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131.
The aim of our study was to evaluate the parasite — host interactions at apoptosis level. We studied histopathological changes and time course of apoptosis in the duodenum during Eimeria acervulina infection. One-day-old broiler chicks were randomly allocated into two equal groups. At the age of two weeks the first group was experimentally infected with a pure suspension of sporulated E. acervulina oocysts. The second group served as a negative control. Tissue samples from the upper part of duodenum were obtained at 0.5, 1, 2, 3, 4, 5 and 6 days post infection. Biopsies of duodenum were studied immunohistochemically using DeadEnd™ Colometric TUNEL System for apoptosis detection in duodenal mucosa. Number of parasites in duodenal epithelium was also investigated. Our experimental results demonstrate: (i) macroscopic and histopathological changes in epithelium detected mainly in proximal segment of duodenum in infected groups; (ii) the number of developmental stages of E. acervulina (DSEA) during our trial increased, reaching the maximum 5 days post infection (dpi) (332.2 ± 16.12) (mean ± SEM), whereas the amount of DSEA declined significantly as late as 6 dpi (124.6 ± 3.91); (iii) the highest apoptosis level was recorded in initiatory 0.5 dpi (13.2 ± 1.02) and on the end of parasite development cycle after 5 dpi (12.6 ± 1.36). Finally, results showed that there was a period of inhibition of apoptosis during infection by E. acervulina.  相似文献   
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The horse-bearded mussel Modiolus barbatus (Linneus, 1758) is an important edible bivalve in the Adriatic Sea; its population is especially large in the Mali Ston Bay area, where the species is present at depths up to 8 m. In order to assess the sustainable exploitation rate for this species, as well as to estimate its potential capacity for a sustainable aquaculture production, we determined the species’ reproductive cycle along with its nutrient storage strategy, employing histological and biochemical methods. The population shows significantly more females than males, and no hermaphrodites. The smallest adult individual, an active male, was 16.0 mm in length, suggesting that sexual maturation starts around this length. While the period between January and February is characterized by sexual repose, early and late stages of gametogenesis were found between March and May, and spawning peaked from June till August. The increase of oocyte diameter followed the same trend. A significant positive correlation was observed between gonad index and temperature, and a negative correlation between gonad index and salinity. Oscillations of stored nutrients were tightly coupled with the gametogenic cycle.  相似文献   
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Molecular Diagnosis & Therapy - Human kinesin 14 (KIF14) is one of the 70 prognostic marker genes (so-called Amsterdam profile) previously identified by the microarray of breast carcinomas, and...  相似文献   
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Developmental dysphasia (DD) is a disorder resulting in a communication impairment. Children diagnosed with this condition are usually referred to a speech therapist. Further to conventional speech therapy it is possible to adopt a complementary animal-assisted approach. For the present study, we assembled a cohort comprising 69 children diagnosed with DD. The children in the experimental group (n = 31; 21 male, 10 female) ranged from 4 to 7 years (M = 5.53 years, SD = 0.81 years). The control group was comprised of children (n = 38; 31 male, 7 female) aged from 4 to 6 years (M = 4.85 years, SD = 0.51 years). While the latter received traditional speech therapy, the experimental group experienced sessions enhanced by animal-assistance therapy (AAT) with a dog present for co-therapy purposes. As primary outcome measures, the Kwint-Stambak (KS) test was adopted (for assessing facial motricity), together with the Bruininks-Oseretsky (BO) test (for evaluating motor proficiency). Both of these revealed statistically significant improvement in some primary outcome measures for the experimental group over the control group. Regarding narrowing and shutting of the eyes, as well as filling up the cheeks with air and smiling (as measured by the KS test), the experimental group did significantly better than the control group. The inclusion of dogs in such therapy increased the chances of success in certain abilities, when assessed by the KS and BO tests (odds ratios for success: 1.6 and 2.0, respectively), compared with the control group. Canine-assisted speech therapy may be a valuable tool for enhancing the effect of speech therapy on children with DD, and we speculate that the reason for this relates to the nature of communication between children and companion animals.  相似文献   
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Recognition of the 3′-splice site is a key step in pre-mRNA splicing and accomplished by a dynamic complex comprising splicing factor 1 (SF1) and the U2 snRNP auxiliary factor 65-kDa subunit (U2AF65). Both proteins mediate protein–protein and protein–RNA interactions for cooperative RNA-binding during spliceosome assembly. Here, we report the solution structure of a novel helix-hairpin domain in the N-terminal region of SF1 (SF1NTD). The nuclear magnetic resonance- and small-angle X-ray scattering-derived structure of a complex of the SF1NTD with the C-terminal U2AF homology motif domain of U2AF65 (U2AF65UHM) reveals that, in addition to the known U2AF65UHM–SF1 interaction, the helix-hairpin domain forms a secondary, hydrophobic interface with U2AF65UHM, which locks the orientation of the two subunits. Mutational analysis shows that the helix hairpin is essential for cooperative formation of the ternary SF1–U2AF65–RNA complex. We further show that tandem serine phosphorylation of a conserved Ser80-Pro81-Ser82-Pro83 motif rigidifies a long unstructured linker in the SF1 helix hairpin. Phosphorylation does not significantly alter the overall conformations of SF1, SF1–U2AF65 or the SF1–U2AF65–RNA complexes, but slightly enhances RNA binding. Our results indicate that the helix-hairpin domain of SF1 is required for cooperative 3′-splice site recognition presumably by stabilizing a unique quaternary arrangement of the SF1–U2AF65–RNA complex.  相似文献   
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