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31.
The objectives of this investigation were to understand transplacental transport of iron by secreted uteroferrin (UF) and haemophagous areas of water buffalo placenta and clarify the role(s) of blood extravasation at the placental‐maternal interface. Placentomes and interplacentomal region of 51 placentae at various stages of gestation were fixed, processed for light and transmission electron microscopy, histochemistry and immunohistochemistry. Haemophagous areas were present in placentomes collected between 4 and 10 months of pregnancy. Perl’s reaction for ferric iron was negative in placentomes, but positive in endometrial glands. Positive staining for UF indicated areas in which it was being taken up by phagocytosis and/or fluid phase pinocytosis in areolae of the interplacentomal mesenchyme, with little staining in endometrial stroma. Imunohistochemistry detected UF in trophectoderm of haemophagous regions of placentomes and in other parts of the foetal villous tree, but the strongest immunostaining was in the epithelial cells and lumen of uterine glands. Ultrastructural analyses indicated that erythrophagocytosis was occurring and that erythrocytes were present inside cells of the chorion that also contained endocytic vesicles and caveolae. Results of this study indicate that both the haemophagous areas of placentomes and the areolae at the interface between chorion and endometrial glands are important sites for iron transfer from mother to foetal‐placental tissues in buffalo throughout pregnancy.  相似文献   
32.
This study aimed to investigate the cardiovascular effects elicited by Dictyota pulchella, a brown alga, using in vivo and in vitro approaches. In normotensive conscious rats, CH(2)Cl(2)/MeOH Extract (CME, 5, 10, 20 and 40 mg/kg) from Dictyota pulchella produced dose-dependent hypotension (-4 ± 1; -8 ± 2; -53 ± 8 and -63 ± 3 mmHg) and bradycardia (-8 ± 6; -17 ± 11; -257 ± 36 and -285 ± 27 b.p.m.). In addition, CME and Hexane/EtOAc Phase (HEP) (0.01-300 μg/mL) from Dictyota pulchella induced a concentration-dependent relaxation in phenylephrine (Phe, 1 μM)-pre-contracted mesenteric artery rings. The vasorelaxant effect was not modified by the removal of the vascular endothelium or pre-incubation with KCl (20 mM), tetraethylammonium (TEA, 3 mM) or tromboxane A(2) agonist U-46619 (100 nM). Furthermore, CME and HEP reversed CaCl(2)-induced vascular contractions. These results suggest that both CME and HEP act on the voltage-operated calcium channel in order to produce vasorelaxation. In addition, CME induced vasodilatation after the vessels have been pre-contracted with L-type Ca(2+) channel agonist (Bay K 8644, 200 nM). Taken together, our data show that CME induces hypotension and bradycardia in vivo and that both CME and HEP induce endothelium-independent vasodilatation in vitro that seems to involve the inhibition of the Ca(2+) influx through blockade of voltage-operated calcium channels.  相似文献   
33.
In the horse, breeding induces a transient endometrial inflammation. A subset of mares are unable to resolve this inflammation, and they are considered susceptible to persistent mating‐induced endometritis PMIE Select seminal plasma proteins cysteine‐rich secretory protein‐3 (CRISP‐3) and lactoferrin have been shown to affect the innate immune response to sperm in vitro. The objective of this study was to determine whether the addition of CRISP‐3 and lactoferrin at the time of insemination had an effect on the mRNA expression of endometrial cytokines in susceptible mares after breeding. Six mares classified as susceptible to PMIE were inseminated during four consecutive oestrous cycles with treatments in randomized order of: 1 mg/ml CRISP‐3, 150 μg/ml lactoferrin, seminal plasma (positive control) or lactated Ringer's solution (LRS; negative control) to a total volume of 10 ml combined with 1 × 109 spermatozoa pooled from two stallions. Six hours after treatment, an endometrial biopsy was obtained for qPCR analysis of selected genes associated with inflammation (pro‐inflammatory cytokines interleukin (IL)‐1β, IL‐8, tumour necrosis factor (TNF)‐α, interferon (INF)‐γ, anti‐inflammatory cytokines IL‐1RN and IL‐10, and inflammatory‐modulating cytokine IL‐6). Seminal plasma treatment increased the mRNA expression of IL‐1β (p = .019) and IL‐8 (p = .0068), while suppressing the mRNA expression of TNF (p = .0013). Lactoferrin also suppressed the mRNA expression of TNF (p = .0013). In conclusion, exogenous lactoferrin may be considered as one modulator of the complex series of events resulting in the poorly regulated pro‐inflammatory response seen in susceptible mares.  相似文献   
34.
Common bean populations from crosses between lines of different races are thought to be more promising for selection of high yield potential than those from intra-racial crosses. Three distinct diallel crosses were made to test this hypothesis and to determine the possibility of substituting diallel crosses for multivariate techniques that estimate genetic divergence. The crosses were between races Mesoamerica × Mesoamerica, Mesoamerica × Durango and Jalisco, and Mesoamerica × Nueva Granada. The parents and the resulting F4 populations were evaluated at Lavras-MG, Lambari-MG and Patos de Minas-MG, Brazil. The diallel analysis of seed yield was done and the genetic divergence estimated by Mahalanobis distance. Estimates of general and specific combining ability indicated that some inter-racial populations were more promising for selection to increase seed yield than intra-racial populations. However, due to their undesirable seed color and size, and growth habit, especially in a short term breeding program, the chances of obtaining high yielding lines with an acceptable bean is reduced. Genetic divergence was not a good measure to choose the parents because usually, the most divergent groups included were not adapted lines. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
35.
The pink shrimp Farfantepenaeus brasiliensis is native in southern Brazil and is potentially suited for aquaculture. Under intensive culture, the accumulation of nitrogenous compounds results from excretion by the shrimp and from the processes of feed decomposition and nitrification. The objective of this study was to evaluate ammonia, nitrite, and nitrate toxicity effects on oxygen consumption of juvenile pink shrimp. Shrimps (initial weight 0.7 ± 0.15 g) were exposed over a period of 30 days to 50%, 100%, and 200% of the safe levels of total ammonia (TAN = 0.88 mg/L), nitrite (NO2? = 10.59 mg/L), and nitrate (NO3? = 91.20 mg/L) for the species. The specimens were individually collected and placed in respirometry chambers, where the oxygen consumption was measured over a period of two hours. Throughout the experiment there was no significant difference (p > 0.05) among treatments in terms of survival and growth. The pink shrimp juveniles exposed to nitrogen concentrations of 200% of the nitrite and nitrate safe level showed the highest oxygen consumption (p < 0.05).  相似文献   
36.
The occurrence of neurological disease in cattle caused by Bovine herpesvirus in 11 farms from southern Brazil between 1987 and 2007 is described. Twenty-two animals were necropsied. Major clinical signs included excessive salivation, nasal and ocular discharge, circling, recumbency, depression, incoordination, grinding of teeth, and paddling movements. Necropsy findings in 10 of 22 cattle included hyperemia and softening of the rostral portions of the telencephalic cortex, with flattening of gyri, and malacia. Cattle in 10 cases did not show any gross lesions. Histological examination in most cases revealed nonsuppurative and necrotizing meningoencephalitis with acute neuronal necrosis, edema, eosinophilic intranuclear inclusion bodies in astrocytes and neurons, and infiltration of gitter cells. No histologic lesions could be detected in 4 cases. The initial diagnosis was based upon the clinical, epidemiological, and pathological findings. The diagnosis was confirmed by virus isolation in cell culture followed by virus identification by a glycoprotein C-based polymerase chain reaction. Seven isolates were identified as Bovine herpesvirus 5, and 4 were identified as Bovine herpesvirus 1.  相似文献   
37.
The caprine arthrite encephalite (CAE) is a disease that affects especially dairy goat. The virus shows compartmentalization features, that allows it to hide at certain times during the course of the disease, making it difficult to control. The present study was conducted to identify the major seminal plasma protein profile of goats infected by CAE and its associations with seroconversion using Western blotting. Two groups containing five males each, were used in this experiment. The first group was composed by seropositive animals and the control by seronegative confirmed by Western blotting and PCR. The semen was collected through artificial vagina and after that, two-dimensional electrophoresis and MALDI-TOF MS were used. Seventy-five spots were identified in the goat seminal plasma gels, equivalent to 13 different proteins with more expression. The similar proteins found in both groups and related to reproduction were spermadhesin Z13-like, bodhesin and bodhesin-2, Lipocalin, protein PDC-109-like, and albumin. In infected goats, proteases such as arisulfatase A have been identified, whose function probably is related to metabolism control of sulfatides, involved to virus control. The other ones were bifunctional ATP-dependent dihydroxyacetone kinase/FAD-AMP lyase, cathepsin F isoform X1, disintegrin and metalloproteinase domain-containing protein 2-like isoform X1, clusterin, carbonic anhydrase 2, electron transfer flavoprotein subunit beta, and epididymal secretory glutathione peroxidase. The results of this study show the reaction of the innate immune system against chronic infection of goats by CAE.  相似文献   
38.
Despite evidences that seminal leucocytes could affect semen quality, references for the frequency and concentration of these cells in bulls are not available. The aim of this study was to determine the normal concentration of leucocytes in beef bulls and to correlate this characteristic with semen quality. First, 57 bulls from artificial insemination centres were evaluated to obtain the normal leucocytary profile values. Next, 382 bulls were subjected to breeding soundness evaluation. The average concentration of leucocytes in bovine semen was 4.73 × 106/ml. Unsatisfactory bulls showed a higher number of leucocytes/field than that in the satisfactory ones. Logistic regression analysis revealed that the unsatisfactory bulls showed 6.5‐fold more chances of having higher leucocyte counts than satisfactory ones. Values of up to 1 leucocyte/field in the bull ejaculate are considered physiologically normal, whereas >5 leucocytes/field is associated with poor semen quality.  相似文献   
39.
Cariniana estrellensis and Cedrela fissilis are native forest species from Brazil that are widely used for arborization of parks and recuperation of degraded areas. The production of seedlings from these two forest trees in nurseries is severely affected by fungal diseases. Morphological identification, sequencing analysis of three gene regions (TEF+ACT+ITS or TEF+TUB2 + ITS) and pathogenicity tests confirmed that fungi belonging to Botryosphaeriales are the aetiological agent of the diseases. This is the first report of Phyllosticta capitalensis causing leaf spots on C. estrellensis and Botryosphaeria dothidea causing canker on C. fissilis in forest nurseries in Brazil.  相似文献   
40.
Three new varieties of Passiflora hybrids were developed from crosses between P. sublanceolata J. M. MacDougal (ex P. palmeri var. sublanceolata Killip) versus P. foetida var. foetida L. Twenty putative hybrids were analyzed. Hybridizations were confirmed by RAPD and SSR markers. The RAPD primer UBC11 (5′-CCGGCCTTAC-3′) generated informative bands. The SSR primer A08FP1 amplified species-specific fragments and heterozygote status was observed with the two parent bands 240 and 280 bp. The molecular markers generated by primers were analyzed in terms of the presence or absence of specific informative bands. The morphological characterization of the hybrids enabled their differentiation into three groups, identified as: (1) Passiflora ‘Alva’, composed of five hybrid plants with white flowers, large corona, light purple filaments at base, white and purple/white banding to apex; (2) P. ‘Aninha’, composed of six hybrid plants with pale pink flowers, corona filaments reddish/purple at base, white, purple/white banding to apex; (3) P. ‘Priscilla’, composed of nine hybrid plants with white flowers, small corona, filaments dark purple at base, white and purple to apex. The genomic homology of parent plants was verified by cytogenetic analysis. Both parents were 2n = 22. Meiosis was regular in genitors and hybrids. Aneuploidy was observed at hybrid groups P. ‘Alva’ and P. ‘Priscilla’ (2n = 20). Other authors had already observed the same number of chromosomes for some P. foetida genotypes. Obtaining valuable interspecific hybrids opens up new perspectives to offer opportunities in agribusiness for producers and to arouse the interest of consumers into using passion flowers in the Brazilian ornamental plant market.  相似文献   
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