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91.
Eduardo A. Almeida Afonso Celso Dias Bainy Osmar F. Gomes Paolo Di Mascio 《Journal of experimental marine biology and ecology》2005,318(1):21-30
Mussels Perna perna were exposed to air for 24 h showing a clear increase in the levels of lipid peroxidation and oxidative DNA damage, measured as 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodGuo). The levels of lipid peroxidation increased both in the digestive gland and gills, while oxidative DNA damage increased only in the gills. After the 24 h of air exposure, mussels were re-submersed for a period of 3 h, leading values to return to a pre-aerial exposure levels. Control animals were kept immersed during the whole period. Several antioxidant and complementary enzymes (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G6PDH), glutathione S-transferase (GST) and the levels of total glutathione (Total GSH) were assayed in a second set of experiments where one group of mussels were exposed to air for 18 h and other to 1 h re-submersion after 18 h aerial exposure. Only a 52% increase in the glutathione S-transferase activity was observed in the digestive gland, which remained elevated to about 40% after 1 h re-submersion, showing that defense systems can be modulated even during oxygen deprivation in P. perna. The DNA and lipid oxidative damage observed after aerial exposure indicates that mussels face an oxidative challenge, and are able to counteract such an “insult” as values of lipid peroxidation and DNA damage returned to control values after 3 h re-submersion. 相似文献
92.
It is generally considered that stress causes decreased immune function in fish. In this study we examined in Atlantic salmon (Salmo salar Linnaeus) the effects of both short- (a single 15s out of water) and long-term (4 weeks of daily handling 15s out of water) stress on plasma cortisol (free and total) and glucose levels, expression of interleukin-1beta (IL-1beta) and survival of head kidney (HK) macrophages under culture with Aeromonas salmonicida. In the short-term study, samples were collected prior to the application of the stressor, and at 1, 3, 6, 12 and 24h post stress. Free and total plasma cortisol levels and the percentage of free cortisol increased significantly in the stressed group at 1 and 3h post stress. Plasma glucose levels were significantly higher than those of control fish at 1, 3 and 6h post stress. Constitutive expression of IL-1beta in macrophages isolated from head kidneys in stressed fish was significantly higher at 1 and 3h post stress. However, lipopolysaccharide (LPS) stimulated expression of IL-1beta in HK macrophages, exhibited significantly higher fold increases in unstressed fish compared to stressed fish. In the long-term study, with the exception of an increase in plasma glucose levels at 1 week, there were no significant differences in stress parameters between groups. There was a significantly higher constitutive IL-1beta expression in macrophages isolated from stressed fish over the first 2 weeks. At weeks 1, 2 and 3 the magnitude of IL-1beta response of isolated HK macrophages to LPS stimulation was reduced in >90% of the stressed fish. At 4 weeks there was no significant difference in inducible IL-1beta expression between the groups. Macrophages isolated from stressed fish also showed significantly decreased survival when exposed to A. salmonicida. This study shows a clear pattern from repeated handling stress, whereby effects on immune cells begin with increased constitutive expression of IL-1beta, followed by decreased stimulation of leucocytes by extracellular antigen, and finally decreased leukocyte survival when exposed to A. salmonicida. The implications of these changes in the immune system will be discussed with respect to the use of classical indicators of stress to predict possible effects on the immune system of fish. 相似文献
93.
Preservation of bovine preantral follicle viability and ultra-structure after cooling and freezing of ovarian tissue 总被引:1,自引:0,他引:1
Celestino JJ dos Santos RR Lopes CA Martins FS Matos MH Melo MA Báo SN Rodrigues AP Silva JR de Figueiredo JR 《Animal reproduction science》2008,108(3-4):309-318
Bovine preantral follicles within ovarian fragments were exposed and cryopreserved in absence or presence of 1.5 M glycerol (GLY), ethylene glycol (EG), propanediol (PROH) or dimethyl sulfoxide (DMSO), undergoing a previous cooling at 20 °C for 1 h (protocol 1) or at 4 °C for 24 h (protocol 2) in 0.9% saline solution. At the end of each treatment, preantral follicles were classified as non-viable/viable when they were stained/not stained with trypan blue, respectively. To confirm viability staining, ultra-structure of the follicles was evaluated by transmission electronic microscopy (TEM). Data were compared by Chi-square test (P < 0.05). The storage of the ovaries at 20 °C for 1 h (78%) and 4 °C for 24 h (80%) did not reduce significantly the percentage of viable preantral follicles when compared to the control (75%). Similar results were obtained when ovarian fragments, respectively, for protocols 1 and 2, were exposed to MEM (78 and 77%), 1.5 M EG (78 and 71%), as well as frozen in 1.5 M EG (74 and 77%). Percentages of viable follicles in control were similar to those observed after exposure (75%) and freezing (76%) in presence of 1.5 M DMSO only when protocol 1 was used. The increase of the concentration from 1.5 to 3.0 M, for all cryoprotectants, reduced significantly the percentage of viable preantral follicles after freezing. Ultra-structural analysis has confirmed trypan blue results, showing that not only basement membrane, but also organelles, were intact in viable preantral follicles. In conclusion, ovarian tissue cooling at 4 °C for 24 h before cryopreservation (protocol 2) does not affect the viability of bovine preantral follicles when 1.5 M EG is present in the cryopreservation medium. 相似文献
94.
JF Yuan SJ Zhang O Jafer RA Furlong OE Chausiaux CA Sargent GH Zhang NA Affara 《BMC microbiology》2009,9(1):246
Background
Pseudorabies virus (PRV) is an alphaherpesviruses whose native host is pig. PRV infection mainly causes signs of central nervous system disorder in young pigs, and respiratory system diseases in the adult. 相似文献95.
Clonal diversity and conservation genetics of the medicinal plant Carapichea ipecacuanha (Rubiaceae)
de Oliveira LO Venturini BA Rossi AA Hastenreiter SS 《Genetics and molecular biology》2010,33(1):86-93
The roots of the understorey shrub Carapichea ipecacuanha (ipecac) have medicinal properties, and the uprooting of wild plants has supplied most of the world demand for this species. Although under severe population decline, C. ipecacuanha lacks legal protection. In the wild, the aerial stems of ipecac clump together to form clusters with well-defined borders. Cluster size may range from several to hundreds of aerial stems. To investigate the extent of clonality among aerial stems in ipecac clusters, we sampled 50 wild clusters (a total of 291 aerial stems) and screened them with 89 inter-simple sequence repeat (ISSR) markers. The 291 aerial stems were grouped into 42 putative clones. The clonal groups generally consisted of aerial stems from the same cluster, and there was little or no genetic differentiation among aerial stems at the cluster level. These findings suggest that strategies designed to conserve ipecac in situ should not rely upon census data, which are based on the number of aerial stems per cluster and the number of clusters per population, because such data greatly underestimate the species effective population size and genetic diversity. Our results also indicate that this species needs protection at a federal level. 相似文献
96.
97.
Carlos?ValenteEmail author Catarina?Afonso Catarina?I.?Gon?alves Miguel?A.?Alonso-Zarazaga Ana?Reis Manuela?Branco 《BioControl》2017,62(4):457-468
Classical biological control is a valuable tool against invasive pests, but concerns about non-target effects requires risk assessment studies. Potential non-target effects of Anaphes inexpectatus Huber and Prinsloo (Hymenoptera: Mymaridae) were assessed for a classical biological control programme against the Eucalyptus snout beetle, Gonipterus platensis (Marelli) (Coleoptera: Curculionidae). No-choice tests were conducted with 17 non-target species to assess host specificity, including 11 curculionids. In behavioural observations, A. inexpectatus showed no interest in any of the non-target species, but two weevil species were parasitised within five days of exposure, although at significantly lower rates than G. platensis. In choice tests, only one non-target, Hypera postica (Gyllenhal) (Coleoptera: Curculionidae), was parasitised, at a rate of 0.6%, while 50.0% of G. platensis eggs were parasitised. Based on the host specificity test results and the potential host fauna found in the target area, the likelihood of non-target effects resulting from the release of A. inexpectatus is considered to be negligible. 相似文献
98.
Luciano Pamplona de Góes Cavalcanti Lia Alves Martins Mota Gustavo Porto Lustosa Mayara Carvalho Fortes Davi Alves Martins Mota Ant?nio Afonso Bezerra Lima Ivo Castelo Branco Coelho Maria Paula Gomes Mour?o 《Memórias do Instituto Oswaldo Cruz》2014,109(1):93-98
In 2009, the World Health Organization (WHO) issued a new guideline that stratifies
dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or
without warning signs). To evaluate the new recommendations, we completed a
retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases
reported during an outbreak in 2011 in northeastern Brazil. We investigated 84
suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages
of the patients ranged from five-83 years and the median age was 29. According to the
DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as
having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO
classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without
warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A
better performance of the revised classification in the detection of severe clinical
manifestations allows for an improved detection of patients with SD and may reduce
deaths. The revised classification will not only facilitate effective screening and
patient management, but will also enable the collection of standardised surveillance
data for future epidemiological and clinical studies. 相似文献
99.
100.
Noutsou M Duarte AM Anvarian Z Didenko T Minde DP Kuper I de Ridder I Oikonomou C Friedler A Boelens R Rüdiger SG Maurice MM 《Journal of molecular biology》2011,405(3):773-786
The Wnt pathway tumor-suppressor protein Axin coordinates the formation of a critical multiprotein destruction complex that serves to downregulate β-catenin protein levels, thereby preventing target gene activation. Given the lack of structural information on some of the major functional parts of Axin, it remains unresolved how the recruitment and positioning of Wnt pathway kinases, such as glycogen synthase kinase 3β, are coordinated to bring about β-catenin phosphorylation. Using various biochemical and biophysical methods, we demonstrate here that the central region of Axin that is implicated in binding glycogen synthase kinase 3β and β-catenin is natively unfolded. Our results support a model in which the unfolded nature of these critical scaffolding regions in Axin facilitates dynamic interactions with a kinase and its substrate, which in turn act upon each other. 相似文献