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91.
Steffen Schneider Thomas Hofmann Stefan Stinchcombe Maria Cecilia Rey Moreno Ivana Fegert Volker Strauss Sibylle Gröters Eric Fabian Jutta Thiaener Karma C. Fussell Bennard van Ravenzwaay 《Birth defects research. Part B, Developmental and reproductive toxicology》2013,98(3):230-246
Epoxiconazole, a triazole‐based fungicide, was tested in toxicokinetic, prenatal and pre‐postnatal toxicity studies in guinea pigs, following oral (gavage) administration at several dose levels (high dose: 90 mg/kg body weight per day). Maternal toxicity was evidenced by slightly increased abortion rates and by histopathological changes in adrenal glands, suggesting maternal stress. No compound‐related increase in the incidence of malformations or variations was observed in the prenatal study. In the pre‐postnatal study, epoxiconazole did not adversely affect gestation length, parturition, or postnatal growth and development. Administration of epoxiconazole did not alter circulating estradiol levels. Histopathological examination of the placentas did not reveal compound‐related effects. The results in guinea pigs are strikingly different to those observed in pregnant rats, in which maternal estrogen depletion, pathological alteration of placentas, increased gestation length, late fetal death, and dystocia were observed after administration of epoxiconazole. In the studies reported here, analysis of maternal plasma concentrations and metabolism after administration of radiolabeled epoxiconazole demonstrated that the different results in rats and guinea pigs were not due to different exposures of the animals. A comprehensive comparison of hormonal regulation of pregnancy and birth in murid rodents and primates indicates that the effects on pregnancy and parturition observed in rats are not applicable to humans. In contrast, the pregnant guinea pig shares many similarities to pregnant humans regarding hormonal regulation and is therefore considered to be a suitable species for extrapolation of related effects to humans. Birth Defects Res (Part B) 98:230–246, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
92.
Raquel Montero Manuela Grazina Ester López-Gallardo Julio Montoya Paz Briones Aleix Navarro-Sastre John M. Land Iain P. Hargreaves Rafael Artuch Maria del Mar O'Callaghan Cristina Jou Cecilia Jimenez Nuria Buján Mercè Pineda Angels García-Cazorla Andrés Nascimento Plácido Navas 《Mitochondrion》2013,13(4):337-341
We evaluated coenzyme Q10 (CoQ) levels in patients studied under suspicion of mitochondrial DNA depletion syndromes (MDS) (n = 39). CoQ levels were quantified by HPLC, and the percentage of mtDNA depletion by quantitative real-time PCR. A high percentage of MDS patients presented with CoQ deficiency as compared to other mitochondrial patients (Mann–Whitney-U test: p = 0.001). Our findings suggest that MDS are frequently associated with CoQ deficiency, as a possible secondary consequence of disease pathophysiology. Assessment of muscle CoQ status seems advisable in MDS patients since the possibility of CoQ supplementation may then be considered as a candidate therapy. 相似文献
93.
Cecilia Alsmark Åke Strese Christina Wedén Anders Backlund 《Phytochemistry Reviews》2013,12(3):531-542
Marine multi-cellular organisms are described as sources of many newly discovered bioactive compounds. Meanwhile, it has been demonstrated repeatedly for several natural products of reputed multicellular origin that they are, in fact, produced by endophytic unicellular organisms—such as microbial fungi or bacteria. Consequently, while studying compounds isolated from a living organism, it is essential to ensure that the sample integrity is not compromised. To test the diversity of the endobiome from Alcyonium digitatum, a cold water coral found along the Atlantic coasts of the northern hemisphere, we performed a culture dependent surveyed using a phylogenetic approach. A 1 cm3 cube from the interior tissue of A. digitatum was excised under aseptic conditions, homogenized, spread onto agar-based growth medium plates and incubated in 22 °C to promote microbial growth. Colonies were transferred to secondary medium plates, incubated, and after harvesting lysed using sterile water to release DNA. 16S and 23S rDNA regions were amplified using PCR, and sequenced for systematic evaluation using phylogenetic analysis. From this survey we identified a broad selection of bacteria, predominantly of the α-proteobacterial, bacteriodete, actinobacterial and firmicute lineages, demonstrating a significant biodiversity of the coral bacterial endobiome. 相似文献
94.
Cecilia U. D. Stenfors Linda Magnusson Hanson Gabriel Oxenstierna T?res Theorell Lars-G?ran Nilsson 《PloS one》2013,8(4)
Background
Cognitive complaints involving problems with concentration, memory, decision-making and thinking are relatively common in the work force. The sensitivity of both subjective and objective cognitive functioning to common psychiatric conditions, stress levels and to cognitive load makes it plausible that psychosocial working conditions play a role in cognitive complaints. Thus, this study aimed to test the associations between psychosocial work factors and cognitive complaints in nationally representative samples of the Swedish work force. Cross-sectional (n = 9751) and prospective (n = 3644; two time points two years apart) sequential multiple regression analyses were run, adjusting for general confounders, depressive- and sleeping problems. Additional prospective analyses were run adjusting for baseline cognitive complaints.Cross-sectional results
High quantitative demands, information and communication technology (ICT) demands, underqualification and conflicts were positively associated with cognitive complaints, while social support, good resources at work and overqualification were negatively associated with cognitive complaints in all models. Skill discretion and decision authority were weakly associated with cognitive complaints. Conflicts were more strongly associated with cognitive complaints in women than in men, after adjustment for general confounders.Prospective results
Quantitative job demands, ICT demands and underqualification were positively associated with future cognitive complaints in all models, including when adjusted for baseline cognitive complaints. Decision authority was weakly positively associated with future cognitive complaints, only after adjustment for depressive- and sleeping problems respectively. Social support was negatively associated with future cognitive complaints after adjustment for general confounders and baseline cognitive complaints. Skill discretion and resources were negatively associated with future cognitive complaints after adjustment for general confounders. The associations between quantitative demands and future cognitive complaints were stronger in women.Discussion/Conclusions
The findings indicate that psychosocial working conditions should be taken into account when considering cognitive complaints among employees. 相似文献95.
Nuno Bernardes Ana Sofia Ribeiro Sofia Abreu Bruna Mota Rute G. Matos Cecilia M. Arraiano Raquel Seruca Joana Paredes Arsenio M. Fialho 《PloS one》2013,8(7)
P-cadherin overexpression occurs in about 30% of all breast carcinomas, being a poor prognostic factor for breast cancer patients. In a cellular background of wild-type E-cadherin, we have previously shown that its expression promotes invasion, motility and migration of breast cancer cells due to the induced secretion of metalloproteases (MMPs) to the extracellular medium and to the concomitant shedding of a pro-invasive soluble form of this protein (sP-cad). Azurin is secreted by Pseudomonas aeruginosa and induces in vitro and in vivo cytotoxicity after its preferential penetration in human cancer cells relative to normal cells. Three different breast cancer cell lines, MCF-7/AZ.Mock, MCF-7/AZ.Pcad and SUM149 were treated with sub-killing doses of azurin. Invasion of these cells was measured using Matrigel Invasion Assays and MTT assays were performed to determine cell viability upon treatment and the effects on cadherins expression was determined by Western blot and Immunofluorescence. Gelatin Zymography was used to determine activity of MMP2 in the conditioned media of azurin treated and untreated cells and the phosphorylation levels of intracellular signaling proteins were determined by Western blot. The invasive phenotype of these breast cancer cells was significantly reduced by azurin. Azurin (50–100 µM) also caused a specific decrease on P-cadherin protein levels from 30–50% in MCF-7/AZ.Pcad and SUM149 breast cancer cell lines, but the levels of E-cadherin remain unaltered. More, the levels of sP-cad and the activity of MMP2 were reduced in the extracellular media of azurin treated cells and we also observed a decrease in the phosphorylation levels of both FAK and Src proteins. Our data show that azurin specifically targets P-cadherin, not E-cadherin, abrogating P-cadherin-mediated invasive effects and signaling. Therefore, azurin could possibly be considered a therapeutic tool to treat poor-prognosis breast carcinomas overexpressing P-cadherin in a wild type E-cadherin context. 相似文献
96.
Chiara Zoppellaro Anna Bin Paola Brun Serena Banzato Veronica Macchi Ignazio Castagliuolo Maria Cecilia Giron 《PloS one》2013,8(8)
Adenosine plays an important role in regulating intestinal motility and inflammatory processes. Previous studies in rodent models have demonstrated that adenosine metabolism and signalling are altered during chronic intestinal inflammatory diseases. However, the involvement of the adenosinergic system in the pathophysiology of gut dysmotility associated to a primary neurodysfunction is still unclear. Recently, we showed that the neurotropic Herpes simplex virus type-1 (HSV-1), orally inoculated to rodents, infects the rat enteric nervous system (ENS) and affects gut motor function without signs of systemic infection. In this study we examined whether changes in purinergic metabolism and signaling occur during permanent HSV-1 infection of rat ENS. Using isolated organ bath assays, we found that contraction mediated by adenosine engagement of A1 or A2A receptors was impaired at 1 and 6 weeks post-viral administration. Immunofluorescence studies revealed that viral infection of ENS led to a marked redistribution of adenosine receptors: A1 and A2B receptors were confined to the muscle layers whereas A2A and A3 receptors were expressed mainly in the myenteric plexus. Viral-induced ENS neurodysfunction influenced adenosine metabolism by increasing adenosine deaminase and CD73 levels in longitudinal muscle-myenteric plexus with no sign of frank inflammation. This study provides the first evidence for involvement of the adenosinergic system during HSV-1 infection of the ENS. As such, this may represent a valid therapeutic target for modulating gut contractility associated to a primary neurodysfunction. 相似文献
97.
The use of dried and re-hydrated biomass of the seagrass Posidonia oceanica was investigated as an alternative and –low-cost biomaterial for removal of vanadium(III) and molybdenum(V) from wastewaters. Initial characterisation of this biomaterial identified carboxylic groups on the cuticle as potentially responsible for cation sorption, and confirmed the toxic-metal bioaccumulation. The combined effects on biosorption performance of equilibrium pH and metal concentrations were investigated in an ideal single-metal system and in more real-life multicomponent systems. There were either with one metal (vanadium or molybdenum) and sodium nitrate, as representative of high ionic strength systems, or with the two metals (vanadium and molybdenum). For the single-metal solutions, the optimum was at pH 3, where a significant proportion of vanadium was removed (ca. 70%) while there was ca. 40% adsorption of molybdenum. The data obtained from the more real-life multicomponent systems showed that biosorption of one metal was improved both by the presence of the other metal and by high ionic strength, suggesting a synergistic effect on biosorption rather than competition. There data ware used for the development of a simple multi-metal equilibrium model based on the non-competitive Langmuir approach, which was successfully fitted to experimental data and represents a useful support tool for the prediction of biosorption performance in such real-life systems. Overall, the results suggest that biomass of P. oceanica can be used as an efficient biosorbent for removal of vanadium(III) and molybdenum(V) from aqueous solutions. This process thus offers an eco-compatible solution for the reuse of the waste material of leaves that accumulate on the beach due to both human activities and to storms at sea. 相似文献
98.
Jing Zhang Mingjian Zhou Zhenglin Ge Jie Shen Can Zhou Cecilia Gotor Luis C. Romero Xingliang Duan Xin Liu Deliang Wu Xianchao Yin Yanjie Xie 《Plant, cell & environment》2020,43(3):624-636
Recent studies have demonstrated that hydrogen sulfide (H2S) produced through the activity of l -cysteine desulfhydrase (DES1) is an important gaseous signaling molecule in plants that could participate in abscisic acid (ABA)-induced stomatal closure. However, the coupling of the DES1/H2S signaling pathways to guard cell movement has not been thoroughly elucidated. The results presented here provide genetic evidence for a physiologically relevant signaling pathway that governs guard cell in situ DES1/H2S function in stomatal closure. We discovered that ABA-activated DES1 produces H2S in guard cells. The impaired guard cell ABA phenotype of the des1 mutant can be fully complemented when DES1/H2S function has been specifically rescued in guard cells and epidermal cells, but not mesophyll cells. This research further characterized DES1/H2S function in the regulation of LONG HYPOCOTYL1 (HY1, a member of the heme oxygenase family) signaling. ABA-induced DES1 expression and H2S production are hyper-activated in the hy1 mutant, both of which can be fully abolished by the addition of H2S scavenger. Impaired guard cell ABA phenotype of des1/hy1 can be restored by H2S donors. Taken together, this research indicated that guard cell in situ DES1 function is involved in ABA-induced stomatal closure, which also acts as a pivotal hub in regulating HY1 signaling. 相似文献
99.
Berardo Cecilia Geritz Stefan Gyllenberg Mats Raoul Gaël 《Journal of mathematical biology》2020,80(7):2431-2468
Journal of Mathematical Biology - In this paper we introduce a formal method for the derivation of a predator’s functional response from a system of fast state transitions of the prey or... 相似文献