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91.
Luiz Henrique Agra Cavalcante-Silva Ana Carolina de Carvalho Correia José Maria Barbosa-Filho Bagnólia Araújo da Silva Bárbara Viviana de Oliveira Santos Daysianne Pereira de Lira Jéssica Celestino Ferreira Sousa George Emmanuel C. de Miranda Fabiana de Andrade Cavalcante Magna Suzana Alexandre-Moreira 《Marine drugs》2013,11(5):1553-1564
In this work, we investigated the spasmolytic effect of caulerpine, a bisindole alkaloid isolated from marine algae of the Caulerpa genus, on guinea pig ileum. Our findings indicated that caulerpine inhibited phasic contractions induced by carbachol (IC50 = 7.0 ± 1.9 × 10−5 M), histamine (IC50 = 1.3 ± 0.3 × 10−4 M) and serotonin (IC50 = 8.0 ± 1.4 × 10−5 M) in a non-selective manner. Furthermore, caulerpine concentration-dependently inhibited serotonin-induced cumulative contractions (pD′2 = 4.48 ± 0.08), shifting the curves to the right with Emax reduction and slope of 2.44 ± 0.21, suggesting a noncompetitive antagonism pseudo-irreversible. The alkaloid also relaxed the ileum pre-contracted by KCl (EC50 = 9.0 ± 0.9 × 10−5 M) and carbachol (EC50 = 4.6 ± 0.7 × 10−5 M) in a concentration-dependent manner. This effect was probably due to inhibition of Ca2+ influx through voltage-gated calcium channels (CaV), since caulerpine slightly inhibited the CaCl2-induced contractions in depolarizing medium without Ca2+, shifting the curves to the right and with Emax reduction. According to these results, the spasmolytic effect of caulerpine on guinea pig ileum seems to involve inhibition of Ca2+ influx through CaV. However, other mechanisms are not discarded. 相似文献
92.
Batista M González F Cabrera F Palomino E Castellano E Calero P Gracia A 《The Canadian veterinary journal. La revue veterinaire canadienne》2000,41(7):562-564
Anatomical, behavioral, histological, endocrinological, and cytogenetic characteristics were determined in a horned intersex goat. Histology of the gonads confirmed that the goat was a true hermaphrodite. Cytogenetic analysis showed that it was a chimera (60XX/60XY). Use of laparoscopy allowed determination of characteristics of the internal gonads. 相似文献
93.
Genetic typing of classical swine fever virus 总被引:18,自引:0,他引:18
Paton DJ McGoldrick A Greiser-Wilke I Parchariyanon S Song JY Liou PP Stadejek T Lowings JP Björklund H Belák S 《Veterinary microbiology》2000,73(2-3):137-157
Three regions of the classical swine fever virus (CSFV) genome that have been widely sequenced were compared with respect to their ability to discriminate between isolates and to segregate viruses into genetic groups. Sequence data-sets were assembled for 55 CSFVs comprising 150 nucleotides of the 5' non-translated region, 190 nucleotides of the E2 envelope glycoprotein gene and 409 nucleotides of the NS5B polymerase gene. Phylogenetic analysis of each data-set revealed similar groups and subgroups. For closely related viruses, the more variable or larger data-sets gave better discrimination, and the most reliable classification was obtained with sequence data from the NS5B region. No evidence was found for intertypic recombination between CSFVs. A larger data-set was also analysed comprising 190 nucleotides of E2 sequence from 100 CSFVs from different parts of the world, in order to assess the extent and global distribution of CSFV diversity. Additional groups of CSFV are evident from Asia and the nomenclature of Lowings et al. (1996) [Lowings, P., Ibata, G., Needham, J., Paton, D., 1996. J. Gen. Virol. 77, 1311-1321] needs to be updated to accommodate these. A tentative assignment, adapting rather than overturning the previous nomenclature divides CSF viruses into three groups with three or four subgroups: 1.1, 1.2, 1.3; 2.1, 2.2, 2.3; 3.1, 3.2, 3.3, 3.4. The expanding data-base of CSFV sequences should improve the prospects of disease tracing in the future, and provide a basis for a standardised approach to ensure that results from different laboratories are comparable. 相似文献
94.
Gaspar Soria Miguel F. Lavín Iván Martínez‐Tovar Alberto Macías‐Duarte 《Aquaculture Research》2013,44(9):1383-1398
We evaluated recruitment of larvae of catarina scallop, Argopecten ventricosus, in the area of Puerto Peñasco, NE Gulf of California. We moored artificial collectors in six sites from June 2007 to August 2008 and replaced them every 2 months. We used monthly (July 2002–September 2011) sea surface temperature (SST, °C) and surface chlorophyll‐a concentration (SSChl, mg m?3) Aqua/MODIS satellite data to describe seasonal environmental behaviour study area. Also, we recorded bottom temperature at each site every 4 h, and every 2 months measured sea surface salinity, temperature and dissolved oxygen. We used a repeated measures anova to evaluate differences in the number of recruited spat between main factors, and analysed the presence of multimodal spat shell size frequency distributions. Overall, spat recruitment was negatively correlated with seawater temperature and showed higher spat recruitment abundances throughout winter, which is the season with the highest surface chlorophyll a concentration. We estimated multimodal shell size frequency distributions characterized by more than one modal size. The natural collection of A. ventricosus spat on artificial collectors in the area can be successfully performed over a protracted period (November–December to May–June). Our results extend the area where collection of A. ventricosus spat can be successful. 相似文献
95.
I. Halila M. J. Cobos J. Rubio T. Millán M. Kharrat M. Marrakchi J. Gil 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(1):87-92
A second gene conferring resistance to the chickpea wilt pathogen, Fusarium oxysporum f. sp ciceris race 0, has been mapped to linkage group 2 (LG2) of the chickpea genetic map. Resistance to race 0 is controlled by two genes
which segregate independently; one present in accession JG62 (Foc0
1
/foc0
1
) and mapping to LG5 and the second present in accession CA2139 (Foc0
2
/foc0
2
) but remaining unmapped. Both genes separately confer complete resistance to race 0 of the wilt pathogen. Using a Recombinant
Inbred Line (RIL) population that segregated for both genes (CA2139 × JG62) and the genotypic information provided by two
markers flanking Foc0
1
/foc0
1
ten resistant lines containing the resistant allele Foc0
2
/foc0
2
were selected. Genotypic analysis using these ten resistant lines paired with ten susceptible RILs, selected in the same
population, revealed that sequence tagged microsatellite sites (STMS) markers sited on LG2 were strongly associated with Foc0
2
/foc0
2
. Linkage analysis, using data from two mapping populations (CA2139/JG62 and CA2156/JG62), located Foc0
2
/foc0
2
in a region where genes for resistance to wilt races 1, 2, 3, 4 and 5 have previously been reported and which is highly saturated
with tightly-linked STMS markers that could be used in marker-assisted selection (MAS). 相似文献
96.
Gimenez G Florin-Christensen M Belaunzarán ML Isola EL Suárez CE Florin-Christensen J 《Veterinary immunology and immunopathology》2007,119(3-4):171-179
Erythrocytes of bovines and other ruminants have a strikingly anomalous phospholipid composition, with low or absent phosphatidylcholine (PC) together with high sphingomyelin (SM) content. Here, we report the presence in normal bovine serum of high levels of anti-phospholipid antibodies of IgM isotype against, PC and the phosphono analogue of phosphatidylethanolamine, aminoethylphosphonolipid (AEPL), normally produced by rumen ciliates. In contrast, no antibodies were detected against SM or N-acyl-phosphatidylethanolamine (NAPE), the major components of bovine erythrocytes. In addition, we found that exposure of the ciliate Tetrahymena thermophila to bovine serum results in rapid lysis, an effect that was inhibited by adsorption of the serum with SM/AEPL liposomes. Furthermore, incubation with bovine serum had a similar effect on freshly obtained ruminal ciliates, and the lytic activity was eliminated by pre-adsorption of the serum with SM/PE liposomes. The ruminant mode of life with its concomitant ciliate fauna is hereby linked to the peculiar conformation of bovine erythrocyte membranes. We propose that the unique phospholipid composition of bovine erythrocytes appears as an evolutionary adaptation to tolerate the lytic effects of anti-phospholipid antibodies generated against AEPL, a membrane component of the huge mass of ruminal ciliates, necessary commensals of this group of mammals. 相似文献
97.
Gogorza LM Morán PE Larghi JL Seguí R Lissarrague C Saracco M Braun M Esteban EN 《Preventive veterinary medicine》2005,72(1-2):49-54; discussion 215-9
Detection of bovine virus diarrhoea virus (BVDV) in one vaccinated beef cattle and three non-vaccinated dairy herds was investigated on peripheral blood leukocytes (PBL) with or without previous treatment followed by a capture ELISA (cELISA). Using the combination of PHA and polycation treatment, PBL from 229 seropositive cattle were studied and could be classified in four different states of BVDV infection. Lysed PBL from four animals were directly positive in cELISA (Category I), PBL of 17 animals were positive after PHA stimulation (Category II), 15 animals were positive only after PHA stimulation plus polycation treatment (Category III), while virus could not be detected in 193 seropositive cattle. Wild-type BVDV strains were isolated by co-culture on polycation-treated MDBK cells from 11 of these seropositive animals. BVDV antibodies of these same animals were able to neutralize their own virus, indicating that virus persists in PBL in spite of strain-specific antibodies. No apparent change of leukocyte subpopulations could be detected in any category of virus-positive animals. Thus, BVDV may be present in the PBL of some cattle, even in the presence of a specific active immune response. 相似文献
98.
Salvador Becerra-Rodríguez Víctor Manuel Medina-Urrutia Marciano Manuel Robles-González Timothy Williams 《Euphytica》2008,164(1):27-36
Grapefruit growers in the tropics require information about existing and new citrus cultivars with high productivity potential.
The objective of this study was to determine the growth, yield, and fruit quality performance of seven pigmented and four
white grapefruit cultivars under the dry tropic conditions of Colima, Mexico. The trees were budded on sour orange (Citrus aurantium L.) rootstock and planted at a distance of 8 × 4 m. ‘Oroblanco’ and ‘Marsh Gardner’ white-fleshed grapefruit cultivars and
‘Chandler’, a pink-fleshed pummelo, were the largest trees with the greatest height (5.0–5.6 m), canopy diameter (6.2–6.3 m),
trunk diameter (21.9–23.3 cm), and canopy volume (109–123 m3). Lower height (4.3–4.8 m) and canopy volume (73–96 m3), but with similar canopy diameter to the previously mentioned cultivars, were recorded for the remaining pigmented cultivars.
‘Chandler’ pummelo and four pigmented grapefruit cultivars (‘Shambar’, ‘Río Red’, ‘Ray Ruby’, and ‘Redblush #3’) had yearly
productions of 34.8, 34.9, 34.1, 32.7, and 30.6 ton ha−1, respectively. The most productive white grapefruit cultivar was ‘Marsh Gardner’ (30.5 ton ha−1). Grapefruit cultivars having the largest fruit size showed a higher inverse relationship between fruit weight and yield
than those with small fruit. Most genotypes had higher values of fruit weight, juice content, and maturity index than those
required by the local market. The most promising grapefruit cultivars based on their acceptable growth, yield superior to
30 ton ha−1, and acceptable fruit color were ‘Río Red’, ‘Shambar’, ‘Ray Ruby’, and ‘Redblush #3’. 相似文献
99.
Effect of dietary Schizochytrium microalga oil and fish oil on plasma cholesterol level in rats 下载免费PDF全文
T. Komprda O. Škultéty S. Křížková G. Zorníková V. Rozíková R. Krobot 《Journal of animal physiology and animal nutrition》2015,99(2):308-316
The purpose of the study was to test the hypothesis that the dietary oils with different content of n‐3 polyunsaturated fatty acids (PUFA) eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) affect plasma lipid level in rats in a different degree. The diets with 6% of fish oil (FO) and Schizochytrium microalga oil (SchO; EPA+DHA content in the diets 9.5 + 12.3 and 2.6 + 29.5% of the sum of total fatty acids, respectively) were used; the diet with 6% of safflower oil (high content of n‐6 PUFA linoleic acid, 65.5%; EPA+DHA content 0.7 + 0.9%) was used as a control. The difference between FO and SchO was established only in the case of plasma triacylglycerol (TAG) level: plasma TAG of the FO‐fed rats did not differ from the control rats (p > 0.05), while SchO decreased (p < 0.05) plasma TAG to 46% of the control. On the other hand, FO and SchO decreased (p < 0.05) total plasma cholesterol (TC) in rats in the same extent, to 73% of the control. Regarding the underlying mechanisms for the TC decrease, both SchO and FO up‐regulated hepatic Insig‐1 gene (181 and 133% of the control; p < 0.05), which tended (p = 0.15 and p = 0.19 respectively) to decrease the amount of hepatic nSREBP‐2 protein (61 and 66% of the control). However, neither SchO nor FO influenced hepatic 3‐hydroxy‐3‐methyl‐glutaryl‐CoA reductase gene expression (p > 0.05); SchO (but not FO) increased (p < 0.05) low‐density lipoprotein receptor mRNA in the liver. It was concluded that the decrease of total plasma cholesterol might be caused by an increased cholesterol uptake from plasma into the cells (in the case of SchO), but also by other (in the present study not tested) mechanisms. 相似文献
100.
Recommendations are given saying that sugar-to-crude fibre rations of not more than 1.7:1 and sugar-to-urea ratios of 12:1 should be used in the fattening of cattle fed urea-supplemented rations of roughages in which 40% to 50% of the crude protein content of the ration had been replaced by urea. The amount of sugar per kg live-weight should not exceed 4 g. Higher quantities reduce the digestibility of crude fibre and, additionally, decrease the NH3 level and the pH in the rumen. At the same time the amount of volatile fatty acids is increased while the content of ruminal acetic acid decreases. Variations in the sugar-to-starch ratio had no statistically significant influence on the nitrogen balance whereas it was found that increasing quantities of sugar significantly decreased the digestibility of crude fibre. The proportional content of sugar in the readily metabolisable carbohydrates contained in the ration should not exceed 20% to 50%. 相似文献