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71.
72.
Aspidoras azaghal n. sp. was discovered during a multitaxonomic scientific expedition to the remote Amazon Terra do Meio region in tributaries to the rio Xingu basin, Pará, Brazil. The new species can be promptly distinguished from its congeners by the following combination of features: (a) absence of the first dorsal-fin element; (b) parieto-supraoccipital fontanel located medially on bone; (c) absence of a longitudinal dark-brown or black stripe along flank midline; (d) ventral surface of trunk covered by clearly smaller, irregular and/or roundish platelets; (e) inner laminar expansion of infraorbital 1 well developed; (f) relatively wide frontal bone, with width equal to half of entire length; (g) absence of a thick, longitudinal conspicuous dark-brown stripe along dorsal portion of flank; and (h) poorly developed serrations on posterior margin of the pectoral-fin spine. Besides morphological evidence, the molecular analyses indicated significant differences between the new species and its congeners, with A. albater and A. raimundi as its closest species, showing 6.53% of genetic differentiation in both cases. The intraspecific molecular data revealed gene flow (peer fixation index, FST = 0.05249, P > 0.05, for the cytochrome oxidase I (COI) marker and FST = -0.01466, P > 0.05, for the control region) between specimens upstream and downstream from a 30-m height waterfall at the type-locality, which therefore represent a single population. Furthermore, it was possible to observe a unidirectional gene flow pattern, with genetic diversity increasing in the downstream direction.  相似文献   
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The organogenic potential of root explants derived from cultured seedlings of Bixa orellana L. (annatto) was investigated in response to different incubation conditions and either 4.44 μM 6-benzyladenine, 4.54 μM Thidiazuron, or 4.56 μM Zeatin. Explants cultured in liquid media with agitation generally showed better development of adventitious buds versus explants cultured on semi-solid media. The most adventitious buds developed from explants cultured in liquid media under a 16-h photoperiod. Use of Zeatin and Thidiazuron promoted the development of more adventitious buds than 6-benzyladenine but morphological abnormalities among regenerating shoots and plants were observed. Fewer adventitious buds developed from explants cultured in liquid media supplemented with 6-benzyladenine, but the buds gave rise to the highest percentage of morphologically normal regenerated plants. Histological analyses showed that adventitious buds originated from cell proliferation within the pericycle, opposite the protoxylem poles of the explant. Seedling root tissue is useful for in vitro propagation of B. orellana.  相似文献   
75.
Chemometrics has been shown quite efficient to uncover relationships between chemical composition of a sample and its geographical origin. Forty propolis samples originated from the the South and South East of Brazil were analyzed by HPLC and 18 compounds of interest were studied which included: caffeic, p-coumaric and ferulic acids, and some of their derivatives, pinobanksin, a derivative of kaempferol and five phenolic compounds (assigned as 3-prenyl4-hydroxycinnamic acid (PHCA); 2,2-dimethyl-6-carboxyethnyl-2H-1-benzopyran (DCBE); 3,5-diprenyl-4-hydroxycinnamic acid (DHCA); compound E (still unknown) and 6-propenoic-2,2-dimethyl-8-prenyl-2H-1-benzopyran acid (DPB). Principal Component Analysis (PCA) indicated three different groups of propolis samples, having the same typical chromatogram, evaluated by HPLC. Samples from the South East group were rich in derivatives of kaempferol. Samples from the South group I had a high content of DPB compound, but a low concentration of kaempferol derivatives and of DCBEN compound. Samples from the South group II were characterized by a high concentration of DCBEN, DHCA, p-coumaric and DPB compounds. Therefore, the identification of new compounds in Brazilian propolis can give, useful information about the plant sources of a given geographic region.  相似文献   
76.
Inflammation is a known mechanism that facilitates HIV acquisition and the spread of infection. In this study, we evaluated whether curcumin, a potent and safe anti-inflammatory compound, could be used to abrogate inflammatory processes that facilitate HIV-1 acquisition in the female genital tract (FGT) and contribute to HIV amplification. Primary, human genital epithelial cells (GECs) were pretreated with curcumin and exposed to HIV-1 or HIV glycoprotein 120 (gp120), both of which have been shown to disrupt epithelial tight junction proteins, including ZO-1 and occludin. Pre-treatment with curcumin prevented disruption of the mucosal barrier by maintaining ZO-1 and occludin expression and maintained trans-epithelial electric resistance across the genital epithelium. Curcumin pre-treatment also abrogated the gp120-mediated upregulation of the proinflammatory cytokines tumor necrosis factor-α and interleukin (IL)-6, which mediate barrier disruption, as well as the chemokines IL-8, RANTES and interferon gamma-induced protein-10 (IP-10), which are capable of recruiting HIV target cells to the FGT. GECs treated with curcumin and exposed to the sexually transmitted co-infecting microbes HSV-1, HSV-2 and Neisseria gonorrhoeae were unable to elicit innate inflammatory responses that indirectly induced activation of the HIV promoter and curcumin blocked Toll-like receptor (TLR)-mediated induction of HIV replication in chronically infected T-cells. Finally, curcumin treatment resulted in significantly decreased HIV-1 and HSV-2 replication in chronically infected T-cells and primary GECs, respectively. All together, our results suggest that the use of anti-inflammatory compounds such as curcumin may offer a viable alternative for the prevention and/or control of HIV replication in the FGT.  相似文献   
77.
The Metabolic Models Reconstruction Using Genome-Scale Information (merlin) tool is a user-friendly Java application that aids the reconstruction of genome-scale metabolic models for any organism that has its genome sequenced. It performs the major steps of the reconstruction process, including the functional genomic annotation of the whole genome and subsequent construction of the portfolio of reactions. Moreover, merlin includes tools for the identification and annotation of genes encoding transport proteins, generating the transport reactions for those carriers. It also performs the compartmentalisation of the model, predicting the organelle localisation of the proteins encoded in the genome and thus the localisation of the metabolites involved in the reactions promoted by such enzymes. The gene-proteins-reactions (GPR) associations are automatically generated and included in the model. Finally, merlin expedites the transition from genomic data to draft metabolic models reconstructions exported in the SBML standard format, allowing the user to have a preliminary view of the biochemical network, which can be manually curated within the environment provided by merlin.  相似文献   
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79.

Background  

The genus Arachis is native to a region that includes Central Brazil and neighboring countries. Little is known about the genetic variability of the Brazilian cultivated peanut (Arachis hypogaea, genome AABB) germplasm collection at the DNA level. The understanding of the genetic diversity of cultivated and wild species of peanut (Arachis spp.) is essential to develop strategies of collection, conservation and use of the germplasm in variety development. The identity of the ancestor progenitor species of cultivated peanut has also been of great interest. Several species have been suggested as putative AA and BB genome donors to allotetraploid A. hypogaea. Microsatellite or SSR (Simple Sequence Repeat) markers are co-dominant, multiallelic, and highly polymorphic genetic markers, appropriate for genetic diversity studies. Microsatellite markers may also, to some extent, support phylogenetic inferences. Here we report the use of a set of microsatellite markers, including newly developed ones, for phylogenetic inferences and the analysis of genetic variation of accessions of A. hypogea and its wild relatives.  相似文献   
80.
Cyclopentenone prostaglandins (PGs) exhibit antiviral activity against RNA and DNA viruses in mammalian cell lines, and this effect has been associated with the induction of a heat shock protein (hsp70). We investigated the effect of prostaglandin A1 (PGA1) on the replication of vesicular stomatitis virus (VSV) in Aedes albopictus (mosquito) cells. PGA1 was found to inhibit VSV replication dose dependently. Virus yield was reduced to 50% (3 microg PGA1/ml) and to 95% with 8 microg PGA1/ml. Even with the dramatic reduction of virus production observed in cells treated with PGA1, VSV-specific protein synthesis was unaltered. Treatment of cells with PGA1 (5 microg/ml) stimulated the synthesis of a polypeptide identified as a heat-shock protein (hsp) by immunoblot analysis. PGA1 induced hsp70 synthesis in uninfected cells. However, in VSV-infected cells the induction of hsp70 by PGA1 was reduced. This is the first report of antiviral effects of PGs affecting the replication of VSV in a mosquito cell line.  相似文献   
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