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111.
Sinzinando Albuquerque-Lima Arthur Domingos-Melo Tarcila C. L. Nadia Elisângela L. S. Bezerra Daniela M. A. F. Navarro Paulo Milet-Pinheiro Isabel C. Machado 《Plant Species Biology》2020,35(3):243-255
'Big Bang' flowering is common among geophyte plants and is a strategy particularly important in arid areas. Griffinia is a genus whose species have very ephemeral flowering. Not surprisingly, there is so far no information on the reproductive biology and pollination ecology of any Griffinia species. Here, we highlight an amazing phenomenon of massive flowering in Griffinia gardneriana, a species that blooms for only one or two nights and emits a remarkable odor plume in the Caatinga night. The flowering event of the species varied depending on the locality, but it was always associated with the rainy season. The high number of white tubular flowers produce a strong sweet perfume dominated by (E)-nerolidol (42%), linalool (33%) and (E)-β-ocimene (15%). Agrius cingulata (Sphingidae) was the only pollinator recorded. Because G. gardneriana set only a few fruits by self-pollination, in contrast to a high number of fruits under natural conditions, this hawkmoth pollination system seems to be very efficient. 相似文献
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Natalia Hernández-Beltrán Carlos B. Moreno Ángela María Gutiérrez-Álvarez 《Endocrinología y nutrición》2013,60(1):25-32
Diabetes is a metabolic disease affecting approximately 300 million people worldwide. Neuropathy is one of its frequent complications, and may affect sensory, motor, and autonomic nerves. Its pathophysiology has not fully been elucidated. Several hypotheses have been proposed, and mitochondria have been suggested to play a significant role. This article reviews the mechanisms involved in mitochondrial dysfunction and development of diabetic neuropathy, consisting mainly of oxidative and inflammatory stress, changes in intracellular calcium regulation, apoptotic processes, and changes in mitochondrial structure and function that may lead to development of diabetic neuropathy. 相似文献
114.
Marta Cruces-Sande Rocío Vila-Bedmar Alba C. Arcones Águeda González-Rodríguez Patricia Rada Virginia Gutiérrez-de-Juan Javier Vargas-Castrillón Paula Iruzubieta Cristina Sánchez-González Laura Formentini Javier Crespo Carmelo García-Monzón María L. Martínez-Chantar Ángela M. Valverde Federico Mayor Cristina Murga 《生物化学与生物物理学报:疾病的分子基础》2018,1864(12):3655-3667
Insulin resistance (IR) and obesity are important risk factors for non-alcoholic fatty liver disease (NAFLD). G protein-coupled receptor kinase 2 (GRK2) is involved in the development of IR and obesity in vivo. However, its possible contribution to NAFLD and/or non-alcoholic steatohepatitis (NASH) independently of its role on IR or fat mass accretion has not been explored. Here, we used wild-type (WT) or GRK2 hemizygous (GRK2±) mice fed a high-fat diet (HFD) or a methionine and choline-deficient diet (MCD) as a model of NASH independent of adiposity and IR. GRK2± mice were protected from HFD-induced NAFLD. Moreover, MCD feeding caused an increased in triglyceride content and liver-to-body weight ratio in WT mice, features that were attenuated in GRK2± mice. According to their NAFLD activity score, MCD-fed GRK2± mice were diagnosed with simple steatosis and not overt NASH. They also showed reduced expression of lipogenic and lipid-uptake markers and less signs of inflammation in the liver. GRK2± mice preserved hepatic protective mechanisms as enhanced autophagy and mitochondrial fusion and biogenesis, together with reduced endoplasmic reticulum stress. GRK2 protein was increased in MCD-fed WT but not in GRK2± mice, and enhanced GRK2 expression potentiated palmitic acid-triggered lipid accumulation in human hepatocytes directly relating GRK2 levels to steatosis. GRK2 protein and mRNA levels were increased in human liver biopsies from simple steatosis or NASH patients in two different human cohorts. Our results describe a functional relationship between GRK2 levels and hepatic lipid accumulation and implicate GRK2 in the establishment and/or development of NASH. 相似文献
115.
Stem radial growth and water storage responses to heat and drought vary between conifers with differing hydraulic strategies 下载免费PDF全文
Àngela Manrique‐Alba Sanna Sevanto Henry D. Adams Adam D. Collins Lee T. Dickman Esteban Chirino Juan Bellot Nate G. McDowell 《Plant, cell & environment》2018,41(8):1926-1934
We investigated stem radial growth and water storage dynamics of 2 conifer species differing in hydraulic carbon strategies, Juniperus monosperma and Pinus edulis, under conditions of ambient, drought (~45% reduction in precipitation), heat (~4.8 °C temperature increase), and the combination of drought + heat, in 2013 and 2014. Juniper maintained low growth across all treatments. Overall, the relatively isohydric piñon pine showed significantly greater growth and water storage recharge than the relatively anisohydric juniper across all treatments in the average climate year (2014) but no differences in the regionally dry year (2013). Piñon pine ceased growth at a constant predawn water potential across all treatments and at a less negative water potential threshold than juniper. Heat has a greater negative impact on piñon pines' growth and water storage than drought, whereas juniper was, in contrast, unaffected by heat but strongly impacted by drought. The whole‐plant hydraulic carbon strategies, in this case captured using the isohydric/anisohydric concept, translate into alternative growth and water storage strategies under drought and heat conditions. 相似文献
116.
Nucleotide and nucleoside involvement in immunomodulation in experimental Chagas disease 总被引:1,自引:0,他引:1
Guilherme M. do Carmo Mariângela F. de Sá Matheus D. Baldissera Thirssa H. Grando Ricardo E. Mendes Valesca V. Cardoso Emerson A. Casali Cesar Eduardo J. Moritz Silvia G. Monteiro Aleksandro S. Da Silva 《Molecular and cellular biochemistry》2018,437(1-2):203-210
Whether the Arg913Gln variation (rs11643718, G/A) of SLC12A3 contributes to diabetic nephropathy (DN) remains controversial. We undertook a case–control study to evaluate the association of the SLC12A3-Arg913Gln variation with the risk of end-stage renal disease (ESRD) in Chinese type 2 diabetes mellitus (T2DM) patients undergoing hemodialysis, and analyzed the genotype–phenotype interaction. Unrelated Chinese T2DM patients (n = 372) with diabetic retinopathy were classified into the non-DN (control) group (n = 151; duration of T2DM >15 years, no signs of renal involvement) and the DN–ESRD group (n = 221; ESRD due to T2DM, receiving hemodialysis). Polymerase chain reaction-direct sequencing was used to genotype the SLC12A3-Arg913Gln variation for all participants. The frequency of the GA+AA genotype in the DN–ESRD group was significantly higher than that of the non-DN group (23.1 vs. 9.9%; adjusted OR 2.2 (95% CI 1.3–4.5), P = 0.019). In the non-DN group, GA+AA carriers had a significantly higher urinary albumin excretion rate (UAER) and diastolic blood pressure compared with GG carriers (both P < 0.05). The SLC12A3-Arg913Gln variation may be associated with increased blood pressure and UAER and, therefore, could be used to predict the development and progression of DN–ESRD in Chinese T2DM patients undergoing hemodialysis. 相似文献
117.
Luz Ángela Galindo-Leva Stephen R. Hughes Juan Carlos López-Núñez Joshua M. Jarodsky Adam Erickson Mitchell R. Lindquist Elby J. Cox Kenneth M. Bischoff Eric C. Hoecker Siqing Liu Nasib Qureshi Marjorie A. Jones 《Journal of industrial microbiology & biotechnology》2016,43(7):927-939
Economically important plants contain large amounts of inulin. Disposal of waste resulting from their processing presents environmental issues. Finding microorganisms capable of converting inulin waste to biofuel and valuable co-products at the processing site would have significant economic and environmental impact. We evaluated the ability of two mutant strains of Kluyveromyces marxianus (Km7 and Km8) to utilize inulin for ethanol production. In glucose medium, both strains consumed all glucose and produced 0.40 g ethanol/g glucose at 24 h. In inulin medium, Km7 exhibited maximum colony forming units (CFU)/mL and produced 0.35 g ethanol/g inulin at 24 h, while Km8 showed maximum CFU/mL and produced 0.02 g ethanol/g inulin at 96 h. At 24 h in inulin + glucose medium, Km7 produced 0.40 g ethanol/g (inulin + glucose) and Km8 produced 0.20 g ethanol/g (inulin + glucose) with maximum CFU/mL for Km8 at 72 h, 40 % of that for Km7 at 36 h. Extracellular inulinase activity at 6 h for both Km7 and Km8 was 3.7 International Units (IU)/mL. 相似文献
118.
Evaluating an unmanned aerial vehicle‐based approach for assessing habitat extent and condition in fine‐scale early successional mountain mosaics 下载免费PDF全文
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120.
Ruberval A. Lopes Cleide de Oliveira Maringela N.M. Campos Sílvio M. Campos Esther G. Birman 《Acta zoologica》1974,55(1):17-24
Morphological and histochemical studies of the cell types in the cephalic glands of Bothrops jararaca have been performed. It is concluded: 1) mucous cells are found in the salivary labial, accessory glands; mucous-serous cells are found in the salivary labial, accessory and Harderian glands; serous-mucous cells are found only in the venom gland; 2) neutral mucosubstances and protein were found in the salivary labial, venom, accessory and Harderian glands; 3) hyaluronic acid was detected in the Harderian gland; 4) of the to sulfated acid mucosubstances, only chondroitin sulfate B was detected in the salivary labial and accessory glands; 5) sialic acid was detected in the salivary labial, accessory and Harderian glands. 相似文献