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101.
102.
Azzurra Stefanucci Andrea Angeli Marilisa Pia Dimmito Grazia Luisi Sonia Del Prete Clemente Capasso 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):945-950
Six tripeptides incorporating acidic amino acid residues were prepared for investigation as activators of β- and γ-carbonic anhydrases (CAs, EC 4.2.1.1) from the pathogenic bacteria Vibrio cholerae, Mycobacterium tuberculosis, and Burkholderia pseudomallei. The primary amino acid residues that are involved in the catalytic mechanisms of these CA classes are poorly understood, although glutamic acid residues near the active site appear to be involved. The tripeptides that contain Glu or Asp residues can effectively activate VchCAβ and VchCAγ (enzymes from V. cholerae), Rv3273 CA (mtCA3, a β-CA from M. tuberculosis) and BpsCAγ (γ-CA from B. pseudomallei) at 0.21–18.1?µM levels. The position of the acidic residues in the peptide sequences can significantly affect bioactivity. For three of the enzymes, tripeptides were identified that are more effective activators than both l-Glu and l-Asp. The tripeptides are also relatively selective because they do not activate prototypical α-CAs (human carbonic anhydrases I and II). Because the role of CA activators in the pathogenicity and life cycles of these infectious bacteria are poorly understood, this study provides new molecular probes to explore such processes. 相似文献
103.
104.
Martial Bernoux Maria Da Conceio Santana Carvalho Boris Volkoff Carlos Clemente Cerri 《Global Change Biology》2001,7(7):779-787
This paper presents a first approximation of net CO2 fluxes from mineral soil due to land use, land‐use changes and forestry (LULUCF) activities in Brazil for the periods 1970–90 and 1975–95. The methodology employed is an adaptation of the approach proposed by the IPCC in ‘Revised 1996 guidelines for national greenhouse gas inventories’, which is based on the variations in soil C stocks as a function of changes in land‐use activities. The calculation was done separately for each Brazilian state and subsequently summarized for all of Brazil. The annual fluxes for Brazil indicate a net emission of CO2 to the atmosphere, which decreased from 93.3 Tg CO2 for the period 1970–90 to 46.4 Tg CO2 for the period 1975–95. This corresponded to yearly net emission rates of 11.0 g CO2 m?2 year?1 for the 1970–90 period and 5.5 g CO2 m?2 year?1 for the 1975–95 period. Within each administrative region, considerable differences in the yearly emission rates between the states could be observed. Several sources of uncertainties could be identified. The most important uncertainties were linked to the impact factor values, which represent changes in native C stock associated with conversion of the native vegetation to agricultural use. 相似文献
105.
106.
New Treatment of Medullary and Papillary Human Thyroid Cancer: Biological Effects of Hyaluronic Acid Hydrogel Loaded With Quercetin Alone or in Combination to an Inhibitor of Aurora Kinase 下载免费PDF全文
107.
Javier Ribal M. Loreto Fenollosa Purificación García-Segovia Gabriela Clemente Neus Escobar Neus Sanjuán 《The International Journal of Life Cycle Assessment》2016,21(5):631-645
Purpose
This study aims to develop a model with which to build diets taking into account nutritional, climate change and economic aspects. A case study is used to test the proposed model, consisting of finding the optimal menus for school children in Spain from combinations of 20 starters, 20 main dishes and 7 desserts for a 20-day planning period.Methods
An optimizing technique, specifically integer goal programming, is used as a means of designing diets which take into account the aforementioned aspects. Goal programming (GP) is used to design those menus that meet, or nearly meet, all the requirements with respect to caloric content, caloric share among macronutrients, nutrients to encourage and nutrients to limit, while reducing the carbon footprint (CFP) and the lunch budget. In order to have real, acceptable dishes, a school catering company provided information about the typical dishes they serve. The CFP of each dish was assessed, based on literature about life cycle assessment and CFP studies on food products. The nutritional value of each dish was obtained from databases, whereas prices were gathered from a wholesaler.Results and discussion
After solving the goal programming model for several CFP and budget goals, the results show reductions with respect to the average CFP of between ?13 and ?24 %, and reductions with respect to the average budget between ?10 and ?15 % while maintaining the nutritional aspects similar to the average of the proposed menus. The results show that a wide range of budget is available, maintaining an almost constant CFP and meeting nutritional requirements to a similar degree; therefore, it is possible to avoid trade-offs between the CFP and the budget. The analysis of the dishes selected shows how the optimization model, in general, avoids the dishes which have a high CFP and high price and which are low in iron content, but high in protein and cholesterol.Conclusions
Goal programming constitutes a suitable tool for designing diets which are economically, environmentally and nutritionally sustainable. Its flexibility enables specific issues to be studied, such as the existence of possible trade-offs between budget and CFP, attained by changing the budget and the CFP goals. By means of an iterative process, new dishes could be introduced or the existing ones could be improved, thus providing catering companies with useful information.108.
Carlos Landa-Solís Julio Granados-Montiel Anell Olivos-Meza Carmina Ortega-Sánchez Mónica Cruz-Lemini Cecilia Hernández-Flores María Eugenia Chang-González Ricardo Gómez García Brenda Olivos-Díaz María Cristina Velasquillo-Martínez Carlos Pineda Clemente Ibarra 《Cell and tissue banking》2016,17(1):137-145
Mobilized peripheral blood (MPB) bone marrow cells possess the potential to differentiate into a variety of mesenchymal tissue types and offer a source of easy access for obtaining stem cells for the development of experimental models with applications in tissue engineering. In the present work, we aimed to isolate by magnetic activated cell sorting CD90+ cells from MPB by means of the administration of Granulocyte-Colony Stimulating Factor and to evaluate cell proliferation capacity, after thawing of the in vitro culture of this population of mesenchymal stem cells (MSCs) in sheep. We obtained a median of 8.2 ± 0.6 million of CD90+ cells from the 20-mL MPB sample. After thawing, at day 15 under in vitro culture, the mean CD90+ cells determined by flow cytometry was 92.92 ± 1.29 % and cell duplication time determined by crystal violet staining was 47.59 h. This study describes for the first time the isolation, characterization, and post-in vitro culture thawing of CD90+ MSCs from mobilized peripheral blood in sheep. This population can be considered as a source of MSCs for experimental models in tissue engineering research. 相似文献
109.
Daniela Vullo Sonia Del Prete Sameh M. Osman Zeid AlOthman Clemente Capasso William A. Donald Claudiu T. Supuran 《Bioorganic & medicinal chemistry letters》2017,27(1):77-80
Activation of the γ-class carbonic anhydrase (CAs, EC 4.2.1.1) from the pathogenic bacterium Burkholderia pseudomallei (BpsγCA) with a series of natural and non-natural amino acids and aromatic/heterocyclic amines has been investigated. The best BpsγCA activators were d-His, l-DOPA, d-Trp, 4-amino-l-Phe, dopamine, 2-(2-aminoethyl)pyridine, 2-aminoethyl-piparazine/morpholine and l-adrenaline, which showed activation constants ranging between 9 and 86 nM. The least effective activators were l-His, l-Phe and 2-pyridyl-methylamine, with KAs in the range of 1.73–24.7 μM. As little is known about the role of γ-CAs in the lifecycle and virulence of this saprophytic bacterium, this study may shed some light on such phenomena. This is the first CA activation study of a γ-CA from a pathogenic bacterium, the only other such study being on the enzyme discovered in the archaeon Methanosarcina thermophila, Cam. 相似文献
110.
Archipelagos of the Anthropocene: rapid and extensive differentiation of native terrestrial vertebrates in a single metropolis 下载免费PDF全文
Bethan L. Littleford‐Colquhoun Christofer Clemente Martin J. Whiting Daniel Ortiz‐Barrientos Celine H. Frère 《Molecular ecology》2017,26(9):2466-2481
Some of the best evidence for rapid evolutionary change comes from studies of archipelagos and oceanic islands. City parks are analogous systems as they create geographically isolated green spaces that differ in size, structure and complexity. Very little, however, is known about whether city parks within a single urban centre drive selection and result in the diversification of native species. Here, we provide evidence for the rapid genetic and morphological differentiation of a native lizard (Intellagama lesueurii) at four geographically close yet unconnected parks within one city. Year of establishment of each city park varied from 1855 (oldest) to 2001 (youngest) equating to a generation time range of 32 to three generations. Genetic divergence among city park populations was large despite the small pairwise geographic distances (<5 km) and found to be two to three times higher for microsatellites and three to 33 times higher for mtDNA relative to nonurban populations. Patterns of morphological differentiation were also found to be most extensive among the four city park populations. In contrast to nonurban populations, city park populations showed significant differentiation in relative body size, relative head and limb morphology and relative forelimb and hindlimb length. Crucially, we show that these patterns of differentiation are unlikely to have been caused by founder events and/or drift alone. Our results suggest that city park ‘archipelagos’ could represent theatres for rapid evolution that may, in time, favour adaptive diversification. 相似文献