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51.
González-Bergonzoni Ivan D’Anatro Alejandro Vidal Nicolás Stebniki Samanta Tesitore Giancarlo Silva Ivana Teixeira de Mello Franco 《Ecosystems》2019,22(8):1736-1753
Ecosystems - The origin of resources supporting metazoan biomass in rivers has long been a subject of debate. The river wave concept (RWC) postulates that the energetic basis of food webs varies... 相似文献
52.
Olusegun O. Osunkoya Jens G. Froese Sam Nicol Christine Perrett Kerri Moore Jason Callander Shane Campbell 《Austral ecology》2019,44(7):1123-1138
Invasive alien plant species threaten agriculture and biodiversity globally and require ongoing management to minimise impacts. However, the large number of invasive species means that a risk‐based approach to prioritisation is needed, taking into account the spatial scale of management decisions and myriad of available information. Here, we developed a risk‐based inventory of invasive plants in Queensland, Australia, using both current species distribution/abundance and the severity of their impacts. Our assessment followed a comprehensive data collection process including a scoping of local government pest management plans, herbarium records, the published literature and structured elicitation of expert knowledge during a series of regional stakeholder workshops. From ~300 plant species that were identified as established and/or emerging invaders in the State, only one‐third were considered by practitioners to pose significant risks across regions to be considered management priorities. We aggregated regional species lists into a statewide priority list and analysed the data set (107 species) for historical, geographical, floristic and ecological patterns. Regions on the mainland eastern seaboard of the State share similar invasive plant communities, suggesting that these regions may form a single management unit, unlike the western/inland and the extreme far north (Torres Strait Islands) regions, which share fewer invasive plant species. Positive correlations were detected between invasiveness and time since introduction for some but not all plant life forms. Stakeholders identified research and management priorities for the invasive plant list, including biological control options, public awareness/education, effective herbicide use, ecology/taxonomy and risk analysis. In the course of the exercise, a statewide invasive plant priority list of high‐, medium‐ and low‐impact scores for policy, research and management was compiled. Finally, our approach to invasive plant species prioritisation highlighted that planning and policy documents are not necessarily reflected at the grass‐root level in terms of species identity and management priorities. 相似文献
53.
54.
Manzano Carolina Melchert Nicolás A. Coll Araoz Maria V. Virla Eduardo G. Luft Albarracin Erica 《BioControl》2022,67(1):27-37
BioControl - Cosmocomoidea annulicornis (Ogloblin) (Hymenoptera: Mymaridae) is a solitary egg parasitoid of the sharpshooter Tapajosa rubromarginata (Signoret) (Hemiptera: Cicadellidae), vector of... 相似文献
55.
Nicolás Gastón Brukman Sol Yanel Nuñez Lis del Carmen Puga Molina Mariano Gabriel Buffone Alberto Darszon Patricia Sara Cuasnicu Vanina Gabriela Da Ros 《Journal of cellular physiology》2019,234(4):5276-5288
Capacitation is a mandatory process for the acquisition of mammalian sperm fertilization competence and involves the activation of a complex and still not fully understood system of signaling pathways. Under in vitro conditions, there is an increase in both protein tyrosine phosphorylation (pTyr) and intracellular Ca2+ levels in several species. In human sperm, results from our group revealed that pTyr signaling can be blocked by inhibiting proline-rich tyrosine kinase 2 (PYK2). Based on the role of PYK2 in other cell types, we investigated whether the PYK2-dependent pTyr cascade serves as a sensor for Ca 2+ signaling during human sperm capacitation. Flow cytometry studies showed that exposure of sperm to the PYK2 inhibitor N-[2-[[[2-[(2,3-dihydro-2-oxo-1 H-indol-5-yl)amino]-5-(trifluoromethyl)-4-pyrimidinyl]amino]methyl]phenyl]- N-methyl-methanesulfonamide hydrate (PF431396) produced a significant and concentration-dependent reduction in intracellular Ca 2+ levels during capacitation. Further studies revealed that PF431396-treated sperm exhibited a decrease in the activity of CatSper, a key sperm Ca 2+ channel. In addition, time course studies during capacitation in the presence of PF431396 showed a significant and sustained decrease in both intracellular Ca 2+ and pH levels after 2 hr of incubation, temporarily coincident with the activation of PYK2 during capacitation. Interestingly, decreases in Ca 2+ levels and progressive motility caused by PF431396 were reverted by inducing intracellular alkalinization with NH 4Cl, without affecting the pTyr blockage. Altogether, these observations support pTyr as an intracellular sensor for Ca 2+ entry in human sperm through regulation of cytoplasmic pH. These results contribute to a better understanding of the modulation of the polymodal CatSper and signaling pathways involved in human sperm capacitation. 相似文献
56.
Hevia Alejandra Iachini Ricardo Fernández Julián Lazzari Julieta Suárez-Alvarez Roberto Abrantes Rubén Toranzo Adriana Refojo Nicolás Canteros Cristina 《Mycopathologia》2019,184(5):701-706
Mycopathologia - Mycelial basidiomycetes rarely produce mycoses in animals including humans. We report a case of a 9-year-old female mongrel dog with lesions in the prescapular lymph nodes. The... 相似文献
57.
Cecilia Nigro Alessia Leone Michele Longo Immacolata Prevenzano Thomas H. Fleming Antonella Nicolò Luca Parrillo Rosa Spinelli Pietro Formisano Peter P. Nawroth Francesco Beguinot Claudia Miele 《生物化学与生物物理学报:疾病的分子基础》2019,1865(1):73-85
Impaired angiogenesis leads to long-term complications and is a major contributor of the high morbidity in patients with Diabetes Mellitus (DM). Methylglyoxal (MGO) is a glycolysis byproduct that accumulates in DM and is detoxified by the Glyoxalase 1 (Glo1). Several studies suggest that MGO contributes to vascular complications through mechanisms that remain to be elucidated. In this study we have clarified for the first time the molecular mechanism involved in the impairment of angiogenesis induced by MGO accumulation.Angiogenesis was evaluated in mouse aortic endothelial cells isolated from Glo1-knockdown mice (Glo1KD MAECs) and their wild-type littermates (WT MAECs). Reduction in Glo1 expression led to an accumulation of MGO and MGO-modified proteins and impaired angiogenesis of Glo1KD MAECs. Both mRNA and protein levels of the anti-angiogenic HoxA5 gene were increased in Glo1KD MAECs and its silencing improved both their migration and invasion. Nuclear NF-?B-p65 was increased 2.5-fold in the Glo1KD as compared to WT MAECs. Interestingly, NF-?B-p65 binding to HoxA5 promoter was also 2-fold higher in Glo1KD MAECs and positively regulated HoxA5 expression in MAECs. Consistent with these data, both the exposure to a chemical inhibitor of Glo1 “SpBrBzGSHCp2” (GI) and to exogenous MGO led to the impairment of migration and the increase of HoxA5 mRNA and NF-?B-p65 protein levels in microvascular mouse coronary endothelial cells (MCECs).This study demonstrates, for the first time, that MGO accumulation increases the antiangiogenic factor HoxA5 via NF-?B-p65, thereby impairing the angiogenic ability of endothelial cells. 相似文献
58.
Cebrián C Aresté C Nicolás A Olivé P Carceller A Piulats J Meseguer A 《The Journal of biological chemistry》2001,276(31):29410-29419
The gene for kidney androgen-regulated protein (KAP) is the most abundant and specific gene expressed in mouse kidney proximal tubule cells, where it is tightly regulated by steroid and thyroid hormones in different tubule segments. Despite the cell-specific expression, strict regulatory mechanisms, and relative abundance, nothing is known of the function of its encoded protein, which does not exhibit known structural or functional domains, or homologies with other sequences in the data bases. We raised monoclonal antibodies against KAP, which specifically recognize a protein with an apparent molecular mass of 20 kDa in crude kidney homogenates, the distribution and regulation of which parallel that of its mRNA. To gain insight into its function, we performed a yeast two hybrid screen and determined that KAP specifically interacts with cyclophilin B. Furthermore, cyclosporine A (CsA)-treated mice exhibited a significant decrease in KAP levels, and tetracycline-controlled overexpression of KAP in stably transfected proximal tubule cells significantly decreased the toxic effects of CsA. Taken together, these results indicate a functional relationship among KAP-, cyclophilin B-, and CsA-mediated nephrotoxicity and suggest an important role of KAP in renal physiology, providing new data on the molecular mechanisms implied in the toxic effects of CsA. 相似文献
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60.
Horita T Komi PV Nicol C Kyröläinen H 《European journal of applied physiology and occupational physiology》1999,79(2):160-167
The purpose of the present study was to investigate the effect of stretch-shortening-cycle-induced muscle damage on the time course of mechanical behaviour in the drop jump. Ten healthy male subjects performed submaximal stretch-shortening cycle (SSC) exercise on a special sledge apparatus. Exhaustion occurred on average within 3 min. A drop jump (DJ) test from a 50-cm height was performed before and immediately after the sledge exercise as well as 2 h, 2 days and 4 days later. The fatigue exercise showed relatively high blood lactate concentration [12.5 (SD 2.6) mmol x l(-1)] and an increase of serum creatine kinase (CK) activity delayed by 2 days [540 (SD 407) U x l(-1)]. The initial decline in the jump performance (before - immediately after) was related negatively to the early recovery in performance (immediately after 2 h) (P < 0.05). The early recovery of the knee joint moment at the end of stretch showed a negative correlation to the delayed decrease in DJ performance (2 h 2 days) (P < 0.01). Thus, the DJ performance showed an initial decline followed by an early recovery and a secondary decline. Both the initial decline and early recovery in the knee joint moment at the end of stretch were related to the corresponding initial (after 2 h) (P < 0.05) and secondary increases (2 h - 2 days) (P < 0.01) in CK. It is suggested that the early recovery as well as the initial decline in the knee joint function could depend on the degree of muscle damage. Delayed decrease in initial stiffness (2 h - 2 days) was negatively related to the corresponding changes in the knee joint angle at touch down in DJ (P < 0.001). These interactions would imply that the decrease in the stiffness regulation and the modulation of the prelanding motor control might be attributable to secondary muscle damage during 2 days after the SSC exercise. Therefore, it may be suggested that the changes in the DJ performance after the exhausting SSC exercise accompany the progress of muscle damage observed by the corresponding increase in serum CK concentration and the corresponding deterioration of stiffness regulation and motor control in DJ. 相似文献