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41.
The juçara fruits (Euterpe edulis Martius), native to the Atlantic Forest, are rich in anthocyanins. To preserve the anthocyanins in juçara fruit pulp, this study aimed to evaluate the effectiveness of microencapsulation by spray drying and freeze drying with maltodextrin (dextrose equivalent 16.5 to 19.5) and gum arabic in different proportions. The obtained microparticles were characterized by quantifying the total polyphenol and anthocyanin contents, by performing differential scanning calorimetry, thermogravimetry, and infrared spectroscopy and by using scanning electron microscopy to analyze the morphology of the particles. The total amount of polyphenols in the fruit pulp was 750?±?16.7 mg GAE/100 g of the freeze-dried sample. The total anthocyanins in the fruit pulp was 181.25?±?5.36 (mg/100 g). The microparticles were formed by employing maltodextrin and gum arabic in a 1:1 proportion as the polymeric matrix; the mixtures of pulp and polymeric matrix were prepared in proportions of 2:3 and 2:1, preserving up to 83.69% of the anthocyanin content. Lyophilization of the 2:1 mixture resulted in an anthocyanin content of 116.89?±?4.43 (mg/100 g), whereas lyophilization of the 2:3 mixture resulted in 151.68?±?1.39 (mg/100 g) anthocyanin content, which did not differ from the value obtained by spray drying the 2:3 mixture (150.76?±?5.79 (mg/100 g)). Thermal analyses showed that the microparticles obtained by freeze drying at a ratio of 2:3 presented greater resistance to degradation with increasing temperature. The incorporation of the pulp in the polymeric matrix was demonstrated by IR analyses. Microparticles obtained by freeze drying showed the formation of various-sized flakes, whereas those obtained by spray drying were spherical in shape. Microencapsulation is a possible alternative for improving the stability of the anthocyanins in this fruit.  相似文献   
42.
Nitric oxide (NO) is a free radical gas with important roles in the host's immune response against viral infections. In this study, we examined the kinetics and distribution of nitric oxide synthase (NOS) expression during the early steps of infection of the porcine nervous system by the alphaherpesvirus pseudorabies virus (PRV). To this end, we examined changes in the expression of the three major NOS isoforms, neuronal NOS (nNOS), endothelial NOS (eNOS) and inducible NOS (iNOS), by immunohistochemistry in the trigeminal ganglia and brain of pigs inoculated intranasally with a virulent PRV strain. The results obtained show that infection of the porcine nervous system by PRV induced a rapid and progressive increment in NOS expression that coincided in timing, location, and magnitude with those of virus propagation in the nervous tissue. A major finding of this study was that PRV caused not only nNOS and iNOS induction in a variety of cell types, but also eNOS up-regulation in endothelial cells and neurons; therefore, all possible sources of NO are activated and probably contribute to the overproduction of NO during infection with the neurotropic alphaherpesvirus PRV in its natural host.  相似文献   
43.
Tests were performed to evaluate the biochemical alterations in Rattus norvegicus after infection by the intestinal trematode Echinostoma paraensei. The rodents received 150 metacercariae each, serum samples were collected and the parasite load was quantified weekly until the fifth week of infection. The levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALKP), gamma-glutamyl transferase (GGT), bilirubin, glucose, total proteins and fractions and hepatic glycogen were determined. All the animals exposed to the metacercariae were infected in the first week and worms were recovered up to the third week after infection. The levels of AST, ALT, GGT, bilirubin and globulin rose in the first and/or second week and declined thereafter to levels near those of the control group. In contrast, the level of total proteins in the plasma fell significantly in the first week while the ALKP activity went down only in the fourth and fifth weeks in relation to the control group. There was no significant difference in the levels of albumin, glycogen and glucose. Infection by E. paraensei in R. norvegicus causes changes in the hepatic function, possibly resulting from the cholestasis produced by the partial obstruction of the bile duct by the helminths.  相似文献   
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45.
Cenourete® is a minimally processed carrot root similar to the American product known as ‘baby-carrot’. This product is obtained through peeling and abrasion of cylindrical carrot root segments. The cultivar Esplanada is well suited for the production of Cenourete® due to its characteristics of long length and cylindrical root shape as well as uniform dark orange root colour. For Cenourete® production, the root should be less than 25 mm in diameter. However, it is well known that root size is influenced by planting density and harvest time. Therefore, the adjustment of the cultural practices would be necessary to increase root yield aimed for Cenourete® processing. The recovery of Cenourete® from ‘Esplanada’ was studied under two between-line spacings: 20 cm (5 transversal lines/m) and 12.5 cm (8 transversal lines/m). Roots were harvested at 80, 90, 100 and 110 days after sowing. Cenourete® yield ranged from 2.39 ± 0.37 to 10.75 ± 1.07 t/ha depending on the combination of harvesting date and between-line spacing. These values corresponded, respectively, to a percent Cenourete® yield recovery of 3.3 ± 0.7%–28.6 ± 2.8% in relation to the total root production. It was concluded that higher yield is obtained with 12.5 cm between-line spacing than with 20 cm between-line spacing and with earlier harvest (80–90 days) than with late harvest (100–110 days).  相似文献   
46.
Enteromyxoses are relevant diseases for turbot and gilthead sea bream aquaculture. The myxozoan parasites invade the intestinal mucosa, causing a cachectic syndrome associated with intestinal barrier alteration; nonetheless, their pathological impact is different. Turbot infected by Enteromyxum scophthalmi develop more severe intestinal lesions, reaching mortality rates of 100%, whereas in E. leei-infected gilthead sea bream, the disease progresses slowly, and mortality rates are lower. The mechanisms underlying the different pathogenesis are still unclear. We studied the distribution and expression changes of E-cadherin, a highly conserved protein of the adherens junctions, in the intestine of both species by immunohistochemistry and quantitative PCR, using the same immunohistochemical protocol and common primers. The regular immunostaining pattern observed in control fish turned into markedly irregular in parasitized turbot, showing an intense immunoreaction at the host–parasite interface. Nevertheless, E-cadherin gene expression was not significantly modulated in this species. On the contrary, no evident changes in the protein distribution were noticed in gilthead sea bream, whereas a significant gene downregulation occurred in advanced infection. The results contribute to the understanding of the different host–parasite interactions in enteromyxoses. Host and parasite cells appear to establish diverse relationships in these species, which could underlie the different pathological picture.  相似文献   
47.
This study describes morphopathologic changes in naturally infected farmed Senegalese sole affected by tenacibaculosis caused by Tenacibaculum maritimum. Macroscopic observation, in addition to light microscopy and scanning electron microscopy, was used to study the lesions. Main lesions were characterized by complete loss of epidermis and dermis, as well as extensive necrosis of muscle layers. Mild-to-moderate inflammatory response with the presence of macrophages was noted around hyaline degenerated muscle cells. Gram-negative filamentous bacteria could be detected only at the dermis. Under scanning electron microscopy, filamentous bacteria located over the scales without epithelium could be observed. These findings together with the isolation and PCR detection of the bacteria in kidney and skin tissues suggest that once the bacteria reach the dermis, probably through eroded epidermis, they are able to proliferate and produce enzymes that are responsible for the damage in the underlying tissues.  相似文献   
48.
A sensitive and specific immunohistochemical technique was developed to improve the diagnosis of tenacibaculosis and to better understand its pathogenesis. Senegalese sole Solea senegalensis Kaup, 1858 were inoculated subcutaneously with a bacterial suspension of Tenacibaculum maritimum, and samples were taken at different hours post‐inoculation. Sections from different organs were used as positive controls. In addition, a total of 128 field samples from different organs collected from tenacibaculosis outbreaks were used. Tenacibaculum maritimum antigens were detected in several organs of experimentally infected Senegalese sole and in at least one of the tissues from fish suffering from natural tenacibaculosis previously confirmed by culture and PCR‐based methods. In fish collected during outbreaks, a strong positive reaction was detected in ulcerative skin areas. Moreover, bacterial antigen was identified inside scale pockets and in sites of the skin with mild lesion. In kidney and spleen, evident immunostaining of bacterial antigen was detected in both naturally and experimentally infected fish. Besides, the presence of T. maritimum in the intestinal tract without associated histological changes suggests that this organ may act as a reservoir for T. maritimum. The results of this study confirm the usefulness of IHC for the diagnosis of tenacibaculosis in paraffin‐embedded tissues.  相似文献   
49.
Use of biotechnology techniques combined with mutagenesis in Musa spp. allows genetic variability to be increased to improve important agronomic characters. Damage caused to Musa plantations by strong winds and tropical hurricanes makes it necessary to select clones with reduced height and better resistance to wind. The objective of this study is to develop mutant clones of FHIA-21 (Musa AAAB) with reduced height, a good agronomical trait. Multiple buds obtained by in vitro culture were subjected to gamma radiation from 60Co sources at dose of 25 Gy. Irradiated buds were multiplied, elongated, rooted, and then planted (10,000 plants) in the field. In the clonal study, 98 mutant clones with lower pseudostem height compared with the original cultivar were selected. Four mutants with reduced height at bunch emergency were selected (IBP 14-23, IBP 17-13, IBP 24-14, and IBP 47-4). Mutants IBP 24-14 and IBP 47-4 showed poor agronomical features, reduced foliar area, and resulted of no commercial value. The results indicated that mutant IBP 14-23 retains the character of resistance to black sigatoka from its parent FHIA-21, combined with important agronomical traits during the third culture cycle, making it a promising cultivar material, representing 0.01% selection efficiency. This is the first report of improvement for height reduction of the tetraploid hybrid FHIA-21 through physical mutagenesis.  相似文献   
50.
A study was conducted to investigate the potential of purified lignin and hemicellulose as prebiotics in diets for Atlantic salmon, Salmo salar L., postsmolt in seawater (30 ppt) at 14.9 ± 1.2°C. Triplicate groups of fish (initial individual body mass of 101.6 ± 1.2 g) were fed either the fishmeal-dense (32% of fishmeal) control diet (A) or one of the nine diets (15% fishmeal) supplemented with lignin:hemicellulose ratios (% diet:% diet) of 0.05:0 (B), 0.25:0 (C), 0.50:0 (D), 1.00:0 (E), 0:0.05 (F), 0:0.25 (G), 0:0.50 (H), 0.05:0.25 (I), and 0.25:0.50 (J) for 12 weeks in a complete randomized experimental design. At the end of the experiment, the thermal-unit growth coefficient (TGC) was significantly lower in salmon fed diets with 0.50% and 1.00% purified lignin than those fed the control diet, while there was no significant difference between the other treatments and the control diet (P < 0.05). The feed efficiency (FE) was significantly lower in salmon fed diets with 0.50% and 1.00% purified lignin and 0.05% hemicellulose than those fed the control diet, while there was no significant difference between the other treatments and the control diet (P < 0.05). The hepatosomatic index (HSI), intestinal villus length, and apparent digestibility coefficient (ADC) of nutrients in diets were similar (P > 0.05) among all the diets. This study demonstrated that inclusions of up to 0.25% of dietary purified lignin alone, and 0.25%–0.50% of dietary hemicellulose alone or in combination with dietary lignin can be considered as candidate prebiotics in Atlantic salmon nutrition.  相似文献   
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