Phosphorylated protein phosphatase 2A determines poor outcome in patients with metastatic colorectal cancer.

BACKGROUND: Protein phosphatase 2A (PP2A) is a tumour suppressor frequently inactivated in human cancer and its tyrosine-307 phosphorylation has been reported as a molecular inhibitory mechanism. METHODS: Expression of phosphorylated PP2A (p-PP2A) was evaluated in 250 metastatic colorectal cancer (CRC) patients. Chi-square, Kaplan-Meier and Cox analyses were used to determine correlations with clinical and molecular parameters and impact on clinical outcomes. RESULTS: High p-PP2A levels were found in 17.2% cases and were associated with ECOG performance status (P=0.001) and presence of synchronous metastasis at diagnosis (P=0.035). This subgroup showed substantially worse overall survival (OS) (median OS, 6.0 vs 26.2 months, P<0.001) and progression-free survival (PFS) (median PFS, 3.8 vs 13.3 months, P<0.001). The prognostic impact of p-PP2A was particularly evident in patients aged <70 years (P<0.001). Multivariate analysis revealed that p-PP2A retained its prognostic impact for OS (hazard ratio 2.7; 95% confidence interval, 1.8-4.1; P<0.001) and PFS (hazard ratio 3.0; 95% confidence interval, 1.8-5.0; P<0.001). CONCLUSIONS: Phosphorylated PP2A is an alteration that determines poor outcome in metastatic CRC and represents a novel potential therapeutic target in this disease, thus enabling to define a subgroup of patients who could benefit from future treatments based on PP2A activators.

Active angiogenesis in metastatic renal cell carcinoma predicts clinical benefit to sunitinib-based therapy.

BACKGROUND: Sunitinib represents a widely used therapy for metastatic renal cell carcinoma patients. Even so, there is a group of patients who show toxicity without clinical benefit. In this work, we have analysed pivotal molecular targets involved in angiogenesis (vascular endothelial growth factor (VEGF)-A, VEGF receptor 2 (KDR), phosphorylated (p)KDR and microvascular density (MVD)) to test their potential value as predictive biomarkers of clinical benefit in sunitinib-treated renal cell carcinoma patients. METHODS: Vascular endothelial growth factor-A, KDR and pKDR-Y1775 expression as well as CD31, for MVD visualisation, were determined by immunohistochemistry in 48 renal cell carcinoma patients, including 23 metastatic cases treated with sunitinib. Threshold was defined for each biomarker, and univariate and multivariate analyses for progression-free survival (PFS) and overall survival (OS) were carried out. RESULTS: The HistoScore mean value obtained for VEGF-A was 121.6 (range, 10-300); for KDR 258.5 (range, 150-300); for pKDR-Y1775 10.8 (range, 0-65) and the mean value of CD31-positive structures for MVD visualisation was 49 (range, 10-126). Statistical differences for PFS (P=0.01) and OS (P=0.007) were observed for pKDR-Y1775 in sunitinib-treated patients. Importantly, pKDR-Y1775 expression remained significant after multivariate Cox analysis for PFS (P=0.01; HR: 5.35, 95% CI, 1.49-19.13) and for OS (P=0.02; HR: 5.13, 95% CI, 1.25-21.05). CONCLUSIONS: Our results suggest that the expression of phosphorylated (i.e., activated) KDR in tumour stroma might be used as predictive biomarker for the clinical outcome in renal cell carcinoma first-line sunitinib-treated patients.

Baseline corticosterone and stress response in the Thorn-tailed Rayadito (Aphrastura spinicauda) along a latitudinal gradient.

Glucocorticoids are essential for life and their secretion is regulated by the hypothalamic-pituitary-adrenal axis (HPA). The HPA axis is often divided into two components: baseline glucocorticoids levels and stress response glucocorticoids levels, which are affected by changes in ambient temperature and productivity among others factors. An approximation to evaluate how a species copes with these changes is to evaluate differences of this hormone amongst populations of the same species that inhabit places ideally presenting all the possible combinations of temperature and productivity. We aimed to evaluate whether environmental temperature or productivity, represent challenges in terms of stress in the Thorn-tailed Rayadito (Aphrastura spinicauda). We examined circulating baseline levels of CORT and stress responses from three populations, covering the whole geographic distribution of the species across large gradients in weather conditions. If low temperature influences baseline CORT levels, we expect higher levels of this hormone in the southernmost population (higher latitude). However, if productivity is the factor that influences baseline CORT levels, we expect the contrary pattern, that is, lower values of this hormone in the southernmost population (more productive environment). We observed that baseline CORT levels presented lower values in the southernmost population, supporting the environmental productivity hypothesis. Secondly, we tested the hypothesis that individuals breeding at higher latitudes should have a lower stress response than individuals breeding at lower latitudes. Contrary to our expectations, we found that stress response did not vary among populations in any of the three years. We concluded that low environmental temperatures did not represent a stress situation for the Thorn-tailed Rayadito if food abundance was sufficient to support energetic demands.

Effects of Feed Solution pH on Polyelectrolyte Multilayer Nanofiltration Membranes.

Over the past decade polyelectrolyte multilayer (PEM)-based membranes have gained a lot of interest in the field of nanofiltration (NF) as an alternative to conventional polyamide-based thin film composite membranes. With great variety in fabrication conditions, these membranes can achieve superior properties such as high chemical resistance and excellent filtration performance. Some of the most common polyelectrolytes used to prepare NF membranes are weak, meaning that their charge density depends on pH within the normal window of operation relevant for potential applications (pH 0-14). This might cause a dependency of membrane properties on the pH of filtered solutions, as indicated by other applications of PEMs. In this work, the susceptibility of membrane structure (swelling and surface charge) and performance (permeability, molecular weight cutoff, and salt retention) toward the pH of the filtration solution was studied for four fundamentally different PEM systems: poly(diallyldimethylammonium chloride) (PDADMAC)/poly(sodium-4-styrenesulfonate) (PSS) (strong/strong), poly(allylamine hydrochloric acid) (PAH)/poly(acrylic acid) (PAA) (weak/weak), and PAH/PSS (weak/strong) and PAH/PSS+PAH/PAA (asymmetric). Slight variations in structure and performance of the PDADMAC/PSS-based membranes were observed. On the contrary, structure and performance of PAH/PAA-based membranes are very susceptible to feed solution pH. A continuous change in charge density with variation in pH significantly affects salt retention. An increased swelling at pH 9 translates to variation in permeability and molecular weight cutoff of the membrane. The susceptibility of PAH/PSS-based membranes to pH is less pronounced compared to the PAH/PAA-based membranes since only one of the polyelectrolytes involved is weak. No structural changes were observed, indicating additional specific interactions between the polyelectrolytes other than electrostatic forces that stabilize film structure. A combination of the PAH/PSS and PAH/PAA system (8 + 2 bilayers) also displays a clear dependency of both membrane structure and performance on solution pH, where PAH/PSS is dominating due to a higher bilayer number.

Differences in acute lung response to elastase instillation in two rodent species may determine differences in severity of emphysema development.

Elastase intratracheal instillation induces early emphysema in rodents. However, Syrian Golden hamsters develop more severe emphysema than Sprague-Dawley rats. We have reported species differences in oxidant/antioxidant balance modulating antiprotease function early after instillation. We now hypothesize that other components of the initial lung response to elastase might also be species-dependent. Sprague-Dawley rats and Syrian Golden hamsters received a single dose of pancreatic elastase (0.55 U/100 g body wt) to study acute lung injury biomarkers. Using serum, lung, and bronchoalveolar lavage fluid (BALF) samples, we evaluated changes in alveolar-capillary permeability, alpha 1-antitrypsin (α(1)-AT) concentration and activity, glutathione content, and proinflammatory cytokines. Rats showed a large increase in alveolar-capillary permeability and few hemorrhagic changes, whereas hamsters exhibited large hemorrhagic changes (P < 0.01) and mild transendothelial passage of proteins. Western blots showed a 30-fold increase in BALF α(1)-AT concentration in rats and only a 7-fold increase in hamsters (P < 0.001), with [α(1)-AT-elastase] complexes only in rats, suggesting differences in antiprotease function. This was confirmed by the α(1)-AT bioassay showing 20-fold increase in α(1)-AT activity in rats and only twofold increase in hamsters (P < 0.001). In rats, results were preceded by a 3-, 60-, and 20-fold increase in IL-6, IL-1ß, and TNF-α respectively (P < 0.001). In hamsters, only IL-1ß and TNF-α showed mild increases. All parameters studied were back to baseline by 4 days. In conclusion, several components of the initial lung response showed species differences. Cytokine release pattern and functional inhibition of α(1)-AT were the most significant components differing among species and could account for differences in susceptibility to elastase.

EVI1 controls proliferation in acute myeloid leukaemia through modulation of miR-1-2.

BACKGROUND: The EVI1(ecotropic virus integration site 1) gene codes for a zinc-finger transcription factor, whose transcriptional activation leads to a particularly aggressive form of acute myeloid leukaemia (AML). Although, EVI1 interactions with key proteins in hematopoiesis have been previously described, the precise role of this transcription factor in promoting leukaemic transformation is not completely understood. Recent works have identified specific microRNA (miRNA) signatures in different AML subgroups. However, there is no analysis of miRNAs profiles associated with EVI1 overexpression in humans. METHODS: We performed QT-RT-PCR to assess the expression of 250 miRNAs in cell lines with or without EVI1 overexpression and in patient samples. We used ChIP assays to evaluated the possible binding of EVI1 binding to the putative miRNA promoter. Proliferation of the different cell lines transfected with the anti- or pre-miRs was quantified by MTT. RESULTS: Our data showed that EVI1 expression was significantly correlated with the expression of miR-1-2 and miR-133-a-1 in established cell lines and in patient samples. ChIP assays confirmed that EVI1 binds directly to the promoter of these two miRNAs. However, only miR-1-2 was involved in abnormal proliferation in EVI1 expressing cell lines. CONCLUSIONS: Our data showed that EVI1 controls proliferation in AML through modulation of miR-1-2. This study contributes to further understand the transcriptional networks involving transcription factors and miRNAs in AML.

Magnetoencephalographic pattern of epileptiform activity in children with early-onset autism spectrum disorders.

OBJECTIVE: To provide further data around magnetoencephalographic (MEG) findings in early-onset autism spectrum disorders (ASD). METHODS: Thirty-six children (mean age 7 years) diagnosed of PDD (DSM-IV, ICD-10) were studied. There were 22 children with autistic disorder, 9 with Asperger's syndrome, and 5 with pervasive developmental disorder not otherwise specified (PDD-NOS). According to the Childhood Autism Rating Scale (CARS), the autistic disorder was mild to moderate in 11, and severe in 11. Neuroimaging studies using three-dimensional MRI as well as simultaneous MEG-EEG and fusion techniques through magnetic source imaging (MSI) were performed, with the aid of anesthesia in non-cooperative patients. RESULTS: Most patients had no EEG abnormalities. All ASD children showed common specific abnormalities in the shape of low amplitude monophasic and biphasic spikes (isolated or short bursts) as well as acute waves, predominantly distributed in the perisylvian areas. In Asperger's syndrome, epileptiform spikes were mostly found in the right hemisphere. No lateralized epileptiform activity was observed in non-Asperger's autistic patients. CONCLUSIONS: MEG epileptiform activity is frequently documented in children with early-onset ASD. SIGNIFICANCE: Subclinical epileptiform activity is present especially in the perisylvian regions for many patients with ASD.

Cost-effectiveness analysis in the treatment of heavy menstrual bleeding in Spain.

OBJECTIVE: To compare the effectiveness and costs associated with first-line medical treatments for chronic heavy menstrual bleeding (HMB) in Spain. STUDY DESIGN: A cost-effectiveness analysis was conducted comparing the levonorgestrel-releasing intrauterine system (LNG-IUS) with the estradiol valerate/dienogest multiphase oral contraceptive (E2V/DNG), combined oral contraceptives (COC) and progestins (PROG). Study patients were fertile women diagnosed with HMB who initially wished to remain fertile. A Markov model based on reported clinical data and the opinion of a panel of experts was used. The time horizon of the analysis was 5 years. The analysis was conducted from the perspective of the Spanish National Health System (NHS), discounting both costs (€ 2013) and future effects at an annual rate of 3%. One-way sensitivity analyses and probabilistic sensitivity analysis were performed to test the robustness of the results. RESULTS: In the analysis at 5 years, the LNG-IUS was associated with a gain of 0.67, 2.22, and 3.53 symptoms free months (SFM) compared with E2V/DNG, COC and PROG, respectively. LNG-IUS contributed more quality-adjusted life months (QALM) than the other treatment alternatives (+1.74 vs. E2V/DNG, +3.33 vs. COC +3.53 vs. PROG). First-line LNG-IUS treatment resulted in savings of € 583, € 988, and € 1891 vs. E2V/DNG, COC and PROG, respectively. These cost benefits, coupled with the greater clinical benefits in terms of SFM and QALM, show that LNG-IUS is the dominant option (less costly and more effective). CONCLUSION: LNG-IUS is the medical treatment of choice and cost-saving option for the control of HMB in Spain.

Hearing results in the second stage of open mastoidectomy: A comparison of the different techniques.

OBJECTIVE: The goal of this study was to compare the hearing results obtained through different hearing-restoration techniques in open-cavity mastoidectomy. METHODS AND MATERIAL: A total of 116 ears operated on during the second stage of open mastoidectomy were studied. The hearing gain was registered as the difference between preoperative and 1-year postoperative conversational frequency means (500, 1000, 2000 Hz). High-pitched frequencies (4000 Hz) were used equally. Two groups of studies were carried out: in one study the stapes was intact, and in the other the stapes arch was absent. The columella techniques we examined, from a hearing point of view, are total and partial ossicular replacement prostheses, ossiculoplasty, cartilage with or without perichondrium, and the myringostapediopexy. RESULTS AND CONCLUSIONS: In the group of patients in whom the stapes was intact, the differences in high-pitched frequencies found between the different techniques were negligible, but the differences were quite significant in conversational frequencies, where the partial ossicular replacement prosthesis turned out to be the technique with the worst results. In ears in which only the footplate was present, the total ossicular replacement prosthesis gave better results than any other technique, both in conversational frequencies and in 4000-Hz frequency.

Progestin-only contraception and venous thromboembolism.

Combined oral contraceptives (COC) are the most popular contraceptive method in developed countries. Since their introduction there have been numerous changes and modifications in its composition with the aim to improve safety and tolerability while maintaining contraceptive efficacy. Most of the changes have been conducted on the progestin component, since most of the combinations include ethinyl estradiol as oestrogen. One of the adverse effects of COC is the increased risk of venous thromboembolism (VTE) in two clinical forms of presentation: deep vein thrombosis or pulmonary embolism. This review details the changes in haemostasis induced by progestin-only contraceptives and the risk of VTE in women who utilize this type of contraception; the relationship with other risk factors such as thrombophilia; the interactions of these contraceptives with anticoagulant treatment and finally the eligibility criteria for the use of hormonal contraception in women with previous VTE or thrombophilia carriers.

Seasonality and edge effect determine herbivory risk according to different plant association models.

We report evidence of hierarchical resource selection by large herbivores and plant neighbouring effects in a Mediterranean ecosystem. Plant palatability was assessed according to herbivore foraging decisions. We hypothesize that under natural conditions large herbivores follow a hierarchical foraging pattern, starting at the landscape scale, and then selecting patches and individual plants. A between- and within-patch selection study was carried out in an area formed by scrubland and pasture patches, connected by habitat edges. With regard to between-patch selection, quality-dependent resource selection is reported: herbivores mainly consume pasture in spring and woody plants in winter. Within-patch selection was also observed in scrub habitats, influenced by season, relative patch palatability and edge effect. We defined a Proximity Index (PI) between palatable and unpalatable plants, which allowed verification of neighbouring effects. In spring, when the preferred food resource (i.e. herbs) is abundant, we observed that in habitat edges large herbivores basically select the relatively scarce palatable shrubs, whereas inside scrubland, unpalatable shrub consumption was related to increasing PI. In winter, a very different picture was observed; there was low consumption of palatable species surrounded by unpalatable species in habitat edges, where the latter were more abundant. These outcomes could be explained though different plant associations described in the literature. We conclude that optimal foraging theory provides a conceptual framework behind the observed interactions between plants and large herbivores in Mediterranean ecosystems.

Economic evaluation of the levonorgestrel-releasing intrauterine system for the treatment of dysfunctional uterine bleeding in Spain.

OBJECTIVE: To compare the cost and effectiveness of the levonorgestrel-releasing intrauterine system (LNG-IUS) versus combined oral contraception (COC) and progestogens (PROG) in first-line treatment of dysfunctional uterine bleeding (DUB) in Spain. STUDY DESIGN: A cost-effectiveness and cost-utility analysis of LNG-IUS, COC and PROG was carried out using a Markov model based on clinical data from the literature and expert opinion. The population studied were women with a previous diagnosis of idiopathic heavy menstrual bleeding. The analysis was performed from the National Health System perspective, discounting both costs and future effects at 3%. In addition, a sensitivity analysis (univariate and probabilistic) was conducted. RESULTS: The results show that the greater efficacy of LNG-IUS translates into a gain of 1.92 and 3.89 symptom-free months (SFM) after six months of treatment versus COC and PROG, respectively (which represents an increase of 33% and 60% of symptom-free time). Regarding costs, LNG-IUS produces savings of € 174.2-309.95 and € 230.54-577.61 versus COC and PROG, respectively, after 6 months-5 years. Apart from cost savings and gains in SFM, quality-adjusted life months (QALM) are also favourable to LNG-IUS in all scenarios, with a range of gains between 1 and 2 QALM compared to COC and PROG. CONCLUSIONS: The results indicate that first-line use of the LNG-IUS is the dominant therapeutic option (less costly and more effective) in comparison with first-line use of COC or PROG for the treatment of DUB in Spain. LNG-IUS as first line is also the option that provides greatest health-related quality of life to patients.

PP2A impaired activity is a common event in acute myeloid leukemia and its activation by forskolin has a potent anti-leukemic effect.

Protein phosphatase 2A (PP2A) is a human tumor suppressor that inhibits cellular transformation by regulating the activity of several signaling proteins critical for malignant cell behavior. PP2A has been described as a potential therapeutic target in chronic myeloid leukemia, Philadelphia chromosome-positive acute lymphoblastic leukemia and B-cell chronic lymphocytic leukemia. Here, we show that PP2A inactivation is a recurrent event in acute myeloid leukemia (AML), and that restoration of PP2A phosphatase activity by treatment with forskolin in AML cells blocks proliferation, induces caspase-dependent apoptosis and affects AKT and ERK1/2 activity. Moreover, treatment with forskolin had an additive effect with Idarubicin and Ara-c, drugs used in standard induction therapy in AML patients. Analysis at protein level of the PP2A activation status in a series of patients with AML at diagnosis showed PP2A hyperphosphorylation in 78% of cases (29/37). In addition, we found that either deregulated expression of the endogenous PP2A inhibitors SET or CIP2A, overexpression of SETBP1, or downregulation of some PP2A subunits, might be contributing to PP2A inhibition in AML. In conclusion, our results show that PP2A inhibition is a common event in AML cells and that PP2A activators, such as forskolin or FTY720, could represent potential novel therapeutic targets in AML.