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Euplotin C is a sesquiterpene of marine origin endowed with significant anti-microbial and anti-tumor properties. Despite the promising functional profile, its progress as a novel drug candidate has failed so far, due to its scarce solubility and poor stability in aqueous media, such as biological fluids. Therefore, overcoming these limits is an intriguing challenge for the scientific community. In this work, we synthesized β-cyclodextrin-based nanosponges and investigated their use as colloidal carriers for stably complex euplotin C. Results obtained proved the ability of the carrier to include the natural compound, showing remarkable values of both loading efficiency and capacity. Moreover, it also allowed us to preserve the chemical structure of the loaded compound, which was recovered unaltered once extracted from the complex. Therefore, the use of β-cyclodextrin-based nanosponges represents a viable option to vehiculate euplotin C, thus opening up its possible use as pharmacologically active compound.  相似文献   
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ObjectiveTo compare, in horses undergoing laparotomy for colic, the effects of administering or not administering a loading intravenous (IV) bolus of lidocaine prior to its constant rate infusion (CRI). Effects investigated during isoflurane anaesthesia were end-tidal isoflurane concentration (Fe’ISO), cardiovascular function, anaesthetic stability and the quality of recovery.Study designProspective, randomized clinical study.AnimalsThirty-six client-owned horses.MethodsHorses were assigned randomly to receive lidocaine as a CRI (50 μg kg−1 minute−1) either preceded (LB) or not preceded (L) by a loading dose (1.5 mg kg−1 IV over 15 minutes). Lidocaine infusion (LInf) was started (T0) within 20 minutes after induction of general anaesthesia and discontinued approximately 30 minutes before the end of surgery. Anaesthetic depth, Fe’ISO, intra-operative physiological parameters and quality of recovery were assessed or measured. Data were analysed using one-way anova, t-test, Fisher test, Wilcoxon and Kruskal–Wallis tests as appropriate (p < 0.05).ResultsMean ± SD Fe’ISO was 1.21 ± 0.08% in group LB and 1.23 ± 0.06% in group L. Heart rate was significantly higher in group L than in group LB at times T5-T15, T25, T35 and T95. No difference was found between groups in other measured physiological values, nor in any measure taken to improve these parameters. Recovery phase was comparable and satisfactory in all but one full term pregnant horse in group L which fractured a femur during recovery.ConclusionPreloading with a lidocaine bolus prior to a CRI of lidocaine did not influence isoflurane requirements, cardiopulmonary effects (other than a reduction in heart rate at some time points) or recovery compared to no preloading bolus.Clinical relevanceA loading dose of lidocaine prior to CRI does not confer any advantage in horses undergoing laparotomy for colic.  相似文献   
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Non-traditional vectors for paralytic shellfish poisoning   总被引:2,自引:0,他引:2       下载免费PDF全文
Paralytic shellfish poisoning (PSP), due to saxitoxin and related compounds, typically results from the consumption of filter-feeding molluscan shellfish that concentrate toxins from marine dinoflagellates. In addition to these microalgal sources, saxitoxin and related compounds, referred to in this review as STXs, are also produced in freshwater cyanobacteria and have been associated with calcareous red macroalgae. STXs are transferred and bioaccumulate throughout aquatic food webs, and can be vectored to terrestrial biota, including humans. Fisheries closures and human intoxications due to STXs have been documented in several non-traditional (i.e. non-filter-feeding) vectors. These include, but are not limited to, marine gastropods, both carnivorous and grazing, crustacea, and fish that acquire STXs through toxin transfer. Often due to spatial, temporal, or a species disconnection from the primary source of STXs (bloom forming dinoflagellates), monitoring and management of such non-traditional PSP vectors has been challenging. A brief literature review is provided for filter feeding (traditional) and non-filter feeding (non-traditional) vectors of STXs with specific reference to human effects. We include several case studies pertaining to management actions to prevent PSP, as well as food poisoning incidents from STX(s) accumulation in non-traditional PSP vectors.  相似文献   
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Landuse can alter soil organic carbon (SOC) fractions by affecting carbon inflows and outflows. This study evaluated changes in SOC fractions in response to different landuses under variable rainfalls. We compared cropland, grassland and forest soils in high rainfall (Islamabad ~1142 mm) and low rainfall (Chakwal ~667 mm) areas of Pothwar dryland, Pakistan. Forest soils in both rainfall areas had highest SOC (11.32 g kg?1), particulate organic carbon (POC, 1.70 g kg?1), mineral-associated organic carbon (MOC, 7.17 g kg?1) and aggregate-associated organic carbon (AOC, 7.86 g kg?1). However, in rangeland and cropland soils, these varied with rainfall. Under high rainfall, SOC and MOC were 12% and 17% higher in rangeland than in cropland while POC and AOC were equal. Under low rainfall, SOC and MOC were higher in rangeland than in cropland by 7.21 and 1.79 g kg?1 at 0–15 cm and equal at 15–30 cm depth. POC and AOC were higher in rangeland than in cropland, in both depths. Averagely, SOC, POC, MOC and AOC were 26%, 68%, 76% and 30% higher in high rainfall than in low rainfall soils. Sensitivity of SOC fractions to landuses observed under different rainfalls could provide useful information for soil management in subtropical drylands.  相似文献   
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Thymoma is a relatively common tumor in rabbits. Treatment with surgery, radiation therapy, and chemotherapy alone or in combination has been reported with varying outcomes. Stereotactic volumetric modulated arc radiotherapy delivered in a hypofractionated manner allows high doses of radiation to be delivered to the target volume while allowing sparing of adjacent critical structures. This therapy is ideally suited for thymomas in rabbits given their size, the difficulty of multiple anesthesia episodes and the complexity of the radiotherapy plans required due to the tumor's proximity to the heart, lungs, and mediastinal structures. Fifteen rabbits with thymoma were prospectively recruited for this observational, single institution, single arm clinical study. All rabbits were imaged with both computed tomography (CT) and magnetic resonance imaging (MRI). A total dose of 40 Gy in six fractions was delivered using a single arc over an 11‐day period with repeat CT simulation done every other fraction for adaptive planning. Follow‐up evaluation was done through repeat CT and MRI imaging and revealed complete responses using the Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Two rabbits had died at 618 and 718 days, 10 were alive and three were lost to follow‐up. Observed acute and late effects were graded according to the Veterinary Radiation Therapy Oncology Group (VRTOG) criteria and were found to be minimal.  相似文献   
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Aquaponics is emerging as an alternative for high-health food production. Being able to identify the technical viability of non-conventional plants and fish species would help to increase the interest and possibilities in aquaponic systems. The goal of the present study was to evaluate the aquaponics production of two garnish species: scallion (S) and parsley (P), using effluents of pacu and red tilapia culture. Two aquaponics devices were used, differing according to the fish species, generating two different effluents. Thus, for plant performance, four treatments were evaluated in a factorial design (plant species and fish effluent as main factors), as followed: Pacu-S, Tilapia-S, Pacu-P, and Tilapia-P, with three replicates each, for 35 days. Fish performance was evaluated using Student’s t test. Each experimental device included a fish tank, filters, and six experimental units for the plants (floating rafts). Results indicated that feed conversion ratio (FCR) was higher in tilapia as compared to pacu (p < 0.05); however, fish productivity and survival were similar between species. Plant performance parameters were similar with no significant differences regardless of the fish effluent (p > 0.05), except for higher number of leaves per plant in scallion cultured using pacu effluent. Plant performance comparing both plant species indicated that scallion performed better as compared to parsley in all parameters. In addition, scallion also performed better related to the plant quality index. The results indicate that pacu presented a viable alternative for the aquaponics production, and regarding to the garnish, scallion performed better results as compared to parsley.  相似文献   
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