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排序方式: 共有140条查询结果,搜索用时 31 毫秒
41.
Claribel Cruz-García Alison E Murray Jorge LM Rodrigues Jeffrey A Gralnick Lee Ann McCue Margaret F Romine Frank E Löffler James M Tiedje 《BMC microbiology》2011,11(1):64
Background
EtrA in Shewanella oneidensis MR-1, a model organism for study of adaptation to varied redox niches, shares 73.6% and 50.8% amino acid sequence identity with the oxygen-sensing regulators Fnr in E. coli and Anr in Pseudomonas aeruginosa, respectively; however, its regulatory role of anaerobic metabolism in Shewanella spp. is complex and not well understood. 相似文献42.
Carlos G PinheiroJr Eduardo LM Naves Pierre Pino Etienne Losson Adriano O Andrade Guy Bourhis 《Biomedical engineering online》2011,10(1):31
We have now sufficient evidence that using electrical biosignals in the field of Alternative and Augmented Communication is
feasible. Additionally, they are particularly suitable in the case of people with severe motor impairment, e.g. people with
high-level spinal cord injury or with locked-up syndrome. Developing solutions for them implies that we find ways to use sensors
that fit the user's needs and limitations, which in turn impacts the specifications of the system translating the user's intentions
into commands. After devising solutions for a given user or profile, the system should be evaluated with an appropriate method,
allowing a comparison with other solutions. This paper submits a review of the way three bioelectrical signals - electromyographic,
electrooculographic and electroencephalographic - have been utilised in alternative communication with patients suffering
severe motor restrictions. It also offers a comparative study of the various methods applied to measure the performance of
AAC systems. 相似文献
43.
Germán Mariano Gasparini Sergio Gabriel Rodriguez Leopoldo Héctor Soibelzon Elisa Beilinson Esteban Soibelzon Rafaela Velloso Missagia 《Historical Biology》2013,25(6):785-800
Tayassu pecari is widely distributed across the Neotropical region, from northern Argentina to south-eastern Mexico. However, its fossil record is scarce; it is recorded since the middle Pleistocene to Holocene in Argentina, Brazil and Uruguay. This paper aims to: (1) update the systematic synonymy of this species; (2) review and update its geographic chronologic distribution and provide a new Lujanian record of Tayassu pecari in Buenos Aires Province and (3) discuss the paleoenvironmental and paleobiogeographical implications of this record. Considering the quantitative analysis performed, the fossil here recorded clearly integrates the group of Tayassu pecari. This specimen corresponds to the first record of Tayassu pecari in the central-northern region of the Buenos Aires Province. During Late Pleistocene, Tayassu pecari was distributed southern to its recent range, probably evidencing different paleoenvironment conditions. This species is the better adapted peccary to tropical and subtropical rainforests, but may also be present in arid environments. Consequently, Tayassu by itself is insufficient to infer the prevailing environmental conditions. However, according to the fauna associated with the specimen described here, it is possible to infer an open or semi-open and arid or semi-arid environment for the central-northern Buenos Aires region by Late Pleistocene times. 相似文献
44.
45.
Gustavo A. Santos Vinícius D. Pereira Erika A. F. R. Roman Leticia Ignacio-Souza Daniele C. Vitorino Rodrigo Ferreira de Moura Daniela S. Razolli Adriana S. Torsoni Licio A. Velloso Marcio A. Torsoni 《PloS one》2013,8(4)
Background
Hypothalamic AMPK acts as a cell energy sensor and can modulate food intake, glucose homeostasis, and fatty acid biosynthesis. Intrahypothalamic fatty acid injection is known to suppress liver glucose production, mainly by activation of hypothalamic ATP-sensitive potassium (K(ATP)) channels. Since all models employed seem to involve malonyl-CoA biosynthesis, we hypothesized that acetyl-CoA carboxylase can modulate the counter-regulatory response independent of nutrient availability.Methodology/Principal Findings
In this study employing immunoblot, real-time PCR, ELISA, and biochemical measurements, we showed that reduction of the hypothalamic expression of acetyl-CoA carboxylase by antisense oligonucleotide after intraventricular injection increased food intake and NPY mRNA, and diminished the expression of CART, CRH, and TRH mRNA. Additionally, as in fasted rats, in antisense oligonucleotide-treated rats, serum glucagon and ketone bodies increased, while the levels of serum insulin and hepatic glycogen diminished. The reduction of hypothalamic acetyl-CoA carboxylase also increased PEPCK expression, AMPK phosphorylation, and glucose production in the liver. Interestingly, these effects were observed without modification of hypothalamic AMPK phosphorylation.Conclusion/Significance
Hypothalamic ACC inhibition can activate hepatic counter-regulatory response independent of hypothalamic AMPK activation. 相似文献46.
Daniel Andrade Cunha Mônica C. de Alves Luiz Fabrizio Stoppiglia Angélica Gobbi Jorge Carolina Maria Módulo Everardo M. Carneiro Antonio C. Boschero Mário J.A. Saad Lício A. Velloso Eduardo M. Rocha 《Biochimica et Biophysica Acta (BBA)/General Subjects》2007
Previous work has revealed that insulin is secreted in the tear film; its mRNA is expressed in the lachrymal gland (LG) and its receptor in tissues of the ocular surface. To test the hypothesis of insulin production in the LG, we compared normal and diabetic rats for: (1) the presence of insulin and C-peptide, (2) glucose- and carbachol-induced insulin secretion ex-vivo, and (3) biochemical and histological characteristics of diabetic LG that would support this possibility. Four weeks after streptozotocin injection, blood and tears were collected from streptozotocin-diabetic male Wistar rats. Insulin levels in the tear film rose after glucose stimulation in diabetic rats, but remained unchanged in the blood. Ex vivo static secretion assays demonstrated that higher glucose and 200 μM carbachol significantly increased mean insulin levels from LG samples of both groups. Insulin and C-peptide were expressed in LG of diabetic rats as determined by RIA. Comparable synaptophysin immune staining and peroxidase activity in the LG of both groups suggest that the structure and function of these tissues were maintained. These findings provide evidence of insulin production by LG. Higher expression of reactive oxygen species scavengers may prevent oxidative damage to LG compared to pancreatic beta-cells. 相似文献
47.
Bruna Alicia Rafael de Paiva Adriane Wendland Maurício Rossato Marisa A. da S. Velloso Ferreira 《Journal of Phytopathology》2022,170(1):1-14
Common bacterial blight (CBB) is caused by four genetic lineages belonging to two species of Xanthomonas, namely Xanthomonas citri pv. fuscans (includes fuscans, NF2 and NF3 lineages) and X. phaseoli pv. phaseoli (lineage NF1). A collection of 117 strains of Xanthomonas isolated from common bean plants grown in several producing regions of Brazil, between 2007 and 2016 was established. For species and lineage identification, the following tests were performed: multiplex PCR with a set of four specific primer pairs, pathogenicity tests on susceptible cultivar BRS Artico and phylogenetic analysis based on housekeeping gene sequences. The presence of the two species were confirmed among the 117 strains, being 62 non-fuscans strains (NF1, NF2 and NF3) and 55 fuscans strains of X. citri pv. fuscans. To select a set of representative strains for the virulence assay, a PCR-based analysis of effector diversity was performed with 42 strains belonging to the two species. PCR with primers for xopL, avrBsT, xopE2 and xopE1 genes were positive for all strains, while for the other six effectors there was variation. Six distinct effector profiles were detected, and one strain representing each type was inoculated in 15 common bean cultivars with varying levels of resistance to CBB. The fuscans strains showed uniformity in their effector profiles and were the most virulent. The phylogenetic analyses of our strain collection revealed that all genetic variants of CBB pathogens (NF1, NF2, NF3 and fuscans) are present in Brazil, with significant variability in virulence to common bean cultivars. 相似文献
48.
Hernández Pérez A E Cerna Chávez JC Delgado Ortiz M Beltrán Beache LM Tapia Vargas YM Ochoa Fuentes 《Phyton》2019,88(1):11-13
Mexico is the main producer, consumer and exporter
of avocado in the world, being Michoacan the main producer state
contributing more than 80% of the national production. There
are phytopathogens that decimate the production causing the
death of the tree. Root samples were collected in avocado trees
that showed the characteristic symptomatology of the disease
known as avocado sadness, the sampling was carried out in four
of the main avocado producing towns, in the state of Michoacan,
Mexico. The isolation consisted in sowing root tissue in Petri
dishes with V8®-PARPH culture medium, subsequently they were
identified morphologically and for species level it was determined
by molecular biology, with the PCR-ITS technique. Pathogenicity
tests were performed in triplicate with avocado seedlings with more
than six leaves. After 24 hours, the inoculated plants expressed
decay in the apical part, after 120 hours the leaves showed yellowing
and after 15 days there was a generalized wilt on the stem and
leaves, re-isolating the phytopathogen Phytopythium vexans.
This study confirms the first report of the oomycete P. vexans
affecting avocado trees in the most important producing region of
the Mexican Republic. 相似文献
49.
50.
Raquel F. Leal Cláudio S. R. Coy Lício A. Velloso Sushila Dalal Mariana Portovedo Viviane S. Rodrigues Andressa Coope Maria L. S. Ayrizono Jo?o J. Fagundes Marciane Milanski 《Cell and tissue research》2012,350(3):549-552
Crohn??s disease (CD) is a chronic intestinal disease with a multifactorial etiology. Recently, a role for mesenteric fat has been proposed in CD pathophysiology, since fat hypertrophy is detected close to the affected intestinal area; however, there are few studies regarding autophagy and the hypertrophied mesenteric tissue in CD. To evaluate autophagy-related proteins in intestinal mucosae and mesenteric fat of patients with CD and controls, patients with ileocecal CD (CD Group) and with non-inflammatory disease (FC Group) selected for surgery were studied. Expression of LC3-II was determined by immunoblotting of protein extracts. In addition, beclin-1, LC3 and Atg16-L1 RNA levels were measured using RT-PCR. The expression of LC3-II was significantly lower in the mesenteric tissue and higher in intestinal mucosae of CD when compared to controls. However, mRNA expression of autophagy-related proteins was similar when comparing the mesenteric fat groups. These findings suggest a defect in autophagy activation in the mesenteric fat tissue of CD individuals, which could be involved in the maintenance of the inflammatory process. 相似文献