335 resultados para anti-angiogenesis
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Background and Aims: The three anti-TNF agents infliximab (IFX), adalimumab (ADA) andcertolizumab pegol (CZP) have demonstrated similar efficacy in induction and maintenanceof response and remission in Crohn's disease (CD) treatment. Given the comparability ofthese drugs, patient's preferences may influence the choice of the product. However, dataon patient's preferences for choosing anti-TNF agents are lacking. We therefore aimed toassess the CD patient's appraisal to select the drug of his choice and to identify factorsguiding this decision.Methods: A prospective survey among anti-TNF-naive CD patientswas performed. Patients were provided a description of the three anti-TNF agents focusingon indication, application mode (s.c. vs. i.v.), application time intervals, setting of application(hospital vs. private practice vs. patient's home), average time to apply the medication permonth, typical side effects, and the scientific evidence of efficacy and safety available for everydrug. Patients answered a questionnaire consisting of 17 questions, covering demographic,disease-specific, and medication data.Results: Hundred patients (47f/53m, mean age 45±16years) completed the questionnaire. Disease duration was <1year in 7%, 1-5 years in 31%,and >5 years in 62% of patients. Disease location was ileal in 33%, colonic in 40%, andileocolonic in 27%. Disease phenotype was inflammatory in 68%, stenosing in 29%, andinternally fistulizing in 3% of patients. Additionally, 20% had perianal fistulizing disease.Patients were already treated with the following drugs: mesalamines 61%, budesonide 44%,prednisone 97%, thiopurines 78%, methotrexate 16%. In total, 30% had already heardabout IFX, 20% about ADA, and 11% about CZP. Thirty-six percent voted for treatmentwith ADA, 28% for CZP, and 25% for IFX, whereas 11% were undecided. The followingfactors influenced the patient's decision for choosing a specific anti-TNF drug (severalanswers possible): side effects 76%, physician's recommendation 66%, application mode54%, efficacy experience 52%, time to spend for therapy 27%, patient's recommendations21%, interactions with other medications 12%. The single most important factor for choosinga specific anti-TNF was (1 answer): side effect profile 35%, physician's recommendation22%, efficacy experience 21%, application mode 13%, patient's recommendations 5%, timespent for therapy 3%, interaction with other medications 1%.Conclusions: The majority ofpatients preferred anti-TNF syringes to infusions. The safety profile of the drugs and thephysician's recommendation are major factors influencing the patient's choice for a specificanti-TNF drug. Patient's issues about safety and lifestyle habits should be taken into accountwhen prescribing specific anti-TNF formulations.
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Age related macular degeneration (AMD) is an ocular disease with high prevalence among elderly persons. Two different forms exist: dry AMD, usually slowly progressive, and neovascular AMD (wet form) more aggressive. Photodynamic therapy is used to treat the wet form and anti VEGF treatments recently became available and offer a real change in the prognostic of wet AMD. Two products are registered and used in Switzerland (Macugen and Lucentis), a third "off labels product", Avastin is also currently used in clinical practice. Nevertheless, both the duration of treatment and the number of injection requested to stabilise the disease were not defined in the studies. Ongoing studies are mainly evaluating combined treatments and long acting form of the drug.
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Abstract: Blocking tumor growth by targeting the tumor vasculature is a promising approach in cancer therapy. Both, disrupting tumor vessels as well as normalization of tumor vessel abnormalities have shown anti-cancer efficacy. A plethora of agents that act on the tumor vasculature have been developed; however, so far few have shown clinical benefits. Among the successful agents, inhibitors of the mammalian target of rapamycin (mTOR) are able to reduce tumor growth by targeting tumor vessels. mTOR inhibition exerts at least three different effects on the tumor vasculature. First, it reduces tumor angiogenesis. Second it normalizes the tumor vasculature and third, it promotes the formation of thrombosis in tumor vessels. The characterization of the molecular functions regulated by mTOR and of relevance to the tumor vasculature is therefore important in order to further identify biological mechanisms involved in the tumor vascular network as well as to improve the efficacy of these inhibitors. Here, we will first enumerate the evidences for the anti-angiogenic activities of mTOR inhibitors and describe the molecular mechanisms involved. We will further analyze the effects of mTOR inhibition on vascular normalization and also describe how mTOR inhibition promotes thrombosis formation specifically in tumor vessels. Finally, we will describe a new generation of mTOR inhibitors and examine their effects on the tumor vasculature
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Glioblastoma multiforme (GBM) is the most malignant variant of human glial tumors. A prominent feature of this tumor is the occurrence of necrosis and vascular proliferation. The regulation of glial neovascularization is still poorly understood and the characterization of factors involved in this process is of major clinical interest. Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine released by leukocytes and by a variety of cells outside of the immune system. Recent work has shown that MIF may function to regulate cellular differentiation and proliferation in normal and tumor-derived cell lines, and may also contribute to the neovascularization of tumors. Our immunohistological analysis of MIF distribution in GBM tissues revealed the strong MIF protein accumulation in close association with necrotic areas and in tumor cells surrounding blood vessels. In addition, MIF expression was frequently associated with the presence of the tumor-suppressor gene p53. To substantiate the concept that MIF might be involved in the regulation of angiogenesis in GBM, we analyzed the MIF gene and protein expression under hypoxic and hypoglycemic stress conditions in vitro. Northern blot analysis showed a clear increase of MIF mRNA after hypoxia and hypoglycemia. We could also demonstrate that the increase of MIF transcripts on hypoxic stress can be explained by a profound transcriptional activation of the MIF gene. In parallel to the increase of MIF transcripts, we observed a significant rise in extracellular MIF protein on angiogenic stimulation. The data of our preliminary study suggest that the up-regulation of MIF expression during hypoxic and hypoglycemic stress might play a critical role for the neovascularization of glial tumors.
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Right ventricular and left ventricular systolic time intervals (RVSTIs and LVSTIs) were measured in normal term and preterm infants from 1 hour to 90 days of life. LVSTIs in both term and preterm infants were similar in the first five days of life. The ratio of left pre-ejection period (LPEP) to left ventricular ejection time (LVET) was lower in preterm infants older than age 5 days. Estimated gestational age had no influence on LVSTI. The ratio of right pre-ejection period (RPEP) to right ventricular ejection time (RVET) was lower in preterm infants (0.32) than in term newborns (0.37). The preterm RPEP/RVET ratio decreased with age, but at a slower rate than in term babies. This was consistent with the lower pulmonary vascular resistance present in preterm infants.
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Growing evidence suggests that the patient's immune response may play a major role in the long-term efficacy of antibody therapies of follicular lymphoma (FL). Particular long-lasting recurrence free survivals have been observed after first line, single agent rituximab or after radioimmunotherapy (RIT). Rituximab maintenance, furthermore, has a major efficacy in prolonging recurrence free survival after chemotherapy. On the other hand, RIT as a single step treatment showed a remarkable capacity to induce complete and partial remissions when applied in recurrence and as initial treatment of FL or given for consolidation. These clinical results strongly suggest that RIT combined with rituximab maintenance could stabilize the high percentages of patients with CR and PR induced by RIT. While the precise mechanisms of the long-term efficacy of these 2 treatments are not elucidated, different observations suggest that the patient's T cell immune response could be decisive. With this review, we discuss the potential role of the patient's immune system under rituximab and RIT and argue that the T cell immunity might be particularly promoted when combining the 2 antibody treatments in the early therapy of FL.
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The Jbel Saghro alkaline complex was emplaced close to the eastern edge of the Moroccan Anti-Atlas. Within the northern part, two types of nephelinite were recognized [Ibhi and Nachit, 1999 and lbhi, 2000]. The first type (olivine-rich nephelinite) constitutes the main volcanic mass south of the Bou Gafer granit (fig. 1), where the volcanism had been active at least during 2 Ma, between 9.6 and 7.5 +/- 0.1 Ma [Berrahma et al., 1993]. The second group outcrops in the north (Foum El Kouss). It consists of pyroxene nephelinites which are younger (2.9 +/- 0.1 Ma) [Berrahma et al., 1993], and bears carbonatitic xenoliths, melteigitic pyroxenites and metasomatised peridotite xenoliths. Geochemically, the pyroxene nephelinite is highly enriched in LILE compared with the first one. The mineralogical and geochemical characteristics may be explained by the incorporation of carbonatitic and melteigitic pyroxenite segregates of carbonatitic affinity.
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Introduction: Small for gestational age (SGA) is an important problem affecting 10% of pregnancies and is associated with significant perinatal morbidity. In about 80% of cases, a probable etiology or a major risk factor can be identified. But almost 20% of SGA cases are considered unexplained. The 60-kDa heat shock protein (HSP60) is a highly immunogenic protein whose synthesis is greatly upregulated under nonphysiological conditions. Bacterial and human HSP60 share a high degree of sequence homology, and immunity to conserved epitopes may result in development of autoimmunity following a bacterial infection. We hypothesized that unexplained SGA could be the consequence of immune sensitization to human HSP60. Methods: Unexplained SGA fetuses were identified by ultrasound biometry with normal Doppler velocimetry and with no detectable maternal or fetal abnormalities. Fetal sera were obtained by cordocentesis performed for a karyotype analysis in cases of unexplained SGA (study group) or for screening of Rhesus incompatibility (control group). Fetal sera were tested for HSP60 antigen and for IgG and IgM anti-HSP60 by ELISA as well as for other immune and hematological parameters. Results: Maternal parameters were similar between the 12 study cases and the 23 control cases. The mean gestational age at cordocentesis was 29 weeks. IgM anti-HSP60 was detected in 12 cases (100%) and in no controls (p < 0.00017), while IgG anti-HSP60 was detected in 7 cases (58%) and only 1 control (p < 0.001). Three of the 4 cases with the highest IgM antibody levels died. There were no differences in fetal serum levels of HSP60 antigen or other immune and hematological markers between the two groups. Conclusion: Fetuses with unexplained SGA are positive for IgM and IgG antibody to human HSP60 and the specific IgM antibody level is predictive of fetal mortality. Detection of these antibodies indicates that a placental perturbation and a fetal autoimmune reaction to HSP60 are associated with this developmental delay.
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Cooperation in joint enterprises can easily break down when self-interests are in conflict with collective benefits, causing a tragedy of the commons. In such social dilemmas, the possibility for contributors to invest in a common pool-rewards fund, which will be shared exclusively among contributors, can be powerful for averting the tragedy, as long as the second-order dilemma (i.e. withdrawing contribution to reward funds) can be overcome (e.g. with second-order sanctions). However, the present paper reveals the vulnerability of such pool-rewarding mechanisms to the presence of reward funds raised by defectors and shared among them (i.e. anti-social rewarding), as it causes a cooperation breakdown, even when second-order sanctions are possible. I demonstrate that escaping this social trap requires the additional condition that coalitions of defectors fare poorly compared with pro-socials, with either (i) better rewarding abilities for the latter or (ii) reward funds that are contingent upon the public good produced beforehand, allowing groups of contributors to invest more in reward funds than groups of defectors. These results suggest that the establishment of cooperation through a collective positive incentive mechanism is highly vulnerable to anti-social rewarding and requires additional countermeasures to act in combination with second-order sanctions.
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Peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor involved in diverse biological processes including adipocyte differentiation, glucose homeostasis, and inflammatory responses. Analyses of PPARγ knockout animals have been so far preempted by the early embryonic death of PPARγ-/- embryos as a consequence of the severe alteration of their placental vasculature. Using Sox2Cre/PPARγL2/L2 mice, we obtained fully viable PPARγ-null mice through specific and total epiblastic gene deletion, thereby demonstrating that the placental defect is the unique cause of PPARγ-/- embryonic lethality. The vasculature defects observed in PPARγ-/- placentas at embryonic d 9.5 correlated with an unsettled balance of pro- and antiangiogenic factors as demonstrated by increased levels of proliferin (Prl2c2, PLF) and decreased levels of proliferin-related protein (Prl7d1, PRP), respectively. To analyze the role of PPARγ in the later stage of placental development, when its expression peaks, we treated pregnant wild-type mice with the PPARγ agonist rosiglitazone. This treatment resulted in a disorganization of the placental layers and an altered placental microvasculature, accompanied by the decreased expression of proangiogenic genes such as Prl2c2, vascular endothelial growth factor, and Pecam1. Together our data demonstrate that PPARγ plays a pivotal role in controlling placental vascular proliferation and contributes to its termination in late pregnancy.
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PPARalpha and PPARbeta are expressed in the mouse epidermis during fetal development, but their expression progressively disappears after birth. However, the expression of PPARbeta is reactivated in adult mice upon proliferative stimuli, such as cutaneous injury. We show here that PPARbeta protects keratinocytes from growth factor deprivation, anoikis and TNF-alpha-induced apoptosis, by modulating both early and late apoptotic events via the Akt1 signaling pathway and DNA fragmentation, respectively. The control mechanisms involve direct transcriptional upregulation of ILK, PDK1, and ICAD-L. In accordance with the anti-apoptotic role of PPARbeta observed in vitro, the balance between proliferation and apoptosis is altered in the epidermis of wounded PPARbeta mutant mice, with increased keratinocyte proliferation and apoptosis. In addition, primary keratinocytes deleted for PPARbeta show defects in both cell-matrix and cell-cell contacts, and impaired cell migration. Together, these results suggest that the delayed wound closure observed in PPARbeta mutant mice involves the alteration of several key processes. Finally, comparison of PPARbeta and Akt1 knock-out mice reveals many similarities, and suggests that the ability of PPARbeta to modulate the Akt1 pathway has significant impact during skin wound healing.
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BACKGROUND: The preservation of globe integrity has always been a major concern during the treatment of retinoblastoma for fear of extraocular or metastatic spread. Intravitreal chemotherapy has been attempted as a desperate salvage therapy only for eyes with refractory retinoblastoma. Published data on the safety and efficacy of this route are, however, limited. METHODS: A modified technique of intravitreal injection in eyes with retinoblastoma is described. All children with retinoblastoma who received one or more intravitreal injections using this technique were retrospectively reviewed concerning ocular complications of the injection procedure as well as clinical or histopathological evidence of tumour spread. RESULTS: 30 eyes of 30 children with retinoblastoma received a total of 135 intravitreal injections, with a median follw-up duration of 13.5 months. No extraocular spread was seen on clinical follow-up in any patients and there was no tumour contamination of the retrieved entry sites histopathologically analysed among the five enucleated eyes. No significant ocular side effects were observed except transient localised vitreous haemorrhage (3/135). CONCLUSION: This technique is potentially safe and effective at a low cost and may play a promising role, especially in the treatment of recurrent and/or resistant vitreous disease in retinoblastoma, as an alternative to enucleation and/or external beam radiotherapy. However, this treatment should not replace the primary standard of care of retinoblastoma and should not be considered in group E eyes. Its application should be approved by an ophthalmological-oncological team and it should be performed by an experienced eye surgeon in a tertiary referral centre after careful selection of a tumour-free injection site.
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Passive immunization against β-amyloid (Aβ) has become an increasingly desirable strategy as a therapeutic treatment for Alzheimer's disease (AD). However, traditional passive immunization approaches carry the risk of Fcγ receptor-mediated overactivation of microglial cells, which may contribute to an inappropriate proinflammatory response leading to vasogenic edema and cerebral microhemorrhage. Here, we describe the generation of a humanized anti-Aβ monoclonal antibody of an IgG4 isotype, known as MABT5102A (MABT). An IgG4 subclass was selected to reduce the risk of Fcγ receptor-mediated overactivation of microglia. MABT bound with high affinity to multiple forms of Aβ, protected against Aβ1-42 oligomer-induced cytotoxicity, and increased uptake of neurotoxic Aβ oligomers by microglia. Furthermore, MABT-mediated amyloid plaque removal was demonstrated using in vivo live imaging in hAPP((V717I))/PS1 transgenic mice. When compared with a human IgG1 wild-type subclass, containing the same antigen-binding variable domains and with equal binding to Aβ, MABT showed reduced activation of stress-activated p38MAPK (p38 mitogen-activated protein kinase) in microglia and induced less release of the proinflammatory cytokine TNFα. We propose that a humanized IgG4 anti-Aβ antibody that takes advantage of a unique Aβ binding profile, while also possessing reduced effector function, may provide a safer therapeutic alternative for passive immunotherapy for AD. Data from a phase I clinical trial testing MABT is consistent with this hypothesis, showing no signs of vasogenic edema, even in ApoE4 carriers.