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961.
Marcia W. Carneiro Diego M. Santos Kiyoshi F. Fukutani Jorge Clarencio Jose Carlos Miranda Claudia Brodskyn Aldina Barral Manoel Barral-Netto Manuel Soto Camila I. de Oliveira 《PloS one》2012,7(12)
Background
Nucleosomal histones are intracellular proteins that are highly conserved among Leishmania species. After parasite destruction or spontaneous lysis, exposure to these proteins elicits a strong host immune response. In the present study, we analyzed the protective capability of Leishmania infantum chagasi nucleosomal histones against L. braziliensis infection using different immunization strategies.Methodology/Principal Findings
BALB/c mice were immunized with either a plasmid DNA cocktail (DNA) containing four Leishmania nucleosomal histones or with the DNA cocktail followed by the corresponding recombinant proteins plus CpG (DNA/Protein). Mice were later challenged with L. braziliensis, in the presence of sand fly saliva. Lesion development, parasite load and the cellular immune response were analyzed five weeks after challenge. Immunization with either DNA alone or with DNA/Protein was able to inhibit lesion development. This finding was highlighted by the absence of infected macrophages in tissue sections. Further, parasite load at the infection site and in the draining lymph nodes was also significantly lower in vaccinated animals. This outcome was associated with increased expression of IFN-γ and down regulation of IL-4 at the infection site.Conclusion
The data presented here demonstrate the potential use of L. infantum chagasi nucleosomal histones as targets for the development of vaccines against infection with L. braziliensis, as shown by the significant inhibition of disease development following a live challenge. 相似文献962.
963.
Kiyoshi Ando Shigeru Obayashi Yuji Nagai Arata Oh-Nishi Takafumi Minamimoto Makoto Higuchi Takashi Inoue Toshio Itoh Tetsuya Suhara 《PloS one》2012,7(10)
Background
Positron Emission Tomography (PET) measurement was applied to the brain of the common marmoset, a small primate species, treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The marmoset shows prominent Parkinson’s disease (PD) signs due to dopaminergic neural degeneration. Recently, the transgenic marmoset (TG) carrying human PD genes is developing. For phenotypic evaluations of TG, non-invasive PET measurement is considered to be substantially significant. As a reference control for TG, the brain of the MPTP-marmoset as an established and valid model was scanned by PET. Behavioral analysis was also performed by recording locomotion of the MPTP-marmoset, as an objective measure of PD signs.Methodology/Principal Findings
Marmosets received several MPTP regimens (single MPTP regimen: 2 mg/kg, s.c., per day for 3 consecutive days) were used for PET measurement and behavioral observation. To measure immobility as a central PD sign, locomotion of marmosets in their individual living cages were recorded daily by infrared sensors. Daily locomotion counts decreased drastically after MPTP regimens and remained diminished for several months or more. PET scan of the brain, using [11C]PE2I as a ligand of the dopamine (DA) transporter, was performed once several months after the last MPTP regimen. The mean binding potential (BPND) in the striatum (putamen and caudate) of the MPTP-marmoset group was significantly lower than that of the MPTP-free control group (n = 5 for each group). In the MPTP-marmosets, the decrease of BPND in the striatum closely correlated with the decrease in locomotion counts (r = 0.98 in putamen and 0.91 in caudate).Conclusion/Significance
The present characterization of neural degeneration using non-invasive PET imaging and of behavioral manifestation in the MPTP marmoset mimics typical PD characteristics and can be useful in evaluating the phenotype of TG marmosets being developed. 相似文献964.
Due to dramatic advances in DNA technology, quantitative measures of annotation data can now be obtained in continuous coordinates across the entire genome, allowing various heterogeneous 'genomic landscapes' to emerge. Although much effort has been devoted to comparing DNA sequences, not much attention has been given to comparing these large quantities of data comprehensively. In this article, we introduce a method for rapidly detecting local regions that show high correlations between genomic landscapes. We overcame the size problem for genome-wide data by converting the data into series of symbols and then carrying out sequence alignment. We also decomposed the oscillation of the landscape data into different frequency bands before analysis, since the real genomic landscape is a mixture of embedded and confounded biological processes working at different scales in the cell nucleus. To verify the usefulness and generality of our method, we applied our approach to well investigated landscapes from the human genome, including several histone modifications. Furthermore, by applying our method to over 20 genomic landscapes in human and 12 in mouse, we found that DNA replication timing and the density of Alu insertions are highly correlated genome-wide in both species, even though the Alu elements have amplified independently in the two genomes. To our knowledge, this is the first method to align genomic landscapes at multiple scales according to their shape. 相似文献
965.
Pietro Kiyoshi Maruyama Clesnan Mendes-Rodrigues Estevão Alves-Silva Amanda Ferreira Cunha 《Flora》2012
Mistletoes constitute an important food resource for animals in many ecosystems. However, these plants are considered pests in urban areas because of deleterious effects they have on the host trees. Studies in urban areas were mostly focused on listing host species or procedures to control the “pest”. In this sense, broader studies including several aspects of mistletoes ecology in urban ecosystems are still missing. We studied the interaction of the mistletoe, Phoradendron affine, with its dispersers and hosts in two urban sites in Uberlândia, Brazil. Phoradendron affine fruits were consumed almost exclusively by Euphonia chlorotica, which was crucial for seed germination. Parasitism was recorded in five hosts, two native (Handroanthus chrysotrichus and Tabebuia roseoalba) and three exotic species (Spathodea campanulata, Ligustrum lucidum and Melia azedarach). Mistletoes were found parasitizing larger host trees, a trend commonly reported for mistletoe-host interaction. Mistletoe seed germination was not affected by the trees species, whether host or non-host, but the radicle of germinated seeds could not penetrate the bark and seedlings invariably died in non-host species. We found a high prevalence of parasitism in our study, in comparison to what previous studies reported for natural areas. The spatial distribution of the hosts and high light incidence on isolated host trees may lead to this high prevalence in urban areas. Rather than eradicated, mistletoes in urban areas should be ecologically managed and their importance for bird species conservation must be considered. More studies to determine which bird species are favoured by mistletoe presence in urban areas will be essential for this purpose. 相似文献
966.
Mitsuhiro Nagata Yasuyuki Miyakoshi Hirokazu Urabe Makoto Fujiwara Yoshitaka Sasaki Kiyoshi Kasugai Mitsuru Torao Daisei Ando Masahide Kaeriyama 《Environmental Biology of Fishes》2012,94(1):311-323
The chum and pink salmon catches in Hokkaido, Japan have increased dramatically since the 1970s and the 1990s, respectively.
In contrast, masu salmon catches have been steadily decreasing. Despite intensive hatchery development in Hokkaido, naturally
spawning salmon populations persist based on results from a recent river survey. This paper focuses on the challenges of maintaining
hatchery salmon populations while protecting natural chum, pink and masu salmon populations in Hokkaido. Two important initiatives
related to meeting this ambitious goal are managing hatcheries in a way that minimizes negative interactions between natural
and hatchery salmon populations, and initiating new efforts at restoring and rehabilitating degraded freshwater habitats.
In addition, in order to maintain a balance of demand and supply in the domestic market through the exportation of extra salmon,
Hokkaido has decided to enter full assessment to gain Marine Stewardship Council (MSC) certification of the Hokkaido chum
salmon trap net fishery. This would involve a fundamental shift in fisheries management as practiced in Japan, specifically
elevating the importance of managing the fishery in a way that conserves natural salmon populations. A key component of a
new salmon management strategy is the establishment of a zone management framework based on the designation of stream units
to spatially separate natural salmon from hatchery salmon to minimize negative effects of hatchery fish and to utilize effectively
hatchery salmon for commercial fisheries. This effort is allied with similar initiatives in other Pacific Rim countries that
are focusing on management reform to restore natural ecosystem function and maintain the coexistence of wild and hatchery
salmon. 相似文献
967.
Yasuyuki Miyakoshi Hirokazu Urabe Hayato Saneyoshi Tomoya Aoyama Hiroyuki Sakamoto Daisei Ando Kiyoshi Kasugai Yoshio Mishima Masayuki Takada Mitsuhiro Nagata 《Environmental Biology of Fishes》2012,94(1):197-206
Since the late 20th century, the biomass of Pacific salmon Oncorhynchus spp. has increased. Hokkaido, northern Japan, is one of the main areas of chum salmon O. keta production in the North Pacific and intensive hatchery programs support the recent high abundance. However, proper management
of naturally spawning populations is necessary to conserve healthy stocks of this species. In 2008, we started a program to
assess the naturally spawning chum salmon populations in Hokkaido. Of the total of approximately 1,500 rivers in Hokkaido,
238 rivers with lengths of longer than 8 km (excluding those rivers used for hatchery broodstock collection) were surveyed
in 2008 and 2009. The number of non-enhanced rivers found to contain naturally reproducing chum salmon was 59 (31.4% of surveyed
rivers) and 50 (37.6% of surveyed rivers) rivers in 2008 and 2009, respectively. Including the rivers where hatchery broodstock
were collected and rivers shorter than 8 km that contain naturally spawning chum salmon, chum salmon ascended at least 191
and 175 rivers in Hokkaido in 2008 and 2009, respectively. Repeated foot surveys indicated that the run timings of naturally
spawning chum salmon may be affected by coastal commercial fisheries. This study showed that naturally spawning chum salmon
remain in many rivers in Hokkaido where hatchery programs have been intensively conducted. 相似文献
968.
969.
Ozawa K Loscha KV Kuppan KV Loh CT Dixon NE Otting G 《Biochemical and biophysical research communications》2012,418(4):652-656
Using aminoacyl-tRNA synthetase/suppressor tRNA pairs derived from Methanocaldococcus jannaschii, an Escherichia coli cell-free protein production system affords proteins with site-specifically incorporated unnatural amino acids (UAAs) in high yields through the use of optimized amber suppressor tRNA(CUA)(opt) and optimization of reagent concentrations. The efficiency of the cell-free system allows the incorporation of trifluoromethyl-phenylalanine using a polyspecific synthetase evolved previously for p-cyano-phenylalanine, and the incorporation of UAAs at two different sites of the same protein without any re-engineering of the E. coli cells used to make the cell-free extract. 相似文献
970.
Ma T Yamada S Ichwan SJ Iseki S Ohtani K Otsu M Ikeda MA 《Biochemical and biophysical research communications》2012,417(3):931-937
The p53 tumor suppressor protein plays key roles in protecting cells from tumorigenesis. Phosphorylation of p53 at Ser46 (p53Ser46) is considered to be a crucial modification regulating p53-mediated apoptosis. Because the activity of p53 is impaired in most human cancers, restoration of wild-type p53 (wt-p53) function by its gene transfer or by p53-reactivating small molecules has been extensively investigated. The p53-reactivating compounds Nutlin-3 and RITA activate p53 in the absence of genotoxic stress by antagonizing the action of its negative regulator Mdm2. Although controversial, Nutlin-3 was shown to induce p53-mediated apoptosis in a manner independent of p53 phosphorylation. Recently, RITA was shown to induce apoptosis by promoting p53Ser46 phosphorylation. Here we examined whether Nutlin-3 or RITA can overcome resistance to p53-mediated apoptosis in p53-resistant tumor cell lines lacking the ability to phosphorylate p53Ser46. We show that Nutlin-3 did not rescue the apoptotic defect of a Ser46 phosphorylation-defective p53 mutant in p53-sensitive tumor cells, and that RITA neither restored p53Ser46 phosphorylation nor induced apoptosis in p53Ser46 phosphorylation-deficient cells retaining wt-p53. Furthermore, treatment with Nutlin-3 or RITA together with adenoviral p53 gene transfer also failed to induce apoptosis in p53Ser46 phosphorylation-deficient cells either expressing or lacking wt-p53. These results indicate that neither Nutlin-3 nor RITA in able to induce p53-mediated apoptosis in the absence of p53Ser46 phosphorylation. Thus, the dysregulation of this phosphorylation in tumor cells may be a critical factor that limits the efficacy of these p53-based cancer therapies. 相似文献