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1.
A Faroni S W Rothwell A A Grolla G Terenghi V Magnaghi A Verkhratsky 《Cell death & disease》2013,4(7):e743
Schwann cells (SCs) are fundamental for development, myelination and regeneration in the peripheral nervous system. Slow growth rate and difficulties in harvesting limit SC applications in regenerative medicine. Several molecules, including receptors for neurosteroids and neurotransmitters, have been suggested to be implicated in regulating physiology and regenerative potential of SCs. Adipose-derived stem cells (ASCs) can be differentiated into SC-like phenotype (dASC) sharing morphological and functional properties with SC, thus representing a valid SC alternative. We have previously shown that dASC express γ-aminobutyric-acid receptors, which modulate their proliferation and neurotrophic potential, although little is known about the role of other neurotransmitters in ASC. In this study, we investigated the expression of purinergic receptors in dASC. Using reverse transriptase (RT)-PCR, western blot analyses and immunocytochemistry, we have demonstrated that ASCs express P2X3, P2X4 and P2X7 purinoceptors. Differentiation of ASCs towards glial phenotype was accompanied by upregulation of P2X4 and P2X7 receptors. Using Ca2+-imaging techniques, we have shown that stimulation of purinoceptors with adenosine 5′-triphosphate (ATP) triggers intracellular Ca2+ signals, indicating functional activity of these receptors. Whole-cell voltage clamp recordings showed that ATP and BzATP induced ion currents that can be fully inhibited with specific P2X7 antagonists. Finally, using cytotoxicity assays we have shown that the increase of intracellular Ca2+ leads to dASC death, an effect that can be prevented using a specific P2X7 antagonist. Altogether, these results show, for the first time, the presence of functional P2X7 receptors in dASC and their link with critical physiological processes such as cell death and survival. The presence of these novel pharmacological targets in dASC might open new opportunities for the management of cell survival and neurotrophic potential in tissue engineering approaches using dASC for nerve repair. 相似文献
2.
Carlos Romero F. Oliveira Leda Rita D'A. Faroni Raul Narciso C. Guedes Angelo Pallini 《BioControl》2003,48(5):503-513
Recent reports of the biocontrolpotential of the mite species Acarophenaxlacunatus (Cross & Krantz) (Prostigmata:Acarophenacidae) and the lack of biologicalstudies on this regulatory agent led to thepresent study carried out under laboratoryconditions. The objective of the investigationwas to assess the host range of A. lacunatus,so far only reported as egg parasite ofRhyzopertha dominica (F.) (Coleoptera:Bostrichidae). Four Coleoptera species ofstored cereals were used: R. dominica,Tribolium castaneum (Herbst) (Tenebrionidae),Cryptolestes ferrugineus (Stephens)(Laemophloeidae) and Oryzaephilus surinamensis (L.) (Cucujidae). The highest rates of eggparasitism were observed on R. dominica and T.castaneum, leading to a significant decrease ofpopulations of both species and reduced wheatweight loss. A. lacunatus was also able toparasitize eggs of C. ferrugineus, but not ofO. surinamensis. These results indicate abroader host range of A. lacunatus thaninitially suspected and also strengthen itspossibility of use in integrated pestmanagement programs in storage environments. 相似文献
3.
The parasitic mite Acarophenax lacunatus kills the eggs upon which it feeds and seems to have potential as a biological control agent of stored grain pests. The lack of biological studies on this mite species led to the present study carried out in laboratory conditions at eight different temperatures (ranging from 20 to 41°C) and 60% relative humidity using Rhyzopertha dominica as host. The higher the temperature, the faster: (1) the attachment of female mites to the host egg (varying from 1 to 5 h); (2) the increase in body size of physogastric females (about twice faster at 40°C than at 20°C); and (3) the generation time (ranging from 40 to 220 h). In addition, the higher the temperature, the shorter the maximum female longevity (ranging from about 75 to 300 h). The two estimated temperature thresholds for development of A. lacunatus on R. dominica were 18 and 40°C. The average number of female and male offspring per gravid mite were 12.8 and 1.0, respectively, with sex ratios (females/total) ranging from 0.91 to 0.94 (maximum at 30°C). The net reproductive rate and intrinsic rate of increase also presented maximum values at 30°C (12.1 and 0.04, respectively). 相似文献
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5.
Larisse Faroni‐Perez Conrad Helm Ingo Burghardt Pat Hutchings María Capa 《Invertebrate Biology》2016,135(4):423-447
Sensory organs in Annelida are very diverse and may be useful for assessments of morphological adaptation and character evolution. We used several methods to provide new insights into processes underlying the evolutionary radiation of anterior sensory organs in Sabellariidae. The presence and morphological diversity of the median organ (MO) found in the group was reviewed in order to test its phylogenetic significance and possible relationships to the distribution and ecological traits of the lineages. To test the intraspecific phenotypic plasticity of the MO, molecular analyses were conducted that focused on mitochondrial and nuclear genes from populations of Idanthyrsus australiensis exhibiting variation in the morphology of the MO. We used an integrative microscopical study of the ontogeny of Sabellaria alveolata to describe the anterior sensory structures present in the larvae and the morphological changes occurring before, during, and after settlement. In larval stages, the palps and the dorsal hump (DH) exhibit distinct innervation. The larval DH organ, which is likely to play a major role in chemoreception for settlement, is interpreted as being the incipient form of the adult MO. These results suggest that annelid sensory organs including the MO may be useful for phylogenetic and developmental investigations. 相似文献
6.
Claudia G Petersen Fabiana C Massaro Ana L Mauri Joao BA Oliveira Ricardo LR Baruffi Jose G FrancoJr 《Reproductive biology and endocrinology : RB&E》2010,8(1):149
Background
The present study aimed to evaluate the efficacy of the hyaluronic acid (HA) binding assay in the selection of motile spermatozoa with normal morphology at high magnification (8400x). 相似文献7.
Michael J Stobart Debra Parchaliuk Sharon LR Simon Jillian LeMaistre Jozef Lazar Richard Rubenstein J David Knox 《Molecular neurodegeneration》2007,2(1):1-13
Background
Alzheimer's disease (AD) is characterized by a decline in cognitive function and accumulation of amyloid-β peptide (Aβ) in extracellular plaques. Mutations in amyloid precursor protein (APP) and presenilins alter APP metabolism resulting in accumulation of Aβ42, a peptide essential for the formation of amyloid deposits and proposed to initiate the cascade leading to AD. However, the role of Aβ40, the more prevalent Aβ peptide secreted by cells and a major component of cerebral Aβ deposits, is less clear. In this study, virally-mediated gene transfer was used to selectively increase hippocampal levels of human Aβ42 and Aβ40 in adult Wistar rats, allowing examination of the contribution of each to the cognitive deficits and pathology seen in AD.Results
Adeno-associated viral (AAV) vectors encoding BRI-Aβ cDNAs were generated resulting in high-level hippocampal expression and secretion of the specific encoded Aβ peptide. As a comparison the effect of AAV-mediated overexpression of APPsw was also examined. Animals were tested for development of learning and memory deficits (open field, Morris water maze, passive avoidance, novel object recognition) three months after infusion of AAV. A range of impairments was found, with the most pronounced deficits observed in animals co-injected with both AAV-BRI-Aβ40 and AAV-BRI-Aβ42. Brain tissue was analyzed by ELISA and immunohistochemistry to quantify levels of detergent soluble and insoluble Aβ peptides. BRI-Aβ42 and the combination of BRI-Aβ40+42 overexpression resulted in elevated levels of detergent-insoluble Aβ. No significant increase in detergent-insoluble Aβ was seen in the rats expressing APPsw or BRI-Aβ40. No pathological features were noted in any rats, except the AAV-BRI-Aβ42 rats which showed focal, amorphous, Thioflavin-negative Aβ42 deposits.Conclusion
The results show that AAV-mediated gene transfer is a valuable tool to model aspects of AD pathology in vivo, and demonstrate that whilst expression of Aβ42 alone is sufficient to initiate Aβ deposition, both Aβ40 and Aβ42 may contribute to cognitive deficits. 相似文献8.
De Oliveira CR Faroni LR Guedes RN Gonçalves JR Garcia FM 《Neotropical Entomology》2007,36(3):459-464
The aim of the present study was to assess the effect of six different temperatures on the development of Acarophenax lacunatus (Cross & Krantz) using eggs of Tribolium castaneum (Herbst) and Cryptolestes ferrugineus (Stephens) as hosts. The temperature affected the development of A. lacunatus. The largest values for the progeny (19 mites in T. castaneum and 15 mites in C. ferrugineus) were obtained at about 30 degrees C, as also observed for the net reproductive rate (Ro), which revealed that the A. lacunatus population increased 18 times in T. castaneum and 14 times in C. ferrugineus in a generation. The intrinsic rate of increase (r m) gradually increased with temperature, reaching the maximum value at 35 degrees C in T. castaneum (1,608) and C. ferrugineus (1,289). The generation time was negatively correlated with temperature, ranging from 1,60 to 4,85 days in T. castaneum and from 1,96 to 5,34 days in C. ferrugineus. These results suggest that the mite A. lacunatus may be used in programs of biological control of T. castaneum and C. ferrugineus in the tropics. 相似文献
9.
Gonçalves JR Faroni LR Guedes RN De Oliveira CR Garcia FM 《Neotropical Entomology》2007,36(2):247-253
The objective of this study was to evaluate the effect of different temperatures with the association of the mite Acarophenax lacunatus (Cross & Krantz) on the population suppression of Rhyzopertha dominica (Fabricius). The experimental units were petri dishes containing 40 g of whole wheat grains (13% moisture content) infested with 10 adults of R. dominica, under the temperatures of 20, 25, 30 and 35 masculineC, with or without A. lacunatus, in five replicates. Relative humidity of 60 +/- 5% and escotophase of 24h were used for all temperatures. Five days after the infestation, five mites were inoculated in each experimental unit. The evaluations were carried out at 20, 40, 60, 80, 100 and 120 days after R. dominica infestation. The interaction of the temperature with the parasite A. lacunatus was an important tool for the population suppression of R. dominica. In temperatures higher than 25 masculineC, however, despite the reduction of the immature stages of R. dominica, there was a high grain weight loss after 120 days. The maintenance of the temperature of the wheat grains stored at 20 masculineC can be used to complement the biological control of R. dominica with A. lacunatus. 相似文献
10.
Stephen LR Ellison Claire A English Malcolm J Burns Jacquie T Keer 《BMC biotechnology》2006,6(1):33-11