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91.
92.
Paula M. Nogueira Rafael R. Assis Ana C. Torrecilhas Elvira M. Saraiva Natália L. Pessoa Marco A. Campos Eric F. Marialva Cláudia M. Ríos-Velasquez Felipe A. Pessoa Nágila F. Secundino Jer?nimo N. Rugani Elsa Nieves Salvatore J. Turco Maria N. Melo Rodrigo P. Soares 《PLoS neglected tropical diseases》2016,10(8)
The immunomodulatory properties of lipophosphoglycans (LPG) from New World species of Leishmania have been assessed in Leishmania infantum and Leishmania braziliensis, the causative agents of visceral and cutaneous leishmaniasis, respectively. This glycoconjugate is highly polymorphic among species with variation in sugars that branch off the conserved Gal(β1,4)Man(α1)-PO4 backbone of repeat units. Here, the immunomodulatory activity of LPGs from Leishmania amazonensis, the causative agent of diffuse cutaneous leishmaniasis, was evaluated in two strains from Brazil. One strain (PH8) was originally isolated from the sand fly and the other (Josefa) was isolated from a human case. The ability of purified LPGs from both strains was investigated during in vitro interaction with peritoneal murine macrophages and CHO cells and in vivo infection with Lutzomyia migonei. In peritoneal murine macrophages, the LPGs from both strains activated TLR4. Both LPGs equally activate MAPKs and the NF-κB inhibitor p-IκBα, but were not able to translocate NF-κB. In vivo experiments with sand flies showed that both stains were able to sustain infection in L. migonei. A preliminary biochemical analysis indicates intraspecies variation in the LPG sugar moieties. However, they did not result in different activation profiles of the innate immune system. Also those polymorphisms did not affect infectivity to the sand fly. 相似文献
93.
Long‐term effects of the transient COD concentration on the performance of microbial fuel cells 下载免费PDF全文
S. Mateo A. Gonzalez del Campo J. Lobato M. Rodrigo P. Cañizares F.J. Fernandez‐Morales 《Biotechnology progress》2016,32(4):883-890
In this work, the long‐term effects of transient chemical oxygen demands (COD) concentrations over the performance of a microbial fuel cell were studied. From the obtained results, it was observed that the repetitive change in the COD loading rate during 12 h conditioned the behavior of the system during periods of up to 7 days. The main modifications were the enhancement of the COD consumption rate and the exerted current. These enhancements yielded increasing Coulombic efficiencies (CEs) when working with COD concentrations of 300 mg/L, but constant CEs when working with COD concentrations from 900 to 1800 mg/L. This effect could be explained by the higher affinity for the substrate of Geobacter than that of the nonelectrogenic organisms such as Clostridia. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:883–890, 2016 相似文献
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95.
Differences in oscillatory whistles produced by spinner (Stenella longirostris) and pantropical spotted (Stenella attenuata) dolphins 下载免费PDF全文
Pina Gruden Paul R. White Julie N. Oswald Yvonne Barkley Salvatore Cerchio Marc Lammers Simone Baumann‐Pickering 《Marine Mammal Science》2016,32(2):520-534
Acoustic recordings of two closely related species, spinner dolphin (Stenella longirostris) and pantropical spotted dolphin (Stenella attenuata), were investigated from four different geographic locations: two in the Central Tropical Pacific, one in the Eastern Tropical Pacific and one in the Indian Ocean. The two delphinid species occur in tropical and warm temperate waters, with overlapping ranges. They produce very similar vocalizations, but at the same time their calls exhibit a certain degree of intraspecific variation among different geographic locations as has been observed in other delphinid species. Oscillatory whistles (whistles with at least two oscillations in their frequency contours) were identified and manually extracted from the recordings. Whistles with four or more maxima (oscillations) occurred only in spinner dolphins and they were present in all geographic regions investigated. In addition, the oscillatory whistles with two and three maxima were significantly more frequent in spinner than in spotted dolphins. The differences in oscillatory whistles for these two species seem to be consistent across study areas and therefore, could be used in addition to other whistle features to help distinguish between them. 相似文献
96.
José Angel Herrera‐Vásquez Deibis Ortega Ana Belkis Romero Salvatore Davino Luis Carlos Mejía Stefano Panno Mario Davino 《Journal of Phytopathology》2016,164(2):102-113
The key regions in Panama involved in open field‐ and greenhouse‐grown commercial tomato production, including the Chiriquí, Veraguas, Herrera, Los Santos, Coclé and Panama Oeste provinces, were surveyed for the incidence and distribution of begomoviruses in the growing seasons of 2011 and 2012. The surveys took place in 14 of the 51 districts of the above‐mentioned provinces and comprised all relevant tomato production areas of the provinces. A total of 28 tomato plots were surveyed. The exact location of each plot was geo‐referenced using a hand‐held Global Positioning System unit. In total, 319 individual tomato plants (181 in 2011 and 138 in 2012) were sampled. Plants displayed diverse combinations of virus‐like symptoms of different severity, including necrosis, yellowing, mosaic, mottling, rolling, curling, distortion and puckering of leaves, reduced leaf size, and stunted growth. DNA was extracted from each plant for a subsequent polymerase chain reaction (PCR) analysis, using two sets of degenerate primers able to detect members of the genus Begomovirus. The samples displaying a positive reaction were subsequently analysed with specific primer pairs to identify the affecting begomoviruses. A total of 42.3% of all collected samples showed a positive signal to PCRs. Three begomovirus species were detected with the species‐specific set of primers; in particular, in the samples obtained in 2011, Potato yellow mosaic Panama virus (PYMPV), Tomato leaf curl Sinaloa virus (ToLCSiV) and Tomato yellow mottle virus (TYMoV) were detected, while in the 2012 samples, only PYMPV and ToLCSiV were found. To our knowledge, this is the first reported incidence of ToLCSiV and TYMoV in Panamanian tomato crops. 相似文献
97.
Natalizia Miceli Emilia Cav Salvatore Ragusa Francesco Cacciola Paola Dugo Luigi Mondello Andreana Marino Fabrizio Cincotta Concetta Condurso Maria Fernanda Taviano 《化学与生物多样性》2019,16(4)
This study aimed to characterize the phenolic and the volatile constituents and to establish the antioxidant potential and the toxicity of a hydroalcoholic extract obtained from the leaves and flower buds of Matthiola incana (L.) R.Br. subsp. incana growing wild in Sicily (Italy). By HPLC‐PDA/ESI‐MS analysis, 12 phenolics (two phenolic acid derivatives and ten flavonoids) were identified, and eight of them were reported for the first time; luteolin‐glucoside was the main component (57.07 mg/g±0.87 % RSD). By SPME‐GC/MS, 47 volatile constituents were fully characterized, and dimethyl trisulfide turned out to be the most abundant one (33.24 %). The extract showed moderate activity both in the DPPH and in the reducing power assays (IC50=2.32±0.24 mg/mL; ASE/mL=12.29±0.42); it did not inhibit the lipid peroxidation, whereas it was found to possess good chelating properties reaching approximately 90 % activity at the highest tested dose. Moreover, the extract protected growth and survival from H2O2‐induced oxidative stress in Escherichia coli. Finally, the extract was non‐toxic against Artemia salina (LC50>1000 μg/mL). These findings increase the knowledge of M. incana subsp. incana and they could be helpful to a chemosystematic distinguishing of this subspecies also demonstrating that the aerial parts represent a safe source of antioxidants. 相似文献
98.
Ramon Velazquez Eric Ferreira Sara Knowles Chaya Fux Alexis Rodin Wendy Winslow Salvatore Oddo 《Aging cell》2019,18(6)
Currently, there are no effective therapies to ameliorate the pathological progression of Alzheimer's disease (AD). Evidence suggests that environmental factors may contribute to AD. Notably, dietary nutrients are suggested to play a key role in mediating mechanisms associated with brain function. Choline is a B‐like vitamin nutrient found in common foods that is important in various cell functions. It serves as a methyl donor and as a precursor for production of cell membranes. Choline is also the precursor for acetylcholine, a neurotransmitter which activates the alpha7 nicotinic acetylcholine receptor (α7nAchR), and also acts as an agonist for the Sigma‐1 R (σ1R). These receptors regulate CNS immune response, and their dysregulation contributes to AD pathogenesis. Here, we tested whether dietary choline supplementation throughout life reduces AD‐like pathology and rescues memory deficits in the APP/PS1 mouse model of AD. We exposed female APP/PS1 and NonTg mice to either a control choline (1.1 g/kg choline chloride) or a choline‐supplemented diet (5.0 g/kg choline chloride) from 2.5 to 10 months of age. Mice were tested in the Morris water maze to assess spatial memory followed by neuropathological evaluation. Lifelong choline supplementation significantly reduced amyloid‐β plaque load and improved spatial memory in APP/PS1 mice. Mechanistically, these changes were linked to a decrease of the amyloidogenic processing of APP, reductions in disease‐associated microglial activation, and a downregulation of the α7nAch and σ1 receptors. Our results demonstrate that lifelong choline supplementation produces profound benefits and suggest that simply modifying diet throughout life may reduce AD pathology. 相似文献
99.
Elona Cekani José Luis López-Guerra Rodrigo Barrientos Patricia Tavera Juan Manuel Praena-Fernandez Eleonor Rivin del Campo Ignacio Azinovic Raul Matute 《Reports of Practical Oncology and Radiotherapy》2019,24(3):298-305
AimThe purpose of this study is to evaluate the long term tolerability of hypofractionated helical tomotherapy (HT) in localized prostate cancer patients.BackgroundPrevious hypofractionated schedules with conventional RT were associated with excessive toxicity, likely due to inadequate sophistication of treatment delivery. There are few data about late toxicity after HT.Materials and methodsWe evaluated 38 patients with primary adenocarcinoma of the prostate. There were 9 (24%), 15 (39%), and 14 (37%) patients with high, intermediate, and low risk, respectively. Patients were treated with hypofractionated HT from May 2008 to February 2011. Hypofractionation regimens included: 68.04 Gy at 2.52 Gy/fraction (N = 25; 66%), 70 Gy at 2.5 Gy/fraction (N = 4; 11%) and 70.2 Gy at 2.6 Gy/fraction (N = 9; 23%). Late genitourinary (GU) and gastrointestinal (GI) toxicity was scored using the Radiation Therapy Oncology Group scoring system.ResultsMedian age at diagnosis was 70 years (range 49–80) and median follow-up, 5.8 years. Late grade 1, 2 and 3 GI toxicity were 13%, 24%, and 2.6%, respectively. Late grade 1, 2, 3 GU toxicity were 29%, 21%, and 8%, respectively. Sexual toxicity was evaluated in 19 patients to be grade 1, 2 in 11% and grade 3 in 16%. Multivariate analysis showed that patients with higher values of rectum V50 associated with late GI toxicity (P = 0.025). Patients with PSA ≤8 (P = 0.048) or comorbidities (P = 0.013) at diagnosis were associated with higher late GU toxicity. Additionally, PSA ≤8 also associated with moderate (grade ≥2) late GU toxicity in the multivariate analysis (P = 0.028).ConclusionsHypofractionated HT can be delivered safely with limited rates of moderate and severe late toxicity. The proportion of the rectum that receives a moderate and high dose, having comorbidities, and PSA at diagnosis seem to associate with long term toxicity. 相似文献
100.
Amy M. Van Cise Robin W. Baird Charles Scott Baker Salvatore Cerchio Diane Claridge Russell Fielding Brittany Hancock‐Hanser Jacobo Marrero Karen K. Martien Antonio A. Mignucci‐Giannoni Erin M. Oleson Marc Oremus M. Michael Poole Patricia E. Rosel Barbara L. Taylor Phillip A. Morin 《Molecular ecology》2019,28(11):2886-2902
Genomic phylogeography plays an important role in describing evolutionary processes and their geographic, ecological, or cultural drivers. These drivers are often poorly understood in marine environments, which have fewer obvious barriers to mixing than terrestrial environments. Taxonomic uncertainty of some taxa (e.g., cetaceans), due to the difficulty in obtaining morphological data, can hamper our understanding of these processes. One such taxon, the short‐finned pilot whale, is recognized as a single global species but includes at least two distinct morphological forms described from stranding and drive hunting in Japan, the “Naisa” and “Shiho” forms. Using samples (n = 735) collected throughout their global range, we examine phylogeographic patterns of divergence by comparing mitogenomes and nuclear SNP loci. Our results suggest three types within the species: an Atlantic Ocean type, a western/central Pacific and Indian Ocean (Naisa) type, and an eastern Pacific Ocean and northern Japan (Shiho) type. mtDNA control region differentiation indicates these three types form two subspecies, separated by the East Pacific Barrier: Shiho short‐finned pilot whale, in the eastern Pacific Ocean and northern Japan, and Naisa short‐finned pilot whale, throughout the remainder of the species' distribution. Our data further indicate two diverging populations within the Naisa subspecies, in the Atlantic Ocean and western/central Pacific and Indian Oceans, separated by the Benguela Barrier off South Africa. This study reveals a process of divergence and speciation within a globally‐distributed, mobile marine predator, and indicates the importance of the East Pacific Barrier to this evolutionary process. 相似文献