochlorine pesticides seem to be affected mainly by local emissions. Up to the considered altitude layer, the influence of global circulation of persistent organic pollutants seems to play a negligible role. The behavior of chemicals is consistent with their physical-chemical properties, with some influence due to climatic conditions.  相似文献   
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