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851.
Gennaro Lettieri Velia Mollo Alessia Ambrosino Filomena Caccavale Jacopo Troisi Ferdinando Febbraio Marina Piscopo 《Molecular reproduction and development》2019,86(10):1357-1368
This study aims to assess the effects induced by 24 hr exposure to a subtoxic copper concentration on the reproductive system (gonads, spermatozoa, and protamine‐like [PL] proteins) of Mytilus galloprovincialis. Inductively coupled plasma–mass spectrometry indicated accumulation of this metal in gonads, spermatozoa, and PL proteins of exposed mussels. Further, real‐time polymerase chain reaction analyses showed altered expression levels of mt10 and PL proteins genes in spermatozoa and gonads, respectively, of exposed mussels. Protamine‐like proteins, which represent the main basic component of sperm chromatin of this organism, showed a higher DNA binding affinity and a different DNA binding mode in exposed mussels. Moreover, an increased amount of NaCl was required for the release from sperm nuclei of PL‐III, the main PL protein component. Finally, PL proteins extracted from exposed mussels promoted DNA oxidative damage in the presence of H 2O 2. These results demonstrate that the tolerable copper amount could also affect the properties of PL proteins and determine the negative effects on the reproductive system of this organism. These analyses could be useful to develop quick and efficient chromatin‐based genotoxicity tests for pollution biomonitoring programs. 相似文献
852.
In primitively eusocial insects, air temperature is the environmental factor that primarily affects colony cycle. Several studies demonstrated interspecific differences in the adaptation of eusocial insects to local air temperature. Nevertheless, studies on intraspecific adaptations are rare. In this study, we investigate the influence of air temperature on local adaptations in behavior and colony productivity of Polistes biglumis foundresses living in warm and cold temperate zones. We hypothesized that foundresses from warm temperate zones would show a higher activity level compared to those from cold temperate zones before brood emergence, based on differences in air temperature between the two zones. After brood emergence, we expected a reduced foundress activity level in the warm climate zone, due to workers’ help. In contrast, foundresses living in the cold-climate zone, which do not produce workers, were expected to remain active throughout the nesting season. We also hypothesized that colony productivity was higher in warm-climate colonies. As expected, warm-climate foundresses reduced their activity level after brood emergence and, with their relatively large number of workers, continued egg production throughout the nesting season. Further studies are necessary to assess if these intraspecific differences are attributable to phenotypic plasticity or genetic divergence. 相似文献
853.
Eleonora Salvolini Eddi Buldreghini Guendalina Lucarini Arianna Vignini Alessia Giulietti Andrea Lenzi Laura Mazzanti Roberto Di Primio Giancarlo Balercia 《Histochemistry and cell biology》2014,142(5):569-575
Impaired male fertility may have a variety of causes, among which asthenozoospermia. In its etiology, several bioactive substances, such as cytokines may be involved. In this context, our aim was to evaluate the expression of interleukin-1β, cyclooxygenase-2, and hypoxia-inducible factor-1α, in spermatozoa isolated from normospermic fertile donors and asthenozoospermic infertile patients. We evaluated twenty-eight infertile patients affected by idiopathic asthenozoospermia and twenty-three normospermic fertile donors, age-matched. Sperm parameters were evaluated; immunohistochemical analysis and enzyme-linked immunosorbent assay were then performed in isolated spermatozoa. Spermatozoa from the asthenozoospermic group presented an increased expression of IL-1β, COX-2, and HIF-1α compared with the normospermic fertile subjects. Our results can lead us to speculate that the increased expression of these substances may influence sperm motility. Nevertheless, further studies are needed in order to assess whether these bioactive mediators have a potential relevance as targets in future therapeutic strategies for the treatment of male infertility. 相似文献
854.
Graziano Fiorito Andrea Affuso David B. Anderson Jennifer Basil Laure Bonnaud Giovanni Botta Alison Cole Livia D’Angelo Paolo De Girolamo Ngaire Dennison Ludovic Dickel Anna Di Cosmo Carlo Di Cristo Camino Gestal Rute Fonseca Frank Grasso Tore Kristiansen Michael Kuba Fulvio Maffucci Arianna Manciocco Felix Christopher Mark Daniela Melillo Daniel Osorio Anna Palumbo Kerry Perkins Giovanna Ponte Marcello Raspa Nadav Shashar Jane Smith David Smith António Sykes Roger Villanueva Nathan Tublitz Letizia Zullo Paul Andrews 《Invertebrate neuroscience : IN》2014,14(1):13-36
Cephalopods have been utilised in neuroscience research for more than 100 years particularly because of their phenotypic plasticity, complex and centralised nervous system, tractability for studies of learning and cellular mechanisms of memory (e.g. long-term potentiation) and anatomical features facilitating physiological studies (e.g. squid giant axon and synapse). On 1 January 2013, research using any of the about 700 extant species of “live cephalopods” became regulated within the European Union by Directive 2010/63/EU on the “Protection of Animals used for Scientific Purposes”, giving cephalopods the same EU legal protection as previously afforded only to vertebrates. The Directive has a number of implications, particularly for neuroscience research. These include: (1) projects will need justification, authorisation from local competent authorities, and be subject to review including a harm-benefit assessment and adherence to the 3Rs principles (Replacement, Refinement and Reduction). (2) To support project evaluation and compliance with the new EU law, guidelines specific to cephalopods will need to be developed, covering capture, transport, handling, housing, care, maintenance, health monitoring, humane anaesthesia, analgesia and euthanasia. (3) Objective criteria need to be developed to identify signs of pain, suffering, distress and lasting harm particularly in the context of their induction by an experimental procedure. Despite diversity of views existing on some of these topics, this paper reviews the above topics and describes the approaches being taken by the cephalopod research community (represented by the authorship) to produce “guidelines” and the potential contribution of neuroscience research to cephalopod welfare. 相似文献
855.
Alessia Calzolari Ernestina Saulle Maria Laura De Angelis Luca Pasquini Alessandra Boe Federica Pelacchi Lucia Ricci-Vitiani Marta Baiocchi Ugo Testa 《PloS one》2014,9(4)
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been reported to exhibit therapeutic activity in cancer. However, many tumors remain resistant to treatment with TRAIL. Therefore, small molecules that potentiate the cytotoxic effects of TRAIL could be used for combinatorial therapy. Here we found that the ionophore antibiotic salinomycin acts in synergism with TRAIL, enhancing TRAIL-induced apoptosis in glioma cells. Treatment with low doses of salinomycin in combination with TRAIL augmented the activation of caspase-3 and increased TRAIL-R2 cell surface expression. TRAIL-R2 upmodulation was required for mediating the stimulatory effect of salinomycin on TRAIL-mediated apoptosis, since it was abrogated by siRNA-mediated TRAIL-R2 knockdown. Salinomycin in synergism with TRAIL exerts a marked anti-tumor effect in nude mice xenografted with human glioblastoma cells. Our results suggest that the combination of TRAIL and salinomycin may be a useful tool to overcome TRAIL resistance in glioma cells and may represent a potential drug for treatment of these tumors. Importantly, salinomycin+TRAIL were able to induce cell death of well-defined glioblastoma stem-like lines. 相似文献
856.
857.
Heterochromatin domains are essential for normal chromosome functions. The Eri1 ribonuclease is a negative regulator of the RNA interference machinery; recent studies have shown that, in fission yeast lacking Eri1, heterochromatin formation is more promiscuous. 相似文献
858.
859.
Astegiano S Sidoti F Costa C Ostorero A Alotto D Castagnoli C Bergallo M Stella M Cavallo R 《The new microbiologica》2010,33(3):253-256
This study evaluated the detection of Human Cytomegalovirus (HCMV)-DNA in donors' skin samples. HCMV-DNA was quantified in 100 skin specimens, including 50 fresh samples and as many corresponding glycerol-preserved specimens by a home-made Real Time PCR. HCMV-DNA was detected in 19/50 (38%) fresh specimens and 23/50 (46%) glycerol-preserved (p = n.s.). Nevertheless, the mere detection of HCMV-DNA does not imply the presence of infectious virions and therefore does not imply a risk of HCMV transmission, as treatment with glycerol is particularly efficacious in inactivating viral particles. Therefore, HCMV serology confirms its pivotal role in the setting of skin grafting. 相似文献
860.