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51.
Carlo Dani Lucia Giannini Giovanna Bertini Simone Pratesi Iuri Corsini Mariangela Longini 《Free radical research》2013,47(12):1358-1363
The higher risk of respiratory problem in infants delivered by elective caesarean section in comparison with vaginally born infants may be favoured by lower level of nitric oxide (NO) and carbon monoxide (CO) and higher oxidative stress in infants born by caesarean section. We studied healthy term infants born by vaginal delivery or by elective caesarean section. Nitric oxide, CO, guanosine 3–5 cyclic monophosphate, total hydroperoxide and advanced oxidation protein products (AOPP) were measured at birth and 48–72 h of life. Nitric oxide, CO and cGMP were lower at birth and at 48–72 h of life in infants born by elective caesarean delivery. Total hydroperoxide and AOPP levels were similar in the two groups and increased from birth to 48–72 h of life. In conclusion, nitric oxide and CO concentrations were higher in term infants vaginally born than in infants born by elective caesarean section and decreased from birth to 48–72 h of life. The mode of delivery did not affect the oxidative stress which increases from birth to 48–72 h of life. 相似文献
52.
Lucia Fernandez-Arrojo Barbara Rodriguez-Colinas Patricia Gutierrez-Alonso Maria Fernandez-Lobato Miguel Alcalde Antonio O. Ballesteros Francisco J. Plou 《Process Biochemistry》2013,48(4):677-682
A modification of the classical calcium alginate enzyme entrapment technique is described aiming to overcome some of the limitations of the former gel-based biocatalysts. Dried alginate entrapped enzymes (DALGEEs) were obtained dehydrating calcium alginate gel beads containing entrapped enzymes. A fructosyltransferase from Aspergillus aculeatus, present in Pectinex Ultra SP-L, was entrapped using this technique. The resulting DALGEEs were successfully tested both operating batchwise and in a continuous fixed-bed reactor for fructooligosaccharides (FOS) synthesis from sucrose. Interestingly, DALGEEs did not re-swell upon incubation in concentrated (600 g/L) sucrose solutions, probably due to the lowered water activity (aw) of such media. Confocal laser scanning microscopy of DALGEEs revealed that the enzyme molecules accumulated preferably in the shell of the particles. DALGEEs showed an approximately 30-fold higher volumetric activity (300 U/mL) compared with the calcium alginate gel beads. Moreover, a significant enhancement (40-fold) of the space-time-yield of fixed-bed bioreactors was observed when using DALGEEs as biocatalyst compared with gel beads (4030 g/day L of FOS vs. 103 g/day L). The operational stability of fixed-bed reactors packed with DALGEEs was extraordinary, providing a nearly constant FOS composition of the outlet during at least 700 h. It was also noticeable their resistance against microbial attack, even after long periods of storage at room temperature. The DALGEEs immobilisation strategy may also be useful for other biotransformations, in particular when they take place in low aw media. 相似文献
53.
Cisgenesis is a genetic modification of a recipient organism with genetic material from a crossable organism. Trying to free cisgenics from the regulatory guidelines of genetically modified organisms (GMOs), some scientists have suggested to classify the genetically modified products by the origin of transferred genes. Aiming at exploring how scientists frame cisgenics in relation to current legal frameworks, we have sent an extensive survey to the totality of researchers working on cisgenics. Trying to provide cisgenics with a new, uncontroversial identity, the respondents present cisgenics as a method of obtaining “natural,” environmentally friendly and economically sustainable crops. However, such strategy is challenged by GMO corporations opposing a segmentation of the sector, and by the opponents of GMOs, who fear that deregulation on cisgenics leads to the deregulation of GMOs. Drawing from the concepts of bio-objectification and bio-identification, we show how the status of this bio-object is likely to remain contested and contestable. 相似文献
54.
Elena Bausch Hella Kohlhof Svetlana Hamm Rolf Krauss Roland Baumgartner Lucia Sironi 《PloS one》2013,8(11)
Microtubule inhibitors are invaluable tools in cancer chemotherapy: taxanes and vinca alkaloids have been successfully used in the clinic over the past thirty years against a broad range of tumors. However, two factors have limited the effectiveness of microtubule inhibitors: toxicity and resistance. In particular, the latter is highly unpredictable, variable from patient to patient and is believed to be the cause of treatment failure in most cases of metastatic cancers. For these reasons, there is an increasing demand for new microtubule inhibitors that can overcome resistance mechanisms and that, at the same time, have reduced side effects. Here we present a novel microtubule inhibitor, 4SC-207, which shows strong anti-proliferative activity in a large panel of tumor cell lines with an average GI50 of 11nM. In particular, 4SC-207 is active in multi-drug resistant cell lines, such as HCT-15 and ACHN, suggesting that it is a poor substrate for drug efflux pumps. 4SC-207 inhibits microtubule growth in vitro and in vivo and promotes, in a dose dependent manner, a mitotic delay/arrest, followed by apoptosis or aberrant divisions due to chromosome alignment defects and formation of multi-polar spindles. Furthermore, preliminary data from preclinical studies suggest low propensity towards bone marrow toxicities at concentrations that inhibit tumor growth in paclitaxel-resistant xenograft models. In summary, our results suggest that 4SC-207 may be a potential anti-cancer agent. 相似文献
55.
56.
Gea Guerriero Lucia Silvestrini Michael Obersriebnig Marco Salerno Dietmar Pum Joseph Strauss 《PloS one》2013,8(11)
The fungal cell wall constitutes an important target for the development of antifungal drugs, because of its central role in morphogenesis, development and determination of fungal-specific molecular features. Fungal walls are characterized by a network of interconnected glycoproteins and polysaccharides, namely α-, β-glucans and chitin. Cell walls promptly and dynamically respond to environmental stimuli by a signaling mechanism, which triggers, among other responses, modulations in wall biosynthetic genes’ expression. Despite the absence of cellulose in the wall of the model filamentous fungus Aspergillus nidulans, we found in this study that fungal growth, spore germination and morphology are affected by the addition of the cellulose synthase inhibitor dichlobenil. Expression analysis of selected genes putatively involved in cell wall biosynthesis, carried out at different time points of drug exposure (i.e. 0, 1, 3, 6 and 24 h), revealed increased expression for the putative mixed linkage β-1,3;1,4 glucan synthase celA together with the β-1,3-glucan synthase fksA and the Rho-related GTPase rhoA. We also compared these data with the response to Congo Red, a known plant/fungal drug affecting both chitin and cellulose biosynthesis. The two drugs exerted different effects at the cell wall level, as shown by gene expression analysis and the ultrastructural features observed through atomic force microscopy and scanning electron microscopy. Although the concentration of dichlobenil required to affect growth of A. nidulans is approximately 10-fold higher than that required to inhibit plant cellulose biosynthesis, our work for the first time demonstrates that a cellulose biosynthesis inhibitor affects fungal growth, changes fungal morphology and expression of genes connected to fungal cell wall biosynthesis. 相似文献
57.
Maria Glória Teixeira Jo?o Bosco Siqueira Jr Germano L. C. Ferreira Lucia Bricks Graham Joint 《PLoS neglected tropical diseases》2013,7(12)
A literature survey and analysis was conducted to describe the epidemiology of dengue disease in Brazil reported between 2000 and 2010. The protocol was registered on PROSPERO (CRD42011001826: http://www.crd.york.ac.uk/prospero/display_record.asp?ID=CRD42011001826). Between 31 July and 4 August 2011, the published literature was searched for epidemiological studies of dengue disease, using specific search strategies for each electronic database. A total of 714 relevant citations were identified, 51 of which fulfilled the inclusion criteria. The epidemiology of dengue disease in Brazil, in this period, was characterized by increases in the geographical spread and incidence of reported cases. The overall increase in dengue disease was accompanied by a rise in the proportion of severe cases. The epidemiological pattern of dengue disease in Brazil is complex and the changes observed during this review period are likely to have been influenced by multiple factors. Several gaps in epidemiological knowledge regarding dengue disease in Brazil were identified that provide avenues for future research, in particular, studies of regional differences, genotype evolution, and age-stratified seroprevalence.
Systematic Review Registration
PROSPERO registration number: CRD42011001826. 相似文献58.
59.
Thomas Jans Erika Graf Christian Jacob Ulrike Zwanzger Silke Groß-Lesch Swantje Matthies Evgeniy Perlov Klaus Hennighausen Melanie Jung Michael Rösler Monika Schulte-Altedorneburg Alexander von Gontard Susann Hänig Esther Sobanski Barbara Alm Luise Poustka Lucia Bliznak Michael Colla Laura Gentschow Roland Burghardt Harriet Salbach-Andrae Katja Becker Martin Holtmann Christine Freitag Andreas Warnke Alexandra Philipsen 《Attention deficit and hyperactivity disorders》2013,5(1):29-40
60.
Savino di Lernia Mary Anne Tafuri Marina Gallinaro Francesca Alhaique Marie Balasse Lucia Cavorsi Paul D. Fullagar Anna Maria Mercuri Andrea Monaco Alessandro Perego Andrea Zerboni 《PloS one》2013,8(2)
Cattle pastoralism is an important trait of African cultures. Ethnographic studies describe the central role played by domestic cattle within many societies, highlighting its social and ideological value well beyond its mere function as ‘walking larder’. Historical depth of this African legacy has been repeatedly assessed in an archaeological perspective, mostly emphasizing a continental vision. Nevertheless, in-depth site-specific studies, with a few exceptions, are lacking. Despite the long tradition of a multi-disciplinary approach to the analysis of pastoral systems in Africa, rarely do early and middle Holocene archaeological contexts feature in the same area the combination of settlement, ceremonial and rock art features so as to be multi-dimensionally explored: the Messak plateau in the Libyan central Sahara represents an outstanding exception. Known for its rich Pleistocene occupation and abundant Holocene rock art, the region, through our research, has also shown to preserve the material evidence of a complex ritual dated to the Middle Pastoral (6080–5120 BP or 5200–3800 BC). This was centred on the frequent deposition in stone monuments of disarticulated animal remains, mostly cattle. Animal burials are known also from other African contexts, but regional extent of the phenomenon, state of preservation of monuments, and associated rock art make the Messak case unique. GIS analysis, excavation data, radiocarbon dating, zooarchaeological and isotopic (Sr, C, O) analyses of animal remains, and botanical information are used to explore this highly formalized ritual and the lifeways of a pastoral community in the Holocene Sahara. 相似文献