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941.
We propose specification tests for the variance of a diffusion that do not require complete knowledge of the functional form under the null. We first propose a test for the constancy of the variance that, under the null of constancy, has a limiting normal distribution, while under the alternative of either unconditional or conditional heteroskedasticity it diverges at an appropriate rate. We then propose a test for the null of a parametric specification against the alternative of a more general functional form. Under the null, the test has a well-defined limiting distribution, normal in the unconditional and mixed normal in the conditional heteroskedasticity case; under the alternative, it diverges. 相似文献
942.
943.
Laura Caliogna Viviana Guerrieri Salvatore Annunziata Valentina Bina Alice Maria Brancato Alberto Castelli Eugenio Jannelli Alessandro Ivone Federico Alberto Grassi Mario Mosconi Gianluigi Pasta 《International journal of molecular sciences》2021,22(18)
Ehlers-Danlos syndromes (EDS) are an inherited heterogeneous group of connective tissue disorders characterized by an abnormal collagen synthesis affecting skin, ligaments, joints, blood vessels, and other organs. It is one of the oldest known causes of bruising and bleeding, and it was described first by Hippocrates in 400 BC. In the last years, multiple gene variants involved in the pathogenesis of specific EDS subtypes have been identified; moreover, new clinical diagnostic criteria have been established. New classification models have also been studied in order to differentiate overlapping conditions. Moreover, EDS shares many characteristics with other similar disorders. Although distinguishing between these seemingly identical conditions is difficult, it is essential in ensuring proper patient care. Currently, there are many genetic and molecular studies underway to clarify the etiology of some variants of EDS. However, the genetic basis of the hypermobile type of EDS (hEDS) is still unknown. In this review, we focused on the study of two of the most common forms of EDS—classic and hypermobile—by trying to identify possible biomarkers that could be of great help to confirm patients’ diagnosis and their follow up. 相似文献
944.
Valentina Croci 《Architectural Design》2007,77(5):132-135
Valentina Croci kicks off a new series on interactive technologies with an investigation of the integrated, interdisciplinary research of the new media artist Brigitta Zics. Zics' projects throw light on how conventional architecture might learn from the interactive, placing a greater understanding on the sensory and the user's perceptual experience of a particular space. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
945.
This study was motivated by experimental problems arising in the design of optical digital interferometry for measurements of Soret coefficients in laboratory conditions. Our attention is mainly focused on thermal design of the set-up. The goal is to establish a linear temperature profile inside the experimental cell while heating from above. The measures for preventing deleterious convection inside the working liquid and outside the experimental cell (in the surrounding gas) are carefully examined. It is pointed out that both convection in the liquid and in the surrounding gas have a strong negative effect on the quality of optical measurements. 相似文献
946.
A. L. Lapidus A. Yu. Krylova B. P. Tonkonogov 《Chemistry and Technology of Fuels and Oils》2000,36(2):82-88
Natural gas is increasingly widely used in energetics and industry. In the world energy balance, its share was almost equal
to petroleum’s. Explored gas reserves constitute 60 trillion m3, and 40% are in Russia and CIS countries. Gas chemistry processes using natural and associated petroleum gases to prepare
practically important chemical compounds began to be developed intensively in the second half of the 20th century.
Translated fromKhimiya i Tekhnologiya Topliv i Masel, No. 2, pp. 15 – 19, March – April, 2000. 相似文献
947.
Jelena Popov Valentina Caputi Nandini Nandeesha David Avelar Rodriguez Nikhil Pai 《International journal of molecular sciences》2021,22(21)
Ulcerative colitis (UC) is a chronic autoimmune disorder affecting the colonic mucosa. UC is a subtype of inflammatory bowel disease along with Crohn’s disease and presents with varying extraintestinal manifestations. No single etiology for UC has been found, but a combination of genetic and environmental factors is suspected. Research has focused on the role of intestinal dysbiosis in the pathogenesis of UC, including the effects of dysbiosis on the integrity of the colonic mucosal barrier, priming and regulation of the host immune system, chronic inflammation, and progression to tumorigenesis. Characterization of key microbial taxa and their implications in the pathogenesis of UC and colitis-associated cancer (CAC) may present opportunities for modulating intestinal inflammation through microbial-targeted therapies. In this review, we discuss the microbiota-immune crosstalk in UC and CAC, as well as the evolution of microbiota-based therapies. 相似文献
948.
Alessandro De Vita Silvia Vanni Valentina Fausti Claudia Cocchi Federica Recine Giacomo Miserocchi Chiara Liverani Chiara Spadazzi Massimo Bassi Manlio Gessaroli Angelo Campobassi Giovanni De Luca Federica Pieri Anna Farnedi Eugenia Franchini Anna Ferrari Chiara Domizio Enrico Cavagna Lorena Gurrieri Alberto Bongiovanni Nada Riva Sebastiano Calpona Giandomenico Di Menna Silvia Angela Debonis Toni Ibrahim Laura Mercatali 《International journal of molecular sciences》2021,22(21)
Adult rhabdomyosarcoma (RMS) represents an uncommon entity with an incidence of less than 3% of all soft tissue sarcomas (STS). Consequently, the natural history and the clinical management of this disease are infrequently reported. In order to fill this gap, we investigated the molecular biology of an adult RMS case series. The expression of epithelial mesenchymal transition-related gene and chemoresistance-related gene panels were evaluated. Moreover, taking advantage of our STS translational model combining patient-derived primary culture and 3D-scaffold, the pharmacological profile of an adult head and neck sclerosing RMS was assessed. Furthermore, NGS, microsatellite instability, and in silico analyses were carried out. RT-PCR identified the upregulation of CDH1, SLUG, MMP9, RAB22a, S100P, and LAPTM4b, representing promising biomarkers for this disease. Pharmacological profiling showed the highest sensitivity with anthracycline-based regimen in both 2D and 3D culture systems. NGS analysis detected RAB3IP-HMGA2 in frame gene rearrangement and FGFR4 mutation; microsatellite instability analysis did not detect any alteration. In silico analysis confirmed the mutation of FGFR4 as a promising marker for poor prognosis and a potential therapeutic target. We report for the first time the molecular and pharmacological characterization of rare entities of adult head and neck and posterior trunk RMS. These preliminary data could shed light on this poorly understood disease. 相似文献
949.
Stefanie Hoyer Valentina Eberlein Gerold Schuler Carola Berking Lucie Heinzerling Niels Schaft Jan Drrie 《International journal of molecular sciences》2021,22(21)
BRAF and MEK inhibitor (BRAFi/MEKi) combinations are currently the standard treatment for patients with BRAFV600 mutant metastatic melanoma. Since the RAS/RAF/MEK/ERK-pathway is crucial for the function of different immune cells, we postulated an effect on their function and thus interference with anti-tumor immunity. Therefore, we examined the influence of BRAFi/MEKi, either as single agent or in combination, on the maturation of monocyte-derived dendritic cells (moDCs) and their interaction with T cells. DCs matured in the presence of vemurafenib or vemurafenib/cobimetinib altered their cytokine secretion and surface marker expression profile. Upon the antigen-specific stimulation of CD8+ and CD4+ T cells with these DCs or with T2.A1 cells in the presence of BRAFi/MEKi, we detected a lower expression of activation markers on and a lower cytokine secretion by these T cells. However, treatment with any of the inhibitors alone or in combination did not change the avidity of CD8+ T cells in peptide titration assays with T2.A1 cells. T-helper cell/DC interaction is a bi-directional process that normally results in DC activation. Vemurafenib and vemurafenib/cobimetinib completely abolished the helper T-cell-mediated upregulation of CD70, CD80, and CD86 but not CD25 on the DCs. The combination of dabrafenib/trametinib affected DC maturation and activation as well as T-cell activation less than combined vemurafenib/cobimetinib did. Hence, for a potential combination with immunotherapy, our data indicate the superiority of dabrafenib/trametinib treatment. 相似文献
950.
Dinko Mitre
i Valentina Hribljan Denis Jage
i Jasmina Isakovi Federica Lamberto Alex Hornszky Melinda Zana Gabor Foldes Barbara Zavan Augustas Pivorinas Salvador Martinez Letizia Mazzini Lidija Radenovic Jelena Milasin Juan Carlos Chachques Leonora Buzanska Min Suk Song Andrs Dinnys 《International journal of molecular sciences》2022,23(2)
From the first success in cultivation of cells in vitro, it became clear that developing cell and/or tissue specific cultures would open a myriad of new opportunities for medical research. Expertise in various in vitro models has been developing over decades, so nowadays we benefit from highly specific in vitro systems imitating every organ of the human body. Moreover, obtaining sufficient number of standardized cells allows for cell transplantation approach with the goal of improving the regeneration of injured/disease affected tissue. However, different cell types bring different needs and place various types of hurdles on the path of regenerative neurology and regenerative cardiology. In this review, written by European experts gathered in Cost European action dedicated to neurology and cardiology-Bioneca, we present the experience acquired by working on two rather different organs: the brain and the heart. When taken into account that diseases of these two organs, mostly ischemic in their nature (stroke and heart infarction), bring by far the largest burden of the medical systems around Europe, it is not surprising that in vitro models of nervous and heart muscle tissue were in the focus of biomedical research in the last decades. In this review we describe and discuss hurdles which still impair further progress of regenerative neurology and cardiology and we detect those ones which are common to both fields and some, which are field-specific. With the goal to elucidate strategies which might be shared between regenerative neurology and cardiology we discuss methodological solutions which can help each of the fields to accelerate their development. 相似文献