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91.
Mariana Malzoni Furtado Solange Maria Gennari Cassia Yumi Ikuta Anah Tereza de Almeida Jácomo Zenaide Maria de Morais Hilda Fátima de Jesus Pena Grasiela Edith de Oliveira Porfírio Leandro Silveira Rahel Sollmann Gisele Oliveira de Souza Natália Mundim T?rres José Soares Ferreira Neto 《PloS one》2015,10(11)
This study investigated the exposure of jaguar populations and domestic animals to smooth Brucella, Leptospira spp. and Toxoplasma gondii in the Cerrado, Pantanal and Amazon biomes of Brazil. Between February 2000 and January 2010, serum samples from 31 jaguars (Panthera onca), 1,245 cattle (Bos taurus), 168 domestic dogs (Canis lupus familiaris) and 29 domestic cats (Felis catus) were collected and analysed by rose bengal test for smooth Brucella, microscopic agglutination test for Leptospira spp. and modified agglutination test for T. gondii. Cattle populations from all sites (9.88%) were exposed to smooth Brucella, but only one jaguar from Cerrado was exposed to this agent. Jaguars captured in the Cerrado (60.0%) and in the Pantanal (45.5%) were seropositive for different serovars of Leptospira spp., cattle (72.18%) and domestic dogs (13.1%) from the three sites and one domestic cat from Pantanal were also seropositive for the agent. The most prevalent serotype of Leptospira spp. identified in jaguars from the Cerrado (Grippotyphosa) and the Pantanal (Pomona) biomes were distinct from those found in the domestic animals sampled. Jaguars (100%), domestic dogs (38.28%) and domestic cats (82.76%) from the three areas were exposed to T. gondii. Our results show that brucellosis and leptospirosis could have been transmitted to jaguars by domestic animals; and jaguars probably play an important role in the maintenance of T. gondii in nature. 相似文献
92.
A novel factor FLOURY ENDOSPERM2 is involved in regulation of rice grain size and starch quality 总被引:6,自引:0,他引:6
She KC Kusano H Koizumi K Yamakawa H Hakata M Imamura T Fukuda M Naito N Tsurumaki Y Yaeshima M Tsuge T Matsumoto K Kudoh M Itoh E Kikuchi S Kishimoto N Yazaki J Ando T Yano M Aoyama T Sasaki T Satoh H Shimada H 《The Plant cell》2010,22(10):3280-3294
Rice (Oryza sativa) endosperm accumulates a massive amount of storage starch and storage proteins during seed development. However, little is known about the regulatory system involved in the production of storage substances. The rice flo2 mutation resulted in reduced grain size and starch quality. Map-based cloning identified FLOURY ENDOSPERM2 (FLO2), a member of a novel gene family conserved in plants, as the gene responsible for the rice flo2 mutation. FLO2 harbors a tetratricopeptide repeat motif, considered to mediate a protein-protein interactions. FLO2 was abundantly expressed in developing seeds coincident with production of storage starch and protein, as well as in leaves, while abundant expression of its homologs was observed only in leaves. The flo2 mutation decreased expression of genes involved in production of storage starch and storage proteins in the endosperm. Differences between cultivars in their responsiveness of FLO2 expression during high-temperature stress indicated that FLO2 may be involved in heat tolerance during seed development. Overexpression of FLO2 enlarged the size of grains significantly. These results suggest that FLO2 plays a pivotal regulatory role in rice grain size and starch quality by affecting storage substance accumulation in the endosperm. 相似文献
93.
Payo IM Ongkana N Tohno S Azuma C Minami T Moriwake Y Tohno Y 《Biological trace element research》2007,119(2):103-110
To elucidate compositional changes of the arteries with aging, the authors investigated age-related changes of elements in
the splenic and pulmonary arteries, which supplied blood to contractile organs. After ordinary dissection by medical students
at Nara Medical University was finished, the splenic and pulmonary arteries were resected from the subjects, ranging in age
from 58 to 94 years. The element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was
found that a moderate accumulation of Ca and P occurred in the splenic artery with aging, but it hardly occurred in the pulmonary
artery with aging. Regarding the relationship among elements, the finding that there were significant direct correlations
among the contents of Ca, P, Mg, and Na was commonly obtained in both the splenic and pulmonary arteries. The accumulation
of Ca and P in the splenic artery with aging occurred independently of that in the pulmonary artery. Histologic observation
indicated that a major part of Ca deposits was seen in the middle tunica, but not in the internal tunica. Therefore, the calcification
occurring in the splenic artery belonged to middle sclerosis. 相似文献
94.
We previously reported that reduced platelet endogenous antioxidant enzymes activities are related to the low plasma zinc
level in patients with end-stage renal failure (ESRF). In this study, we attempt to evaluate whether dietary zinc deprivation
reduces the activities of endogenous antioxidant and then enhances oxidative stress in the unstimulated platelet of normal
and 5/6 nephrectomized (Nx) rats because increased platelet oxidative stress is suggested to involve in the incidence of thrombotic
and atherosclerotic diseases. Male Sprague–Dawley rats (n = 48) were fed a zinc-deficient diet and deionized distilled water for 1 week to induce reduction of plasma zinc level. Half
of the rats continued on this diet for 4 weeks as zinc-deplete group, and the other half were maintained on the same diet
but with zinc-supplemented water (120 mg/L zinc sulfate solution) to correct the reduction of plasma zinc level as zinc-replete
group. Half of each group underwent 5/6 Nx, while the other half underwent sham operation. Another 12 normal rats were fed
standard rat chow (containing 23.4% protein and 50 ppm zinc) and drank deionized distilled water as normal control rats. In
zinc-deplete rats including sham-operated and 5/6 Nx rats exhibited lower endogenous antioxidant enzymes activities such as
reduced glutathione (GSH), superoxide dismutase (SOD), and glutathione peroxidase (GPX) and higher malondialdehyde (MDA) levels
than normal control rats in the unstimulated platelets. However, in zinc-replete rats including sham-operated and 5/6 Nx rats
have a normal endogenous antioxidant enzymes activity and normal MDA levels in the unstimulated platelets. We suggest that
in uremia, the low plasma zinc level may be a risk factor for thrombotic and atherosclerotic diseases because it reduces the
activities of endogenous antioxidant enzymes and increases oxidative stress in the unstimulated platelet.
Supported by grant 92-117 from Taipei Veterans General Hospital 相似文献
95.
Shin Deguchi Yumi Shimazaki Sunao Uozumi Keitaro Tawaraya Hidenori Kawamoto Osamu Tanaka 《Plant and Soil》2007,291(1-2):291-299
A field experiment was conducted to investigate the effects of white clover living mulch on the arbuscular mycorrhizal (AM)
fungus colonization of corn roots and the yield of silage corn. The following seven treatments were setup in a field that
had been kept bare by rotary tillage from August 2003 to July 2004: two white clover living mulch treatments without phosphorus
(P) application, with the white clover shoots clipped and removed or allowed to lie in place before sowing corn; one no-tillage
treatment without P application; and four rotary tillage treatments with different P application rates. White clover was broadcasted
in the living mulch treatments in August 2004. In June 2005, the white clover shoots in the living mulch treatments were clipped.
After tilling the four rotary tillage treatments, corn was sown in all the treatments. The fallow period before sowing corn
was 0 month (living mulch treatments) and 22 months (no-tillage and rotary tillage treatments). At knee high stage, the AM
fungus colonization of the corn roots and the P concentrations of the corn shoots in both the living mulch treatments were
increased relative to those in the other treatments. The yield of corn tended to increase in the no-tillage and rotary tillage
treatments with an increase in the P application rate. On the other hand, the yields of corn in the living mulch treatments
without the P application were not significantly different from the maximum yield among the no-tillage and rotary tillage
treatments. These results suggested that the white clover living mulch increased the yield of corn by facilitating the AM
fungus colonization and improving the P nutrition of corn. 相似文献
96.
The adenovirus vector is very attractive tool not only for the gene therapy but also for the basic sciences. However, because a construction method of this vector had been complex, only limited scientists had constructed and enjoyed the benefits. Recently, various methods were developed and the researchers came to be able to choose an efficient method, which is the COS-TPC method, or a concise procedure, which is the intact-genome transfection method (in vitro ligation method). Here we described not only these methods but also new method to construct the various Ads simultaneously using the recombinase-mediated cassette exchange (RMCE) by the site-specific recombinase. And also we want to refer the possibility to the worth of the vector, especially the vector of the expression-switch. 相似文献
97.
Shi LZ Faith NG Nakayama Y Suresh M Steinberg H Czuprynski CJ 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(10):6952-6962
The aryl hydrocarbon receptor (AhR) is part of a powerful signaling system that is triggered by xenobiotic agents such as polychlorinated hydrocarbons and polycyclic aromatic hydrocarbons. Although activation of the AhR by 2,3,7,8-tetrachlorodibenzo-p-dioxin or certain polycyclic aromatic hydrocarbons can lead to immunosuppression, there is also increasing evidence that the AhR regulates certain normal developmental processes. In this study, we asked whether the AhR plays a role in host resistance using murine listeriosis as an experimental system. Our data clearly demonstrate that AhR null C57BL/6J mice (AhR(-/-)) are more susceptible to listeriosis than AhR heterozygous (AhR(+/-)) littermates when inoculated i.v. with log-phase Listeria monocytogenes. AhR(-/-) mice exhibited greater numbers of CFU of L. monocytogenes in the spleen and liver, and greater histopathological changes in the liver than AhR(+/-) mice. Serum levels of IL-6, MCP-1, IFN-gamma, and TNF-alpha were comparable between L. monocytogenes-infected AhR(-/-) and AhR(+/-) mice. Increased levels of IL-12 and IL-10 were observed in L. monocytogenes-infected AhR(-/-) mice. No significant difference was found between AhR(+/-) and AhR(-/-) macrophages ex vivo with regard to their ability to ingest and inhibit intracellular growth of L. monocytogenes. Intracellular cytokine staining of CD4(+) and CD8(+) splenocytes for IFN-gamma and TNF-alpha revealed comparable T cell-mediated responses in AhR(-/-) and AhR(+/-) mice. Previously infected AhR(-/-) and AhR(+/-) mice both exhibited enhanced resistance to reinfection with L. monocytogenes. These data provide the first evidence that AhR is required for optimal resistance but is not essential for adaptive immune response to L. monocytogenes infection. 相似文献
98.
Nakase T Jindamorakot S Limtong S Am-in S Kawasaki H Imanishi Y Potacharoen W Tanticharoen M 《The Journal of General and Applied Microbiology》2007,53(4):239-245
Two strains of anamorphic yeasts isolated from insect frass collected in southern Thailand were assigned to the genus Candida based on the conventional taxonomic criteria used for yeast classification. In the phylogenetic tree based on the D1/D2 domain of the 26S rDNA, these strains are distant from the known species of yeasts and considered to represent two different new species. They are named Candida kazuoi sp. nov. and Candida hasegawae sp. nov. 相似文献
99.
Novel peroxisomal protease Tysnd1 processes PTS1- and PTS2-containing enzymes involved in beta-oxidation of fatty acids 总被引:1,自引:0,他引:1
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Kurochkin IV Mizuno Y Konagaya A Sakaki Y Schönbach C Okazaki Y 《The EMBO journal》2007,26(3):835-845
Peroxisomes play an important role in beta-oxidation of fatty acids. All peroxisomal matrix proteins are synthesized in the cytosol and post-translationally sorted to the organelle. Two distinct peroxisomal signal targeting sequences (PTSs), the C-terminal PTS1 and the N-terminal PTS2, have been defined. Import of precursor PTS2 proteins into the peroxisomes is accompanied by a proteolytic removal of the N-terminal targeting sequence. Although the PTS1 signal is preserved upon translocation, many PTS1 proteins undergo a highly selective and limited cleavage. Here, we demonstrate that Tysnd1, a previously uncharacterized protein, is responsible both for the removal of the leader peptide from PTS2 proteins and for the specific processing of PTS1 proteins. All of the identified Tysnd1 substrates catalyze peroxisomal beta-oxidation. Tysnd1 itself undergoes processing through the removal of the presumably inhibitory N-terminal fragment. Tysnd1 expression is induced by the proliferator-activated receptor alpha agonist bezafibrate, along with the increase in its substrates. A model is proposed where the Tysnd1-mediated processing of the peroxisomal enzymes promotes their assembly into a supramolecular complex to enhance the rate of beta-oxidation. 相似文献
100.