291 research outputs found

    Molecular Carbon Chains and Rings in TMC-1

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    We present mapping results in several rotational transitions of HC3N, C6H, both cyclic and linear C3H2 and C3H, towards the cyanopolyyne peak of the filamentary dense cloud TMC-1 using the IRAM 30m and MPIfR 100m telescopes. The spatial distribution of the cumulene carbon chain propadienylidene H2C3 (hereafter l-C3H2) is found to deviate significantly from the distributions of the cyclic isomer c-C3H2, HC3N, and C6H which in turn look very similar. The cyclic over linear abundance ratio of C3H2 increases by a factor of 3 across the filament, with a value of 28 at the cyanopolyyne peak. This abundance ratio is an order of magnitude larger than the range (3 to 5) we observed in the diffuse interstellar medium. The cyclic over linear abundance ratio of C3H also varies by ~2.5 in TMC-1, reaching a maximum value (13) close to the cyanopolyyne peak. These behaviors might be related to competitive processes between ion-neutral and neutral-neutral reactions for cyclic and linear species.Comment: Accepted for publication in The Astrophysical Journal, part I. 24 pages, including 4 tables, 7 figures, and figure caption

    Biodistribution et toxicité des nanocapsules chargées en 188Re aprÚs injection intratumorale par convection enhanced delivery chez la souris

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    Objectifs DĂ©terminer la faisabilitĂ©, l’intĂ©rĂȘt et la toxicitĂ© hĂ©matologique de l’administration intratumorale par convection enhanced delivery (CED) de nanocapsules chargĂ©es en 188Re (NCL-188Re). MatĂ©riels et mĂ©thodes L’étude de biodistribution des NCL-188Re vs perrhĂ©nate (188ReO4−) a Ă©tĂ© rĂ©alisĂ©e sur des souris nude (n = 30). Les animaux ont Ă©tĂ© sĂ©parĂ©s en 2 groupes : injection intratumorale de 188ReO4− pour le premier groupe (n = 15, 3 MBq) et de NCL-188Re pour le second groupe (n = 15, 3 MBq). Les animaux ont Ă©tĂ© sacrifiĂ©s Ă  1 h (n = 10), 24 h (n = 10) et 72 h (n = 10) aprĂšs l’injection, les organes prĂ©levĂ©s et comptĂ©s. La toxicitĂ© hĂ©matologique des NCL-188Re a Ă©tĂ© Ă©valuĂ©e par prises de sang de 50 ΌL (sinus rĂ©tro-orbitaire) rĂ©alisĂ©es Ă  j2, j7, j14 et j21 aprĂšs traitement par NaCl (n = 4), NCL-188Re (3 MBq, n = 4), NCL-188Re (6 MBq, n = 4) et NCL-188Re (12 MBq, n = 4). RĂ©sultats La vectorisation par NCL a permis de limiter l’élimination urinaire du 188Re puisque dĂšs 24 h post-IV 0,1 ± 0,1 % de la dose injectĂ©e (%D.I.) vs 81,9 ± 7,5 % D.I. sont retrouvĂ©s dans les urines pour les formes NCL188Re-SSS et 188ReO4-, respectivement, (p = 0,016). Celle-ci permet Ă©galement de retrouver une activitĂ© significativement supĂ©rieure dans la tumeur Ă  tous les temps de l’étude. L’administration unique de NCL-188Re a induit une toxicitĂ© modĂ©rĂ©e pour les activitĂ©s injectĂ©es les plus Ă©levĂ©es (12 MBq) se manifestant principalement par une thrombopĂ©nie transitoire de nadir j14–j18. Il n’a pas Ă©tĂ© observĂ© de toxicitĂ© au niveau des autres lignĂ©es cellulaires pour les activitĂ©s administrĂ©es de 3 et 6 MBq. Conclusions Les rĂ©sultats obtenus montrent la faisabilitĂ© de l’injection intratumorale par CED et l’intĂ©rĂȘt de la vectorisation du 188Re par les NCL. Les premiers signes de toxicitĂ© hĂ©matologiques sont en faveur du fractionnement des doses administrĂ©es et d’un meilleur ciblage par fonctionnalisation des NCL aux oestrogĂšnes pour permettre une meilleure rĂ©tention tumorale

    Revisiting the S-matrix approach to the open superstring low energy effective lagrangian

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    The conventional S-matrix approach to the (tree level) open string low energy effective lagrangian assumes that, in order to obtain all its bosonic αâ€ČN{\alpha'}^N order terms, it is necessary to know the open string (tree level) (N+2)(N+2)-point amplitude of massless bosons, at least expanded at that order in αâ€Č\alpha'. In this work we clarify that the previous claim is indeed valid for the bosonic open string, but for the supersymmetric one the situation is much more better than that: there are constraints in the kinematical bosonic terms of the amplitude (probably due to Spacetime Supersymmetry) such that a much lower open superstring nn-point amplitude is needed to find all the αâ€ČN{\alpha'}^N order terms. In this `revisited' S-matrix approach we have checked that, at least up to αâ€Č4{\alpha'}^4 order, using these kinematical constraints and only the known open superstring 4-point amplitude, it is possible to determine all the bosonic terms of the low energy effective lagrangian. The sort of results that we obtain seem to agree completely with the ones achieved by the method of BPS configurations, proposed about ten years ago. By means of the KLT relations, our results can be mapped to the NS-NS sector of the low energy effective lagrangian of the type II string theories implying that there one can also find kinematical constraints in the NN-point amplitudes and that important informations can be inferred, at least up to αâ€Č4{\alpha'}^4 order, by only using the (tree level) 4-point amplitude.Comment: 34 pages, 3 figure, Submitted on Aug 4, 2012, Published on Oct 15, 201

    Fischer carbene mediated covalent grafting of a peptide nucleic acid on gold surfaces and IR optical detection of DNA hybridization with a transition metalcarbonyl label

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    Amine-reactive surfaces comprising N-hydroxysuccinimide ester groups as well as much more unusual Fischer alkoxymetallocarbene groups were generated on gold-coated surfaces via self-assembled monolayers of carboxy- and azido-terminated thiolates, respectively. These functions were further used to immobilize homothymine peptide nucleic acid (PNA) decamer in a covalent fashion involving the primary amine located at its N-terminus. These stepwise processes were monitored by polarization modulation reflection - absorption infrared spectroscopy (PM-RAIRS) that gave useful information on the molecular composition of the organic layers. PNA grafting and hybridization with complementary DNA strand were successfully transduced by quartz crystal microbalance (QCM) measurements. Unfortunately, attempts to transduce the hybridization optically by IR in a label-free fashion were inconclusive. Therefore we undertook to introduce an IR reporter group, namely a transition metalcarbonyl (TMC) entity at the 5\u2032 terminus of complementary DNA. Evidence for the formation of PNA-DNA heteroduplex was brought by the presence of \u3bd(C 61O) bands in the 2000 cm-1 region of the IR spectrum of the gold surface owing to the metalcarbonyl label

    Reading performance with various lamps in age-related macular degeneration

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    The purpose of this study was to determine if there was an objective difference in reading between four commonly available lamps, of varying spectral radiance, for 13 subjects with age-related maculopathy (ARM) or non-exudative age-related macular degeneration (AMD) - logMAR visual acuity between 0.04 and 0.68. At a constant illuminance of 2000 lux, there was no interaction between ARM and AMD subgroups and no statistically significant difference between the lamps: standard (clear envelope) incandescent, daylight simulation (blue tint envelope) incandescent, compact fluorescent and halogen incandescent, for any reading outcome measure (threshold print size p = 0.67, critical print size p = 0.74, acuity reserve p = 0.84 and mean reading rate p = 0.78). For lamps typically used in low-vision rehabilitation, a clinically significant effect of spectral radiance on reading for people with ARM or non-exudative AMD is unlikely. © 2007 The College of Optometrists

    Nucleic Acids Res

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    The HIV-1 transactivator of transcription (Tat) protein is thought to stimulate reverse transcription (RTion). The Tat protein and, more specifically, its (44-61) domain were recently shown to promote the annealing of complementary DNA sequences representing the HIV-1 transactivation response element TAR, named dTAR and cTAR, that plays a key role in RTion. Moreover, the kinetic mechanism of the basic Tat(44-61) peptide in this annealing further revealed that this peptide constitutes a representative nucleic acid annealer. To further understand the structure-activity relationships of this highly conserved domain, we investigated by electrophoresis and fluorescence approaches the binding and annealing properties of various Tat(44-61) mutants. Our data showed that the Tyr47 and basic residues of the Tat(44-61) domain were instrumental for binding to cTAR through stacking and electrostatic interactions, respectively, and promoting its annealing with dTAR. Furthermore, the annealing efficiency of the mutants clearly correlates with their ability to rapidly associate and dissociate the complementary oligonucleotides and to promote RTion. Thus, transient and dynamic nucleic acid interactions likely constitute a key mechanistic component of annealers and the role of Tat in the late steps of RTion. Finally, our data suggest that Lys50 and Lys51 acetylation regulates Tat activity in RTion

    Italian S3-Guideline on the treatment of Atopic Eczema - Part 1: Systemic therapy, adapted from EuroGuiDerm by the Italian Society of Dermatology and STD (SIDEMAST), the Italian Association of Hospital Dermatologists (ADOI) and the Italian Society of Allergological and Environmental Dermatology (SIDAPA).

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    SIDeMaST (SocietĂ  Italiana di Dermatologia Medica, Chirurgica, Estetica e delle Malattie Sessualmente Trasmesse) contributed to the development of the present guideline on the systemic treatment of chronic plaque psoriasis. With the permission of EuroGuiDerm, SIDeMaST adapted the guideline to the Italian healthcare context to supply a reliable and affordable tool to Italian physicians who take care of patients affected by atopic dermatitis. The evidence- and consensus-based guideline on atopic eczema was developed in accordance with the EuroGuiDerm Guideline and Consensus Statement Development Manual. Four consensus conferences were held between December 2020 and July 2021. Twenty-nine experts (including clinicians and patient representatives) from 12 European countries participated. This ïŹrst part of the guideline includes general information on its scope and purpose, the health questions covered, target users and a methods section. It also provides guidance on which patients should be treated with systemic therapies, as well as recommendations and detailed information on each systemic drug. The systemic treatment options discussed in the guideline comprise conventional immunosuppressive drugs (azathioprine, ciclosporin, glucocorticosteroids, methotrexate and mycophenolate mofetil), biologics (dupilumab, lebrikizumab, nemolizumab, omalizumab and tralokinumab) and janus kinase inhibitors (abrocitinib, baricitinib and upadacitinib). Part two of the guideline will address avoidance of provocation factors, dietary interventions, immunotherapy, complementary medicine, educational interventions, occupational and psychodermatological aspects, patient perspective and considerations for pediatric, adolescent, pregnant and breastfeeding patients

    Italian S3-Guideline on the treatment of Atopic Eczema - Part 2: non-systemic treatments and treatment recommendations for special AE patient populations, adapted from EuroGuiDerm by the Italian Society of Dermatology and STD (SIDEMAST), the Italian Association of Hospital Dermatologists (ADOI) and the Italian Society of Allergological and Occupational Dermatology (SIDAPA).

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    SIDeMaST (SocietĂ  Italiana di Dermatologia Medica, Chirurgica, Estetica e delle Malattie Sessualmente Trasmesse) contributed to the development of the present guideline on the systemic treatment of chronic plaque psoriasis. With the permission of EuroGuiDerm, SIDeMaST adapted the guideline to the Italian healthcare context to supply a reliable and affordable tool to Italian physicians who take care of patients affected by atopic dermatitis. The evidence- and consensus-based guideline on atopic eczema was developed in accordance with the EuroGuiDerm Guideline and Consensus Statement Development Manual. Four consensus conferences were held between December 2020 and July 2021. Twenty-nine experts (including clinicians and patient representatives) from 12 European countries participated. This second part of the guideline includes recommendations and detailed information on basic therapy with emollients and moisturizers, topical anti-inïŹ‚ammatory treatment, antimicrobial and antipruritic treatment and UV phototherapy. Furthermore, this part of the guideline covers techniques for avoiding provocation factors, as well as dietary interventions, immunotherapy, complementary medicine and educational interventions for patients with atopic eczema and deals with occupational and psychodermatological aspects of the disease. It also contains guidance on treatment for pediatric and adolescent patients and pregnant or breastfeeding women, as well as considerations for patients who want to have a child. A chapter on the patient perspective is also provided. The ïŹrst part of the guideline, published separately, contains recommendations and guidance on systemic treatment with conventional immunosuppressive drugs, biologics and janus kinase (JAK) inhibitors, as well as information on the scope and purpose of the guideline, and a section on guideline methodology
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