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1.
Luis MP Ceríaco 《Journal of ethnobiology and ethnomedicine》2012,8(1):1-13
Background
Human values and folklore of wildlife strongly influence the effectiveness of conservation efforts. These values and folklore may also vary with certain demographic characteristics such as gender, age, or education. Reptiles and amphibians are among the least appreciated of vertebrates and are victims of many negative values and wrong ideas resulting from the direct interpretation of folklore. We try to demonstrate how these values and folklore can affect the way people relate to them and also the possible conservation impacts on these animals.Methods
A questionnaire survey distributed to 514 people in the district of Évora, Portugal, was used to obtain data regarding the hypothesis that the existence of wrong ideas and negative values contributes to the phenomenon of human-associated persecution of these animals. A structural equation model was specified in order to confirm the hypothesis about the possible relationships between the presence of perceptions and negative values about amphibians and reptiles and persecution and anti-conservation attitudes. Sociodemographic variables were also added.Results
The results of the model suggest that the presence of folklore and negative values clearly predicts persecution and anti-conservation attitudes towards amphibians and reptiles. Also, the existence of folklore varies sociodemographically, but negative values concerning these animals are widespread in the population.Conclusions
With the use of structural equation models, this work is a contribution to the study of how certain ideas and values can directly influence human attitudes towards herpetofauna and how they can be a serious conservation issue. 相似文献2.
Sampling properties of DNA sequence data in phylogenetic analysis 总被引:20,自引:6,他引:20
We inferred phylogenetic trees from individual genes and random samples of
nucleotides from the mitochondrial genomes of 10 vertebrates and compared
the results to those obtained by analyzing the whole genomes. Individual
genes are poor samples in that they infrequently lead to the whole-genome
tree. A large number of nucleotide sites is needed to exactly determine the
whole-genome tree. A relatively small number of sites, however, often
results in a tree close to the whole-genome tree. We found that blocks of
contiguous sites were less likely to lead to the whole-genome tree than
samples composed of sites drawn individually from throughout the genome.
Samples of contiguous sites are not representative of the entire genome, a
condition that violates a basic assumption of the bootstrap method as it is
applied in phylogenetic studies.
相似文献
3.
Iris M Costa Tallybia HT Nasser Marilene Demasi Rafaella MP Nascimento Luis ES Netto Sayuri Miyamoto Fernanda M Prado Gisele Monteiro 《BMC microbiology》2011,11(1):268
Background
The gene YCL047C, which has been renamed promoter of filamentation gene (POF1), has recently been described as a cell component involved in yeast filamentous growth. The objective of this work is to understand the molecular and biological function of this gene.Results
Here, we report that the protein encoded by the POF1 gene, Pof1p, is an ATPase that may be part of the Saccharomyces cerevisiae protein quality control pathway. According to the results, Δpof1 cells showed increased sensitivity to hydrogen peroxide, tert-butyl hydroperoxide, heat shock and protein unfolding agents, such as dithiothreitol and tunicamycin. Besides, the overexpression of POF1 suppressed the sensitivity of Δpct1, a strain that lacks a gene that encodes a phosphocholine cytidylyltransferase, to heat shock. In vitro analysis showed, however, that the purified Pof1p enzyme had no cytidylyltransferase activity but does have ATPase activity, with catalytic efficiency comparable to other ATPases involved in endoplasmic reticulum-associated degradation of proteins (ERAD). Supporting these findings, co-immunoprecipitation experiments showed a physical interaction between Pof1p and Ubc7p (an ubiquitin conjugating enzyme) in vivo.Conclusions
Taken together, the results strongly suggest that the biological function of Pof1p is related to the regulation of protein degradation.4.
Marmoset phylogenetics, conservation perspectives, and evolution of the mtDNA control region 总被引:2,自引:1,他引:2
Tagliaro CH; Schneider MP; Schneider H; Sampaio IC; Stanhope MJ 《Molecular biology and evolution》1997,14(6):674-684
Marmosets (genus Callithrix) are a diverse group of platyrrhine primates
with 13-15 purported taxa, many of them considered endangered.
Morphological analyses constitute most of the basis for recognition of
these forms as distinct taxa. The purpose of this study was to provide a
molecular view, based on mitochondrial control region sequences, of the
evolutionary history of the marmosets, concomitant with a molecular
phylogenetic perspective on species diversity within the group. An
additional purpose was to provide the first comparative examination of a
complete New World monkey control region sequence with those of other
mammals. The phylogenetic analyses provide convincing support for a split
between the Atlantic forest and Amazonian marmosets, with the inclusion of
the pygmy marmoset (Cebuella pygmaea) at the base of the Amazonian clade.
The earliest branch of the Atlantic forest group was C. aurita. In the
Amazonian group, the analyses do not support the recognition of C.
humeralifer and the recently described C mauesi as distinct taxa. They do,
however, support a clear distinction between C. argentata and a strongly
supported mixed clade of C. humeralifer and C. mauesi. In the Atlantic
forest group, the phylogenetic tree suggests mixing between C. penicillata,
C. kuhli, and possibly C. jacchus. Most of the sequence features
characteristic of other mammal control regions were also evident in
marmosets, with the exception that conserved sequence blocks (CSBs) 2 and 3
were not clearly identifiable. Tandem repeat units often associated with
heteroplasmy in a variety of other mammals were not evident in the marmoset
sequences.
相似文献
5.
Background
Glycosyl transferases transfer glycosyl groups onto their substrate. Localization partially defines their function. Glycosyl transferase 25 domain 1 (GLT25D1) was recently shown to have galactosyltransferase activity towards collagens and another well known substrate, mannose binding lectin (MBL). To gain more insight in the role of galactosylation of lysines in the Gly-X-Lys repeats of collagenous proteins, we investigated the subcellular localization of GLT25D1. 相似文献6.
We examined the phylogenetic relationships among five heterothallic species of Neurospora using restriction fragment polymorphisms derived from cosmid probes and sequence data from the upstream regions of two genes, al-1 and frq. Distance, maximum likelihood, and parsimony trees derived from the data support the hypothesis that strains assigned to N. sitophila, N. discreta, and N. tetrasperma form respective monophyletic groups. Strains assigned to N. intermedia and N. crassa, however, did not form two respective monophyletic groups, consistent with a previous suggestion based on analysis of mitochondrial DNAs that N. crassa and N. intermedia may be incompletely resolved sister taxa. Trees derived from restriction fragments and the al-1 sequence position N. tetrasperma as the sister species of N. sitophila. None of the trees produced by our data supported a previous analysis of sequences in the region of the mating type idiomorph that grouped N. crassa and N. sitophila as sister taxa, as well as N. intermedia and N. tetrasperma as sister taxa. Moreover, sequences from al-1, frq, and the mating-type region produced different trees when analyzed separately. The lack of consensus obtained with different sequences could result from the sorting of ancestral polymorphism during speciation or gene flow across species boundaries, or both. 相似文献
7.
In the process of genetic translation, each aminoacyl-tRNA synthetase specifically aminoacylates its cognate tRNAs and rejects the 19 other species of tRNAs. A decrease in the specificity of this reaction can result in misincorporations of amino acids into proteins and be deleterious to the cell. In the case of tyrosyl-tRNA synthetase from Bacillus stearothermophilus, the change of residue Glu152 into Ala results in erroneous interactions with non-cognate tRNAs. To analyse how Glu152 contributes to the discrimination between tRNAs by tyrosyl-tRNA synthetase, 11 changes to this residue were created by mutagenesis. The misaminoacylations of tRNA(Phe) and tRNA(Val) with tyrosine in vitro (on a scale going from 1 to 30) and the toxicity of tyrosyl-tRNA synthetase in vivo (on a scale from 1 to 10(7)) increased in a correlated way when the nature of the side chain in position 152 varied from negatively charged to uncharged then to positively charged. The aminoacylation of tRNA(Tyr) was unaffected by the mutations. The results show that the role of Glu152 in the discrimination between tRNAs is purely negative, that it acts by electrostatic repulsion of non-cognate tRNAs and that this mechanism has been conserved throughout evolution. 相似文献
8.
Lyons C Beharry K Akmal Y Attenello F Nageotte MP 《Prostaglandins & other lipid mediators》2003,70(3-4):317-329
We examined and compared the in vitro effects of misoprostol (synthetic prostaglandin E1 (PGE1) analogue) on prostaglandin E2 (PGE2) secretion and EP3 receptor mRNA expression in the pregnant rat myometrium and cervix at 19 days gestation. Myometrial and cervical tissue samples were exposed to media with or without misoprostol (50 or 100 pg/ml) and incubated for 15 and 30 min, and 1, 3, 6, 12, and 24 h. Media and tissue samples were collected for quantification of PGE2 and mRNA expression of rEP3alpha and rEP3beta receptor, respectively. PGE2 secretion increased (P < or = 0.05) in the myometrium exposed to 50 and 100 pg/ml misoprostol. Cervical PGE2 secretion increased following exposure to the 100 pg/ml dose only. In the myometrium, 50 and 100 pg/ml misoprostol induced elevations in rEP3alpha and rEP3beta receptor mRNA expression. rEP3alpha and rEP3beta receptor mRNA expression in the cervix was not different from controls. These data demonstrate that the EP3 receptor is differentially expressed in the myometrium and cervix in response to misoprostol. This may account for the ability of misoprostol to stimulate the myometrium when administered for cervical ripening. 相似文献
9.
Anonymous nuclear DNA markers in the American oyster and their implications for the heterozygote deficiency phenomenon in marine bivalves 总被引:4,自引:0,他引:4
A puzzling population-genetic phenomenon widely reported in allozyme
surveys of marine bivalves is the occurrence of heterozygote deficits
relative to Hardy-Weinberg expectations. Possible explanations for this
pattern are categorized with respect to whether the effects should be
confined to protein-level assays or are genomically pervasive and expected
to be registered in both protein- and DNA-level assays. Anonymous nuclear
DNA markers from the American oyster were employed to reexamine the
phenomenon. In assays based on the polymerase chain reaction (PCR), two
DNA-level processes were encountered that can lead to artifactual genotypic
scorings: (a) differential amplification of alleles at a target locus and
(b) amplification from multiple paralogous loci. We describe symptoms of
these complications and prescribe methods that should generally help to
ameliorate them. When artifactual scorings at two anonymous DNA loci in the
American oyster were corrected, Hardy-Weinberg deviations registered in
preliminary population assays decreased to nonsignificant values.
Implications of these findings for the heterozygote-deficit phenomenon in
marine bivalves, and for the general development and use of PCR-based
assays, are discussed.
相似文献
10.
Marta Clariano Vanda Marques João Vaz Salma Awam Marta B. Afonso Maria Jesus Perry Cecília MP Rodrigues 《化学与生物多样性》2023,20(3):e202300222
Curcumin has a plethora of biological properties, making this compound potentially effective in the treatment of several diseases, including cancer. However, curcumin clinical use is compromised by its poor pharmacokinetics, being crucial to find novel analogs with better pharmacokinetic and pharmacological properties. Here, we aimed to evaluate the stability, bioavailability and pharmacokinetic profiles of monocarbonyl analogs of curcumin. A small library of monocarbonyl analogs of curcumin 1a–q was synthesized. Lipophilicity and stability in physiological conditions were both assessed by HPLC-UV, while two different methods assessed the electrophilic character of each compound monitored by NMR and by UV-spectroscopy. The potential therapeutic effect of the analogs 1a–q was evaluated in human colon carcinoma cells and toxicity in immortalized hepatocytes. Our results showed that the curcumin analog 1e is a promising agent against colorectal cancer, with improved stability and efficacy/safety profile. 相似文献