323 research outputs found

    Analysis of Hybrid Air Vehicles using Computational Fluid Dynamics

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    This paper presents an aerodynamic study of bodies related to lighter than air vehicles, using Computational Fluid Dynamics. The work begins with the validation of the CFD method using a 6:1 prolate spheroid. The validated method is then employed for the study of the flow around a shape similar to the Airlander aircraft of Hybrid Air Vehicles Ltd. An overview of the flow around is presented, supported by pressure survey, flow visualisation and transitional flow effects. The sensitivity of the transition location to the Reynolds number is also demonstrated, and the role of each component of the vehicle is analysed in terms of its effect on the flow-field, the lift and drag, and stability in pitch. It was found that the fins contributed the most to increase the lift and drag coefficients

    Sar analysis of small molecules interfering with energy-metabolism in mycobacterium tuberculosis

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    Tuberculosis remains the world’s top infectious killer: it caused a total of 1.5 million deaths and 10 million people fell ill with TB in 2018. Thanks to TB diagnosis and treatment, mortality has been falling in recent years, with an estimated 58 million saved lives between 2000 and 2018. However, the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) Mtb strains is a major concern that might reverse this progress. Therefore, the development of new drugs acting upon novel mechanisms of action is a high priority in the global health agenda. With the approval of bedaquiline, which targets mycobacterial energy production, and delamanid, which targets cell wall synthesis and energy production, the energy-metabolism in Mtb has received much attention in the last decade as a potential target to investigate and develop new antimycobacterial drugs. In this review, we describe potent anti-mycobacterial agents targeting the energy-metabolism at different steps with a special focus on structure-activity relationship (SAR) studies of the most advanced compound classes

    Cyclooxygenase-2 inhibitors. 1,5-diarylpyrrol-3-acetic esters with enhanced inhibitory activity toward cyclooxygenase-2 and improved cyclooxygenase-2/cyclooxygenase-1 selectivity.

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    he important role of cyclooxygenase-2 (COX-2) in the pathogenesis of inflammation and side effect limitations of current COX-2 inhibitor drugs illustrates a need for the design of new compounds based on alternative structural templates. We previously reported a set of substituted 1,5-diarylpyrrole derivatives, along with their inhibitory activity toward COX enzymes. Several compounds proved to be highly selective COX-2 inhibitors and their affinity data were rationalized through docking simulations. In this paper, we describe the synthesis of new 1,5-diarylpyrrole derivatives that were assayed for their in vitro inhibitory effects toward COX isozymes. Among them, the ethyl-2-methyl-5-[4-(methylsulfonyl)phenyl]-1-[3-fluorophenyl]-1H-pyrrol-3- acetate (1d), which was the most potent and COX-2 selective compound, also showed a very interesting in vivo anti-inflammatory and analgesic activity, laying the foundations for developing new lead compounds that could be effective agents in the armamentarium for the management of inflammation and pain

    Flow synthesis and biological studies of an analgesic adamantane derivative that inhibits P2X7-evoked glutamate release

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    We report the biological evaluation of a class of adamantane derivatives, which were achieved via modified telescoped machine-assisted flow procedure. Among the series of compounds tested in this work, 5 demonstrated outstanding analgesic properties. This compound showed that its action was not mediated through direct interaction with opioid and/or cannabinoid receptors. Moreover, it did not display any significant anti-inflammatory properties. Experiments carried out on rat cerebrocortical purified synaptosomes indicated that 5 inhibits the P2X7-evoked glutamate release, which may contribute to its antinociceptive properties. Nevertheless, further experiments are ongoing to characterize the pharmacological properties and mechanism of action of this molecule

    Synthesis and biological evaluation of fluorinated 1,5-diarylpyrrole-3-alkoxyethyl ether derivatives as selective COX-2 inhibitors endowed with anti-inflammatory activity

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    A series of substituted 1,5-diarylpyrrole-3-alkoxyethyl ethers were previously synthesized and the potential anti-inflammatory and antinociceptive activities of these compounds were evaluated in vivo. The compounds displayed a very good activity against both carrageenan-induced hyperalgesia and oedema in the rat paw test. Therefore, in a very preliminary test, compounds (8a,b) showed antiproliferative activity in the HaCaT (aneuploid immortal keratinocyte from adult human skin) cell models. On these basis, our research continued with the synthesis of fluorinated derivatives (8c,d, 9b-d, and 10b-d) with the aim of improving the pharmacokinetic profile of the previous active compounds. Substitution of a hydrogen atom by a fluorine atom may change the conformational preferences of the molecules due to stereoelectronic effects and also fluorine atom may be able to exert the metabolic obstruction reducing the "first-pass effect". Compound 10b exhibited a prominent in vivo anti-inflammatory and antinociceptive activities, in addition its antiproliferative power in an in vitro model of human skin cancer is herein described

    Synthesis and biological evaluation of fluorinated 1,5-diarylpyrrole-3-alkoxyethyl ether derivatives as selective COX-2 inhibitors endowed with anti-inflammatory activity

    Get PDF
    A series of substituted 1,5-diarylpyrrole-3-alkoxyethyl ethers were previously synthesized and the potential anti-inflammatory and antinociceptive activities of these compounds were evaluated in vivo. The compounds displayed a very good activity against both carrageenan-induced hyperalgesia and oedema in the rat paw test. Therefore, in a very preliminary test, compounds (8a,b) showed antiproliferative activity in the HaCaT (aneuploid immortal keratinocyte from adult human skin) cell models. On these basis, our research continued with the synthesis of fluorinated derivatives (8c,d, 9b-d, and 10b-d) with the aim of improving the pharmacokinetic profile of the previous active compounds. Substitution of a hydrogen atom by a fluorine atom may change the conformational preferences of the molecules due to stereoelectronic effects and also fluorine atom may be able to exert the metabolic obstruction reducing the "first-pass effect". Compound 10b exhibited a prominent in vivo anti-inflammatory and antinociceptive activities, in addition its antiproliferative power in an in vitro model of human skin cancer is herein described

    Postmortem Findings in Italian Patients With COVID-19: A Descriptive Full Autopsy Study of Cases With and Without Comorbidities

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    BACKGROUND: Descriptions of the pathological features of coronavirus disease-2019 (COVID-19) caused by the novel zoonotic pathogen severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emanate from tissue biopsies, case reports, and small postmortem studies restricted to the lung and specific organs. Whole-body autopsy studies of COVID-19 patients have been sparse. METHODS: To further define the pathology caused by SARS-CoV-2 across all body organs, we performed autopsies on 22 patients with COVID-19 (18 with comorbidities and 4 without comorbidities) who died at the National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS Hospital, Rome, Italy. Tissues from the lung, heart, liver, kidney, spleen, and bone marrow (but not the brain) were examined. Only lung tissues were subject to transmission electron microscopy. RESULTS: COVID-19 caused multisystem pathology. Pulmonary and cardiovascular involvement were dominant pathological features. Extrapulmonary manifestations included hepatic, kidney, splenic, and bone marrow involvement, and microvascular injury and thrombosis were also detected. These findings were similar in patients with or without preexisting medical comorbidities. CONCLUSIONS: SARS-CoV-2 infection causes multisystem disease and significant pathology in most organs in patients with and without comorbidities

    Detection of Viral RNA in Tissues following Plasma Clearance from an Ebola Virus Infected Patient

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    An unprecedented Ebola virus (EBOV) epidemic occurred in 2013–2016 in West Africa. Over this time the epidemic exponentially grew and moved to Europe and North America, with several imported cases and many Health Care Workers (HCW) infected. Better understanding of EBOV infection patterns in different body compartments is mandatory to develop new countermeasures, as well as to fully comprehend the pathways of human-to-human transmission. We have longitudinally explored the persistence of EBOV-specific negative sense genomic RNA (neg-RNA) and the presence of positive sense RNA (pos-RNA), including both replication intermediate (antigenomic-RNA) and messenger RNA (mRNA) molecules, in the upper and lower respiratory tract, as compared to plasma, in a HCW infected with EBOV in Sierra Leone, who was hospitalized in the high isolation facility of the National Institute for Infectious Diseases “Lazzaro Spallanzani” (INMI), Rome, Italy. We observed persistence of pos-RNA and neg-RNAs in longitudinally collected specimens of the lower respiratory tract, even after viral clearance from plasma, suggesting possible local replication. The purpose of the present study is to enhance the knowledge on the biological features of EBOV that can contribute to the human-to-human transmissibility and to develop effective intervention strategies. However, further investigation is needed in order to better understand the clinical meaning of viral replication and shedding in the respiratory tract
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