Record of massive upwellings from the Pacific large low shear velocity province.

Large igneous provinces, as the surface expression of deep mantle processes, play a key role in the evolution of the planet. Here we analyse the geochemical record and timing of the Pacific Ocean Large Igneous Provinces and preserved accreted terranes to reconstruct the history of pulses of mantle plume upwellings and their relation with a deep-rooted source like the Pacific large low-shear velocity Province during the Mid-Jurassic to Upper Cretaceous. Petrological modelling and geochemical data suggest the need of interaction between these deep-rooted upwellings and mid-ocean ridges in pulses separated by ∼10-20 Ma, to generate the massive volumes of melt preserved today as oceanic plateaus. These pulses impacted the marine biota resulting in episodes of anoxia and mass extinctions shortly after their eruption.

Factors associated with mitochondrial dysfunction in circulating peripheral blood lymphocytes from HIV-infected people.

Nucleoside analogue reverse transcriptase inhibitor (NRTI)-associated mitochondrial toxicity is an important issue in the clinical management of HIV infection. The aim of this study was the detection of mitochondrial dysfunction by flow cytometry in lymphocytes from HIV-infected individuals and its association with blood lactate levels, clinical and virologic status, and the different NRTI-based therapies. Lower peripheral blood lymphocytes with mitochondrial dysfunction (PBLmd) percentages were observed in healthy controls (1.2, interquartile range [IQR] = 0.4-1.9) than in patients (2.2, IQR = 0.9-3.7; P < 0.01). Stavudine-containing therapy showed higher PBLmd percentages (3.0, IQR = 1.1-4.5) than no treatment (2.1, IQR = 0.8-2.8; P < 0.05) or zidovudine-based therapy (0.9, IQR = 0.3-1.4; P < 0.01). A significant inverse correlation was found between PBLmd and CD4 T-cell percentage and absolute count. Patients with an AIDS diagnosis had higher PBLmd percentage (2.7, IQR = 1.1-4.4) than HIV-positive non-AIDS patients (1.4, IQR = 0.6-3.0; P = 0.012). In multivariate analysis, use of stavudine (odds ratio [OR] = 5.86, 95% CI = 1.81-19.01, P = 0.003) and CD4 T-cell counts <200/microL (OR = 4.51, 95% CI = 1.38-14.70, P = 0.012) were independent predictors of high PBLmd percentage. This cross-sectional study shows that antiretroviral drugs can impair the in vivo mitochondrial function of PBLs.

Interacción in vivo del Cu(II) con cefotaxima / (Cu)II in vivo interaction with cefotaxime

Este trabajo estudia la reacción del cobre II con una cefalosporina,la cefotoxima, in vivo; los mecanismos catalíticos que implicanla presencia de complejos ternarios, su farmacocinética y su farmacodinamiaque afectan a la actividad del antibiótico. Las diferenciasmás significativas entre las ratas intoxicadas y control fueron observadasen riñón, pulmón e hígado. También hemos estudiado la actividadmicrobicida en Bacillus subtilis CECT 356, Escherichia coliCECT 434, Escherichia coli CECT 616, Staphilococus aureus sppaureus CECT 435, Staphilococus aureus spp aureus CECT 239(AU)

The presence of Cu(II) in penicillin and cephalosporin solutions,has been proved, to promote in vitro the antibiotic degradation tothe corresponding acid derivates. HPLC studies provided anadditional evidence for the reaction mechanism. The mechanisms ofCu(II) catalysis involve a ternary complex. This work was undertakento study the consequences of this degradation in vivo upper thepharmacokinetic, pharmacodynamic and activity of the antibioticcefotaxime. It is one of the most used «third-generation»cephalosporin in the world, this is because of that the interactioncefotaxime-metal deserved our attention. Our results remarked alower concentration of free cefotaxime in blood, liver, spleen, kidney,lung and heart in organs from animals suffering Cu-intoxication.The differences more significant between intoxicated and controlrats were observed in liver, lung and kidney. In addition cefotaximelinked to copper lose most of the microbicidal activity againstbacterial strains of Bacillus subtilis CECT 356, Escherichia coli CECT434, Escherichia coli CECT 616, Staphilococus aureus spp aureusCECT 435, Staphilococus aureus spp aureus CECT 239, in plate tests.It means that cefotaxime would become ineffective as antibiotic inmetal poisoned patients(AU)