933 resultados para mortality and survival for the four most common cancers


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BACKGROUND AND PURPOSE: Identification of the population at risk of stroke remains the best approach to assess the burden of cardiovascular morbidity and mortality. METHODS: The prevalence of hypertension (HT), hypercholesterolemia (HCh), diabetes mellitus (DM), overweight (OW), obesity (OB), tobacco use (SM), and their combinations was examined in 4,458 Swiss persons (1,741 men and 2,717 women, mean age 57.8 +/- 15 years), who volunteered for the present survey. RESULTS: OW was the most prevalent risk factor (50 %), followed by HT (47%), HCh (33%), SM (13 %) and DM (1.6 %). The proportion of persons without risk factors (RF) was 19.9%, with 1 RF 41.5%, 2 RF 33.8%, 3 RF 4%, and 4 RF 0.9%. OW was more prevalent in men than in women (53% vs. 41%, P=0.02). More men than women aged 41-50 years and 51-60 years had HT (49 % vs. 36%, P=0.01, and 52 % vs. 42%, P=0.02). The prevalence of HCh and DM did not show any sex-related differences. HT, OW and HCh were not only the most common single risk factors, but were also most likely to aggregate with each other. CONCLUSIONS: The majority of Swiss people have one or two vascular risk factors. OW and HT are by far most common and are likely to aggregate with each other. A small modification of these two factors would reduce the incidence of stroke and myocardial infarction significantly.

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The morphological characterisation of the western submarine island flanks of El Hierro and La Palma differentiates four type-zones that may give new insights into the evolution of oceanic island slopes. The different type-zones result from the interplay between constructive volcanic processes, hemipelagic settling and volcano collapses. The latter results in massive debris avalanche deposits, which form large volcaniclastic aprons. In most cases, the headwall scarps are clearly exposed on the emerged part of the islands. The events that occurred in the youngest and westernmost islands of El Hierro and La Palma have vertical runouts exceeding 6,000 m and volumes that can reach several hundred km3. The landslide frequency for the entire Canaries is one major event per 90 ka. Triggering mechanisms are closely related to magmatic processes. The increase in the shear stress is directly linked with the forceful intrusion of magma along ridge-rift systems, while in the western Canary Islands it seems that the main process reducing shear resistance may be related to the rise in pore pressure due to hydrothermal circulation.

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The aim of this study was to identify genes involved in solute and matric stress mitigation in the polycyclic aromatic hydrocarbon (PAH)-degrading Novosphingobium sp. strain LH128. The genes were identified using plasposon mutagenesis and by selection of mutants that showed impaired growth in a medium containing 450 mM NaCl as a solute stress or 10% (wt/vol) polyethylene glycol (PEG) 6000 as a matric stress. Eleven and 14 mutants showed growth impairment when exposed to solute and matric stresses, respectively. The disrupted sequences were mapped on a draft genome sequence of strain LH128, and the corresponding gene functions were predicted. None of them were shared between solute and matric stress-impacted mutants. One NaCl-affected mutant (i.e., NA7E1) with a disruption in a gene encoding a putative outer membrane protein (OpsA) was susceptible to lower NaCl concentrations than the other mutants. The growth of NA7E1 was impacted by other ions and nonionic solutes and by sodium dodecyl sulfate (SDS), suggesting that opsA is involved in osmotic stress mitigation and/or outer membrane stability in strain LH128. NA7E1 was also the only mutant that showed reduced growth and less-efficient phenanthrene degradation in soil compared to the wild type. Moreover, the survival of NA7E1 in soil decreased significantly when the moisture content was decreased but was unaffected when soluble solutes from sandy soil were removed by washing. opsA appears to be important for the survival of strain LH128 in soil, especially in the case of reduced moisture content, probably by mitigating the effects of solute stress and retaining membrane stability.

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Rice in Rio Grande do Sul State is grown mostly under flooding, which induces a series of chemical, physical and biological changes in the root environment. These changes, combined with the presence of rice plants, affect the availability of exchangeable ammonium (NH4+) and pH of soil solution, whereas the dynamics of both variables can be influenced by soil salinity, a common problem in the coastal region. This study was conducted to evaluate the dynamics of exchangeable NH4+ and pH in the soil solution, and their relation in the solution of Albaqualf soils with different salinity levels, under rice. Four field experiments were conducted with soils with exchangeable Na percentage (ESP) of 5.6, 9.0, 21.2, and 32.7 %. Prior to flooding, soil solution collectors were installed at depths of 5, 10 and 20 cm. The soil solution was collected weekly, from 7 to 91 days after flooding (DAF), to analyze exchangeable NH4+ and pH in the samples. Plant tissue was sampled 77 DAF, to determine N uptake and estimate the contribution of other N forms to rice nutrition. The content of exchangeable NH4+ decreased over time at all sites and depths, with a more pronounced reduction in soils with lower salinity levels, reaching values close to zero. A possible contribution of non-exchangeable NH4+ forms and N from soil organic matter to rice nutrition was observed. Soil pH decreased with time in soils with ESP 5.6 and 9.0 %, being positively correlated with the decreasing NH4+ levels at these sites.

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With the aging population and its rapidly increasing prevalence, dementia has become an important public health concern in developed and developing countries. To date, the pharmacological treatment is symptomatic and based on the observed neurotransmitter disturbances. The four most commonly used drugs are donepezil, galantamine, rivastigmine and memantine. Donepezil, galantamine and rivastigmine are acetylcholinesterase inhibitors with different pharmacodynamic and pharmacokinetic profiles. Donepezil inhibits selectively the acetylcholinesterase and has a long elimination half-life (t½) of 70 h. Galantamine is also a selective acetylcholinesterase inhibitor, but also modulates presynaptic nicotinic receptors. It has a t½ of 6-8 h. Donepezil and galantamine are mainly metabolised by cytochrome P450 (CYP) 2D6 and CYP3A4 in the liver. Rivastigmine is a so-called 'pseudo-irreversible' inhibitor of acetylcholinesterase and butyrylcholinesterase. The t½ of the drug is very short (1-2 h), but the duration of action is longer as the enzymes are blocked for around 8.5 and 3.5 h, respectively. Rivastigmine is metabolised by esterases in liver and intestine. Memantine is a non-competitive low-affinity antagonist of the NMDA receptor with a t½ of 70 h. Its major route of elimination is unchanged via the kidneys. Addressing the issue of inter-patient variability in treatment response might be of special importance for the vulnerable population taking anti-dementia drugs. Pharmacogenetic considerations might help to avoid multiple medication changes due to non-response and/or adverse events. Some pharmacogenetic studies conducted on donepezil and galantamine reported an influence of the CYP2D6 genotype on the pharmacokinetics of the drugs and/or on the response to treatment. Moreover, polymorphisms in genes of the cholinergic markers acetylcholinesterase, butyrylcholinesterase, choline acetyltransferase and paraoxonase were found to be associated with better clinical response to acetylcholinesterase inhibitors. However, confirmation studies in larger populations are necessary to establish evidence of which subgroups of patients will most likely benefit from anti-dementia drugs. The aim of this review is to summarize the pharmacodynamics and pharmacokinetics of the four commonly used anti-dementia drugs and to give an overview on the current knowledge of pharmacogenetics in this field.

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The Monte San Giorgio (Southern Alps, Ticino, Switzerland) is the most important locality in the world for vertebrates dating back to the Middle Triassic. For this reason it was registered in 2003 as a UNESCO World Heritage Site. One of the objectives of this doctoral thesis was to fill some of the cognitive gaps regarding the Ladinian succession, including in particular the San Giorgio Dolomite and the Meride Limestone. In order to achieve this, the entire succession, more than 600 metres thick, was measured and sampled. Biostratigraphic research based on new finds of fossil invertebrates and microfossils and on the palynological analysis of the entire section was integrated with single-zircon U-Pb dating of volcanic ash layers intercalated in the carbonate succession. This enabled a redefinition of the bio-chronostratigraphic and geochronologic framework of the succession, which encompasses a significantly shorter time interval than previously held. The Ladinian section extends from the E. curionii Ammonoid Zone (Early Fassanian) to the P. archelaus Ammonoid Zone (Early Longobardian). The age of the classic fossiliferous levels of the Meride Limestone, rich in organic matter and containing vertebrate fossils which are known all over the world, was defined in both biostratigraphic and geochronologic terms. The presumed stratigraphie significance of the pachypleurosaurid reptiles found in such levels is called into question by new finds. These fossiliferous horizons were found to correspond to the main volcanoclastic intervals of the Buchenstein Formation (Middle and Upper Pietra Verde). Thus, a correlation with the Bagolino Section (Italy) containing the GSSP for the base of the Ladinian was proposed. Bulk sedimentation rates in the studied succession average 200 m/Myr and therefore prove to be 20 times higher than those of the South-Alpine pelagic basins. These values express high carbonate productivity from the surrounding platforms on one hand, and on the other a marked subsidence of the basin. Only in the intervals consisting of laminated limestones did the sedimentation rates drop to average values of around 30 m/Myr. The distribution of organic and inorganic facies appears to be the consequence of relative variations in sea-level. The laminated and organic-matter- rich intervals of the Meride Limestone are linked to a relative sea-level drop which favoured dysoxic to anoxic bottom-water conditions, coupled with an increase in runoff, perhaps due to recurrent explosive volcanic activity. The transient development under dysoxic conditions of monospecific benthic meio-/macrofaunas was documented. Organic matter suggests a predominant origin due to benthic bacterial activity, as can be witnessed in alveolar structures typical of exopolymeric substances secreted by bacteria within microbial mats. A microbial contribution to the carbonate (peloidal) precipitation was documented. The protective effect exerted by these microbial mats is also indicated as the main taphonomic factor contributing to the excellent preservation of vertebrate fossils. A radiolarian assemblage discovered in the lower part of the section (earliest Ladinian, E. curionii Zone) suggests the transient existence of open-marine but not deep-water connections with the tethyan pelagic basins. It shows marked similarities to the faunas typical of the late Anisian, suggesting therefore a low resolution power provided by radiolarian biostratigraphy in recognizing the Anisian/Ladinian boundary. The present thesis describes a new species of conifer (Elatocladus cassinae), a new species of insect (Dasyleptus triassicus) and seven new species of radiolarians (Eptingium danieli, Eptingium neriae, Parentactinosphaera eoladinica, Sepsagon ticinensis, Sepsagon? valporinae, Novamuria wirzi and Pessagnollum? hexaspinosum). In addition, following revision of the type material of already existent taxa, four new genera of radiolarians are introduced: Bernoulliella, Eohexastylus, Ticinosphaera and Lahmosphaera.

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Background: In insects, like in most invertebrates, olfaction is the principal sensory modality, which provides animals with essential information for survival and reproduction. Odorant receptors are involved in this response, mediating interactions between an individual and its environment, as well as between individuals of the same or different species. The adaptive importance of odorant receptors renders them good candidates for having their variation shaped by natural selection. Methodology/Principal Findings: We analyzed nucleotide variation in a subset of eight Or genes located on the 3L chromosomal arm of Drosophila melanogaster in a derived population of this species and also in a population of Drosophila pseudoobscura. Some heterogeneity in the silent polymorphism to divergence ratio was detected in the D. melanogaster/D. simulans comparison, with a single gene (Or67b) contributing ~37% to the test statistic. However, no other signals of a very recent selective event were detected at this gene. In contrast, at the speciation timescale, the MK test uncovered the footprint of positive selection driving the evolution of two of the encoded proteins in both D. melanogaster ¿OR65c and OR67a ¿and D. pseudoobscura ¿OR65b1 and OR67c. Conclusions: The powerful polymorphism/divergence approach provided evidence for adaptive evolution at a rather high proportion of the Or genes studied after relatively recent speciation events. It did not provide, however, clear evidence for very recent selective events in either D. melanogaster or D. pseudoobscura.

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Rate of metabolism and body temperature were studied between -6°C and 38°C in the common pipistrelle bat Pipistrellus pipistrellus (Vespertilionidae), a European species lying close to the lower end of the mammalian size range (body mass 4.9±0.8g, N=28). Individuals maintained only occasionally a normothermic body temperature averaging 35.4±1.1°C (N=4) and often showed torpor during metabolic runs. The thermoneutral zone was found above 33°C, and basal rate of metabolism averaged 7.6±0.8mL O(2)h(-1) (N=28), which is 69% of the value predicted on the basis of body mass. Minimal wet thermal conductance was 161% of the expected value. During torpor, the rate of metabolism was related exponentially to body temperature with a Q(10) value of 2.57. Torpid bats showed intermittent ventilation, with the frequency of ventilatory cycles increasing exponentially with body temperature. Basal rate of metabolism (BMR) varied significantly with season and body temperature, but not with body mass. It was lower before the hibernation period than during the summer. The patterns observed are generally consistent with those exhibited by other vespertilionids of temperate regions. However, divergences occur with previous measurements on European pipistrelles, and the causes of the seasonal variation in BMR, which has only rarely been searched for among vespertilionids, remain to be examined.

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Here we discuss life-history evolution from the perspective of adaptive phenotypic plasticity, with a focus on polyphenisms for somatic maintenance and survival. Polyphenisms are adaptive discrete alternative phenotypes that develop in response to changes in the environment. We suggest that dauer larval diapause and its associated adult phenotypes in the nematode (Caenorhabditis elegans), reproductive dormancy in the fruit fly (Drosophila melanogaster) and other insects, and the worker castes of the honey bee (Apis mellifera) are examples of what may be viewed as the polyphenic regulation of somatic maintenance and survival. In these and other cases, the same genotype can--depending upon its environment--express either of two alternative sets of life-history phenotypes that differ markedly with respect to somatic maintenance, survival ability, and thus life span. This plastic modulation of somatic maintenance and survival has traditionally been underappreciated by researchers working on aging and life history. We review the current evidence for such adaptive life-history switches and their molecular regulation and suggest that they are caused by temporally and/or spatially varying, stressful environments that impose diversifying selection, thereby favoring the evolution of plasticity of somatic maintenance and survival under strong regulatory control. By considering somatic maintenance and survivorship from the perspective of adaptive life-history switches, we may gain novel insights into the mechanisms and evolution of aging.

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How phenomena like helping, dispersal, or the sex ratio evolve depends critically on demographic and life-history factors. One phenotype that is of particular interest to biologists is genomic imprinting, which results in parent-of-origin-specific gene expression and thus deviates from the predictions of Mendel's rules. The most prominent explanation for the evolution of genomic imprinting, the kinship theory, originally specified that multiple paternity can cause the evolution of imprinting when offspring affect maternal resource provisioning. Most models of the kinship theory do not detail how population subdivision, demography, and life history affect the evolution of imprinting. In this work, we embed the classic kinship theory within an island model of population structure and allow for diverse demographic and life-history features to affect the direction of selection on imprinting. We find that population structure does not change how multiple paternity affects the evolution of imprinting under the classic kinship theory. However, if the degree of multiple paternity is not too large, we find that sex-specific migration and survival and generation overlap are the primary factors determining which allele is silenced. This indicates that imprinting can evolve purely as a result of sex-related asymmetries in the demographic structure or life history of a species.

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Anti-angiogenic therapies have recently enriched the therapeutic armentarium against the most common cancers. Among these, bevacizumab, a monoclonal antibody against vascular endothelial growth factor, is currently used most frequently. While the addition of bevacizumab to chemotherapy improves overall survival in first and second line treatment of metastatic colorectal cancer, its effect in metastatic breast cancer is limited to improvements in tumor response and progression-free-survival. In non-small-cell lung cancer, the positive results of a first American phase III study have not been confirmed by a second European study and are subject to controversies. A summary of the data concerning anti-angiogenic therapies in these three cancers is presented including safety information.

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Myc activity is emerging as a key element in acquisition and maintenance of stem cell properties. We have previously shown that c-Myc deficiency results in accumulation of defective hematopoietic stem cells (HSCs) due to niche-dependent differentiation defects. Here we report that immature HSCs coexpress c-myc and N-myc mRNA at similar levels. Although conditional deletion of N-myc in the bone marrow does not affect hematopoiesis, combined deficiency of c-Myc and N-Myc (dKO) results in pancytopenia and rapid lethality. Interestingly, proliferation of HSCs depends on both myc genes during homeostasis, but is c-Myc/N-Myc independent during bone marrow repair after injury. Strikingly, while most dKO hematopoietic cells undergo apoptosis, only self-renewing HSCs accumulate the cytotoxic molecule Granzyme B, normally employed by the innate immune system, thereby revealing an unexpected mechanism of stem cell apoptosis. Collectively, Myc activity (c-Myc and N-Myc) controls crucial aspects of HSC function including proliferation, differentiation, and survival.

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α-Crystallins, initially described as the major structural proteins of the lens, belong to the small heat shock protein family. Apart from their function as chaperones, α-crystallins are involved in the regulation of intracellular apoptotic signals. αA- and αB-crystallins have been shown to interfere with the mitochondrial apoptotic pathway triggering Bax pro-apoptotic activity and downstream activation of effector caspases. Differential regulation of α-crystallins has been observed in several eye diseases such as age-related macular degeneration and stress-induced and inherited retinal degenerations. Although the function of α-crystallins in healthy and diseased retina remains poorly understood, their altered expression in pathological conditions argue in favor of a role in cellular defensive response. In the Rpe65(-/-) mouse model of Leber's congenital amaurosis, we previously observed decreased expression of αA- and αB-crystallins during disease progression, which was correlated with Bax pro-death activity and photoreceptor apoptosis. In the present study, we demonstrated that α-crystallins interacted with pro-apoptotic Bax and displayed cytoprotective action against Bax-triggered apoptosis, as assessed by TUNEL and caspase assays. We further observed in staurosporine-treated photoreceptor-like 661W cells stably overexpressing αA- or αB-crystallin that Bax-dependent apoptosis and caspase activation were inhibited. Finally, we reported that the C-terminal extension domain of αA-crystallin was sufficient to provide protection against Bax-triggered apoptosis. Altogether, these data suggest that α-crystallins interfere with Bax-induced apoptosis in several cell types, including the cone-derived 661W cells. They further suggest that αA-crystallin-derived peptides might be sufficient to promote cytoprotective action in response to apoptotic cell death.

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Purpose: The retinal balance between pro- and anti-angiogenic factors is critical for angiogenesis control, but is also involved in cell survival. We previously reported upregulation of VEGF and photoreceptor (PR) cell death in the Light-damage (LD) model. Preliminary results showed that anti-VEGF can rescue PR from cell death. Thus, we investigated the role of VEGF on the retina and we herein described the effect of anti-VEGF antibody delivered by lentiviral gene transfer in this model.Methods: To characterize the action of VEGF during the LD, we exposed Balb/c mice subretinally injected with LV-anti-VEGF, or not, to 5'000 lux for 1h. We next evaluated the retinal function, PR survival and protein expression (VEGF, VEGFR1/2, Src, PEDF, p38MAPK, Akt, Peripherin, SWL-opsin) after LD. We analyzed Blood retinal barrier (BRB) integrity on flat-mounted RPE and cryosections stained with β-catenin, ZO-1, N-cadherin and albumin.Results: Results indicate that the VEGF pathway is modulated after LD. LD leads to extravascular albumin leakage and BRB breakdown: β-catenin, ZO-1 and N-cadherin translocate to the cytoplasm of RPE cells showing loss of cell cohesion. This phenomenon is in adequacy with the VEGF time-course expression. Assessment of the retinal function reveals that PR rescue correlates with the level of LV-anti-VEGF expression. Rhodopsin content was higher in the LV-anti-VEGF group than in controls and measures of the ONL thickness indicate that LV-anti-VEGF preserves by 82% the outer nuclear layer from degeneration. Outer segments (OS) appeared well organized with an appropriate length in the LV-anti-VEGF group compared to controls, and the expression of SWL-opsin is maintained in the OS without being mislocalized as in the LV-GFP group. Finally, LV-anti-VEGF treatment prevents BRB breakdown and maintained RPE cell integrity.Conclusions: This study involves VEGF in LD and highlights the prime importance of the BRB integrity for PR survival. Taken together, these results show that anti-VEGF is neuroprotective in this model and maintains functional PR layer in LD-treated mice.

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PURPOSE: To analyze available evidence on the incidence of anatomical variations or disease of the maxillary sinuses as identified by cone beam computed tomography (CBCT) in dentistry. MATERIALS AND METHODS: A focused question was developed to search the electronic databases MEDLINE, EMBASE, the Cochrane Oral Health Group Trials Register, and CENTRAL and identify all relevant papers published between 1980 and January 19, 2013. Unpublished literature at ClinicalTrials.gov, in the National Research Register, and in the Pro-Quest Dissertation Abstracts and Thesis database was also included. Studies were included irrespective of language. These results were supplemented by hand and gray literature searches. RESULTS: Twenty-two studies were identified. Twenty were retrospective cohort studies, one was a prospective cohort study, and one was a case control study. The main indication for CBCT was dental implant treatment planning, and the majority of studies used a small field of view for imaging. The most common anatomical variations included increased thickness of the sinus membrane, the presence of sinus septa, and pneumatization. Reported sinus disease frequency varied widely, ranging from 14.3% to 82%. There was a wide range in the reported prevalence of mucosal thickening related to apical pathology, the degree of lumenal opacification, features of sinusitis, and the presence of retention cysts and polyps. More pathologic findings in the maxillary sinus were reported in men than in women, and the medial wall and sinus floor were most frequently affected. CONCLUSION: CBCT is used primarily to evaluate bony anatomy and to screen for overt pathology of the maxillary sinuses prior to dental implant treatment. Differences in the classification of mucosal findings are problematic in the consistent and valid assessment of health and disease of the maxillary sinus.