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71.
72.
Pérez JM González FJ Granados JE Pérez MC Fandos P Soriguer RC Serrano E 《Journal of wildlife diseases》2003,39(1):209-215
We studied blood samples from 529 Spanish ibexes (Capra pyrenaica) from different Andalusian mountain ranges in southern Spain, primarily from Sierra Nevada. For each sample, 13 hematologic and 32 biochemical parameters were analyzed. Within this database, we selected values obtained from live, free-ranging, physically restrained, clinically normal animals to determine reference intervals for these parameters. Distribution of values within each parameter was determined and differences in values between sex and age classes also were determined. We found significant differences in eight biochemical parameters among male and female ibexes. Significant differences in values for 20 hematologic and biochemical parameters between age classes also were found. 相似文献
73.
Novel insect cell line capable of complex N-glycosylation and sialylation of recombinant proteins 总被引:1,自引:0,他引:1
Paucimannose or oligomannose structures are usually attached to glycoproteins produced by insect cells, while mammalian glycoproteins usually have complex glycans. The lack of complex glycosylation has limited the use of the insect cell baculovirus expression vector system (BEVS), despite its high productivity and versatility. The availability of cell lines capable of complex glycosylation can overcome such a problem and potentially increase the utility of BEVS. In this work the capability of two novel cell lines, one from Pseudaletia unipuncta (A7S) and one from Danaus plexippus (DpN1), to produce and glycosylate a recombinant protein (secreted human placental alkaline phosphatase, SeAP) was assessed. SeAP produced by Tn5B1-4 cells at a low passage number (<200) was utilized for comparison. The optimal conditions for the production of SeAP by DpN1 cells were defined, and the glycosylation profiles of SeAP produced by the cell lines were quantitatively determined. Both the A7S and the DpN1 cells produced lower concentrations of SeAP than the Tn5B1-4 cells. Less than 5% of the glycans attached to SeAP produced by the Tn5B1-4 cells had complex forms. Glycans attached to SeAP from A7S cells contained 4% hybrid and 8% complex forms. Galactosylated biantennary structures were identified. Glycans attached to SeAP produced by the DpN1 cell line had 6% hybrid and 26% complex forms. Of the complex forms in SeAP from DpN1, 13% were identified as sialylated glycans. The galactosyltransferase activity of the three cell lines was measured and correlated to their ability to produce complex forms. Even though neither novel cell line produced as much recombinant protein as the Tn5B1-4 cells, the glycosylation of SeAP expressed by both cell lines was more complete. These novel cell lines represent interesting alternatives for the production of complex glycosylated proteins utilizing the BEVS. 相似文献
74.
Gorostiaga EM Navarro-Amézqueta I Cusso R Hellsten Y Calbet JA Guerrero M Granados C González-Izal M Ibáñez J Izquierdo M 《PloS one》2010,5(10):e13486
Information about anaerobic energy production and mechanical efficiency that occurs over time during short-lasting maximal exercise is scarce and controversial. Bilateral leg press is an interesting muscle contraction model to estimate anaerobic energy production and mechanical efficiency during maximal exercise because it largely differs from the models used until now. This study examined the changes in muscle metabolite concentration and power output production during the first and the second half of a set of 10 repetitions to failure (10RM) of bilateral leg press exercise. On two separate days, muscle biopsies were obtained from vastus lateralis prior and immediately after a set of 5 or a set of 10 repetitions. During the second set of 5 repetitions, mean power production decreased by 19% and the average ATP utilisation accounted for by phosphagen decreased from 54% to 19%, whereas ATP utilisation from anaerobic glycolysis increased from 46 to 81%. Changes in contraction time and power output were correlated to the changes in muscle Phosphocreatine (PCr; r = −0.76; P<0.01) and lactate (r = −0.91; P<0.01), respectively, and were accompanied by parallel decreases (P<0.01-0.05) in muscle energy charge (0.6%), muscle ATP/ADP (8%) and ATP/AMP (19%) ratios, as well as by increases in ADP content (7%). The estimated average rate of ATP utilisation from anaerobic sources during the final 5 repetitions fell to 83% whereas total anaerobic ATP production increased by 9% due to a 30% longer average duration of exercise (18.4±4.0 vs 14.2±2.1 s). These data indicate that during a set of 10RM of bilateral leg press exercise there is a decrease in power output which is associated with a decrease in the contribution of PCr and/or an increase in muscle lactate. The higher energy cost per repetition during the second 5 repetitions is suggestive of decreased mechanical efficiency. 相似文献
75.
Eduardo Gómez-Casado G. Vargas-Alarcón Jorge Martinez-Laso Mercedes Perez-Blas Julio Granados Zulay Layrisse Fabiola Montoya Pilar Varela A. Arnaiz-Villena 《Immunogenetics》1997,46(6):469-476
HLA-B is the most polymorphic of the major histocompatibility complex classical class I loci. This polymorphism is mainly in exons
2 and 3, which code for the molecule’s α1 and α2 domains and include the antigenic peptide binding site. Recent studies have
indicated that not only exons but also the intron 2 region may be involved in the generation of certain HLA-B alleles such as B
*
3906 and B
*
1522. To study the degree of intron 2 participation and the mechanisms that generate polymorphism at the HLA-B locus, intron 1 and 2 sequences from the HLA-B35, -B5, -B16 and -B15 groups of alleles were obtained. A group-specific intronic
polymorphism was found: namely, B
*
5301 shows intron 1 and 2 sequences identical to those found in all B35 alleles studied. On the other hand, B
*
5101 and B
*
52012 show the same intron 1 and 2 sequences and their intron 1 is the same as that found in the B35 group. This suggests that B5 and B35 groups of alleles may have arisen from a common ancestor. All known B16 alleles show the same introns 1 and 2, with the exception of B
*
39061 and B
*
39062, and all B15 alleles also bear the same introns 1 and 2, with the exception of B
*
1522. Variability at intron 1 is more restricted than at intron 2, and the use of intron 1 for HLA-B allele phylogenetic analysis is better for grouping alleles of a postulated common origin. In conclusion, there is a remarkable
conservation of intronic sequences within related HLA-B alleles, which probably reflects a common origin and perhaps a selective force avoiding DNA changes. Intronic sequences are
also potentially useful to design DNA typing strategies.
Received: 11 March 1997 / Revised: 29 May 1997 相似文献
76.
Ricardo Rodríguez-Estrella José Juan Pérez Navarro Bruno Granados Laura Rivera 《Biological invasions》2010,12(10):3389-3393
The rubber vine (Cryptostegia grandiflora) is an aggressive, invasive weed species with a high spreading potential that has caused great ecological impacts and economic costs to the areas in which it has been introduced. In Mexico, there is little information on the invasion of this species. In Baja California Sur (BCS), the first record of the species is documented from 1935 in one oasis. Despite the ecological problems that this invasive species may cause in the oases of BCS, little was known about its distribution and status. The aim of this work was to document the presence of the rubber vine in 57 oases in Baja California Sur during 2006–2008. The rubber vine was present in 22 (39%) of the sampled oases. The distribution pattern strongly suggests that the rubber vine had been introduced by the local population and then spread in the oasis and into the vicinity of streams and canyons. Vertebrate and invertebrate endemic oasis-dependent species may be at risk because the rubber vine can become a dominant species in oases and because reptiles and birds may not use the plant and instead avoid the areas where it grows. This is risky in fragile ecosystems immersed in a desert. Education and eradication of rubber vines from oases should be urgently done. 相似文献
77.
Gamboa R Hernandez-Pacheco G Hesiquio R Zuñiga J Massó F Montaño LF Ramos-Kuri M Estrada J Granados J Vargas-Alarcón G 《Human biology; an international record of research》2000,72(6):975-981
Apolipoprotein E (APOE) genotypes were determined in 75 Mazatecan Indians and 83 Mexican mestizos. APOE allele and genotype frequencies in Mazatecans and mestizos were similar, with high frequencies of the APOE*3 allele (0.900 and 0.915, respectively) and the E3/3 genotype (0.813 and 0.831, respectively) and an absence in both samples of the APOE*2 allele. Our data are similar to those previously described for Mexican-American and Mayan populations, which show the highest frequency worldwide of the APOE*3 allele and the E3/3 genotype. Mazatecans and mestizos also show a decreased frequency of the APOE*4 allele when compared to other Amerindian groups. The absence of the APOE*2 allele has also been reported in other Amerindian groups such as Mayans and Cayapa, whereas in Caucasians the average frequency of this allele is about 8%. Our data are in agreement with previous reports showing absence of the APOE*2 allele in Native American groups. These findings suggest that the APOE*2 allele was absent in humans from northern Asia who settled in the Arctic and populated the American continent. 相似文献
78.
Monica Granados Sean Duffy Christopher W. McKindsey Gregor F. Fussmann 《Ecology and evolution》2017,7(13):5016-5025
Intraguild predation (IGP) is an omnivorous food web configuration in which the top predator consumes both a competitor (consumer) and a second prey that it shares with the competitor. This omnivorous configuration occurs frequently in food webs, but theory suggests that it is unstable unless stabilizing mechanisms exist that can decrease the strength of the omnivore and consumer interaction. Although these mechanisms have been documented in native food webs, little is known about whether they operate in the context of an introduced species. Here, we study a marine mussel aquaculture system where the introduction of omnivorous mussels should generate an unstable food web that favors the extinction of the consumer, yet it persists. Using field and laboratory approaches, we searched for stabilizing mechanisms that could reduce interaction strengths in the food web. While field zooplankton counts suggested that mussels influence the composition and abundance of copepods, stable isotope results indicated that life‐history omnivory and cannibalism facilitated the availability of prey refugia, and reduced competition and the interaction strength between the mussel omnivore and zooplankton consumers. In laboratory experiments, however, we found no evidence of adaptive feeding which could weaken predator–consumer interactions. Our food web study suggests that the impact of an introduced omnivore may not only depend on its interaction with native species but also on the availability of stabilizing mechanisms that alter the strength of those interactions. 相似文献
79.
Jian-xiao Tian Chang-you Li Gui-ling Zheng Guo-xun Li Ping Wang R. R. Granados 《Insect Science》2004,11(3):165-171
Abstract The characteristics of a cultured cell line do not always remain stable and may change upon continuous passage. Most continuous cell lines, even after cloning, possess several genotypes that are constantly changing. There are numerous selective and adaptive culture processes, in addition to genetic instability, that may improve phenotypic change in cell growth, virus susceptibility, gene expression, and production of virus. Similar detrimental effects of long term passaging of insect cells have also been reported for continuous cell lines, for example, Tn5B1–4 cells, which are the most widely used for the baculovirus expression vector system (BEVS), provide superior production of recombinant proteins, however, this high productivity may be more evident in low passage cells. In this paper, we describe the isolation of a cell clone, Tn5B-40, from low passage Tn5B1–4 cells. The growth characteristics, productions of virus, and high level of recombinant protein productions were determined. The results showed the susceptibility of both clone and Tn5B1–4 cells to wild-type AcNPV was approximately the same rate with over 95% of infection; when the cloned cells were infected with recombinant baculoviruses expressing ß -galactosidase and secreted alkaline phosphatase (SEAP), expression of the recombinant proteins from the cloned cells exceeded that from the parental Tn5B1–4 cells. 相似文献
80.
Pérez JM Granados JE Moreno V Calabuig G Moço G Serrano E 《Parasite (Paris, France)》2006,13(4):305-310
Third-instar Oestrus caucasicus larvae (n = 236) obtained from Iberian ibex, Copra pyrenaica, were reared in a laboratory to obtain adult flies. They were maintained at a temperature of 21.9 +/- 2.7 degrees C and a relative humidity of 38.9 +/- 8.0 %. In all, 78 imagos emerged (33.1 %), with a sex-ratio at emergence not differing significantly from 1:1; 25 larvae did not complete pupariation. A total of 14 adult flies (17.9 % of the adults obtained) showed malformations, mainly in their wings. The pupariation period lasted around 30 hours and the pupal stage lasted on average 29.8 +/- 6.8 days. The success of pupation in both sexes was mainly determined by the weight of the larvae. Sexual dimorphism, with higher weights in females, was evident in third-instar arvae, pupae and adults. The mean longevity of adult flies was 224.8 +/- 91.4 hours and males generally survived for onger than the females. 相似文献