971 resultados para aggressive displays
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Peripheral T-cell lymphomas (PTCLs) are heterogeneous and uncommon malignancies characterized by a usually aggressive clinical course. The current World Health Organization (WHO) classification delineates many entities grouped according to the clinical presentation as predominantly leukemic, cutaneous, extranodal, or nodal diseases. Yet, few genetic lesions serve as entity-defining markers. Using high-throughput methods, new recurrent genetic and molecular alterations are being discovered that are expected to refine the current classification and serve as diagnostic genetic markers and targets for novel therapies. There is increasing evidence that certain cellular subsets, in particular follicular helper T cells and gamma delta T cells, represent important defining markers and/or determinants of the biology of certain entities; nevertheless, the cellular derivation of many PTCL entities remains poorly characterized and there is evidence of plasticity in terms of cellular derivation (alpha-beta, gamma-delta, natural killer [NK]) especially in several extranodal entities with a cytotoxic profile. While most clonal NK/T-cell proliferations are in general highly malignant, some more indolent forms of NK or T-cell lympho-proliferations are being identified.
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Climate warming leads to a decrease in biodiversity. Organisms can deal with the new prevailing environmental conditions by one of two main routes, namely evolving new genetic adaptations or through phenotypic plasticity to modify behaviour and physiology. Melanin-based colouration has important functions in animals including a role in camouflage and thermoregulation, protection against UV-radiation and pathogens and, furthermore, genes involved in melanogenesis can pleiotropically regulate behaviour and physiology. In this article, I review the current evidence that differently coloured individuals are differentially sensitive to climate change. Predicting which of dark or pale colour variants (or morphs) will be more penalized by climate change will depend on the adaptive function of melanism in each species as well as how the degree of colouration covaries with behaviour and physiology. For instance, because climate change leads to a rise in temperature and UV-radiation and dark colouration plays a role in UV-protection, dark individuals may be less affected from global warming, if this phenomenon implies more solar radiation particularly in habitats of pale individuals. In contrast, as desertification increases, pale colouration may expand in those regions, whereas dark colourations may expand in regions where humidity is predicted to increase. Dark colouration may be also indirectly selected by climate warming because genes involved in the production of melanin pigments confer resistance to a number of stressful factors including those associated with climate warming. Furthermore, darker melanic individuals are commonly more aggressive than paler conspecifics, and hence they may better cope with competitive interactions due to invading species that expand their range in northern latitudes and at higher altitudes. To conclude, melanin may be a major component involved in adaptation to climate warming, and hence in animal populations melanin-based colouration is likely to change as an evolutionary or plastic response to climate warming.
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Intimal sarcoma (IS) is a rare, malignant, and aggressive tumor that shows a relentless course with a concomitant low survival rate and for which no effective treatment is available. In this study, 21 cases of large arterial blood vessel IS were analyzed by immunohistochemistry and fluorescence in situ hybridization and selectively by karyotyping, array comparative genomic hybridization, sequencing, phospho-kinase antibody arrays, and Western immunoblotting in search for novel diagnostic markers and potential molecular therapeutic targets. Ex vivo immunoassays were applied to test the sensitivity of IS primary tumor cells to the receptor tyrosine kinase (RTK) inhibitors imatinib and dasatinib. We showed that amplification of platelet-derived growth factor receptor α (PDGFRA) is a common finding in IS, which should be considered as a molecular hallmark of this entity. This amplification is consistently associated with PDGFRA activation. Furthermore, the tumors reveal persistent activation of the epidermal growth factor receptor (EGFR), concurrent to PDGFRA activation. Activated PDGFRA and EGFR frequently coexist with amplification and overexpression of the MDM2 oncogene. Ex vivo immunoassays on primary IS cells from one case showed the potency of dasatinib to inhibit PDGFRA and downstream signaling pathways. Our findings provide a rationale for investigating therapies that target PDGFRA, EGFR, or MDM2 in IS. Given the clonal heterogeneity of this tumor type and the potential cross-talk between the PDGFRA and EGFR signaling pathways, targeting multiple RTKs and aberrant downstream effectors might be required to improve the therapeutic outcome for patients with this disease.
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BACKGROUND Fragile X syndrome (FXS) is an inherited neurodevelopmental condition characterised by behavioural, learning disabilities, physical and neurological symptoms. In addition, an important degree of comorbidity with autism is also present. Considered a rare disorder affecting both genders, it first becomes apparent during childhood with displays of language delay and behavioural symptoms.Main aim: To show whether the combination of 10 mg/kg/day of ascorbic acid (vitamin C) and 10 mg/kg/day of α-tocopherol (vitamin E) reduces FXS symptoms among male patients ages 6 to 18 years compared to placebo treatment, as measured on the standardized rating scales at baseline, and after 12 and 24 weeks of treatment.Secondary aims: To assess the safety of the treatment. To describe behavioural and cognitive changes revealed by the Developmental Behaviour Checklist Short Form (DBC-P24) and the Wechsler Intelligence Scale for Children-Revised. To describe metabolic changes revealed by blood analysis. To measure treatment impact at home and in an academic environment. METHODS/DESIGN A phase II randomized, double-blind pilot clinical trial. SCOPE male children and adolescents diagnosed with FXS, in accordance with a standardized molecular biology test, who met all the inclusion criteria and none of the exclusion criteria. INSTRUMENTATION clinical data, blood analysis, Wechsler Intelligence Scale for Children-Revised, Conners parent and teacher rating scale scores and the DBC-P24 results will be obtained at the baseline (t0). Follow up examinations will take place at 12 weeks (t1) and 24 weeks (t2) of treatment. DISCUSSION A limited number of clinical trials have been carried out on children with FXS, but more are necessary as current treatment possibilities are insufficient and often provoke side effects. In the present study, we sought to overcome possible methodological problems by conducting a phase II pilot study in order to calculate the relevant statistical parameters and determine the safety of the proposed treatment. The results will provide evidence to improve hyperactivity control and reduce behavioural and learning problems using ascorbic acid (vitamin C) and α-tocopherol (vitamin E). The study protocol was approved by the Regional Government Committee for Clinical Trials in Andalusia and the Spanish agency for drugs and health products. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT01329770 (29 March 2011).
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BACKGROUND: Statins have been increasingly associated with drug-induced autoimmune reactions, including lupus erythematosus. OBJECTIVE: To identify and determine the clinical and biological characteristics of statin-induced autoimmune reactions. MATERIAL AND METHODS: The MEDLINE database (1966 to September 2005) was used to identify all reported cases of statin-induced autoimmune diseases. The keywords used were statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, adverse effects, autoimmune disease, lupus erythematosus, dermatomyositis and polymyositis. RESULTS: Twenty-eight cases of statin-induced autoimmune diseases have been published so far. Systemic lupus erythematosus was reported in 10 cases, subacute cutaneous lupus erythematosus in three cases, dermatomyositis and polymyositis in 14 cases and lichen planus pemphigoides in one case. Autoimmune hepatitis was observed in two patients with systemic lupus erythematosus. The mean time of exposure before disease onset was 12.8+/-18 months; range 1 month-6 years. Systemic immunosuppressive therapy was required in the majority of cases. In many patients, antinuclear antibodies were still positive many months after clinical recovery. A lethal outcome has been recorded in two patients despite aggressive immunosuppressive therapy. CONCLUSION: Long-term exposure to statins may be associated with drug-induced lupus erythematosus and other autoimmune disorders. Fatal cases have been reported despite early drug discontinuation and aggressive systemic immunosuppressive therapy.
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Y chromosome variation is determined by several confounding factors including mutation rate, effective population size, demography, and selection. Disentangling these factors is essential to better understand the evolutionary properties of the Y chromosome. We analyzed genetic variation on the Y chromosome, X chromosome, and mtDNA of the greater white-toothed shrew, a species with low variance in male reproductive success and limited sex-biased dispersal, which enables us to control to some extent for life-history effects. We also compared ancestral (Moroccan) to derived (European) populations to investigate the role of demographic history in determining Y variation. Recent colonization of Europe by a small number of founders (combined with low mutation rates) is largely responsible for low diversity observed on the European Y and X chromosomes compared to mtDNA. After accounting for mutation rate, copy number, and demography, the Y chromosome still displays a deficit in variation relative to the X in both populations. This is possibly influenced by directional selection, but the slightly higher variance in male reproductive success is also likely to play a role, even though the difference is small compared to that in highly polygynous species. This study illustrates that demography and life-history effects should be scrutinized before inferring strong selective pressure as a reason for low diversity on the Y chromosome.
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An 88 years old woman was admitted for muscular pain and weakness. She was under a treatment of simvastatin and was recently prescribed clarithromycin for a lung infection. The diagnosis of statin induced rhabdomyolysis by drug interaction was made. The evolution is good with eviction of the statin and aggressive hydratation. This case shows how important it is to know the risks factors and drug interactions predisposing to statin-induced myopathy.
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Peripheral T-cell lymphoma, not otherwise specified is a heterogeneous group of aggressive neoplasms with indistinct borders. By gene expression profiling we previously reported unsupervised clusters of peripheral T-cell lymphomas, not otherwise specified correlating with CD30 expression. In this work we extended the analysis of peripheral T-cell lymphoma molecular profiles to prototypical CD30(+) peripheral T-cell lymphomas (anaplastic large cell lymphomas), and validated mRNA expression profiles at the protein level. Existing transcriptomic datasets from peripheral T-cell lymphomas, not otherwise specified and anaplastic large cell lymphomas were reanalyzed. Twenty-one markers were selected for immunohistochemical validation on 80 peripheral T-cell lymphoma samples (not otherwise specified, CD30(+) and CD30(-); anaplastic large cell lymphomas, ALK(+) and ALK(-)), and differences between subgroups were assessed. Clinical follow-up was recorded. Compared to CD30(-) tumors, CD30(+) peripheral T-cell lymphomas, not otherwise specified were significantly enriched in ALK(-) anaplastic large cell lymphoma-related genes. By immunohistochemistry, CD30(+) peripheral T-cell lymphomas, not otherwise specified differed significantly from CD30(-) samples [down-regulated expression of T-cell receptor-associated proximal tyrosine kinases (Lck, Fyn, Itk) and of proteins involved in T-cell differentiation/activation (CD69, ICOS, CD52, NFATc2); upregulation of JunB and MUM1], while overlapping with anaplastic large cell lymphomas. CD30(-) peripheral T-cell lymphomas, not otherwise specified tended to have an inferior clinical outcome compared to the CD30(+) subgroups. In conclusion, we show molecular and phenotypic features common to CD30(+) peripheral T-cell lymphomas, and significant differences between CD30(-) and CD30(+) peripheral T-cell lymphomas, not otherwise specified, suggesting that CD30 expression might delineate two biologically distinct subgroups.
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Geography as a school subject is specifically thought for and by the schools. The contents of the school subject, nowadays, do not reflect the concerns and the evolution of the discipline as such. Nevertheless, official curricula set school objectives that address issues affecting the world and people's lives. These issues are coherent with the ones addressed by geography as a social science, that is to say the study of how people and their environment interact and how societies are interconnected through space. On an every day basis, Geography as a school subject is most of the time reduced to accumulating knowledge outside any given context. This knowledge may even be partially untrue or old and the related activities focus on low cognitive tensions. These practices do not contribute to the learners' understanding of the world because it does not allow them to build a geographical competence, which they. will need as future citizens in order to make responsible choices when they are confronted to questions related to how the locations of human and physical features are influenced by each other and how they interact across space. The central part of the text relies on the ideas and the processes discussed in the publications, which constitute the published file; it is divided into two parts. The first part (chapter 4) presents a didactic approach, which gives meaningful insights into Geography as a school subject and shows a brief account of the theoretical background that supports it. This socio-constructivist approach relies on the main following features: a priming stage (élément déclencheur), which presents geographical knowledge as an issue to be explored, discussed or solved; the issue is given to learners;. the planning of the teaching-learning sequence in small units launched by the main issue in the priming stage ; the interconnections of geographical knowledge with integrative concepts ; the synthetic stage or reporting stage where final concepts and knowledge are put together in order to be learned. Such an approach allows learners to re-invest the knowledge they have built themselves. This knowledge is organised by geographical integrative concepts, which represent true thinking operative tools and with which key issues in the geographical thinking are associated. The second part of the text (chapter 5) displays the didactic principles that governed the conception of the new initial training course for the future upper secondary school teachers at the HEP Vaud. The ambition of this course is to prepare future teachers to plan and realize the teaching of geography that provides pupils with the tools to understand better how people and their environment interact and how societies are interconnected through space. One of the tools for the teachers is the conceptual framework, whose most salient interest is to be relevant at every stage of the preparation and planning of the teaching, including the necessary epistemological reflection that should always be present. The synthesis of the text starts with a short account of the first evaluation of the new course. Various reflections on the future concerns and issues, that the didactics and methodology of Geography will be confronted with, constitute the synthesis.
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Median age at diagnosis in patients with glioblastoma (GB) is slowly increasing with an aging population in Western countries, and was 64years in 2006. The number of patients age 65 and older with GB will double in 2030 compared with 2000. Survival in this older cohort of patients is significantly less than seen in younger patients. This may in part be related to more aggressive biology of tumor, reduced use of standard management approaches, increased toxicity of available therapies, and increased presence of comorbidities in this older patient population. Limited data do support the use of more extensive resection in these patients. Randomized data support the use of post-operative radiotherapy (RT) versus supportive care, but do not demonstrate a benefit for the use of the standard 6weeks course of RT over hypofractionated RT given over 3weeks. Preliminary data of randomized studies raise the possibility of temozolomide alone as an option for these patients. The use of 6weeks of RT with concurrent and adjuvant temozolomide has been associated with reasonably good survival in several uncontrolled small series of selected older patients; however, this better outcome may be related to the selection of better prognosis patients rather than the specific therapy utilized. The current National Cancer Institute of Canada (NCIC) and European Organization for Research and Treatment of Cancer (EORTC) CE.6/26062/22061 randomized study of short course RT with or without concurrent and adjuvant temozolomide will help determine the optimal therapy for this older cohort with currently available therapies.
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Melanoma progression is associated with changes in adhesion receptor expression, in particular upregulation of N-cadherin which promotes melanoma cell survival and invasion. Plasma membrane lipid rafts contribute to the compartmentalization of signaling complexes thereby regulating their function, but how they may affect the properties of adhesion molecules remains elusive. In this study, we addressed the question whether lipid rafts in melanoma cells may contribute to the compartmentalization of N-cadherin. We show that a fraction of N-cadherin in a complex with catenins is associated with cholesterol/sphingolipid-rich membrane microdomains in aggressive melanoma cells in vitro and experimental melanomas in vivo. Partitioning of N-cadherin in membrane rafts is not modulated by growth factors and signaling pathways relevant to melanoma progression, is not necessary for cell-cell junctions' establishment or maintenance, and is not affected by cell-cell junctions' and actin cytoskeleton disruption. These results reveal that two independent pools of N-cadherin exist on melanoma cell surface: one pool is independent of lipid rafts and is engaged in cell-cell junctions, while a second pool is localized in membrane rafts and does not participate in cell-cell adhesions. Targeting to membrane rafts may represent a previously unrecognized mechanism regulating N-cadherin function in melanoma cells.
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Methadone is widely used for the treatment of opioid dependence. Although in most countries the drug is administered as a racemic mixture of (R)- and (S)- methadone, (R)-methadone accounts for most, if not all, of the opioid effects. Methadone can be detected in the blood 15-45 minutes after oral administration, with peak plasma concentration at 2.5-4 hours. Methadone has a mean bioavailability of around 75% (range 36-100%). Methadone is highly bound to plasma proteins, in particular to alpha(1)-acid glycoprotein. Its mean free fraction is around 13%, with a 4-fold interindividual variation. Its volume of distribution is about 4 L/kg (range 2-13 L/kg). The elimination of methadone is mediated by biotransformation, followed by renal and faecal excretion. Total body clearance is about 0.095 L/min, with wide interindividual variation (range 0.02-2 L/min). Plasma concentrations of methadone decrease in a biexponential manner, with a mean value of around 22 hours (range 5-130 hours) for elimination half-life. For the active (R)-enantiomer, mean values of around 40 hours have been determined. Cytochrome P450 (CYP) 3A4 and to a lesser extent 2D6 are probably the main isoforms involved in methadone metabolism. Rifampicin (rifampin), phenobarbital, phenytoin, carbamazepine, nevirapine, and efavirenz decrease methadone blood concentrations, probably by induction of CYP3A4 activity, which can result in severe withdrawal symptoms. Inhibitors of CYP3A4, such as fluconazole, and of CYP2D6, such as paroxetine, increase methadone blood concentrations. There is an up to 17-fold interindividual variation of methadone blood concentration for a given dosage, and interindividual variability of CYP enzymes accounts for a large part of this variation. Since methadone probably also displays large interindividual variability in its pharmacodynamics, methadone treatment must be individually adapted to each patient. Because of the high morbidity and mortality associated with opioid dependence, it is of major importance that methadone is used at an effective dosage in maintenance treatment: at least 60 mg/day, but typically 80-100 mg/day. Recent studies also show that a subset of patients might benefit from methadone dosages larger than 100 mg/day, many of them because of high clearance. In clinical management, medical evaluation of objective signs and subjective symptoms is sufficient for dosage titration in most patients. However, therapeutic drug monitoring can be useful in particular situations. In the case of non-response trough plasma concentrations of 400 microg/L for (R,S)-methadone or 250 microg/L for (R)-methadone might be used as target values.
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Background: Adenosquamous carcinoma (AC) of the head and neck is a distinct entity first described in 1968. Its natural history is more aggressive than squamous-cell carcinoma. The aim of this study was to assess the clinical profile, patterns of failure, and prognostic factors in patients with AC of the head and neck treated by radiation therapy (RT) with or without chemotherapy (CT).Materials and Methods: Data from 19 patients with stage I (n = 3), II (n = 1), III (n = 4), or IVa (n = 11) AC, treated between 1989 and 2009, were collected in a retrospective multicenter Rare Cancer Network study. Median age was 60 years (range, 48−73). Fifteen patients were male, and 4 female. Risk factors, including perineural invasion, lymphangitis, vascular invasion, positive margins were present in the majority (83%) of the patients. Tumour sites included oral cavity in 4, oropharynx in 4, hypopharynx in 2, larynx in 2, salivary glands in 2, nasal vestibule in 2, maxillary sinus in 2, and nasopharynx in 1 patient. Surgery (S) was performed in all but 5 patients. S alone was performed in only 1 patient, and definitive RT alone in 3 patients. Fifteen patients received combined modality treatment (S+RT in 11, RT+CT in 2, and all of the three modalities in 2 patients). Median RT dose to the primary and to the nodes was 66 Gy (range, 50−72) and 53 Gy (range, 44−66), respectively (1.8−2.0 Gy/fr., 5 fr./week). In 4 patients, the planning treatment volume included the primary tumour site only. Eight patients were treated with 2D RT, 7 with 3D conformal RT, and 2 with intensity-modulated RT.Results: After a median follow-up period of 39 months (range, 9−62), 9 patients developed distant metastases (lung, bone, mediastinum, and liver), 7 presented nodal recurrences, and only 4 had a local relapse at the primary site (all in-field recurrences). At last follow-up, 7 patients were alive without disease, 1 alive with disease, 9 died from progressive disease, and 2 died from intercurrent disease. The 3-year and median overall survival, disease-free survival (DFS), and locoregional control rates were 55% (95% confidence interval [CI]: 32−78%) and 39 months, 34% (95% CI: 12−56%) and 22 months, and 50% (95% CI: 22−78%) and 33 months, respectively. In multivariate analysis (Cox model), DFS was negatively influenced by the presence of extracapsular extension (p = 0.01) and advanced stage (IV versus I−III, p = 0.002).Conclusions: Overall prognosis of locoregionally advanced AC remains poor, and distant metastases and nodal relapse occur in almost half of the cases. However, local control is relatively better, and early stage AC patients had prolonged DFS when treated with combined-modality treatment.
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BACKGROUND/AIMS: Treatment of chronic HCV infection has become a priority in HIV+ patients, given the faster progression to end-stage liver disease. The primary endpoint of this study was to evaluate and compare antiviral efficacy of Peginterferon alpha 2a plus ribavirin in HIV-HCV co-infected and HCV mono-infected patients, and to examine whether 6 months of therapy would have the same efficacy in HIV patients with favourable genotypes 2 and 3 as in mono-infected patients, to minimise HCV-therapy-related toxicities. Secondary endpoints were to evaluate predictors of sustained virological response (SVR) and frequency of side-effects. METHODS: Patients with genotypes 1 and 4 were treated for 48 weeks with Pegasys 180 microg/week plus Copegus 1000-1200 mg/day according to body weight; patients with genotypes 2 and 3 for 24 weeks with Pegasys 180 microg/week plus Copegus 800 mg/day. RESULTS: 132 patients were enrolled in the study: 85 HCV mono-infected (38: genotypes 1 and 4; 47: genotypes 2 and 3), 47 HIV-HCV co-infected patients (23: genotypes 1 and 4; 24: genotypes 2 and 3). In an intention-to-treat analysis, SVR for genotypes 1 and 4 was observed in 58% of HCV mono-infected and in 13% of HIV-HCV co-infected patients (P = 0.001). For genotypes 2 and 3, SVR was observed in 70% of HCV mono-infected and in 67% of HIV-HCV co-infected patients (P = 0.973). Undetectable HCV-RNA at week 4 had a positive predictive value for SVR for mono-infected patients with genotypes 1 and 4 of 0.78 (95% CI: 0.54-0.93) and of 0.81 (95% CI: 0.64-0.92) for genotypes 2 and 3. For co-infected patients with genotypes 2 and 3, the positive predictive value of SVR of undetectable HCV-RNA at week 4 was 0.76 (95%CI, 0.50-0.93). Study not completed by 22 patients (36%): genotypes 1 and 4 and by 12 patients (17%): genotypes 2 and 3. CONCLUSION: Genotypes 2 or 3 predict the likelihood of SVR in HCV mono-infected and in HIV-HCV co-infected patients. A 6-month treatment with Peginterferon alpha 2a plus ribavirin has the same efficacy in HIV-HCV co-infected patients with genotypes 2 and 3 as in mono-infected patients. HCV-RNA negativity at 4 weeks has a positive predictive value for SVR. Aggressive treatment of adverse effects to avoid dose reduction, consent withdrawal or drop-out is crucial to increase the rate of SVR, especially when duration of treatment is 48 weeks. Sixty-one percent of HIV-HCV co-infected patients with genotypes 1 and 4 did not complete the study against 4% with genotypes 2 and 3.
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We report a newborn with respiratory distress and situs inversus totalis. The diagnosis of primary ciliary dyskinesia was confirmed by both ultrastructural and functional investigations. The immotile cilia syndrome was suspected because of respiratory distress, situs inversus, abnormal nasal discharge and hyperinflated chest X-ray. We suggest that ultrastructural and functional investigations of the respiratory mucosa should be done in any newborn with respiratory distress without explanation for the respiratory problems. Establishment of the correct diagnosis at an early stage may allow to improve the prognosis provided prophylactic physiotherapy, vaccinations, and aggressive antibiotic treatment of intercurrent respiratory infections are instituted. CONCLUSION Despite its rarity, primary ciliary dyskinesia should be considered in unexplained cases of neonatal distress.