926 resultados para Gellan-gum hydrogels and spongy-like


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BACKGROUND: Knowledge about their past medical history is central for childhood cancer survivors to ensure informed decisions in their health management. Knowledge about information provision and information needs in this population is still scarce. We thus aimed to assess: (1) the information survivors reported to have received on disease, treatment, follow-up, and late effects; (2) their information needs in these four domains and the format in which they would like it provided; (3) the association with psychological distress and quality of life (QoL). PROCEDURE: As part of the Follow-up survey of the Swiss Childhood Cancer Survivor Study, we sent a questionnaire to all survivors (≥18 years) who previously participated to the baseline survey, were diagnosed with cancer after 1990 at an age of <16 years. RESULTS: Most survivors had received oral information only (on illness: oral: 82%, written: 38%, treatment: oral: 79%, written: 36%; follow-up: oral: 77%, written: 23%; late effects: oral: 68%, written: 14%). Most survivors who had not previously received any information rated it as important, especially information on late effects (71%). A large proportion of survivors reported current information needs and would like to receive personalized information especially on late effects (44%). Survivors with higher information needs reported higher psychological distress and lower QoL. CONCLUSIONS: Survivors want to be more informed especially on possible late effects, and want to receive personalized information. Improving information provision, both qualitatively and quantitatively, will allow survivors to have better control of their health and to become better decision makers.

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We study the effects of globalization on risk sharing and welfare. Like previous literature, weassume that countries cannot commit to repay their debts. Unlike previous literature, we assumethat countries cannot discriminate between domestic and foreign creditors when repaying theirdebts. This creates novel interactions between domestic and international trade in assets. (i)Increases in domestic trade raise the bene.ts of enforcement and facilitate international trade.In fact, in our setup countries can obtain international risk sharing even in the absence of defaultpenalties. (ii) Increases in foreign trade .i.e. globalization.raise the costs of enforcement andhamper domestic trade. As a result, globalization may worsen domestic risk sharing and lowerwelfare. We show how these e¤ects depend on various characteristics of tradable goods andexplore the roles of borrowing limits, debt renegotiations, and trade policy.

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Numerous preclinical and clinical studies have shown that interleukin-2 (IL-2) induces regression of metastatic tumors. We have conducted a phase I/II, multicenter, open-label, dose-escalating study to evaluate the safety, efficacy, and biological effects of repeated intratumoral injections of adenovirus-IL-2 (TG1024) in patients with advanced solid tumors and melanoma. Thirty five patients (twenty-five with metastatic melanoma and ten with other solid tumors) were treated in eight successive cohorts at dose levels ranging from 3 x 10(8) to 3 x 10(11) viral particles (vp). Intratumoral TG1024 injections in combination with dacarbazine (DTIC) were tested in metastatic melanoma in one cohort. No clinical responses were observed at doses below 3 x 10(11) vp. Six local objective responses were recorded in patients receiving 3 x 10(11) vp per treatment [five in metastatic melanoma and one in metastatic squamous cell carcinoma (SCC) of the skin], of which two were complete responses (CRs). Most of the common side effects were injection site reactions and flu-like syndrome. TG1024 dose intensification across cohorts resulted in increased serum IL-2 levels after the injection. Intratumoral TG1024 injection induced pronounced inflammation of the treated lesion, with predominant CD8(+), TIA+ lymphocytic infiltrate. Our results show that intratumoral injections of TG1024 are safe and well tolerated. The clinical activity of TG1024 observed in this study warrants further investigations.

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Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is known as a "death ligand"-a member of the TNF superfamily that binds to receptors bearing death domains. As well as causing apoptosis of certain types of tumor cells, TRAIL can activate both NF-kappaB and JNK signalling pathways. To determine the role of TGF-beta-Activated Kinase-1 (TAK1) in TRAIL signalling, we analyzed the effects of adding TRAIL to mouse embryonic fibroblasts (MEFs) derived from TAK1 conditional knockout mice. TAK1-/- MEFs were significantly more sensitive to killing by TRAIL than wild-type MEFs, and failed to activate NF-kappaB or JNK. Overexpression of IKK2-EE, a constitutive activator of NF-kappaB, protected TAK1-/- MEFs against TRAIL killing, suggesting that TAK1 activation of NF-kappaB is critical for the viability of cells treated with TRAIL. Consistent with this model, TRAIL failed to induce the survival genes cIAP2 and cFlipL in the absence of TAK1, whereas activation of NF-kappaB by IKK2-EE restored the levels of both proteins. Moreover, ectopic expression of cFlipL, but not cIAP2, in TAK1-/- MEFs strongly inhibited TRAIL-induced cell death. These results indicate that cells that survive TRAIL treatment may do so by activation of a TAK1-NF-kappaB pathway that drives expression of cFlipL, and suggest that TAK1 may be a good target for overcoming TRAIL resistance.

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BACKGROUND: Along the chromosome of the obligate intracellular bacteria Protochlamydia amoebophila UWE25, we recently described a genomic island Pam100G. It contains a tra unit likely involved in conjugative DNA transfer and lgrE, a 5.6-kb gene similar to five others of P. amoebophila: lgrA to lgrD, lgrF. We describe here the structure, regulation and evolution of these proteins termed LGRs since encoded by "Large G+C-Rich" genes. RESULTS: No homologs to the whole protein sequence of LGRs were found in other organisms. Phylogenetic analyses suggest that serial duplications producing the six LGRs occurred relatively recently and nucleotide usage analyses show that lgrB, lgrE and lgrF were relocated on the chromosome. The C-terminal part of LGRs is homologous to Leucine-Rich Repeats domains (LRRs). Defined by a cumulative alignment score, the 5 to 18 concatenated octacosapeptidic (28-meric) LRRs of LGRs present all a predicted alpha-helix conformation. Their closest homologs are the 28-residue RI-like LRRs of mammalian NODs and the 24-meres of some Ralstonia and Legionella proteins. Interestingly, lgrE, which is present on Pam100G like the tra operon, exhibits Pfam domains related to DNA metabolism. CONCLUSION: Comparison of the LRRs, enable us to propose a parsimonious evolutionary scenario of these domains driven by adjacent concatenations of LRRs. Our model established on bacterial LRRs can be challenged in eucaryotic proteins carrying less conserved LRRs, such as NOD proteins and Toll-like receptors.

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RATIONALE: Dopamine D2 receptors are the main target of antipsychotic drugs. In the brain, D2 receptors coexpress with adenosine A2A and CB1 cannabinoid receptors, leading to functional interactions. OBJECTIVES: The protein and messenger RNA (mRNA) contents of A2A, D2, and CB1 receptors were quantified in postmortem prefrontal cortex of subjects with schizophrenia. MATERIALS AND METHODS: The study was performed in subjects suffering schizophrenia (n=31) who mainly died by suicide, matched with non-schizophrenia suicide victims (n=13) and non-suicide controls (n=33). The density of receptor proteins was evaluated by immunodetection techniques, and their relative mRNA expression was quantified by quantitative real-time polymerase chain reaction. RESULTS: In schizophrenia, the densities of A2A (90+/-6%, n=24) and D2-like receptors (95+/-5%, n=22) did not differ from those in controls (100%). Antipsychotic treatment did not induce changes in the protein expression. In contrast, the immunodensity of CB1 receptors was significantly decreased (71+/-7%, n=11; p<0.05) in antipsychotic-treated subjects with schizophrenia but not in drug-free subjects (104+/-13%, n=11). The relative mRNA amounts encoding for A2A, D2, and CB1 receptors were similar in brains of drug-free, antipsychotic-treated subjects with schizophrenia and controls. CONCLUSIONS: The findings suggest that antipsychotics induce down-regulation of CB1 receptors in brain. Since A2A, D2, and CB1 receptors coexpress on brain GABAergic neurons and reductions in markers of GABA neurotransmission have been identified in schizophrenia, a lower density of CB1 receptor induced by antipsychotics could represent an adaptative mechanism that reduces the endocannabinoid-mediated suppression of GABA release, contributing to the normalization of cognitive functions in the disorder.

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I. Résumé large publicIRF6 est un médiateur de Notch dans la différenciation des kératinocytes et dans sa fonction de suppresseur de tumeursLa peau est l'organe le plus important du corps humain, elle représente chez l'adulte une surface d'environ 1,5 m2 et elle est composée de 2000 milliards de cellules. La peau est composée de plusieurs types cellulaires dont les kératinocvtes. Ces cellules, qui se trouvent dans la couche la plus externe de la peau (Pépiderme), nous protègent de la déshydratation et des agressions externes telles que les infections et rayons ultraviolets. Cette fonction de « barrière » est mise en place grâce à un processus appelé différenciation des kératinocvtes durant lequel les kératinocytes deviennent matures et finalement meurent pour former la couche cornée la plus externe difficilement pénétrable. L'homéostasie tissulaire est un mécanisme qui régule l'équilibre entre prolifération, différentiation et mort cellulaire. Une perturbation de cet équilibre peut mener à la formation d'une tumeur. Il existe différents types de tumeurs de la peau. Nous nous sommes intéressés aux «carcinomes spino-cellulaires» (SCC) qui se développent à partir des keratinocytes en différenciation. Notch est une molécule impliquée positivement dans la différenciation des kératinocytes et joue un rôle prépondérant dans la suppression des tumeurs kératinocytaires comme les SCC dans lesquelles Notch est faiblement exprimé. L'implication de Notch dans la différenciation et dans la carcinogenèse kératinocytaire n'est plus controversée, mais les mécanismes qui sont à la base de ces fonctions restent encore à élucider. IRfF6 est une protéine qui, d'après sa structure, a été classée parmi une famille de régulateurs de la défense de l'organisme (IRFs). Des études ultérieures ont montré qu'IRf 6 n'a pas de rôle dans la réponse immunitaire mais qu'il est plutôt impliqué dans le développement de l'épiderme. Dans ce travail, nous avons établi que, dans les kératinocytes, l'expression d'IPJF6 est contrôlé par Notch et que, comme pour ce dernier, elle est réduite dans les SCCs. De plus, nous avons observé qu'IRF6 régule les mêmes gènes que Notch, et qu'il est en effet un médiateur de la fonction de Notch dans la différenciation des kératinocytes. Parmi les gènes contrôlés par l'axe Notch-IRF6 il y en a trois qui sont sur-exprimés dans les SCCs et qui sont réprimés par cet axe. Il s'agit d'une part d'IRF3 et IRF7, deux autres membres de la famille IRF, et du récepteur EGFR (Epidermal growth factor receptor), un oncogène (un gène impliqué dans l'accélération de la formation de tumeurs). Dans leur ensemble, ces découvertes nous informent sur les mécanismes impliqués dans les fonctions pro-differentiatrice et tumeur suppressive de Notch. Plus encore, elles ouvrent des perspectives intéressantes quant au développement de nouvelles approches thérapeutiques dans le traitement des cancers.II. RésuméLa voie de signalisation de Notch joue un rôle très important dans la différenciation cellulaire et dans la carcinogenèse de nombreux tissus. Dans les kératinocytes, elle agit comme suppresseur de tumeurs, fonction altérée dans les cancers spino cellulaires SCC (tumeurs kératinocytaires) de part la perte d'expression de Notch.Bien que les fonctions pro-différenciatrice et tumeur-suppressive de la voie de signalisation de Notch soient aujourd'hui reconnues, les mécanismes sous-jacents restent à explorer.Dans ce travail, nous montrons qu'IRF6, un membre de la famille des régulateurs de la voie de l'interféron (IRF), ne possédant pas de rôles dans la réponse immunitaire mais essentiel dans le développement de l'épiderme, est d'autant plus exprimé que le kératinocytes sont différenciées alors que son expression est drastiquement diminuée dans les SCC. De façon intéressante, l'expression d'IRF6 durant la différenciation kératinocytaire est directement contrôlée par Notch.Dans les kératinocytes l'expression accrue d'IRP6 a les mêmes effets que 1'activation de la voie de Notch induisant les marqueurs de différentiation des couches supra-basales de l'épiderme et inhibant ceux de la couche basale impliqués dans la prolifération cellulaire. Cependant IRF6 n'est pas impliqué dans la régulation d'autres cibles de Notch, comme p21WAFI/CiP' et Hesl. Comme Notch, IRF6 contrôle négativement l'expression de EGFR et IRF3/7. De ce fait EGFR et IRF3 et IRF7 sont fortement exprimés dans les SCCs humaines où l'expression de Notch et IRF6 est fortement réduite.En conclusion, nous avons démontré qu'IRF6 est une cible directe de Notch/CSL dans les keratinocytes qui medie les effets "non-canonique" de cette voie de signalisation dans la différentiation et dans la suppression tumorale.III. SummaryThe Notch pathway is an important regulator of differentiation and carcinogenesis. In keratinocytes it acts as tumour suppressor and the Notch gene is markedly reduced in keratinocyte-derived squamous cell carcinoma (SCC). While the pro-differentiation and tumour suppressive functions of Notch signalling in keratinocytes are well established, the underlying mechanisms are still poorly understood, We report here that Interferon Regulatory Factor 6 (IRF6), an IRF family member with an essential role in epidermal development, is downmodulated in SCC and is induced in differentiating cells. We observed that the induction of IRF6 in differentiating keratinocytes is suppressed by Notch inhibition. IRF6 expression is also decreased in mice with keratinocyte-specific deletion of the Notch 1/2.Moreover we show that the expression of this gene is induced by Notch activation through a CSL-dependent mechanism even under conditions of protein synthesis inhibition, with endogenous Notch 1 binding to the IRF6 promoter.Increased IRJF6 expression is necessary for the impact of Notch activation on differentiation markers K1 and Involucrin, and proliferation markers integrins and p63, but not on other "canonical" Notch targets like p21WAF1/Cipl, Hes1 and Hey1. Like Notch 1, IRF6 down-modulates expression of epidermal growth factor receptor (EGFR) as well as two other IRF family members, IRF3 and 7, which we previously linked to positive control of p63 expression. Expression of IRF3, IRF7 and EGFR is enhanced in cutaneous squamous cell carcinomas, illustrating a strikingly opposite pattern compared to Notch and IRF6.Thus, IRF6 is a primary Notch target in keratinocytes, which mediates the effects of this pathway on differentiation and contributes to tumor suppression.

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PURPOSE: The phosphoinositide 3-kinase (PI3K)/Akt pathway is frequently activated in human cancer and plays a crucial role in medulloblastoma biology. We were interested in gaining further insight into the potential of targeting PI3K/Akt signaling as a novel antiproliferative approach in medulloblastoma. EXPERIMENTAL DESIGN: The expression pattern and functions of class I(A) PI3K isoforms were investigated in medulloblastoma tumour samples and cell lines. Effects on cell survival and downstream signaling were analyzed following down-regulation of p110alpha, p110beta, or p110delta by means of RNA interference or inhibition with isoform-specific PI3K inhibitors. RESULTS: Overexpression of the catalytic p110alpha isoform was detected in a panel of primary medulloblastoma samples and cell lines compared with normal brain tissue. Down-regulation of p110alpha expression by RNA interference impaired the growth of medulloblastoma cells, induced apoptosis, and led to decreased migratory capacity of the cells. This effect was selective, because RNA interference targeting of p110beta or p110delta did not result in a comparable impairment of DAOY cell survival. Isoform-specific p110alpha inhibitors also impaired medulloblastoma cell proliferation and sensitized the cells to chemotherapy. Medulloblastoma cells treated with p110alpha inhibitors further displayed reduced activation of Akt and the ribosomal protein S6 kinase in response to stimulation with hepatocyte growth factor and insulin-like growth factor-I. CONCLUSIONS: Together, our data reveal a novel function of p110alpha in medulloblastoma growth and survival.

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FLICE-inhibitory protein, FLIP (Casper/I-FLICE/FLAME-1/CASH/CLARP/MRIT), which contains two death effector domains and an inactive caspase domain, binds to FADD and caspase-8, and thereby inhibits death receptor-mediated apoptosis. Here, we characterize the inhibitory effect of FLIP on a variety of apoptotic pathways. Human Jurkat T cells undergoing Fas ligand-mediated apoptosis in response to CD3 activation were completely resistant when transfected with FLIP. In contrast, the presence of FLIP did not affect apoptosis induced by granzyme B in combination with adenovirus or perforin. Moreover, the Fas ligand, but not the perforin/granzyme B-dependent lytic pathway of CTL, was inhibited by FLIP. Apoptosis mediated by chemotherapeutic drugs (i.e., doxorubicin, etoposide, and vincristine) and gamma irradiation was not affected by FLIP or the absence of Fas, indicating that these treatments can induce cell death in a Fas-independent and FLIP-insensitive manner.

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Interactions between Notch1 receptors on lymphoid progenitors and Delta-like 4 (DL4) ligands on cortical thymic epithelial cells (cTEC) are essential for T cell lineage commitment, expansion, and maturation in the thymus. Using a novel mAb against DL4, we show that DL4 levels on cTEC are very high in the fetal and neonatal thymus when thymocyte expansion is maximal but decrease dramatically in the adult when steady-state homeostasis is attained. Analysis of mutant mouse strains where thymocyte development is blocked at different stages indicates that lymphostromal interactions ("thymus crosstalk") are required for DL4 down-regulation on cTEC. Reconstitution of thymocyte development in these mutant mice further suggests that maturation of thymocytes to the CD4(+)CD8(+) stage and concomitant expansion are needed to promote DL4 down-regulation on cTEC. Collectively, our data support a model where thymic crosstalk quantitatively regulates the rate of Notch1-dependent thymopoiesis by controlling DL4 expression levels on cTEC.

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Lymphocyte homeostasis is a balance between lymphocyte proliferation and lymphocyte death. Tight control of apoptosis is essential for immune function, because its altered regulation can result in cancer and autoimmunity. Signals from members of the tumour-necrosis-factor receptor (TNF-R) family, such as Fas and TNF-R1, activate the caspase cascade and result in lymphocyte death by apoptosis. Anti-apoptotic proteins, such as FLIP (also known as FLICE/caspase-8 inhibitory protein) have recently been identified. FLIP expression is tightly regulated in T cells and might be involved in the control of both T-cell activation and death. Abnormal expression of FLIP might have a role not only in autoimmune diseases, but also in tumour development and cardiovascular disorders.

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The filamentous brain lesions that define Alzheimer disease (AD) consist of senile plaques and neurofibrillary tangles. Undulated pathological filaments--curly fibers or neuropil threads--also occur in the neuropil. Beta-amyloid precursor proteins are synthesized by many cells outside the central nervous system and recently, deposition of beta-amyloid-protein was reported to occur in non-neuronal tissues. In addition, increasing data claim the importance of chronic inflammation in the pathogenesis of AD. These observations suggest that AD may be a widespread systemic disorder. Here we report that pathological argyrophilic filaments with histochemical properties of amyloid showing striking morphological similarity to curly fibers and/or tangles accumulate not only in ependymal layer and in epithelial cells of choroid plexus, but also in several other organs (e.g. liver, pancreas, ovary, testis, thyroid) in AD. The ependyma, choroid plexus, and various organs of 39 autopsy cases were analyzed. In search of curly fiber and tangle-like changes in organs other than brain, 395 blocks from 21 different tissues of 24 AD cases, 5 cases with discrete or moderate AD-type changes, and 10 control cases were investigated. We found in non-neuronal cells "curly fibers" or "tangles" immunoreactive with antibodies to P component, Tau-protein, ubiquitin, fibronectin, and Apolipoprotein-E, but lacking immunoreactivity with antibodies to neurofilament proteins. Ultrastructurally they consist of densely packed straight and paired helical filaments and closely resemble neurofibrillary tangles and neuropil threads. These observations indicate that the formation of "curly fibers" and "tangles" is not unique to the central nervous system. The results suggest that AD might be a systemic disorder or that similar fibrillary changes to tangles and curly fibers may also be associated with other amyloidosis than beta-amyloidosis. Further investigations are necessary to understand the pathogenetic interest of these fibrillary changes outside the CNS.

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The T-cell derived cytokine CD40 ligand is overexpressed in patients with autoimmune diseases. Through activation of its receptor, CD40 ligand leads to a tumor necrosis factor (TNF) receptor 1 (TNFR1) dependent impairment of locomotor activity in mice. Here we report that this effect is explained through a promotion of sleep, which was specific to non-rapid eye movement (NREM) sleep while REM sleep was suppressed. The increase in NREM sleep was accompanied by a decrease in EEG delta power during NREM sleep and by a decrease in the expression of transcripts in the cerebral cortex known to be associated with homeostatic sleep drive, such as Homer1a, Early growth response 2, Neuronal pentraxin 2, and Fos-like antigen 2. The effect of CD40 activation was mimicked by peripheral TNF injection and prevented by the TNF blocker etanercept. Our study indicates that sleep-wake dysregulation in autoimmune diseases may result from CD40 induced TNF:TNFR1 mediated alterations of molecular pathways, which regulate sleep-wake behavior.

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Kudzu is a cover crop that has escaped cultivation in some subtropical and warm temperate regions. Kudzu has previously demonstrated broad intraspecific physiological plasticity while colonizing new environments. The objective of this paper was to investigate characteristics of kudzu leaflet anatomy that might contribute to its successful growth in climatically distinct environments, and to escape cultivation as well. Fresh and fixed leaflet strips of field-grown plants were analyzed. The lower epidermis of kudzu showed a higher frequency of stomata (147 ± 19 stomata mm-2) than the upper epidermis (26 ± 17 stomata mm-2). The average number of trichomes per square milimeter was 8 for both the upper and the lower epidermis. The average trichome length was 410 ± 200 mum for the upper epidermis and 460 ± 190 mum for the lower epidermis. Cuticle thickness was not considerably different between lower and upper epidermis. The leaflet blade consisted basically of two layers (upper and lower) of unicellular epidermis, two layers of palisade parenchyma and one layer of spongy parenchyma. One layer of paraveinal mesophyll was found between palisade and spongy parenchyma. In conclusion, leaflets of kudzu present anatomical characteristics that might contribute to the broad physiological plasticity shown by kudzu.

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Intensive research is devoted to unravel the neurobiological mechanisms mediating adult hippocampal neurogenesis, its regulation by antidepressants, and its behavioral consequences. Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine that is expressed in the CNS, where its function is unknown. Here, we show, for the first time, the relevance of MIF expression for adult hippocampal neurogenesis. We identify MIF expression in neurogenic cells (in stem cells, cells undergoing proliferation, and in newly proliferated cells undergoing maturation) in the subgranular zone of the rodent dentate gyrus. A causal function for MIF in cell proliferation was shown using genetic (MIF gene deletion) and pharmacological (treatment with the MIF antagonist Iso-1) approaches. Behaviorally, genetic deletion of MIF resulted in increased anxiety- and depression-like behaviors, as well as of impaired hippocampus-dependent memory. Together, our studies provide evidence supporting a pivotal function for MIF in both basal and antidepressant-stimulated adult hippocampal cell proliferation. Moreover, loss of MIF results in a behavioral phenotype that, to a large extent, corresponds with alterations predicted to arise from reduced hippocampal neurogenesis. These findings underscore MIF as a potentially relevant molecular target for the development of treatments linked to deficits in neurogenesis, as well as to problems related to anxiety, depression, and cognition.