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31.
Taking into account the role played by the neuroendocrine network in affecting the early development of the immune response, the present study aims to assess neonatal immunity in piglets by testing peripheral lymphocyte age-related changes in relationship to plasma levels of some relevant immunoregulatory hormones, such as growth hormone (GH), prolactin (PRL) and cortisol. For this purpose, we studied the peripheral lymphocyte age-related changes in relationship to plasma levels of GH, PRL and cortisol in conventional piglets from birth (day 0) to 41 days of age. A significant decrease was observed in the total number of lymphocytes at day 0, with a subsequent constant increment up to 41 days of age. Concomitantly, the number of T cell subsets (mainly CD8(+) cells and double positive CD4(+)CD8(+)) was low at birth, with strong increments between the 19th and 41st days of life. The CD4(+) T cell number subset was less diminished at birth than that of CD8(+), albeit with significant increments in the post-weaning period. Of interest, gammadelta T cells, which are more involved in innate immune efficiency, displayed the same trend as CD8(+) T cells from birth to the 41st day of life. From day 0 up to the 19th day, significant inverse correlations were found between T cell subsets and GH or PRL or cortisol, albeit with more significant inverse correlations with cortisol. The high levels of GH and PRL in the pre-weaning period may be due to the fact that they have to counteract the cortisol-mediated negative effect on lymphocyte production and development. These findings suggest that stress condition occurs at birth with decreases in the immune parameters, in the same way as in human newborns, with a subsequent gradual normalisation and immune development, as shown by decreased cortisol, GH and PRL normalisation and concomitant increments in T cell subsets.  相似文献   
32.
High-fidelity human patient simulators have been used for decades in medical education to provide opportunities for students to practice technical skills, diagnostic and therapeutic planning, and communication skills in a safe environment. A high-fidelity canine patient simulator (CPS) was developed using components from a human patient simulator and a low-fidelity foam core canine mannequin. Ninety-six veterinary students participated in cardiopulmonary arrest scenarios in groups of three to five students. Afterwards, participants were asked to complete an anonymous online survey describing their experiences. A total of 70 students (73%) completed the survey. All of the students (100%) felt that the simulator session expanded their cardiopulmonary resuscitation (CPR) knowledge base, and 97% responded that their skills and abilities had improved. Students also expressed positive opinions about the CPS, with 89% agreeing or strongly agreeing that the CPS was realistic and 73% agreeing or strongly agreeing that the scenarios generated emotions similar to real clinical situations. Most participants (98.5%) agreed or strongly agreed that the simulator was an engaging learning experience. Students commonly commented that the simulations allowed them to practice communication and teamwork skills and were more effective than paper-based, problem-oriented learning opportunities and lecture. Students also commented that they wanted more opportunities to participate in simulation exercises. These results suggest that high-fidelity veterinary simulation is an engaging educational methodology that addresses some limitations of other forms of problem-based learning. More studies are needed to quantitatively determine the effectiveness of this novel veterinary educational technology in comparison with more traditional approaches.  相似文献   
33.
Canine Malassezia dermatitis is frequently treated with systemic ketoconazole (KTZ) and itraconazole (ITZ). However, no information is available on the antifungal susceptibility to azoles and allilamine of Malassezia pachydermatis isolates from dogs with or without skin lesions. The present study was designed to evaluate the in vitro antifungal susceptibility of M. pachydermatis strains from dogs with or without skin lesions to KTZ, ITZ, miconazole (MICO), fluconazole (FLZ), posaconazole (POS), voriconazole (VOR) and terbinafine (TER) using the Clinical and Laboratory Standards Institute reference Broth Microdilution Method (CLSI M27-A2). The association between the susceptibility to antifungal compounds and the origin of M. pachydermatis, from skin with or without lesions has been also assessed. A total of 62 M. pachydermatis strains from healthy dogs (i.e., Group A=30) or with skin lesions (i.e., Group B=32) were tested. ITZ, KTZ and POS showed the highest activity against M. pachydermatis strains, whereas MICO TER and FLZ the lowest. A higher number of Malassezia resistant strains were registered among isolates from Group B than those from Group A. This study indicates that M. pachydermatis strains were susceptible to ITZ, KTZ, and POS. However, dogs with lesions may harbour strains with low susceptibility to antifungal agents and displaying cross-resistance phenomena to azole. The antifungal therapy in Malassezia infections requires careful appraisal of choice of drugs especially in cases of unresponsiveness to antifungal treatment or recurrent infections.  相似文献   
34.
An in-depth study of the secondary metabolites contained in the Caribbean sponge Smenospongia aurea led to the isolation of smenamide A (1) and B (2), hybrid peptide/polyketide compounds containing a dolapyrrolidinone unit. Their structures were elucidated using high-resolution ESI-MS/MS and homo- and heteronuclear 2D NMR experiments. Structures of smenamides suggested that they are products of the cyanobacterial metabolism, and 16S rRNA metagenomic analysis detected Synechococcus spongiarum as the only cyanobacterium present in S. aurea. Smenamides showed potent cytotoxic activity at nanomolar levels on lung cancer Calu-1 cells, which for compound 1 is exerted through a clear pro-apoptotic mechanism. This makes smenamides promising leads for antitumor drug design.  相似文献   
35.
Banana has been currently indicated as a good source of fructooligosaccharides (FOS), which are considered to be functional components of foods. However, significant differences in their amounts in bananas have been observed in the literature. This work aims to identify and quantify FOS during ripening in different banana cultivars belonging to the most common genomic groups cultivated in Brazil. Considering that these differences can be due to cultivar, stage of ripening, and the methodologies used for FOS analyses, sugar contents were analyzed by high performance anion exchange chromatography-pulsed amperometric detection (HPAEC-PAD) and gas chromatography-mass spectrometry (GC-MS). An initial screening of eight cultivars (Ouro, Nanic?o, Prata, Ma??, Mysore, Pacovan, Terra, and Figo) in a full-ripe stage showed that 1-kestose, the first member of the FOS series (amounts between 297 and 1600 microg/g of DM), was accumulated in all of them. Nystose, the second member, was detected only in Prata cultivar. Five of the cultivars were analyzed during ripening, and a strong correlation could be established with a specific sucrose level ( approximately 200 mg/g of DM), which seems to trigger the synthesis of 1-kestose (the low amounts of FOS, below the functional recommended dose, indicates that banana cannot be considered a good source of FOS).  相似文献   
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37.
The effect of transportation on peripheral blood lymphocyte subsets in 24 calves was investigated by flow cytometry. Blood was collected before departure, on arrival, at 24h and 1 week after arrival. Highest leucocyte and neutrophil counts, associated with increased concentrations of cortisol and catecholamines, indicated that stress was maximal upon arrival. At this time, a decrease in the percentages of all T lymphocyte subsets was evident, while they did not decrease as absolute counts. The proportion of CD21(+) cells did not change, indicating that the relative reduction of T lymphocyte subsets was not related to an increase in B lymphocytes. These variations may be due to the increase of a natural killer (NK) cell subset. NK cell expansion, together with increasing lymphocyte count and increasing major histocompatibility complex class II expression, may indicate stress-induced stimulation of the immune system.  相似文献   
38.
Tropical Animal Health and Production - Twenty-seven Nellore cow-calf pairs were submitted for feed efficiency testing. The animals were weighed every 21 ± 5 days to...  相似文献   
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40.
This study evaluated a vaccine made from crude rhoptry proteins of Toxoplasma gondii with Quil-A, which was administered to cats by the intranasal route. Eleven short-hair domestic cats were divided into four groups: G1 (n=3) received three doses (200 microg/dose) of the rhoptry vaccine with Quil-A (20 microg); G2 (n=3) received PBS with Quil-A (20 microg); G3 (n=3) and G4 (n=2) received only PBS. Treatments were administered at days 0, 21, and 42 by the intranasal route. Challenge was done to G1, G2, and G3 animals with 600 cysts of the VEG strain on day 51 (challenge day); G4 animals were unchallenged. The anti-T. gondii IgG and IgA antibody levels from sera were measured by indirect enzyme-linked immunosorbent assay (ELISA). At challenge, two animals from G1 revealed antibody levels for both IgG and IgA; oocysts were not detected in feces of these two cats. There were no differences in hematological values between groups throughout the experiment (p>0.10). Preventable fractions were 67% in G1 and 0% in G2 and G3. Comparatively, G1 animals shed 89.3% and 90.8% less oocysts than G3 and G4, respectively. Two out of three cats were protected against T. gondii oocyst shedding when the rhoptry vaccine was administered by the intranasal route. This is the first study using crude rhoptry proteins as vaccine by the intranasal route in cats to evaluate protection against oocysts shedding.  相似文献   
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