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1.
Marcilene Fernandes Almeida dos Santos Cleber Furlanetto Maria Rita Alves Almeida Marina Dechechi Gomes Carneiro Fabiane Castro Mota Ana Cristina Meneses Mendes Gomes Natália Orrú Reis Silveira Joelma Gardênia Pereira Silva Philippe Castagnone-Sereno Myrian Silvana Tigano Regina Maria Dechechi Gomes Carneiro 《European journal of plant pathology / European Foundation for Plant Pathology》2012,134(4):671-684
Meloidogyne incognita is one of the most polyphagous species of root-knot nematodes occurring in Brazil and worldwide. Eight M. incognita isolates were studied, representing two enzymatic phenotypes (esterase and malate desydrogenase: I1/N1, I2/N1) and four cryptic Meloidogyne sp.1 (S2/N1) isolates, representing one cytological type (3n?=?40–46). Three M. hispanica isolates (Hi3/N1, 2n?=?32–36) and two of an atypical Meloidogyne sp.2 (S2a/N3, 3n?=?40–44) were included in this study for comparison. All isolates were tested with three M. incognita-specific molecular markers. The primer pairs B06F/R, miF/R and incK14F/R amplified three species-specific fragments of 1,200?bp, 955?bp and 399?bp, respectively for M. incognita and Meloidogyne sp.1 isolates. No amplification occurred in the M. hispanica and Meloidogyne sp.2 isolates, except with primers miF/R (1,650?bp). The genetic variability of the Meloidogyne spp. isolates was evaluated, using RAPD and ISSR markers. The phylogenetic analyses revealed two strongly supported monophyletic clades: clade I, consisting of M. hispanica and the atypical Meloidogyne sp.2 isolates, and clade II, clustering together all M. incognita and the Meloidogyne sp.1 isolates. Considering the biometrical, cytological and molecular approaches, it was possible to conclude that the isolates with three enzymatic phenotypes (I1/N1, I2/N1 and S2/N1) presented the characteristics described for M. incognita. Some correlations were detected between the isozymatic phenotypes and the tree topology (S2a/N3, Hi3/N1, I1/N1, S2/N1), but no strict correlation could be observed for the phenotype I2/N1 and one isolate of S2/N1. Morphologically, the Msp.2 isolates differ from M. incognita and M. hispanica by the female stylet features presenting straight cone tip and round pear shaped knobs, posteriorly sloping. The results of this study suggested that the Msp.2 isolates with phenotypes S2aN3 belong to a new or an unidentified species closely related to M. hispanica. 相似文献
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The isolation of (+)-uleine (1) and (+)-demethoxyaspidospermine (2) from the bark of Plumeria lancifolia is reported along with (1)H- and (13)C-NMR data. 相似文献
4.
Aerobic stability of sugar-cane silage inoculated with tropical strains of lactic acid bacteria 下载免费PDF全文
B. F. Carvalho C. L. S. Ávila M. G. C. P. Miguel J. C. Pinto M. C. Santos R. F. Schwan 《Grass and Forage Science》2015,70(2):308-323
Aerobic stability is an important feature in the evaluation of silages. The aims were to investigate the chemical and microbiological changes that occur in sugar-cane (Saccharum spp.) silage after aerobic exposure, to identify the major species of yeasts associated with the aerobic deterioration process and to select lactic acid bacteria (LAB) strains that can improve the aerobic stability of this silage. Fourteen wild LAB strains belonging to Lactobacillus plantarum, L. brevis and L. hilgardii were evaluated using experimental silos. Silage samples were collected at 0, 96 and 216 h after aerobic exposure to determinate the DM, WSC, pH, products of fermentation, to evaluate the silage temperatures and to identify yeast species associated with the aerobic deterioration of silage. The strains tested were able to modify the fermentative and chemical parameters and the diversity of yeasts species of silage after aerobic exposure. There was no association between the facultative or obligatory heterofermentative fermentation patterns and the increased aerobic stability of silage. Aerobic stability of sugar-cane silages was associated with high acetic acid and 1,2-propanediol concentrations. L. hilgardii UFLA SIL51 and UFLA SIL52 strains promoted an increase in aerobic stability of silage. 相似文献
5.
Pigatto JA Andrade MC Laus JL Santos JM Brooks DE Guedes PM Barros PS 《Veterinary ophthalmology》2004,7(3):205-208
The objective of this study was to examine the endothelial surface morphology and to perform morphometric analysis of the corneal endothelial cells of Yacare caiman (Caiman yacare) using scanning electron microscopy. Morphometric analysis with regard to polygonality, mean cell area, cell density and coefficient of variation of mean cell area was performed. Cell areas were measured using image analysis software. The normal corneal endothelium of Yacare caiman consisted of polygonal cells of uniform size and shape with interdigitations of the cell borders. Microvilli appeared as protrusions on the cellular surface. The average cell area was 270 +/- 24 microm(2) and the endothelial cell density was 3704 +/- 324 cells/mm(2). The coefficient of variation of cell area was 0.22. This study demonstrates that the Yacare caiman corneal endothelium is similar to those described in other vertebrates. 相似文献
6.
Kuehn CC Oliveira LG Santos CD Augusto MB Toldo MP do Prado JC 《Veterinary parasitology》2011,177(3-4):242-246
DHEA, a steroid hormone synthesized from cholesterol by cells of the adrenal cortex, plays an essential role in enhancing the host's resistance to different experimental infections. Receptors for this hormone can be found in distinct immune cells (especially macrophages) that are known to be the first line defense against Trypanosoma cruzi infection. These cells operate through an indirect pathway releasing nitric oxide (NO) and cytokines such TNF-α and IL-12 which in turn trigger an enhancement of natural killer cells and lymphocytes which finally secrete pro and anti-inflammatory cytokines. The effects of pre- and post-infection DHEA treatment on production of IL-12, TNFα and NO were evaluated. T. cruzi infected macrophages post treated with DHEA displayed enhanced concentrations of TNF-α, IL-12 and NO. Probably, the mechanisms that induced the production of cytokines by infected cells are more efficient when the immune system has been stimulated first by parasite invasion, suggesting that the protective role of DHEA is greater when administered post infection. 相似文献
7.
F. Miró R. Santos J. L. Garrido-Castro A. M. Galisteo R. Medina-Carnicer 《Veterinary research communications》2009,33(6):507-513
The handled trot of three Lusitano Purebred stallions was analyzed by using 2D and 3D kinematical analysis methods. Using
the same capture and analysis system, 2D and 3D data of some linear (stride length, maximal height of the hoof trajectories)
and angular (angular range of motion, inclination of bone segments) variables were obtained. A paired Student T-test was performed
in order to detect statistically significant differences between data resulting from the two methodologies With respect to
the angular variables, there were significant differences in scapula inclination, shoulder angle, cannon inclination and protraction-retraction
angle in the forelimb variables, but none of them were statistically different in the hind limb. Differences between the two
methods were found in most of the linear variables analyzed. 相似文献
8.
GROSS AND HISTOPATHOLOGIC CORRELATION OF LOW‐FIELD MAGNETIC RESONANCE IMAGING FINDINGS IN THE STIFLE OF ASYMPTOMATIC HORSES 下载免费PDF全文
Marcos P. Santos Santiago D. Gutierrez‐Nibeyro Alexia L. McKnight Kuldeep Singh 《Veterinary radiology & ultrasound》2015,56(4):407-416
With the recent introduction of a 0.25T rotating MRI system, clinical evaluation of the equine stifle joint is now possible in the average equine athlete. A recent publication described common abnormalities of horses with stifle lameness detected with a low‐field MRI system; however, postmortem corroboration of the lesions detected was not possible. Therefore, our objective was to compare postmortem findings with low‐field MRI findings in equine cadaver stifle joints. Ten fresh cadaver stifle joints from horses without clinical signs of stifle disease were evaluated using low‐field MRI, gross dissection, and histopathology. In eight stifles, either the lateral or medial cranial meniscotibial ligament had an irregular shape, fiber separation, or moderate abnormal signal intensity (SI) on all sequences. In five stifles, the medial femoral condyle had articular cartilage fibrillation with or without an osteochondral defect over the weight bearing surface of the medial femoral condyle. All stifles had abnormal SI on all sequences within the patellar ligaments that corresponded with adipose tissue infiltrating between the collagen bundles. Other abnormalities identified included articular cartilage fibrillation of the tibial condyles in three stifles, and articular cartilage fibrillation with chondral defects in the patella in three stifles. All abnormalities detected with low‐field MRI were corroborated by gross dissection. Findings from the current study supported the use of low‐field MRI for detection of stifle joint lesions in horses and demonstrated that some stifle joint pathologies may be subclinical in horses. 相似文献
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10.
Gil de los Santos JR Storch OB Fernandes CG Gil-Turnes C 《Veterinary microbiology》2012,156(3-4):448-451
The probiotic properties of Pichia pastoris and of a recombinant P. pastoris containing the Clostridium perfringens alpha toxin gene were evaluated in broilers. One-day-old chicks randomly divided in four groups were fed with commercial feed devoid of antibacterials. The control group (1) received plain food, while the other groups were supplemented with either P. pastoris (2), the recombinant P. pastoris (3) or Bacillus cereus var. Toyoi (4). At day 49, live weights, feed efficiency and seroconversions were higher (P<0.05) in the supplemented groups than in the control groups. Group 3 showed the best results, while group 2 had lower weight gain than groups 3 and 4 although food conversion was better than in group 4. Seroconversions were not different (P>0.05) among the supplemented groups. Adverse reactions were not observed in histopathologic evaluation. We concluded that P. pastoris and the recombinant P. pastoris could be used as probiotics in broilers. 相似文献