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991.
Ghosh S Paez-Cortez JR Boppidi K Vasconcelos M Roy M Cardoso W Ai X Fine A 《The Journal of biological chemistry》2011,286(25):22678-22687
Notch3 signaling is fundamental for arterial specification of systemic vascular smooth muscle cells (VSMCs). However, the developmental role and signaling properties of the Notch3 receptor in the mouse pulmonary artery remain unknown. Here, we demonstrate that Notch3 is expressed selectively in pulmonary artery VSMCs, is activated from late fetal to early postnatal life, and is required to maintain the morphological characteristics and smooth muscle gene expression profile of the pulmonary artery after birth. Using a conditional knock-out mouse model, we show that Notch3 receptor activation in VSMCs is Jagged1-dependent. In vitro VSMC lentivirus-mediated Jagged1 knockdown, confocal localization analysis, and co-culture experiments revealed that Notch3 activation is cell-autonomous and occurs through the physical engagement of Notch3 and VSMC-derived Jagged1 in the interior of the same cell. Although the current models of mammalian Notch signaling involve a two-cell system composed of a signal-receiving cell that expresses a Notch receptor on its surface and a neighboring signal-sending cell that provides membrane-bound activating ligand, our data suggest that pulmonary artery VSMC Notch3 activation is cell-autonomous. This unique mechanism of Notch activation may play an important role in the maturation of the pulmonary artery during the transition to air breathing. 相似文献
992.
Gambini J Gomez-Cabrera MC Borras C Valles SL Lopez-Grueso R Martinez-Bello VE Herranz D Pallardo FV Tresguerres JA Serrano M Viña J 《Archives of biochemistry and biophysics》2011,(1):2008-29
Sirtuins are deacetylases involved in metabolic regulation and longevity. Our aim was to test the hypothesis that they are subjected to redox regulation by the [NADH]/[NAD+] ratio. We used NIH3T3 fibroblasts in culture, Drosophila fed with or without ethanol and exercising rats. In all three models an increase in [NADH]/[NAD+] came up with an increased expression of sirtuin mRNA and protein. PGC-1α (a substrate of sirtuins) protein level was significantly increased in fibroblasts incubated with lactate and pyruvate but this effect was lost in fibroblasts obtained from sirtuin-deficient mice.We conclude that the expression of sirtuins is subject to tight redox regulation by the [NADH]/[NAD+] ratio, which is a major sensor for metabolite availability conserved from invertebrates to vertebrates. 相似文献
993.
Roc��o Castro-Gonz��lez Lourdes Mart��nez-Aguilar Augusto Ram��rez-Trujillo Paulina Estrada-de los Santos Jes��s Caballero-Mellado 《Plant and Soil》2011,345(1-2):155-169
Sugarcane is an important crop around the world. Burkholderia genus has emerged as an important plant associated bacteria in the last years. In this study, the occurrence of Burkholderia species associated with two sugarcane varieties cultivated in Mexico was assessed. Burkholderia species were isolated with and without diazotrophs enrichment from sugarcane. Burkholderia strains were identified using a semi-selective set of primers and clustered by restriction analysis of 16S rRNA. The isolates were characterized by 16S rRNA, recA and nifH sequence analysis, whole-cell protein patterns, and plant-growth promotion (PGP) characteristics. Diazotrophic B. unamae and B. tropica were predominant using diazotroph enrichment method. Non-diazotrophic B. cepacia complex (Bcc) species were predominant without enrichment. Among non-diazotrophs, B. tropica was identified. The diazotrophic Burkholderia species exhibit in vitro PGP activities: biosynthesis of indolic compounds, phosphate solubilization, siderophores production and acdS gene presence, which encodes the enzyme ACC (1-aminocyclopropane-1-carboxylate) deaminase. The present study confirms the broad environmental and geographic distribution of diazotrophic B. unamae and B. tropica, and reveals the riches of Bcc and other Burkholderia species associated with sugarcane field-grown in Mexico. This work also shows the potential activities in PGP. 相似文献
994.
995.
Jaqueline Soares da Silva Sharlene Lopes Pereira Rodolfo do Couto Maia Sharon Schilling Landgraf Celso Caruso-Neves Arthur Eugen Kümmerle Carlos Alberto Manssour Fraga Eliezer Jesus Barreiro Roberto Takashi Sudo Gisele Zapata-Sudo 《Life sciences》2014
Aims
This work investigated the effects of 3,4-methylenedioxybenzoyl-2-thienylhydrazone (LASSBio-294) treatment on the contractile response of soleus (SOL) muscle from rats submitted to myocardial infarction (MI).Main methods
Following coronary artery ligation, LASSBio-294 (2 mg/kg, i.p.) or vehicle was administrated once daily for 4 weeks.Key findings
The run time to fatigue for sham rats was 17.9 ± 2.6 min, and it was reduced to 3.3 ± 0.8 min (P < 0.05) in MI rats. In MI rats treated with LASSBio-294, the time to fatigue was 15.1 ± 3.6 min. During the contractile test, SOL muscles from sham rats showed a response of 7.12 ± 0.54 N/cm2 at 60 Hz, which was decreased to 5.45 ± 0.49 N/cm2 (P < 0.05) in MI rats. The contractility of SOL muscles from the MI-LASSBio-294 group was increased to 9.01 ± 0.65 N/cm2. At 16 mM caffeine, the contractility was reduced from 2.31 ± 0.33 to 1.60 ± 0.21 N/cm2 (P < 0.05) in the MI group. In SOL muscles from MI-LASSBio-294 rats, the caffeine response was increased to 2.62 ± 0.33 N/cm2. Moreover, SERCA2a expression in SOL muscles was decreased by 0.31-fold (31%) in the MI group compared to the Sham group (P < 0.05). In the MI-LASSBio-294 group, it was increased by 1.53-fold (153%) compared to the MI group (P < 0.05). Meanwhile, the nuclear density in SOL muscles was increased in the MI group compared to the Sham group. Treatment with LASSBio-294 prevented this enhancement of cellular infiltrate.Significance
LASSBio-294 treatment prevented the development of muscular fatigue and improved exercise intolerance in rats submitted to MI. 相似文献996.
Silvia Garagna Jesus Page Raul Fernandez-Donoso Maurizio Zuccotti Jeremy B. Searle 《Chromosoma》2014,123(6):529-544
Many different chromosomal races with reduced chromosome number due to the presence of Robertsonian fusion metacentrics have been described in western Europe and northern Africa, within the distribution area of the western house mouse Mus musculus domesticus. This subspecies of house mouse has become the ideal model for studies to elucidate the processes of chromosome mutation and fixation that lead to the formation of chromosomal races and for studies on the impact of chromosome heterozygosities on reproductive isolation and speciation. In this review, we briefly describe the history of the discovery of the first and subsequent metacentric races in house mice; then, we focus on the molecular composition of the centromeric regions involved in chromosome fusion to examine the molecular characteristics that may explain the great variability of the karyotype that house mice show. The influence that metacentrics exert on the nuclear architecture of the male meiocytes and the consequences on meiotic progression are described to illustrate the impact that chromosomal heterozygosities exert on fertility of house mice—of relevance to reproductive isolation and speciation. The evolutionary significance of the Robertsonian phenomenon in the house mouse is discussed in the final section of this review. 相似文献
997.
Leônidas L. Belan Edson A. Pozza Marcelo L. de O. Freitas Ricardo M. de Souza Waldir C. de Jesus Junior Júlia M. Oliveira 《Journal of Phytopathology》2014,162(11-12):801-810
Due to the lack of a standardized visual method for assessing bacterial blight (Pseudomonas syringae pv. garcae) in coffee leaves, a diagrammatic scale was developed and validated to quantify the disease. Leaves were collected in crops and nursery with different intensity of symptoms, and the true severity was determined electronically. Based on the frequency distribution of severity values and according to the Weber–Fechner's law of visual stimulus, the minimum and maximum limits and the intermediate levels in the scale were determined. Validation was performed by ten evaluators who estimated the severity of 50 leaves with different intensity of symptoms. One evaluation was performed without diagrammatic scale and two evaluations with the scale at 7‐day intervals. The accuracy, precision, repeatability and reproducibility of the estimates were evaluated. The scale had nine levels: 0 (0%), 1 (0.1–0.99%), 2 (1–2%), 3 (2.01–4%), 4 (4.01–8%), 5 (8.01–16%), 6 (16.01–25%), 7 (25.01–45%) and 8 (≥45.1%). Using the scale, the evaluators were able to improve accuracy, precision, reproducibility and repeatability of estimates, compared to evaluators without scale. The scale was appropriate to visual estimation of severity of bacterial blight in coffee leaves. 相似文献
998.
Gabriel Moura Mascarin Nilce Naomi Kobori Rayan Carlos de Jesus Vital Mark Alan Jackson Eliane Dias Quintela 《World journal of microbiology & biotechnology》2014,30(5):1583-1590
We investigated the potential production and desiccation tolerance of microsclerotia (MS) by Brazilian strains of Metarhizium anisopliae (Ma), M. acridum (Mc) and M. robertsii (Mr). These fungi were grown in a liquid medium containing 16 g carbon l?1 with a carbon:nitrogen ratio of 50:1. One hundred milliliters cultures were grown in 250 ml Erlenmeyer flasks in a rotary incubator shaker at 28 °C and 200 rpm for 5 days. Five-day-old MS were harvested, mixed with diatomaceous earth (DE) and air-dried for 2 days at 30 °C. The air-dried MS–DE granular preparations were milled by mortar + pestle and stored in centrifuged tubes at either 26 or ?20 °C. Desiccation tolerance and conidia production were assessed for dried MS granules by measuring hyphal germination after incubation for 2 days on water agar plates at 26 °C and for conidia production following 7 days incubation. Yields of MS by all strains of Metarhizium were 6.1–7.3 × 106 l?1 after 3 days growth with maximum MS yields (0.7–1.1 × 107 l?1) after 5 days growth. No differences in biomass accumulation were observed after 3 days growth, whereas Ma-CG168 showed the highest biomass accumulation after 5 days growth. Dried MS–DE preparations of all fungal strains were equally tolerant to desiccation (≥93 % germination) and the highest conidia production was obtained by MS granules of Mc-CG423 (4 × 109 conidia g?1). All MS granules showed similar stability after storage at either 26 or ?20 °C for 3.5 months. 相似文献
999.
Cynthia Fernandes Pinto da Luz Denise de Campos Bicudo Sandra Costa-Böddeker Paulo Eduardo de Oliveira Tatiane Araujo de Jesus Ana Luiza Spadano Albuquerque 《Biodiversity and Conservation》2014,23(3):683-696
We performed pollen analyses based on a geochronological scale and historical records in core samples from Lago das Garças Lake in the Fontes do Ipiranga State Park Biological Reserve, in the municipality of São Paulo, Brazil, to evaluate the natural regeneration processes of the Atlantic Forest in an urban area. The stratigraphy of the pollen assemblies showed temporal variations corroborating historical data on anthropogenic interventions in the region, demonstrating the interrelation of richness and the occurrence of sedimented palynomorphs according to the natural successional stages of the vegetation and anthropogenically modified environmental conditions. By integrating palynological, lithological, and geochronological results with historical references we gained a better understanding of the biological evidence for vegetation succession that could be used in recovery programs of degraded urban areas containing Atlantic Forest remnants. 相似文献
1000.