956 resultados para Differential Inclusions with Constraints


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Despite extensive research in the last 150 years, the regional tectonic reconstruction of the Western Alps has remained controversial. The curved orogenic belt consists of several ribbon-like continental terranes (Sesia/Austroalpine, Internal Crystalline Massifs, Brianconnais), which are separated by two or more ophiolitic sutures (Piemonte, Valais, Antrona?, Lanzo/ Canavese?). High-pressure (HP) metamorphism of each terrane occurred during distinct orogenic episodes: at similar to65 Ma in the Sesia/Austroalpine, at similar to45 Ma in the Piemonte zone and at similar to35 Ma in the Internal Crystalline Massifs. It is suggested that these events reflect individual accretionary episodes, which together with kinematic indicators and the speed and direction of plate motions, provide constraints for the discussed reconstruction model. The model involves a prolonged orogenic history that took place during relative convergence of Europe and Adria (here considered as a promontory of the African plate). The first accretionary event involved the Sesia/Austroalpine terrane. Final closure of the Piemonte Ocean occurred during the Eocene (similar to45 Ma) and involved ultra-high-pressure (UHP) metamorphism of the Piemonte oceanic crust. Incorporation of the Brianconnais terrane in the accretionary wedge occurred thereafter, possibly during or after subduction of the Valais Ocean in the late Eocene (45-35 Ma). This subduction was terminated at ca. 35 Ma, when the Internal Crystalline Massifs (i.e. the assumed internal parts of the Brianconnais terrane) were buried into great depths and underwent HP and UHP metamorphism. (C) 2004 Elsevier B.V. All rights reserved.

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In this paper we discuss the existence of solutions for a class of abstract degenerate neutral functional differential equations. Some applications to partial differential equations are considered.

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This work deals with the existence of mild solutions for a class of impulsive functional differential equations of the neutral type associated with the family of linear closed (not necessarily bounded) operators {A(t) : t is an element of 1}. (C) 2009 Elsevier Ltd. All rights reserved.

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In this paper we discuss the existence of alpha-Holder classical solutions for non-autonomous abstract partial neutral functional differential equations. An application is considered.

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Study Design. A case report describing chronic recurrent multifocal osteomyelitis (CRMO) with initial presentation limited to spine, successfully treated by anti-TNF-alpha therapy after failure of conventional treatment methods. Objective. To describe an unusual manifestation and treatment of a rare disease. Summary of Background Data. CRMO is a rare inflammatory bone disease that should be differentiated from bacterial osteomyelitis. Rarely, it can affect the spine and in this case the most important differential diagnosis is infectious spondylodiscitis. The disease has an unpredictable course with exacerbations and spontaneous remissions. Although the majority of cases remit spontaneously (or after the use of nonsteroidal anti-inflammatory drugs [NSAIDs]), some progressive and resistant cases have been reported. Methods. We describe a case of CRMO with an unusual clinical presentation emphasizing the importance of this finding as a differential diagnosis of spondylodiscitis and comment on the available treatment alternatives. Results. A 17-year-old man presented with debilitating dorsal spine pain. Magnetic resonance imaging of the spine revealed bone lesions at multiple vertebral levels. After failure of antibiotic treatment, the diagnosis of CRMO was suggested. An initial good response to NSAIDs was followed by a recurrent course and involvement of peripheral joints besides the use of corticosteroids and other drugs. The introduction of infliximab was followed by complete remission of the disease. Conclusion. Our observation highlights the need of awareness for the differential diagnosis in suspected cases of osteomyelitis not responding to antibiotics. Anti-TNF-alpha agents should be considered in CRMO refractory cases.

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A history of childhood trauma and the presence of dissociative phenomena are considered to be the most important risk factors for psychogenic nonepileptic seizure disorder (PNESD). This case-control study investigated 20 patients with PNESD and 20 with temporal lobe epilepsy (TLE) diagnosed by video/EEG monitoring who were matched for gender and age. Patients with both conditions were not included in the study. Groups were evaluated for age at onset and at diagnosis, worst lifetime weekly seizure frequency, trauma history, and presence of dissociative phenomena. Age at onset (P = 0.007) and age at diagnosis (P < 0.001) were significantly higher in the PNESD group than the control group, as were the scores on the Dissociative Experiences Scale (P < 0.001) and Childhood Trauma Questionnaire (P = 0.014). Only the differences in scores on the Childhood Trauma Questionnaire subscales Emotional Neglect (P = 0.013) and Emotional Abuse (P = 0.014) reached statistical significance. Dissociative phenomena and a reported history of childhood trauma are more common in patients with PNESD than in those with TLE. However, only emotional neglect and abuse were associated with PNESD in this study. (C) 2010 Elsevier Inc. All rights reserved.

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To evaluate differential gene expression in penile tissue after treatment with the phosphodiesterase 5 (PDE5) inhibitor tadalafil, as of the three clinically available PDE5 inhibitors (sildenafil, tadalafil, and vardenafil) used for the treatment of erectile dysfunction (ED), tadalafil has a long half-life and low incidence of side-effects. In all, 32 adult rats were divided into two groups. The control group received 0.5 mL of drinking water alone, while the tadalafil group was treated with tadalafil at a dose of 0.27 mg/kg. At 4 h after treatment with water or tadalafil the rats were killed and the penile tissue was removed. The total RNA was isolated from the penile tissue from both groups and differentially expressed genes were identified by cDNA microarray analysis. To validate the expression data from the microarray analysis, quantitative real-time polymerase chain reaction (PCR) and immunohistochemistry were used. In all, 153 genes were differentially expressed between the control group and the tadalafil group. We validated the microarray results by quantitative PCR for the insulin-like growth factor binding protein 6 (IGFBP-6) gene and the neuronal calcium sensor 1 (NCS-1) gene, both of which were up-regulated in the tadalafil group, and for the natriuretic peptide receptor 1 (NPR-1) gene that was down-regulated in this group. Immunohistochemistry showed localization of the NCS-1 protein in sinusoid trabeculae of the corpus cavernosum in control and tadalafil-treated rats. There was differential expression in 153 genes after tadalafil treatment. Some of these genes such as IGFBP-6, NPR-1 and NCS-1, might result in new targets in the treatment of ED.

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Objectives: To evaluate p63 expression in laryngeal squamous cell carcinoma and its prognostic significance. Methods: p63 expression was examined by immunohistochemistry and scored in 127 patients with laryngeal squamous cell carcinomas. Results: Sixty-two cases had scored 3, sixty had scored 2, four had scored 1 and one case did not show any expression (48.8, 47.2, 3.1 and 0.8%, respectively). Overall survival was 73.9% at 24 months and 59.5% at 60 months. The disease-free survival was 77.2 and 75.1%, and the disease-specific survival was 79 and 67% at 24 and 60 months, respectively. Uni- and multivariate analysis identified that decreased immunoexpression of protein p63 was a statistically significant factor for the risk of recurrence and death by cancer. Conclusions: p63 expression was highly prevalent in laryngeal squamous cell carcinomas, and its underexpression was correlated with a worse prognosis. Copyright (C) 2010 S. Karger AG, Basel

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Background. Chagas disease is caused by the protozoan parasite Trypanosoma cruzi. Among T. cruzi-infected individuals, only a subgroup develops severe chronic Chagas cardiomyopathy (CCC); the majority remain asymptomatic. T. cruzi displays numerous ligands for the Toll-like receptors (TLRs), which are an important component of innate immunity that lead to the transcription of proinflammatory cytokines by nuclear factor-kappa B. Because proinflammatory cytokines play an important role in CCC, we hypothesized that single-nucleotide polymorphisms (SNPs) in the genes that encode proteins in the TLR pathway could explain differential susceptibility to CCC among T. cruzi-infected individuals. Methods. For 169 patients with CCC and 76 T. cruzi-infected, asymptomatic individuals, we analyzed SNPs by use of polymerase chain reaction-restriction fragment length polymorphism analysis for the genes TLR1, TLR2, TLR4, TLR5, TLR9, and MAL/TIRAP, which encodes an adaptor protein. Results. Heterozygous carriers of the MAL/TIRAP variant S180L were more prevalent in the asymptomatic group (24 [32%] of 76 subjects) than in the CCC group (21 [12%] of 169) (chi(2) = 12.6; P = .0004 [adjusted P (P(c)) = .0084]; odds ratio [OR], 0.31 [95% confidence interval {CI}, 0.16-0.60]). Subgroup analysis showed a stronger association when asymptomatic patients were compared with patients who had severe CCC (i.e., patients with left-ventricular ejection fraction <= 40%) (chi(2) = 11.3; P = .0008 [P(c) = .017]; OR, 0.22 [95% CI, 0.09-0.56]) than when asymptomatic patients were compared with patients who had mild CCC (i.e., patients with left-ventricular ejection fraction >40%) (chi(2) = 7.7; P = .005 [P(c) = .11]; OR, 0.33 [95% CI, 0.15-0.73]). Conclusion. T. cruzi-infected individuals who are heterozygous for the MAL/TIRAP S180L variant that leads to a decrease in signal transduction upon ligation of TLR2 or TLR4 to their respective ligand may have a lower risk of developing CCC.

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A robust semi-implicit central partial difference algorithm for the numerical solution of coupled stochastic parabolic partial differential equations (PDEs) is described. This can be used for calculating correlation functions of systems of interacting stochastic fields. Such field equations can arise in the description of Hamiltonian and open systems in the physics of nonlinear processes, and may include multiplicative noise sources. The algorithm can be used for studying the properties of nonlinear quantum or classical field theories. The general approach is outlined and applied to a specific example, namely the quantum statistical fluctuations of ultra-short optical pulses in chi((2)) parametric waveguides. This example uses a non-diagonal coherent state representation, and correctly predicts the sub-shot noise level spectral fluctuations observed in homodyne detection measurements. It is expected that the methods used wilt be applicable for higher-order correlation functions and other physical problems as well. A stochastic differencing technique for reducing sampling errors is also introduced. This involves solving nonlinear stochastic parabolic PDEs in combination with a reference process, which uses the Wigner representation in the example presented here. A computer implementation on MIMD parallel architectures is discussed. (C) 1997 Academic Press.

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Epithelial to mesenchymal transition (EMT) is a process implicated in cancer progression in which the underlying cellular changes have been identified mainly using in vitro models. We determined the expression of some putative EMT biomarkers including E-cadherin, beta-catenin, zinc finger factor Snail (Snail), transforming growth factor beta 1 (TGF beta 1), TGF beta type II receptor (TBRII) and the HGF receptor (c-met) and their possible correlation to progression and overall survival in a series of breast ductal carcinoma in situ (DCIS) and invasive ductal carcinomas (IDC). Biomarkers were immunohistochemically determined in 55 IDC specimens from which 21 had lymph node metastases and in 95 DCIS specimens, 46 of these cases associated to invasive carcinoma, in a tissue microarray (TMA). Positive cytoplasmic staining of TGF beta 1 (78.2%), c-met (43.6%), Snail (34.5%), TBRII (100%), membranous E-cadherin (74.5%) and membranous/cytoplasmic beta-catenin (71%) were detected in the IDC samples. Metastatic lymph node samples displayed similar frequencies. A significant increase of c-met and TGF beta 1 positivity along DCIS to IDC progression was noted but only TGF beta 1 positivity was associated with presence of lymph node metastases and advanced stages in IDC. The evaluation of the other EMT markers in DCIS did not show differences in positivity rate as compared to invasive carcinomas. DCIS either pure or associated to IDC showed similar expression of the analyzed biomarkers. All the carcinomas exhibited positive expression of TBRII. Associations between the markers, determined by Spearman`s correlation coefficient, showed a significant association between TGF beta 1 and respectively E-cadherin, beta-catenin and cmet in DCIS cases, but in invasive carcinomas only cadherin and catenin were positively correlated. Kaplan-Meier survival curves revealed that none of the EMT biomarkers analyzed were correlated with survival, which was significantly determined only by clinical and hormone receptor parameters.

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Objectives: To examine the effects of triiodothyronine (T(3)), 17 beta-estradiol (E(2)), and tamoxifen (TAM) on transforming growth factor (TGF)-alpha gene expression in primary breast cancer cell cultures and interactions between the different treatments. Methods and results: Patients included in the study (no.=12) had been newly diagnosed with breast cancer. Fresh human breast carcinoma tissue was cut into 0.3-mm slices. These slices were placed in six 35-mm dishes on 2-ml organ culture medium. Dishes received the following treatments: dish 1: ethanol; dish 2: T(3); dish 3: T(3)+TAM; dish 4: TAM; dish 5: E(2); dish 6: E(2)+TAM. TGF-alpha mRNA content was normalized to glyceraldehyde-3-phosphate dehydrogenase mRNA levels. All tissues included in this study were positive for estrogen receptor (ER) and thyroid hormone receptor expression. Treatment with T(3) for 48 h significantly increased TGF-alpha mRNA levels compared to controls (15-fold), and concomitant treatment with TAM reduced expression to 3.4-fold compared to controls. When only TAM was added to the culture medium, TGF-alpha mRNA expression increased 5.3-fold, significantly higher than with all other treatment modalities. Conclusion: We demonstrate that TGF-alpha mRNA expression is more efficiently upregulated by T(3) than E(2). Concomitant treatment with TAM had a mitigating effect on the T(3) effect, while E(2) induced TGF-alpha upregulation. Our findings show some similarities between primary culture and breast cancer cell lines, but also some important differences: a) induction of TGF-alpha, a mitogenic protein, by TAM; b) a differential effect of TAM that may depend on relative expression of ER alpha and beta; and c) supraphysiological doses of T3 may induce mitogenic signals in breast cancer tissue under conditions of low circulating E(2).. Endocrinol. Invest. 31: 1047-1051, 2008) (c) 2008, Editrice Kurtis

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The technique of polymerase chain reaction (PCR) differential display was used to detect alterations in gene expression after chronic alcohol administration. Male Wistar rats were treated with ethanol vapor for 14 days. The cDNA generated from mRNA isolated from the hippocampi of ethanol-treated and control animals was compared by PCR differential display. A differentially expressed cDNA fragment was used to screen mRNA samples by Northern analysis. The level of a mRNA was significantly elevated (x 2.5) in the hippocampus, but not the cortex of alcohol-treated rats up to 48 hr after withdrawal. Sequence analysis of the cDNA fragment revealed an almost perfect homology to rat mitochondrial NADH dehydrogenase subunit 4 mRNA. The selective induction of this mRNA in alcohol-treated rat brain areas suggests altered metabolic processes and possible dysfunction of the mitochondria. The technique of PCR differential display may prove useful in further analysis of gene expression during alcohol dependence and withdrawal.

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Conotoxins are small, cysteine-rich peptides isolated from the venom of Conus spp. of predatory marine snails, which selectively target specific receptors and ion channels critical to the functioning of the neuromuscular system. alpha-Conotoxins PnIA and PnIB are both 16-residue peptides (differing in sequence at only two positions) isolated from the molluscivorous snail Conus pennaceus. In contrast to the muscle-selective alpha-conotoxin GI from Conus geographus, PnIA and PnIB block the neuronal nicotinic acetylcholine receptor (nAChR). Here, we describe the crystal structure of PnIB, solved at a resolution of 1.1 Angstrom and phased using the Shake-and-Bake direct methods program. PnIB crystals are orthorhombic and belong to the space group P2(1)2(1)2(1) with the following unit cell dimensions: a = 14.6 Angstrom, b = 26.1 Angstrom, and c = 29.2 Angstrom. The final refined structure of alpha-conotoxin PnIB includes all 16 residues plus 23 solvent molecules and has an overall R-factor of 14.7% (R-free of 15.9%). The crystal structures of the alpha-conotoxins PnIB and PnIA are solved from different crystal forms, with different solvent contents. Comparison of the structures reveals them to be very similar, showing that the unique backbone and disulfide architecture is not strongly influenced by crystal lattice constraints or solvent interactions. This finding supports the notion that this structural scaffold is a rigid support for the presentation of important functional groups. The structures of PnIB and PnIA differ in their shape and surface charge distribution from that of GI.

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Maximization of bone accrual during the growing years is thought to be an important factor in minimizing fracture risk in old age. Mechanical loading through physical activity has been recommended as a modality for the conservation of bone mineral in adults; however, few studies have evaluated the impact of different loading regimes in growing children. The purpose of this study was to compare bone mineral density (BMD) in weight-bearing and non-weight-bearing limbs in 17 children with unilateral Legg Calve Perthes Disease (LCPD). Children with this condition have an altered weight-bearing pattern whereby there is increased mechanical loading on the noninvolved normal hip and reduced loading on the involved painful hip. Thus, these children provide a unique opportunity to study the impact of differential mechanical loading on BMD during the growing years while controlling for genetic disposition. BMD at four regions of the proximal femur (trochanter, intertrochanter, femoral neck, total of the regions) was measured using dual energy x-ray absorptiometry (DXA), and the values were compared between the involved and noninvolved sides of the children with LCPD. The BMD of both sides also were compared with normative values based on both chronological and skeletal age data. A significantly higher BMD was found on the noninvolved side over the involved side for all regions (P