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N-glycan analyses may serve uncovering disease-associated biomarkers, as well as for profiling distinctive changes supporting diagnosis of genetic disorders of glycan biosynthesis named congenital disorders of glycosylation (CDG). Strategies based on liquid chromatography (LC) preferentially coupled to electrospray ionization (ESI) - mass spectrometry (MS) have emerged as powerful analytical methods for N-glycan identification and characterization. To enhance detection sensitivity, glycans are commonly labelled with a functional tag prior to LC-MS analysis. Since most derivatization techniques are notoriously time-consuming, some commercial analytical kits have been developed to speed up N-deglycosylation and N-glycan labelling of glycoproteins of pharmaceutical and biological interest such as monoclonal antibodies (mAbs). We exploited the analytical capabilities of RapiFluor-MS (RFMS) to perform, by a slightly modified protocol, a detailed N-glycan characterization of total serum and single serum glycoproteins from specific patients with CDG (MAN1B1-CDG, ALG12-CDG, MOGS-CDG, TMEM199-CDG). This strategy, accomplished by Hydrophilic Interaction Chromatography (HILIC)-UPLC-ESI-MS separation of the RFMS derivatized N-glycans, allowed us to uncover structural details of patients serum released N-glycans, thus extending the current knowledge on glycan profiles in these individual glycosylation diseases. The applied methodology enabled to differentiate in some cases either structural isomers and isomers differing in the linkage type. All the here reported applications demonstrated that RFMS method, coupled to HILIC-UPLC-ESI-MS, represents a sensitive high throughput approach for serum N-glycome analysis and a valuable option for glycan detection and separation particularly for isomeric species. [ABSTRACT FROM AUTHOR]

In the present paper, we endow semi De Morgan logic and a family of its axiomatic extensions with proper multi-type display calculi which are sound, complete, conservative, and enjoy cut elimination and subformula property. Our proposal builds on an algebraic analysis of the variety of semi De Morgan algebras, and applies the guidelines of the multi-type methodology in the design of display calculi. [ABSTRACT FROM AUTHOR]

Considerable concern has emerged for the potential harm in the use of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor inhibitors (ARBs) in COVID-19 patients, given that ACEIs and ARBs may increase the expression of ACE2 receptors that represent the way for coronavirus 2 to entry into the cell and cause severe acute respiratory syndrome. Assess the effect of ACEI/ARBs on outcome in COVID-19 patients. Hospital-based prospective study. A total of 431 patients consecutively presenting at the Emergency Department and found to be affected by COVID-19 were assessed. Relevant clinical and laboratory variables were recorded, focusing on the type of current anti hypertensive treatment. Outcome variables were NO, MILD, SEVERE respiratory distress (RD) operationally defined and DEATH. Hypertension was the single most frequent comorbidity (221/431 = 51%). Distribution of antihypertensive treatment was: ACEIs 77/221 (35%), ARBs 63/221 (28%), OTHER than ACEIs or ARBs 64/221 (29%). In 17/221 (8%) antihypertensive medication was unknown. The proportion of patients taking ACEIs, ARBs or OTHERs who developed MILD or SEVERE RD was 43/77 (56%), 33/53 (52%), 39/64 (61%) and 19/77 (25%), 16/63 (25%) and 16/64 (25%), respectively, with no statistical difference between groups. Despite producing a RR for SEVERE RD of 2.59 (95% CI 1.93–3.49), hypertension was no longer significant in a logistic regression analysis that identified age, CRP and creatinine as the sole independent predictors of SEVERE RD and DEATH. ACEIs and ARBs do not promote a more severe outcome of COVID-19. There is no reason why they should be withheld in affected patients. [ABSTRACT FROM AUTHOR]

Congenital disorders of glycosylation (CDG) are genetic diseases characterized by deficient synthesis (CDG type I) and/or abnormal processing (CDG type II) of glycan moieties linked to protein and lipids. The impact of the molecular defects on protein glycosylation and in turn on the clinical phenotypes of patients with CDG is not yet understood. ALG12-CDG is due to deficiency of ALG12 α1,6-mannosyltransferase that adds the eighth mannose residue on the dolichol-PP-oligosaccharide precursor in the endoplasmic reticulum. ALG12-CDG is a severe multisystem disease associated with low to deficient serum immunoglobulins and recurrent infections. We thoroughly investigated the glycophenotype in a patient with novel ALG12 variants and immunodeficiency. We analyzed serum native transferrin, as first line test for CDG and we profiled serum IgG and total serum N-glycans by a combination of consolidated (N-glycan analysis by MALDI MS) and innovative mass spectrometry-based protocols, such as GlycoWorks RapiFluor N-glycan analysis coupled with LC-ESI MS. Intact serum transferrin showed, as expected for a CDG type I defect, underoccupancy of N-glycosylation sites. Surprisingly, total serum proteins and IgG N-glycans showed some specific changes, consisting in accumulating amounts of definite high-mannose and hybrid structures. As a whole, ALG12-CDG behaves as a dual CDG (CDG-I and II defects) and it is associated with distinct, abnormal glycosylation of total serum and IgG N-glycans. Glycan profiling of target glycoproteins may endorse the molecular defect unraveling the complex clinical phenotype of CDG patients. [ABSTRACT FROM AUTHOR]

In Palmigiano and Re (J Pure Appl Algebra 215(8):1945-1957, ), spatial SGF-quantales are axiomatically introduced and proved to be representable as sub unital involutive quantales of quantales arising from set groupoids. In the present paper, spatial SGF-quantales of this class are shown to be optimally representable as unital involutive quantales of relations. The results of the present paper have several aspects in common with Jónsson and Tarski's representation theory for relation algebras (Jónsson and Tarski, Am J Math 74(2):127-162, ). [ABSTRACT FROM AUTHOR]

A join-completion of a poset is a completion for which each element is obtainable as a supremum, or join, of elements from the original poset. It is well known that the join-completions of a poset are in one-to-one correspondence with the closure systems on the lattice of up-sets of the poset. A Δ-completion of a poset is a completion for which, simultaneously, each element is obtainable as a join of meets of elements of the original poset and as a meet of joins of elements from the original poset. We show that Δ-completions are in one-to-one correspondence with certain triples consisting of a closure system of down-sets of the poset, a closure system of up-sets of the poset, and a binary relation between these two systems. Certain Δ-completions, which we call compact, may be described just by a collection of filters and a collection of ideals, taken as parameters. The compact Δ-completions of a poset include its MacNeille completion and all its join- and all its meet-completions. These completions also include the canonical extension of the given poset, a completion that encodes the topological dual of the poset when it has one. Finally, we use our parametric description of Δ-completions to compare the canonical extension to other compact Δ-completions identifying its relative merits. [ABSTRACT FROM AUTHOR]

We associate a canonical unital involutive quantale to a topological groupoid. When the groupoid is also étale, this association is compatible with but independent from the theory of localic étale groupoids and their quantales [9] of P. Resende. As a motivating example, we describe the connection between the quantale and the C*-algebra that both classify Penrose tilings, which was left as an open problem in [5]. [ABSTRACT FROM AUTHOR]

We employ the theory of canonical extensions to study residuation algebras whose associated relational structures are functional, i.e., for which the ternary relations associated to the expanded operations admit an interpretation as (possibly partial) functions. Providing a partial answer to a question of Gehrke, we demonstrate that functionality is not definable in the language of residuation algebras (or even residuated lattices), in the sense that no equational or quasi-equational condition in the language of residuation algebras is equivalent to the functionality of the associated relational structures. Finally, we show that the class of Boolean residuation algebras such that the atom structures of their canonical extensions are functional generates the variety of Boolean residuation algebras. [ABSTRACT FROM AUTHOR]

A molecular tool has been developed for the molecular identification of Ips sexdentatus (Börner 1776) (Coleoptera Curculionidae Scolytidae), the well-known six thooted bark beetle, widely distributed in Eurasia, where it infests several species of the genus Pinus and occasionally a few conifer species of the genera Abies, Larix and Picea. The developed test can be useful both in countries where I. sexdentatus is handled as a quarantine species and, to greater reason, in Europe to discriminate biological traces of this commonly found beetle from those produced by regulated pests. The protocol is based on real-time PCR with TaqMan probe technology and has been developed on whole insect bodies (adults) as well as on artificial frass contaminated by DNA of the beetle. The molecular test developed here for both direct and indirect identification of I. sexdentatus has proven effective in terms of analytical specificity, analytical sensitivity, reliability and reproducibility. The recommended protocol is a practical diagnostic tool allowing a rapid identification of the six toothed bark beetle in the presence of any biological trace of other xylophagous pests collected at points of entry during phytosanitary surveys. [ABSTRACT FROM AUTHOR]