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41.
Notomista E Pennacchio F Cafaro V Smaldone G Izzo V Troncone L Varcamonti M Di Donato A 《Microbial ecology》2011,61(3):582-594
Novosphingobium sp. PP1Y, isolated from a surface seawater sample collected from a closed bay in the harbour of Pozzuoli (Naples, Italy),
uses fuels as its sole carbon and energy source. Like some other Sphingomonads, this strain can grow as either planktonic
free cells or sessile-aggregated flocks. In addition, this strain was found to grow as biofilm on several types of solid and
liquid hydrophobic surfaces including polystyrene, polypropylene and diesel oil. Strain PP1Y is not able to grow on pure alkanes
or alkane mixtures but is able to grow on a surprisingly wide range of aromatic compounds including mono, bi, tri and tetracyclic
aromatic hydrocarbons and heterocyclic compounds. During growth on diesel oil, the organic layer is emulsified resulting in
the formation of small biofilm-coated drops, whereas during growth on aromatic hydrocarbons dissolved in paraffin the oil
layer is emulsified but the drops are coated only if the mixtures contain selected aromatic compounds, like pyrene, propylbenzene,
tetrahydronaphthalene and heterocyclic compounds. These peculiar characteristics suggest strain PP1Y has adapted to efficiently
grow at the water/fuel interface using the aromatic fraction of fuels as the sole carbon and energy source. 相似文献
42.
Gaytán F Tarradas E Bellido C Morales C Sánchez-Criado JE 《Biology of reproduction》2002,67(4):1140-1147
In the presence of indomethacin, an inhibitor of prostaglandin (PG) synthesis, the gonadotropin surge induces abnormal follicle rupture at the basolateral follicle sides, thus preventing effective ovulation in rats. This study was undertaken to analyze whether exogenous prostaglandin administration can overcome the antiovulatory action of indomethacin. Cycling rats were treated with vehicle (olive oil) or indomethacin (1 mg/rat) on the morning of proestrus. Rats treated with indomethacin were injected with different doses (50, 250, or 500 micro g/rat) of PGE(1), PGE(2), PGF(2alpha), or vehicle (saline) at 1900 h in proestrus. The ovulatory response was analyzed on the morning of estrus by evaluating follicle rupture and the location of the oocytes in serially sectioned ovaries. The number of oocytes in the oviducts was also counted in rats treated with the highest prostaglandin doses. In indomethacin-treated rats, most newly formed corpora lutea showed abnormal follicle rupture at the basolateral sides. In addition, invasion of the ovarian stroma and blood and lymphatic vessels by granulosa cells and follicular fluid was observed. Prostaglandins of the E series, and especially PGE(1), inhibited abnormal follicle rupture and restored ovulation, although the number of oocytes in the oviducts were significantly decreased. PGF(2alpha) was only partially effective in inhibiting abnormal follicle rupture and restoring ovulation. These data suggest that prostaglandins of the E series, and particularly PGE(1), play a crucial role in ovulation by determining the targeting of follicle rupture at the apex, thus allowing release of oocytes to the periovarian space. 相似文献
43.
44.
Carrasco-Marín E Rodriguez-Del Rio E Frande-Cabanes E Tobes R Pareja E Lecea-Cuello MJ Ruiz-Sáez M Madrazo-Toca F Hölscher C Alvarez-Dominguez C 《The Journal of biological chemistry》2012,287(18):14310-14324
Phagosomes are critical compartments for innate immunity. However, their role in the protection against murine listeriosis has not been examined. We describe here that listericidal phago-receptosomes are induced by the function of IFN-γ or IL-6 as centralized compartments for innate and adaptive immunity because they are able to confer protection against murine listeriosis. These phago-receptosomes elicited LLO(91-99)/CD8(+)- and LLO(189-201)/CD4(+)-specific immune responses and recruited mature dendritic cells to the vaccination sites controlled by T cells. Moreover, they present exceptional features as efficient vaccine vectors. First, they compartmentalize a novel listericidal STAT-1-mediated signaling pathway that confines multiple innate immune components to the same environment. Second, they show features of MHC class II antigen-loading competent compartments for cathepsin-D-mediated LLO processing. Third, murine cathepsin-D deficiencies fail to develop protective immunity after vaccination with listericidal phago-receptosomes induced by IFN-γ or IL-6. Therefore, it appears that the connection of STAT-1 and cathepsin-D in a single compartment is relevant for protection against listeriosis. 相似文献
45.
Sara Bruschini Simona di Martino Maria Elena Pisanu Luigi Fattore Claudia De Vitis Valentina Laquintana Simonetta Buglioni Eugenio Tabbì Andrea Cerri Paolo Visca Gabriele Alessandrini Francesco Facciolo Christian Napoli Marcella Trombetta Antonio Santoro Anna Crescenzi Gennaro Ciliberto Rita Mancini 《Journal of cellular physiology》2020,235(3):1877-1887
46.
Neidy P. Cetz-Navarro Eugenio J. Carpizo-Ituarte Julio Espinoza-Avalos Guillermina Chee-Barragán 《PloS one》2015,10(2)
Macroalgae and filamentous turf algae (FTA) are abundant on degraded coral reefs, and the reproductive responses of corals may indicate sub-lethal stress under these conditions. The percentage of gametogenic stages (PGS) and the maximum diameter of eggs (MDE; or egg size) of Orbicella annularis were used to evaluate the effect of long- (7–10 months) and short-term (2.5 months) FTA removal (treatments T1 and T2, respectively) at both the beginning (May) and the end (August) of gametogenesis. Ramets (individual lobes of a colony) surrounded by FTA (T3) or crustose coralline algae (CCA; T4) were used as controls. The removal of FTA enhanced the development of gametes (i.e., a larger and higher percentage of mature gametes (PMG)) of O. annularis for T1 vs. T3 ramets in May and T1 and T2 vs. T3 ramets in August. Similar values of PGS and MDE between gametes from T3 and T4 in both May and August were unexpected because a previous study had shown that the same ramets of T4 (with higher tissue thickness, chlorophyll a cm-2 and zooxanthellae density and lower mitotic index values) were less stressed than ramets of T3. Evaluating coral stress through reproduction can reveal more sensitive responses than other biological parameters; within reproductive metrics, PGS can be a better stress indicator than egg size. The presence of turf algae strongly impacted the development of gametes and egg size (e.g., PMG in ramets with FTA removal increased almost twofold in comparison with ramets surrounded by FTA in August), most likely exerting negative chronic effects in the long run due to the ubiquity and permanence of turf algae in the Caribbean. These algae can be considered a stressor that affects coral sexual reproduction. Although the effects of turf algae on O. annularis are apparently less severe than those of other stressors, the future of this species is uncertain because of the combined impacts of these effects, the decline of O. annularis populations and the almost complete lack of recruitment. 相似文献
47.
Age of spent Octopus vulgaris and stress mark analysis using beaks of wild individuals 总被引:1,自引:0,他引:1
Catalina Perales-Raya Alba Jurado-Ruzafa Aurora Bartolomé Verónica Duque María Nazaret Carrasco Eugenio Fraile-Nuez 《Hydrobiologia》2014,725(1):105-114
Age estimation of the cephalopod Octopus vulgaris by using beaks has improved in recent years, but maximum age and longevity in the wild have not been confirmed due to the low availability of senescent wild octopuses. In this study, a beak analysis of lateral wall surfaces (LWS) from 20 spent specimens confirmed the 1-year lifecycle of the species in Central East Atlantic waters. Stress marks (checks) were clearly located in the daily increment sequence of rostrum sagittal sections (RSS). The highest daily variations in sea surface temperature (ΔT) that occurred during the last months of their lifetimes coincided with the locations of the marks on the beak, enabling confirmation of O. vulgaris beaks as life recorders for the first time. It also supports the daily deposition of RSS beak increments in the wild. Individuals were grouped into two main zones, at 20ºN and 18ºN, respectively. Both groups showed different thermal check patterns, in accordance with the oceanographic differences. Two other checks (not coinciding with high values of ΔT) were observed in RSS at averages of 15 and 28 days before death, respectively, which were interpreted as responding to senescent-related events. 相似文献
48.
Francisco J. Prado-Prado Octavio Martinez de la Vega Eugenio Uriarte Florencio M. Ubeira Kuo-Chen Chou Humberto González-Díaz 《Bioorganic & medicinal chemistry》2009,17(2):569-575
One limitation of almost all antiviral Quantitative Structure–Activity Relationships (QSAR) models is that they predict the biological activity of drugs against only one species of virus. Consequently, the development of multi-tasking QSAR models (mt-QSAR) to predict drugs activity against different species of virus is of the major vitally important. These mt-QSARs offer also a good opportunity to construct drug–drug Complex Networks (CNs) that can be used to explore large and complex drug-viral species databases. It is known that in very large CNs we can use the Giant Component (GC) as a representative sub-set of nodes (drugs) and but the drug–drug similarity function selected may strongly determines the final network obtained. In the three previous works of the present series we reported mt-QSAR models to predict the antimicrobial activity against different fungi [Gonzalez-Diaz, H.; Prado-Prado, F. J.; Santana, L.; Uriarte, E. Bioorg. Med. Chem. 2006, 14, 5973], bacteria [Prado-Prado, F. J.; Gonzalez-Diaz, H.; Santana, L.; Uriarte E. Bioorg. Med. Chem. 2007, 15, 897] or parasite species [Prado-Prado, F.J.; González-Díaz, H.; Martinez de la Vega, O.; Ubeira, F.M.; Chou K.C. Bioorg. Med. Chem. 2008, 16, 5871]. However, including these works, we do not found any report of mt-QSAR models for antivirals drug, or a comparative study of the different GC extracted from drug–drug CNs based on different similarity functions. In this work, we used Linear Discriminant Analysis (LDA) to fit a mt-QSAR model that classify 600 drugs as active or non-active against the 41 different tested species of virus. The model correctly classifies 143 of 169 active compounds (specificity = 84.62%) and 119 of 139 non-active compounds (sensitivity = 85.61%) and presents overall training accuracy of 85.1% (262 of 308 cases). Validation of the model was carried out by means of external predicting series, classifying the model 466 of 514, 90.7% of compounds. In order to illustrate the performance of the model in practice, we develop a virtual screening recognizing the model as active 92.7%, 102 of 110 antivirus compounds. These compounds were never use in training or predicting series. Next, we obtained and compared the topology of the CNs and their respective GCs based on Euclidean, Manhattan, Chebychey, Pearson and other similarity measures. The GC of the Manhattan network showed the more interesting features for drug–drug similarity search. We also give the procedure for the construction of Back-Projection Maps for the contribution of each drug sub-structure to the antiviral activity against different species. 相似文献
49.
Llamil Ruiz Nuria Reyes Kethia Aroche Reynier Báez Raymersy Aldana Eugenio Hardy 《Biologicals》2006,34(1):15-19
In this paper we evaluated the influence of the protein concentration and a formulation vehicle on the stability of recombinant human Interferon alpha 2b (rhIFN-alpha2b) in solution. The effect of the protein content (from 1 to 100 MIU/ml) at 37 degrees C, showed that higher concentration of this cytokine protected against the loss of bioactivity (antiviral titration) better than the lower concentrations. In contrast, rhIFN-alpha2b at 50 and 100 MIU/ml decreased the SDS/PAGE- and RP-HPLC-determined purity faster than samples at 1 or 10 MIU/ml. According to these results, 10 MIU/ml rhIFN-alpha2b was the best choice to evaluate the influence of a formulation on the stability of this cytokine. Taking this into consideration, we studied the stability of a liquid and albumin-free formulation of this protein at the recommended storage temperature (5+/-3 degrees C) and under accelerated conditions (28+/-2 degrees C). Accelerated storage results showed an acceptable biochemical stability of the active ingredient throughout 2 months. Real-time storage data confirmed the good biochemical stability of this formulation for 30 months. 相似文献
50.
Sugarcane (Saccharum X officinarum): A Reference Study for the Regulation of Genetically Modified Cultivars in Brazil 总被引:1,自引:0,他引:1
Cheavegatti-Gianotto A de Abreu HM Arruda P Bespalhok Filho JC Burnquist WL Creste S di Ciero L Ferro JA de Oliveira Figueira AV de Sousa Filgueiras T Grossi-de-Sá MD Guzzo EC Hoffmann HP de Andrade Landell MG Macedo N Matsuoka S de Castro Reinach F Romano E da Silva WJ de Castro Silva Filho M César Ulian E 《Tropical plant biology》2011,4(1):62-89
Global interest in sugarcane has increased significantly in recent years due to its economic impact on sustainable energy production. Sugarcane breeding and better agronomic practices have contributed to a huge increase in sugarcane yield in the last 30?years. Additional increases in sugarcane yield are expected to result from the use of biotechnology tools in the near future. Genetically modified (GM) sugarcane that incorporates genes to increase resistance to biotic and abiotic stresses could play a major role in achieving this goal. However, to bring GM sugarcane to the market, it is necessary to follow a regulatory process that will evaluate the environmental and health impacts of this crop. The regulatory review process is usually accomplished through a comparison of the biology and composition of the GM cultivar and a non-GM counterpart. This review intends to provide information on non-GM sugarcane biology, genetics, breeding, agronomic management, processing, products and byproducts, as well as the current technologies used to develop GM sugarcane, with the aim of assisting regulators in the decision-making process regarding the commercial release of GM sugarcane cultivars. 相似文献