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91.
Cassiano Monteiro-Neto Francisca Edna De Andrade Cunha Mara Carvalho Nottingham Maria Elizabeth Araújo Ierecê Lucena Rosa Glaura Maria Leite Barros 《Biodiversity and Conservation》2003,12(6):1287-1295
Brazil is one of the leading exporters of ornamental fishes, mostly freshwater; however, monitoring of the trade is nearly non-existent in the country. This paper provides an initial assessment of a new venture, the marine aquarium fish trade at Ceará State, northeast Brazil, aiming to document the species traded, to provide preliminary estimates of numbers of specimens traded, and to identify priorities in data collection and monitoring. A total of 143 species and 199 304 fishes were traded. From the total, 109 species were native and represented 84% of the fishes traded. Thirty-four exotic species figured on the permits and amounted to nearly 16% of the exports; however, most of them consist of misidentified native species. Nearly 90% of the fish trade was directed to the international market. Official figures represent an underestimation of the total number of captured specimens. 相似文献
92.
Miguel A. Gonz��lez-P��rez Pedro A. Sosa Elisabeth Rivero Edna A. Gonz��lez-Gonz��lez Agust��n Naranjo 《Annals of botany》2009,103(1):79-86
Background and Aims
Myrica rivas-martinezii is a critically endangered endemic of the laurel forest of the Canary Islands and co-occurs very close to M. faya. Some authors suggest that M. rivas-martinezii and M. faya are two morphs of the same species, so molecular markers were used to estimate the levels and structuring of genetic variation within and among natural populations in order to evaluate genetic relationships between these two congeners.Methods
Six polymorphic microsatellite (simple sequence repeat, SSR) markers were used to determine the genetic diversity and the genetic relationship between both Myrica species.Key Results
Most of the natural populations analysed were in Hardy–Weinberg equilibrium for both taxa. Analysis of molecular variance (AMOVA) for both species revealed that most of the genetic variability detected was contained within populations (92·48 and 85·91 % for M. faya and M. rivas-martinezii, respectively), which it is consistent with outcrossing and dioecious plants. Estimates of interpopulation genetic variation, calculated from FST and G′ST, were quite low in the two taxa, and these values did not increase substantially when M. rivas-martinezii and M. faya populations were compared. The UPGMA dendrogram based on Nei''s genetic distance clustered the populations by their island origin, independently of taxon. In fact, the mixture of individuals of both taxa did not appreciably disrupt the intrapopulational genetic cohesion, and only 3·76 % variation existed between species.Conclusions
All the results obtained using molecular markers indicate clearly that both taxa share the same genetic pool, and they are probably the same taxa. Considering that M. rivas-martinezii is classified as at risk of extinction, there should be a change of focus of the current management actions for the conservation of this putatively endangered Canarian endemic.Key words: Canary Islands, conservation genetics, microsatellites, Myrica rivas-martinezii, Myrica faya, plant conservation 相似文献93.
Egbert Hoiczyk Michael W. Ring Colleen A. McHugh Gertrud Schwär Edna Bode Daniel Krug Matthias O. Altmeyer Jeff Zhiqiang Lu Helge B. Bode 《Molecular microbiology》2009,74(2):497-517
Cell differentiation is widespread during the development of multicellular organisms, but rarely observed in prokaryotes. One example of prokaryotic differentiation is the Gram-negative bacterium Myxococcus xanthus . In response to starvation, this gliding bacterium initiates a complex developmental programme that results in the formation of spore-filled fruiting bodies. How the cells metabolically support the necessary complex cellular differentiation from rod-shaped vegetative cells into spherical spores is unknown. Here, we present evidence that intracellular lipid bodies provide the necessary metabolic fuel for the development of spores. Formed at the onset of starvation, these lipid bodies gradually disappear until they are completely used up by the time the cells have become mature spores. Moreover, it appears that lipid body formation in M. xanthus is an important initial step indicating cell fate during differentiation. Upon starvation, two subpopulations of cells occur: cells that form lipid bodies invariably develop into spores, while cells that do not form lipid bodies end up becoming peripheral rods, which are cells that lack signs of morphological differentiation and stay in a vegetative-like state. These data indicate that lipid bodies not only fuel cellular differentiation but that their formation represents the first known morphological sign indicating cell fate during differentiation. 相似文献
94.
Nicole Vlahovich Anthony J. Kee Chris Van der Poel Emma Kettle Delia Hernandez-Deviez Christine Lucas Gordon S. Lynch Robert G. Parton Peter W. Gunning Edna C. Hardeman 《Molecular biology of the cell》2009,20(1):400-409
The functional diversity of the actin microfilaments relies in part on the actin binding protein tropomyosin (Tm). The muscle-specific Tms regulate actin-myosin interactions and hence contraction. However, there is less known about the roles of the numerous cytoskeletal isoforms. We have shown previously that a cytoskeletal Tm, Tm5NM1, defines a Z-line adjacent cytoskeleton in skeletal muscle. Recently, we identified a second cytoskeletal Tm in this region, Tm4. Here we show that Tm4 and Tm5NM1 define separate actin filaments; the former associated with the terminal sarcoplasmic reticulum (SR) and other tubulovesicular structures. In skeletal muscles of Tm5NM1 knockout (KO) mice, Tm4 localization was unchanged, demonstrating the specificity of the membrane association. Tm5NM1 KO muscles exhibit potentiation of T-system depolarization and decreased force rundown with repeated T-tubule depolarizations consistent with altered T-tubule function. These results indicate that a Tm5NM1-defined actin cytoskeleton is required for the normal excitation–contraction coupling in skeletal muscle. 相似文献
95.
96.
Swa2p is an auxilin-like yeast protein that is involved in vesicular transport and required for uncoating of clathrin-coated vesicles. Swa2p contains a ubiquitin-associated (UBA) domain, which is present in a variety of proteins involved in ubiquitin (Ub)-mediated processes. We have determined a structural model of the Swa2p UBA domain in complex with Ub using NMR spectroscopy and molecular docking. Ub recognition occurs predominantly through an atypical interaction in which UBA helix α1 and the N-terminal part of helix α2 bind to Ub. Mutation of Ala148, a key residue in helix α1, to polar residues greatly reduced the affinity of the UBA domain for Ub and revealed a second low-affinity Ub-binding site located on the surface formed by helices α1 and α3. Surface plasmon resonance showed that the Swa2p UBA domain binds K48- and K63-linked di-Ub in a non-linkage-specific manner. These results reveal convergent evolution of a Ub-binding site on helix α1 of UBA domains involved in membrane protein trafficking. 相似文献
97.
Edna Grünblatt Camelia Maria Monoranu† Manuela Apfelbacher† Daniela Keller Tanja M. Michel‡ Irina Alafuzoff§§§§ Isidro Ferrer¶ Safa Al-Saraj Kathy Keyvani†† rea Schmitt‡‡ Peter Falkai‡‡ Jens Schittenhelm§§ Catriona McLean¶¶ Glenda M. Halliday††† Clive Harper‡‡‡ Jürgen Deckert Wolfgang Roggendorf† Peter Riederer 《Journal of neurochemistry》2009,110(5):1400-1408
Postmortem human brain tissue is widely used in neuroscience research, but use of tissue originating from different brain bank centers is considered inaccurate because of possible heterogeneity in sample quality. There is thus a need for well-characterized markers to assess the quality of postmortem brain tissue. Toward this aim, we determined tryptophan (TRP) concentrations, phosphofructokinase-1 and glutamate decarboxylase activities in 119 brain tissue samples. These neurochemical parameters were tested in samples from autopsied individuals, including control and pathological cases provided by 10 different brain bank centers. Parameters were assessed for correlation with agonal state, postmortem interval, age and gender, brain region, preservation and freezing methods, storage conditions and storage time, RNA integrity, and tissue pH value. TRP concentrations were elevated significantly ( p = 0.045) with increased postmortem interval; which might indicate increased protein degradation. Therefore, TRP concentration might be one useful and convenient marker for estimating the quality of human postmortem brain tissue. 相似文献
98.
99.
Vaccine-induced cellular immune responses reduce plasma viral concentrations after repeated low-dose challenge with pathogenic simian immunodeficiency virus SIVmac239
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Wilson NA Reed J Napoe GS Piaskowski S Szymanski A Furlott J Gonzalez EJ Yant LJ Maness NJ May GE Soma T Reynolds MR Rakasz E Rudersdorf R McDermott AB O'Connor DH Friedrich TC Allison DB Patki A Picker LJ Burton DR Lin J Huang L Patel D Heindecker G Fan J Citron M Horton M Wang F Liang X Shiver JW Casimiro DR Watkins DI 《Journal of virology》2006,80(12):5875-5885
The goal of an AIDS vaccine regimen designed to induce cellular immune responses should be to reduce the viral set point and preserve memory CD4 lymphocytes. Here we investigated whether vaccine-induced cellular immunity in the absence of any Env-specific antibodies can control viral replication following multiple low-dose challenges with the highly pathogenic SIVmac239 isolate. Eight Mamu-A*01-positive Indian rhesus macaques were vaccinated with simian immunodeficiency virus (SIV) gag, tat, rev, and nef using a DNA prime-adenovirus boost strategy. Peak viremia (P = 0.007) and the chronic phase set point (P = 0.0192) were significantly decreased in the vaccinated cohort, out to 1 year postinfection. Loss of CD4(+) memory populations was also ameliorated in vaccinated animals. Interestingly, only one of the eight vaccinees developed Env-specific neutralizing antibodies after infection. The control observed was significantly improved over that observed in animals vaccinated with SIV gag only. Vaccine-induced cellular immune responses can, therefore, exert a measure of control over replication of the AIDS virus in the complete absence of neutralizing antibody and give us hope that a vaccine designed to induce cellular immune responses might control viral replication. 相似文献
100.
Kárita Cláudia Freitas-Lidani Iara J de Messias-Reason Edna Aoba Y Ishikawa 《Memórias do Instituto Oswaldo Cruz》2014,109(4):442-447
The aim of the present study was to detect natural infection by Leishmania
(Leishmania) infantum in Lutzomyia longipalpis captured
in Barcarena, state of Pará, Brazil, through the use of three primer sets. With this
approach, it is unnecessary to previously dissect the sandfly specimens. DNA of
280 Lu. longipalpis female specimens were extracted from the
whole insects. PCR primers for kinetoplast minicircle DNA (kDNA), the mini-exon gene
and the small subunit ribosomal RNA (SSU-rRNA) gene of Leishmania
were used, generating fragments of 400 bp, 780 bp and 603 bp, respectively.
Infection by the parasite was found with the kDNA primer in 8.6% of the cases, with
the mini-exon gene primer in 7.1% of the cases and with the SSU-rRNA gene primer in
5.3% of the cases. These data show the importance of polymerase chain reaction as a
tool for investigating the molecular epidemiology of visceral leishmaniasis by
estimating the risk of disease transmission in endemic areas, with the kDNA primer
representing the most reliable marker for the parasite. 相似文献