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971.
A new route for the synthesis of fatty alcohol derivatives of hydroxytyrosol and other olive oil phenolic compounds was developed to allow the preparation of unsaturated derivatives. The biological activity of synthesized compounds was evaluated. Most of the compounds presented a significant antioxidant activity on low-density lipoprotein (LDL) particles. The activity of the tested products was significantly influenced by the number and position of unsaturations as well as modifications on the polar head of the synthesized compounds. Some of them presented modulation of food intake in rats and, due to their molecular similarity with CB(1) endogenous ligands, the endocannabinoid system and PPAR-α were also evaluated as potential targets. The pharmacodynamics could not be totally explained by CB(1) and PPAR-α receptor interactions because only two of the four compounds with biological activity showed a CB(1) activity and all of them presented low PPAR-α affinity, not justifying its whole in vivo activity. The hydroxytyrosol linoleylether (7) increased LDL resistance to oxidation with a capacity similar to that of hydroxytyrosol and was the most active in vivo compound with a hypophagic effect comparable to that of oleoylethanolamine. We consider that this compound could be a good lead compound for future drug development in obesity treatments.  相似文献   
972.
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974.
Methods such as real time (RT)-PCR have not been developed for the rapid detection and diagnosis of Dermatophilus (D.) congolensis infection. In the present study, a D. congolensis-specific SYBR Green RT-PCR assay was evaluated. The detection limit of the RT-PCR assay was 1 pg of DNA per PCR reaction. No cross-reaction with nucleic acids extracted from Pseudomonas aeruginosa, Mycobacterium tuberculosis, Staphylococcus aureus, or Austwickia chelonae was observed. Finally, the RT-PCR assay was used to evaluate clinical samples collected from naturally infected animals with D. congolensis. The results showed that this assay is a fast and reliable method for diagnosing dermatophilosis.  相似文献   
975.
A trial was conducted during the anestrous period in female goats to determine: (a) whether estrus can be induced in anestrous goats by administration of equine chorionic gonadotropic hormone (eCG) and PGF under pen conditions and (b) whether these sexually active female goats can elicit sexual arousal in sexually inactive bucks. One hundred and fifteen pluriparous, nonlactating mixed-breed female goats were randomly assigned to one of four treatment groups: (1) administration of a single dose of 240 IU of eCG, 50 μg PGF i.m., and 25 mg progesterone (P4) (eCG; n?=?30); (2) administration of P4 and exposure to female goats treated with eCG–PGF (P4; n?=?39); (3) administration of 0.5 ml saline and P4 (Sal; n?=?23); and (4) P4 plus exposure to female goats treated with saline (Con; n?=?23). After hormone administration, all goats were put together with adult sexually inactive bucks for 15 days. The percentage of goats in estrus during these 15 days was similar in eCG-treated animals and untreated animals exposed to the eCG animals (97 and 95 %). Pregnancy rate was also similar (63 vs. 64 %) between these two groups. eCG-treated goats exhibited estrus earlier (P?<?0.05) than the treated goats in contact with the eCG goats. Furthermore, eCG-treated goats had larger litters (1.9?±?0.2 vs. 1.6?±?0.1, P?<?0.05) than the untreated goats in contact with the eCG goats. These results show that fertile estrus can be induced in anestrous female goats by exposing them to female goats induced to estrus with eCG. This female–female interaction triggers the stimulation cycle leading to the sexual arousal of bucks.  相似文献   
976.
977.
The murine model has been widely used to study the host immune response to Neospora caninum. However, in most studies, the intraperitoneal route was preferentially used to establish infection. Here, C57BL/6 mice were infected with N. caninum tachyzoites by the intragastric route, as it more closely resembles the natural route of infection through the gastrointestinal tract. The elicited T-cell mediated immune response was evaluated in the intestinal epithelium and mesenteric lymph nodes (MLN). Early upon the parasitic challenge, IL-12 production by conventional and plasmacytoid dendritic cells was increased in MLN. Accordingly, increased proportions and numbers of TCRαβ+CD8+IFN-γ+ lymphocytes were detected, not only in the intestinal epithelium and MLN, but also in the spleen of the infected mice. In this organ, IFN-γ-producing TCRαβ+CD4+ T cells were also found to increase in the infected mice, however later than CD8+ T cells. Interestingly, splenic and MLN CD4+CD25+ T cells sorted from infected mice presented a suppressive activity on in vitro T cell proliferation and cytokine production above that of control counterparts. These results altogether indicate that, by producing IFN-γ, TCRαβ+CD8+ cells contribute for local and systemic host protection in the earliest days upon infection established through the gastrointestinal tract. Nevertheless, they also provide substantial evidence for a parasite-driven reinforcement of T regulatory cell function which may contribute for parasite persistence in the host and might represent an additional barrier to overcome towards effective vaccination.  相似文献   
978.
Bacterial cultures from 32 living and dead farmed white-tailed deer (Odocoileus virginianus) with necrobacillosis yielded Fusobacterium necrophorum from nine individuals, F. varium from six individuals, and Arcanobacterium pyogenes from 16 individuals. The isolates were characterized biochemically using automated identification systems. Gram-stained smears suggested the presence of Fusobacterium spp. in eight cases from which organisms were not cultured. Minimum inhibitory concentration determinations in 23 strains of gram-negative anaerobic bacteria detected resistance to enrofloxacin and clindamycin. Enrofloxacin resistance was detected in A. pyogenes isolates, and although biochemical profiling indicated that the deer strains of A. pyogenes could be grouped, it is uncertain whether these biochemical characteristics correlate with antigenic or virulence factors. Deer-specific or autogenous vaccines may provide a useful alternative to generic vaccines.  相似文献   
979.
Tropical Animal Health and Production - Heritable abnormalities can cause a reduction in productive performance, structural defects, or death of the animal. There are reports of hereditary...  相似文献   
980.

This study was conducted to determine the best combination between two collection method and two extenders in the cryopreservation of semen from creole bulls adapted to highlands of the Ecuadorian Andes. Sixty ejaculates from three adult Creole bulls were evaluated after collection by artificial vagina (AV) and electroejaculation (EE). Semen samples were split into two aliquots and diluted with a soy lecithin extender (Andromed®; A) or an egg yolk-containing extender (Triladyl®; T) and packed in straws of 0.25 ml with 20 × 106 sperms. Optical microscopy and computer-assisted semen analysis system (CASA) were used to evaluate semen quality characteristics. The effects of collection methods and extender type as well as its interaction were evaluated by a factorial ANOVA and Bonferroni’s test. Semen samples collected with EE and frozen with T (EE-T) and A (EE-A) had greater proportion of spermatozoa with optical assessed individual progressive motility (IPM), plasmatic membrane intact (HosT), and lower tail abnormalities than those obtained with AV and frozen with the same extenders (AV-T and AV-A); however, differences were significant only between EE-A and AV-T. CASA assessment indicated that the total mobility (TM) was greater (P < 0.05) in semen samples diluted with T, although these samples had a greater proportion (P < 0.05) of sperms with local motility (LM) and fewer immobile sperms (IS), than those extended with A. Generally, semen samples obtained with EE or AV and diluted with T seems to be the best option to ciopreserve gametes of Creole bulls raised in highlands of Ecuadorian Andes.

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