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171.
Angela M. Zanata Willian M. Ohara Osvaldo T. Oyakawa Fernando C. P. Dagosta 《Journal of fish biology》2020,97(5):1343-1353
Characidium iaquira, a new species from the upper rio Juruena, rio Tapajós basin, Brazil, is described. The new species can be promptly distinguished from all congeners by having a unique v-shaped dark mark lying along the caudal-fin extension, in medium- and large-sized specimens, and a remarkable iridescent green colouration in life. Characidium iaquira is closely related to Characidium crandellii and Characidium declivirostre by sharing unambiguous synapomorphies such as branchiostegal membranes united to each other across the isthmus, a scaleless area extending from the isthmus to the pectoral girdle, and dermal flaps surrounding anterior and posterior naris independent, but touching each other distally. Morphological specializations of the paired fins in the three riffle-dwellers species are discussed, including the wing-like shape, robustness, and inclination of the pectoral fin. 相似文献
172.
Jens Amendt Angela Zissler Lena Lutz Ildikò Szelecz Antje Habermann Stefan Pittner 《当今生物学》2020,50(1):58-64
Mulitdisciplinarity in forensics Estimating the time of death is an important task in forensic science. After 1–2 days, however, it is drastically complicated due to autolysis and decay of the body. Here, a combination of established and new methods from different disciplines can help. Morphological changes of the corpse are dependent on the post mortem interval (PMI) and can be classified using scoring systems: The age determination and analysis of species diversity of necrophagous insects developing on the corpse allows the colonisation time determined to the day, the degradation of proteins of skeletal muscles follows a characteristic, time-dependent degradation pattern, soil organisms underneath a decomposing body can be negatively affected by corpse fluids or benefit from the associated input of nutrients such as proteins, lipids and carbohydrates. The combined, interdisciplinary evaluation of all these parameters offers completely new possibilities for the determination of the PMI, even days, weeks and months after death. 相似文献
173.
Elvis Asare-Bediako Julie E. Jones Angela J. Hambidge Mark Stevens Andrew Mead Carol E. Jenner John A. Walsh 《The Annals of applied biology》2020,176(3):130-137
Turnip yellows virus (TuYV) is the most important virus infecting oilseed rape in the United Kingdom. The incidence and spatial distribution of TuYV in winter oilseed rape (WOSR) crops in three regions of England were determined over three growing seasons. Leaf samples were collected from three fields in each region, in autumn (November–December) and spring (April) of the three crop seasons and tested for virus presence by enzyme-linked immunosorbent assay. Infection was detected in all fields except one. Higher TuYV incidences were recorded in 2007–2008 (≤89%) and 2009–2010 (≤100%) crop seasons than in 2008–2009 (≤24%). Highest incidences were recorded in Lincolnshire (≤100%), followed by Warwickshire (≤88%), with lowest incidences in Yorkshire (1–74%). There was a significant increase in incidence detected between autumn and spring sampling in eight fields, a significant decrease in one field and no significant change in 18 fields. Rothamsted Insect Survey suction trap data for the aphid Myzus persicae in Lincolnshire, Warwickshire and Yorkshire revealed two peaks of flight activity in most years (2007–2009). The second peak (September–November) coincided with emergence of WOSR. The highest cumulative (August–November) trap catches in the three regions during the three crop seasons occurred in Lincolnshire and the lowest in Yorkshire; catches in autumn 2009 were highest and lowest in autumn 2008. Regression analysis revealed a highly significant association between the cumulative numbers of M. persicae caught in the suction traps closest to the crops between August and November each year and the incidence of TuYV detected in the WOSR crops in the autumn of each year. Results are discussed in the light of factors affecting the spread of TuYV and future possibilities for control. 相似文献
174.
Atanas G. Atanasov Jian N. Wang Shi P. Gu Jing Bu Matthias P. Kramer Lisa Baumgartner Nanang Fakhrudin Angela Ladurner Clemens Malainer Anna Vuorinen Stefan M. Noha Stefan Schwaiger Judith M. Rollinger Daniela Schuster Hermann Stuppner Verena M. Dirsch Elke H. Heiss 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Peroxisome proliferator-activated receptor gamma (PPARγ) agonists are clinically used to counteract hyperglycemia. However, so far experienced unwanted side effects, such as weight gain, promote the search for new PPARγ activators.Methods
We used a combination of in silico, in vitro, cell-based and in vivo models to identify and validate natural products as promising leads for partial novel PPARγ agonists.Results
The natural product honokiol from the traditional Chinese herbal drug Magnolia bark was in silico predicted to bind into the PPARγ ligand binding pocket as dimer. Honokiol indeed directly bound to purified PPARγ ligand-binding domain (LBD) and acted as partial agonist in a PPARγ-mediated luciferase reporter assay. Honokiol was then directly compared to the clinically used full agonist pioglitazone with regard to stimulation of glucose uptake in adipocytes as well as adipogenic differentiation in 3T3-L1 pre-adipocytes and mouse embryonic fibroblasts. While honokiol stimulated basal glucose uptake to a similar extent as pioglitazone, it did not induce adipogenesis in contrast to pioglitazone. In diabetic KKAy mice oral application of honokiol prevented hyperglycemia and suppressed weight gain.Conclusion
We identified honokiol as a partial non-adipogenic PPARγ agonist in vitro which prevented hyperglycemia and weight gain in vivo.General significance
This observed activity profile suggests honokiol as promising new pharmaceutical lead or dietary supplement to combat metabolic disease, and provides a molecular explanation for the use of Magnolia in traditional medicine. 相似文献175.
Gerda Neubert Katja von Au Katrin Drossel Andreas Tzschach Denise Horn Renate Nickel Angela M. Kaindl 《Gene》2013
Angelman syndrome is a neurodevelopmental disorder characterized by mental retardation, severe speech disorder, facial dysmorphism, secondary microcephaly, ataxia, seizures, and abnormal behaviors such as easily provoked laughter. It is most frequently caused by a de novo maternal deletion of chromosome 15q11–q13 (about 70–90%), but can also be caused by paternal uniparental disomy of chromosome 15q11–q13 (3–7%), an imprinting defect (2–4%) or in mutations in the ubiquitin protein ligase E3A gene UBE3A mostly leading to frame shift mutation. In addition, for patients with overlapping clinical features (Angelman-like syndrome), mutations in methyl-CpG binding protein 2 gene MECP2 and cyclin-dependent kinase-like 5 gene CDKL5 as well as a microdeletion of 2q23.1 including the methyl-CpG binding domain protein 5 gene MBD5 have been described. Here, we describe a patient who carries a de novo 5 Mb-deletion of chromosome 15q11.2–q13.1 known to be associated with Angelman syndrome and a further, maternally inherited deletion 2q21.3 (~ 364 kb) of unknown significance. In addition to classic features of Angelman syndrome, she presented with severe infections in the first year of life, a symptom that has not been described in patients with Angelman syndrome. The 15q11.2–q13.1 deletion contains genes critical for Prader–Willi syndrome, the Angelman syndrome causing genes UBE3A and ATP10A/C, and several non-imprinted genes: GABRB3 and GABRA5 (both encoding subunits of GABA A receptor), GOLGA6L2, HERC2 and OCA2 (associated with oculocutaneous albinism II). The deletion 2q21.3 includes exons of the genes RAB3GAP1 (associated with Warburg Micro syndrome) and ZRANB3 (not disease-associated). Despite the normal phenotype of the mother, the relevance of the 2q21.3 microdeletion for the phenotype of the patient cannot be excluded, and further case reports will need to address this point. 相似文献
176.
Juan D. Toledo Horacio A. Garda Laura V. Cabaleiro Angela Cuellar Magali Pellon-Maison Maria R. Gonzalez-Baro Marina C. Gonzalez 《Molecular and cellular biochemistry》2013,377(1-2):197-205
Reverse cholesterol transport is a process of high antiatherogenic relevance in which apolipoprotein AI (apoA-I) plays an important role. The interaction of apoA-I with peripheral cells produces through mechanisms that are still poorly understood the mobilization of intracellular cholesterol depots toward plasma membrane. In macrophages, these mechanisms seem to be related to the modulation of the activity of acyl-CoA cholesterol acyltransferase (ACAT), the enzyme responsible for the intracellular cholesterol ester biosynthesis that is stored in lipid droplets. The activation of ACAT and the accumulation of lipid droplets play a key role in the transformation of macrophages into foam cells, leading to the formation of atheroma or atherosclerotic plaque. ApoA-I Helsinki (or ?K107) is a natural apoA-I variant with a lysine deletion in the central protein region, carriers of which have increased atherosclerosis risk. We herein show that treatment of cultured RAW macrophages or CHOK1 cells with ?K107, but not with wild-type apoA-I or a variant containing a similar deletion at the C-terminal region (?K226), lead to a marked increase (more than 10 times) in the intracellular ACAT1 protein level as detected by western blot analysis. However, we could only detect a slight increase in cholesteryl ester produced by ?K107 mainly when Chol loading was supplied by low-density lipoprotein (LDL). Although a similar choline-phospholipid efflux is evoked by these apoA-I variants, the change in phosphatidylcholine/sphyngomyelin distribution produced by wild-type apoA-I is not observed with either ?K107 or ?K226. 相似文献
177.
178.
Giuseppe Ferrara Andrea Mazzeo Angela Maria Stella Matarrese Carmela Pacucci Andrea Pacifico Giuseppe Gambacorta Michele Faccia Antonio Trani Vito Gallo Isabella Cafagna Piero Mastrorilli 《Journal of Plant Growth Regulation》2013,32(3):491-505
‘Crimson Seedless’ is a table grape cultivar that often fails to develop adequate red color in Mediterranean climates. Application of abscisic acid (S-ABA) may be an aid for improving color, but its potential effects on overall quality and S-ABA concentration of the berry should be also considered. We tested two concentrations (200 and 400 mg/L) and different times of application (from 1 week after veraison up to 9 days before harvest) of a commercial formulation of S-ABA (ProTone®) to verify the effect on harvestable bunches, color, chemical characteristics, metabolic profile, and S-ABA concentration in the berry. It was found that either the application of S-ABA at 400 mg/L one week after veraison or the application of S-ABA at 400 mg/L one week and four weeks after veraison positively affected the berry skin color, shifting the hue (h°) from 20 to a more red-violet hue (h° = 11–12). In general, the application of S-ABA, with the exception of the late treatments, enhanced coloration of the berries and increased the amount of harvestable bunches at the first pick because it promoted the skin-coloring process. S-ABA did not affect berry firmness but reduced the berry detachment force. Nevertheless, the values remained sufficiently high and the general quality of the bunch was not compromised. Ripening parameters (°Brix, pH, titratable acidity) were not affected by S-ABA applications, and even the primary metabolite profile was not influenced by the treatments as ascertained by multivariate statistical analyses [principal component analyses (PCA) and partial least squares discriminant analysis (PLS-DA)] applied to nuclear magnetic resonance (NMR) data. The S-ABA concentration in the berry, when treatments were performed around veraison, was within the natural range for grape (10–400 ng/g f.w.), whereas when late treatments were applied (few days before harvest), the concentration was higher (more than 1,000 ng/g f.w.). The best results for yield, quality, and S-ABA concentration in the berry were observed for the treatments performed a few days after veraison at the dose of 400 mg/L. This study gives new information about the positive effects of S-ABA on color without any particular change in the metabolic profile of the berry. 相似文献
179.
180.
Genevieve G. A. Fouda Joshua D. Amos Andrew B. Wilks Justin Pollara Caroline A. Ray Anjali Chand Erika L. Kunz Brooke E. Liebl Kaylan Whitaker Angela Carville Shannon Smith Lisa Colvin David J. Pickup Herman F. Staats Glenn Overman Krissey Eutsey-Lloyd Robert Parks Haiyan Chen Celia LaBranche Susan Barnett Georgia D. Tomaras Guido Ferrari David C. Montefiori Hua-Xin Liao Norman L. Letvin Barton F. Haynes Sallie R. Permar 《Journal of virology》2013,87(12):6986-6999
We previously demonstrated that vaccination of lactating rhesus monkeys with a DNA prime/vector boost strategy induces strong T-cell responses but limited envelope (Env)-specific humoral responses in breast milk. To improve vaccine-elicited antibody responses in milk, hormone-induced lactating rhesus monkeys were vaccinated with a transmitted/founder (T/F) HIV Env immunogen in a prime-boost strategy modeled after the moderately protective RV144 HIV vaccine. Lactating rhesus monkeys were intramuscularly primed with either recombinant DNA (n = 4) or modified vaccinia virus Ankara (MVA) poxvirus vector (n = 4) expressing the T/F HIV Env C.1086 and then boosted twice intramuscularly with C.1086 gp120 and the adjuvant MF59. The vaccines induced Env-binding IgG and IgA as well as neutralizing and antibody-dependent cellular cytotoxicity (ADCC) responses in plasma and milk of most vaccinated animals. Importantly, plasma neutralization titers against clade C HIV variants MW965 (P = 0.03) and CAP45 (P = 0.04) were significantly higher in MVA-primed than in DNA-primed animals. The superior systemic prime-boost regimen was then compared to a mucosal-boost regimen, in which animals were boosted twice intranasally with C.1086 gp120 and the TLR 7/8 agonist R848 following the same systemic prime. While the systemic and mucosal vaccine regimens elicited comparable levels of Env-binding IgG antibodies, mucosal immunization induced significantly stronger Env-binding IgA responses in milk (P = 0.03). However, the mucosal regimen was not as potent at inducing functional IgG responses. This study shows that systemic MVA prime followed by either intranasal or systemic protein boosts can elicit strong humoral responses in breast milk and may be a useful strategy to interrupt postnatal HIV-1 transmission. 相似文献