231 research outputs found
On the Correspondence between Display Postulates and Deep Inference in Nested Sequent Calculi for Tense Logics
We consider two styles of proof calculi for a family of tense logics,
presented in a formalism based on nested sequents. A nested sequent can be seen
as a tree of traditional single-sided sequents. Our first style of calculi is
what we call "shallow calculi", where inference rules are only applied at the
root node in a nested sequent. Our shallow calculi are extensions of Kashima's
calculus for tense logic and share an essential characteristic with display
calculi, namely, the presence of structural rules called "display postulates".
Shallow calculi enjoy a simple cut elimination procedure, but are unsuitable
for proof search due to the presence of display postulates and other structural
rules. The second style of calculi uses deep-inference, whereby inference rules
can be applied at any node in a nested sequent. We show that, for a range of
extensions of tense logic, the two styles of calculi are equivalent, and there
is a natural proof theoretic correspondence between display postulates and deep
inference. The deep inference calculi enjoy the subformula property and have no
display postulates or other structural rules, making them a better framework
for proof search
Automated Synthesis of Tableau Calculi
This paper presents a method for synthesising sound and complete tableau
calculi. Given a specification of the formal semantics of a logic, the method
generates a set of tableau inference rules that can then be used to reason
within the logic. The method guarantees that the generated rules form a
calculus which is sound and constructively complete. If the logic can be shown
to admit finite filtration with respect to a well-defined first-order semantics
then adding a general blocking mechanism provides a terminating tableau
calculus. The process of generating tableau rules can be completely automated
and produces, together with the blocking mechanism, an automated procedure for
generating tableau decision procedures. For illustration we show the
workability of the approach for a description logic with transitive roles and
propositional intuitionistic logic.Comment: 32 page
Transient glyco-engineering to produce recombinant IgA1 with defined N-and O-glycans in plants
[EN] The production of therapeutic antibodies to combat pathogens and treat diseases, such
as cancer is of great interest for the biotechnology industry. The recent development of
plant-based expression systems has demonstrated that plants are well-suited for the
production of recombinant monoclonal antibodies with defined glycosylation. Compared
to immunoglobulin G (IgG), less effort has been undertaken to express immunoglobulin
A (IgA), which is the most prevalent antibody class at mucosal sites and a promising
candidate for novel recombinant biopharmaceuticals with enhanced anti-tumor activity.
Here, we transiently expressed recombinant human IgA1 against the VP8* rotavirus
antigen in glyco-engineered XT/FT Nicotiana benthamiana plants. Mass spectrometric
analysis of IgA1 glycopeptides revealed the presence of complex biantennary N-glycans
with terminal N-acetylglucosamine present on the N-glycosylation site of the CH2
domain in the IgA1 alpha chain. Analysis of the peptide carrying nine potential
O-glycosylation sites in the IgA1 alpha chain hinge region showed the presence of
plant-specific modifications including hydroxyproline formation and the attachment of
pentoses. By co-expression of enzymes required for initiation and elongation of human
O-glycosylation it was possible to generate disialylated mucin-type core 1 O-glycans on
plant-produced IgA1. Our data demonstrate that XT/FT N. benthamiana plants can
be engineered toward the production of recombinant IgA1 with defined human-type Nand
O-linked glycans.This work was supported by a grant from the Austrian Federal Ministry of Transport, Innovation and Technology (bmvit) and Austrian Science Fund (FWF): TRP 242-B20 and by the Austrian Research Promotion Agency (Laura Bassi Center of Expertise "Plant produced Bio-Pharmaceuticals" Grant Nr. 822757).Dicker, M.; Tschofen, M.; Maresch, D.; Koenig, J.; Juarez, P.; Orzáez Calatayud, DV.; Altmann, F.... (2016). Transient glyco-engineering to produce recombinant IgA1 with defined N-and O-glycans in plants. Frontiers in Plant Science. 7(18):1-12. https://doi.org/10.3389/fpls.2016.00018S11271
Metabolic profiling and antibacterial activity of Eryngium pristis Cham. & Schltdl. - prospecting for its use in the treatment of bacterial infections
Morbidity and mortality of the infected patients by multidrug-resistant bacteria have increased, emphasizing
the urgency of fi ght for the discovery of new innovative antibiotics. In this sense, natural products emerge as
valuable sources of bioactive compounds. Among the biodiversity, Eryngium pristis Cham. & Schltdl. (Apiaceae
Lindl.) is traditionally used to treat thrush and ulcers of throat and mouth, as diuretic and emmenagogue, but
scarcely known as an antimicrobial agent. With this context in mind, the goals of this study were to investigate the
metabolic profi le and the antibacterial activity of ethanolic extract (EE-Ep) and hexane (HF-Ep), dichloromethane
(DF-Ep), ethyl acetate (EAF-Ep) and butanol (BF-Ep) fractions from E. pristis leaves. Gas Chromatography-Mass
Spectrometry (GC-MS) was performed to stablish the metabolic profi le and revealed the presence of 12 and
14 compounds in EAF-Ep and HF-Ep, respectively. β-selinene, spathulenol, globulol, 2-methoxy-4-vinylphenol,
α-amyrin, β-amyrin, and lupeol derivative were some of phytochemicals identifi ed. The antibacterial activity was
determined by Minimal Inhibitory Concentration (MIC) using the broth micro-dilution against eight ATCC® and
fi ve methicillin-resistant Staphylococcus aureus (MRSA) clinical strains. HF-Ep was the most eff ective (MIC ≤
5,000 ÎĽg/ÎĽL), being active against the largest part of tested Gram-positive and Gram-negative bacterial strains,
including MRSA, with exception of Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 9027)
and (ATCC 27853). These results suggest that E. pristis is a natural source of bioactive compounds for the
search of new antibiotics which can be an interesting therapeutic approach to recover patients mainly infected
by MRSA strains.info:eu-repo/semantics/publishedVersio
Pioderma gangrenoso secundário à infecção por Sarcoptes Scabei: relato de caso
O Pioderma Gangrenoso Ă© considerado uma dermatose inflamatĂłria de baixa prevalĂŞncia, com clĂnica de lesões ulcerosas, pustulosas, bolhosas ou vegetantes dispersas pelo corpo. Geralmente sĂŁo crĂ´nicas e podem simular outras lesões, sendo difĂcil seu diagnĂłstico. Sua causa pode ser primária idiopática ou secundária Ă outras patologias, principalmente autoimunes, como a Doença de Crohn e algumas Artrites. Seu diagnĂłstico pode ser feito por exame anatomopatolĂłgico da lesĂŁo ou exclusĂŁo de outras afecções dermatolĂłgicas de clĂnica semelhante. Relata-se um caso de apresentação atĂpica de Pioderma Gangrenoso secundário a escabiose, em paciente do sexo masculino, 73 anos, com queixa de prurido em membros superiores, tronco e abdome, associado Ă lesões ulceradas em membros inferiores. As hipĂłteses diagnĂłsticas iniciais foram farmacodermia, porfiria cutânea tarda, escabiose associada Ă ectima, pĂŞnfigo bolhoso ou “PLECTS” (paracoccidioidomicose, leishmaniose, esporotricose, cromomicose, tuberculose cutânea). Feito biĂłpsia das lesões cujo diagnĂłstico foi Pioderma Gangrenoso secundário Ă infecção por Sarcoptes scabiei. Por ser uma afecção dermatolĂłgica rara, idiopática e muitas vezes de causa secundária; torna-se cada vez mais importante o diagnĂłstico precoce da lesĂŁo para o sucesso do seu tratamento
GoldenBraid: An Iterative Cloning System for Standardized Assembly of Reusable Genetic Modules
Synthetic Biology requires efficient and versatile DNA assembly systems to facilitate the building of new genetic modules/pathways from basic DNA parts in a standardized way. Here we present GoldenBraid (GB), a standardized assembly system based on type IIS restriction enzymes that allows the indefinite growth of reusable gene modules made of standardized DNA pieces. The GB system consists of a set of four destination plasmids (pDGBs) designed to incorporate multipartite assemblies made of standard DNA parts and to combine them binarily to build increasingly complex multigene constructs. The relative position of type IIS restriction sites inside pDGB vectors introduces a double loop (“braid”) topology in the cloning strategy that allows the indefinite growth of composite parts through the succession of iterative assembling steps, while the overall simplicity of the system is maintained. We propose the use of GoldenBraid as an assembly standard for Plant Synthetic Biology. For this purpose we have GB-adapted a set of binary plasmids for A. tumefaciens-mediated plant transformation. Fast GB-engineering of several multigene T-DNAs, including two alternative modules made of five reusable devices each, and comprising a total of 19 basic parts are also described
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