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Antibodies to the nucleocapsid (N) antigen are suggested to be used to monitor infections after COVID-19 vaccination, as first generation subunit vaccines are based on the spike (S) protein. We used multiplex immunoassays to simultaneously measure antibody responses to different fragments of the SARS-CoV-2 S and N antigens for evaluating the immunogenicity of the mRNA-1273 (Spykevax) and the BNT162b2 (Comirnaty) vaccines in 445 health care workers. We report a >4-fold increase post-vaccination of IgG levels to the full length (N FL) and C-terminus of N (N CT) in 5.2% and 18.0% of individuals, respectively, and of IgA in 3.6% (N FL) and 9.0% (N CT) of them. The increase in IgG levels and avidity was more pronounced after Spykevax than Comirnaty vaccination (36.2% vs 13.1% for N CT, and 10.6% vs 3.7% for N FL). Data suggest the induction of cross-reactive antibodies against the N CT region after administering these S-based vaccines, and this should be taken into account when using N seropositivity to detect breakthroughs. [ABSTRACT FROM AUTHOR]

In the aftermath of the COVID-19 pandemic, the dynamics of short-term rental demand, particularly on Airbnb, have seen pivotal shifts. Using Madrid as a case study, this research used strategic sampling to investigate changes in occupancy, housing attributes, and online reputation. Leveraging a sup-likelihood ratio test and a hedonic-type pooled panel-data Logit regression, we identified a marked structural break. Findings revealed a diminished demand-side bargaining power, resulting in increased rental prices and reduced information transparency. These results offered critical insights for tourism industry stakeholders, especially destination managers and Airbnb hosts. • Several tests confirm the structural change caused by COVID-19. • The pandemic leads to major shifts in the supply structure and demand preferences. • Demand suffers a loss of bargaining power resulting in higher accommodation prices. • In the face of the new normal tourists pays less attention to previous experiences. • The "HRO" variable complements previous hedonic studies based on users and prices. [ABSTRACT FROM AUTHOR]

COVID-19 patients elicit strong responses to the nucleocapsid (N) protein of SARS-CoV-2 but binding antibodies are also detected in prepandemic individuals, indicating potential crossreactivity with common cold human coronaviruses (HCoV) and questioning its utility in seroprevalence studies. We investigated the immunogenicity of the full-length and shorter fragments of the SARS-CoV-2 N protein, and the crossreactivity of antibodies with HCoV. We identified a C-terminus region in SARS-CoV2 N of minimal sequence homology with HCoV that was more specific for SARS-CoV-2 and highly immunogenic. IgGs to the full-length SARS-CoV-2 N also recognized N229E N, and IgGs to HKU1 N recognized SARS-CoV-2 N. Crossreactivity with SARS-CoV-2 was stronger for alpha- rather than beta-HCoV despite having less sequence identity, revealing the importance of conformational recognition. Higher preexisting IgG to OC43 N correlated with lower IgG to SARS-CoV-2 N in rRT-PCR negative individuals, reflecting less exposure and indicating a potential protective association. Antibodies to SARS-CoV-2 N were higher in patients with more severe and longer duration of symptoms and in females. IgGs remained stable for at least 3 months, while IgAs and IgMs declined faster. In conclusion, N protein is a primary target of SARS-CoV-2-specific and HCoV crossreactive antibodies, both of which may affect the acquisition of immunity to COVID-19. [ABSTRACT FROM AUTHOR]

Malaria, leishmaniasis and trypanosomiasis are arthropod-borne, parasitic diseases that constitute a major global health problem. They are generally found in developing countries, where lack of access to preventive tools and treatment hinders their management. Because these parasites share an increased demand on glucose consumption with most cancer cells, six compounds used in anti-tumoral research were selected to be tested as antiparasitic agents in in vitro models of Leishmania infantum , Trypanosoma brucei, T. cruzi, and Plasmodium falciparum : dichloroacetic acid (DCA), 3-bromopyruvic acid (3BP), 2-deoxy-D-glucose (2DG), lonidamine (LND), metformin (MET), and sirolimus (SIR). No parasite-killing activity was found in L. infantum promastigotes, whereas DCA and 3BP reduced the burden of intra-macrophagic amastigotes. For T. brucei all selected compounds, but 2DG, decreased parasite survival. DCA, 2DG, LND and MET showed parasite-killing activity in T. cruzi. Finally, anti-plasmodial activity was found for DCA, 2DG, LND, MET and SIR. These results reinforce the hypothesis that drugs with proven efficacy in the treatment of cancer by interfering with ATP production, proliferation, and survival cell strategies might be useful in treating threatening parasitic diseases and provide new opportunities for their repurposing. Image 1 • Parasitic diseases are prevalent among the poorest of the poor. • Some parasitic protists degrade glucose into CO 2 even aerobically making this a target. • Degrading glucose into CO 2 (Warburg effect) is also characteristic for cancer cells. • Repurposing cancer glycolysis blockers may provide cost-effective treatments for the poorest. [ABSTRACT FROM AUTHOR]

Like any other microorganism, pathogenic protozoan parasites rely heavily on glycoconjugates and glycan binding proteins to protect themselves from the environment and to interact with their diverse hosts. A thorough comprehension of how glycobiology contributes to the survival and virulence of these organisms may reveal unknown aspects of their biology and may open much needed avenues for the design of new strategies against them. In the case of Plasmodium falciparum , which causes the vast majority of malaria cases and deaths, the restricted variety and the simplicity of its glycans seemed to confer limited significance to the role played by glycoconjugates in the parasite. Nonetheless, the last 10 to 15 years of research are revealing a clearer and more defined picture. Thus, the use of new experimental techniques and the results obtained provide new avenues for understanding the biology of the parasite, as well as opportunities for the development of much required new tools against malaria. • Malaria parasite glycans seem to be of a few kinds, simple and with low variability. • Yet, most of them are critical for parasite development and/or transmission. • Glycans modify important malaria vaccine antigens in different parasite stages. • Still, lifecycle and glycan biosynthesis complexity hinder a better insight. • Despite recent progress, key questions on specific life stages and processes remain. [ABSTRACT FROM AUTHOR]

Abstract Despite the importance of collaborative accommodation in practically every tourist destination, to date the majority of studies have focused on large cities and urban destinations. This article distinguishes the factors that explain the added value of Airbnb properties, differentiating between urban and sun-and-beach holiday destinations. To do this, nine destinations from one of the most important European tourism regions have been studied using a hedonic pricing model that includes some variables related to the characteristics of the properties and others that define the online reputation of the hosts and properties and the tourism environment. The results reveal that the sharing economy fosters the emergence of private rentals, expanding the overall size of the accommodation market with some clear differences between the two types of tourist destinations, which emphasize the idea that the decisions made by stakeholders should be considered from a local perspective. Highlights • Studies nine destinations using a hedonic pricing model. • Distinguishes factors explaining the added value of Airbnb properties. • Tourist experience has a greater influence on pricing in urban destinations. • Finds differences between urban and sun and beach holiday destinations. • Tourism decisions should be considering from a local perspective. [ABSTRACT FROM AUTHOR]

Abstract Catalonia is one of the most successful tourist regions in Spain. This article analyses the immediate impact that the instability associated to the recent political situation in Catalonia has had on the arrivals and spending of international tourists in the region using the classical Box-Jenkins method (ARIMA) and the more recent Bayesian Structural Time-Series Models. The results obtained indicate that during the final quarter of 2017, political events led to a reduction in the arrivals and spending of tourists in the region, although whether this impact reached statistical significance depends on the estimation method used. Highlights • Catalonia is the leading tourism destination in Spain. • We analyse the impact of the political instability in Catalonia's tourism sector. • The results of ARIMA and BSTS techniques are compared. • Political instability negatively affects the performance of tourist destinations. • Bayesian techniques find difficult to get statistically significant impacts. [ABSTRACT FROM AUTHOR]

Since the first paper on the subject was published in 2002, the tourism-led growth hypothesis (TLGH) has constituted one of the most predominant topics in tourism literature. Spain is a leading country in the tourism industry and one where this hypothesis has been tested with several studies confirming the relationship between Spain's tourism development and its economic growth. However, the existing studies for Spain do not take into account recent turbulences such as the Global Financial and Economic Crisis and the Arab Spring uprisings that have shocked tourism markets. This paper re-examines the TLGH for the Spanish case in the light of these events in order to investigate the robustness of the relationship between tourism and economic growth. [ABSTRACT FROM AUTHOR]

The increase of passengers and flights require airports operators invest in improving the comfort for users. In this regard, Information and Communication Technologies (ICTs) represent one of the key issues to take into account. This paper aims to assess service quality in an airport environment and examining how ICTs services affect passenger's perception about the quality of service at airport functional areas. The empirical results, based on a survey conducted by the Chilean aviation authority during April 2013 among the travellers of Santiago de Chile's Airport, suggest that airports should improve mainly the way of communicating flight information to users and the location of the different airport's utilities. Implications for airport managers and policy makers are drawn from the empirical findings and future research lines are suggested. [ABSTRACT FROM AUTHOR]

This paper analyses the effects of economic crises on tourism destinations from a city and regional point of view. The objective is to determine which kind of Spanish “Sun and Beach” tourism destinations, residential or hotel, has better weathered the most recent economic crisis in Spain, linked to the Global Financial Crisis of 2007/8. For this purpose, the authors have analysed the increases in the unemployment rates of a pool of 138 tourist destinations located on the Spanish Mediterranean coastline. The main finding of the paper is that during the crisis, residential destinations experienced a greater destruction of employment than hotel destinations. This result is consistent with previous literature that indicates a better economic performance of the hotel tourism development model. [ABSTRACT FROM AUTHOR]

Abstract: This paper analyses the international growth of the global air transport sector to identify factors that determine the emergence of transnational companies and different forms of international expansion in the airline industry. An analysis of the market structure is conducted to understand why traditional, full service airlines have adopted alliances and code sharing to internationalise their business, while low-cost carriers prefer more direct methods to enter new foreign markets. [Copyright &y& Elsevier]

Angiolymphoid hyperplasia with eosinophilia (ALHE) is a rare vascular proliferative disorder, which most commonly involves the skin of the head and neck regions. Noncutaneous localization of this pathology is unusual, and its primary localization in large arteries presenting as a pulsatile mass is extremely rare. We report here two cases of ALHE manifested as masses of the occipital and brachial artery. ALHE should be considered in the differential diagnosis of localized peripheral arterial masses in young patients. [Copyright &y& Elsevier]

The protozoan parasite Trypanosoma brucei causes human African sleeping sickness in sub-Saharan Africa. The parasite makes several essential glycoproteins, which has led to the investigation of the sugar nucleotides and glycosyltransferases required to synthesize these structures. Fucose is a common sugar in glycoconjugates from many organisms; however, the sugar nucleotide donor GDP-fucose was only recently detected in T. brucei, and the importance of fucose metabolism in this organism is not known. In this paper, we identified the genes encoding functional GDP-fucose biosynthesis enzymes in T. brucei and created conditional null mutants of TbGMD, the gene encoding the first enzyme in the pathway from GDP-mannose to GDP-fucose, in both bloodstream form and procyclic form parasites. Under nonpermissive conditions, both life cycle forms of the parasite became depleted in GDP-fucose and suffered growth arrest, demonstrating that fucose metabolism is essential to both life cycle stages. In procyclic form parasites, flagellar detachment from the cell body was also observed under nonpermissive conditions, suggesting that fucose plays a significant role in flagellar adhesion. Fluorescence microscopy of epitope-tagged TbGMD revealed that this enzyme is localized in glycosomes, despite the absence of PTS-1 or PTS-2 target sequences. [ABSTRACT FROM AUTHOR]

Abstract: Floating point arithmetic is a subject all too often ignored, yet, for agent-based models in particular, it has the potential to create misleading results, and even to influence emergent outcomes of the model. Using a simple demonstration model, this paper illustrates the problems that accumulated floating point errors can cause, and compares a number of techniques that might be used to address them. We show that inexact representation of parameter values, imprecision in calculation results, and differing implementations of mathematical expressions can significantly influence the behaviour of the model, and create issues for replicating results, though they do not necessarily do so. None of the techniques offer a failsafe approach that can be applied in any situation, though interval arithmetic is the most promising. [Copyright &y& Elsevier]

The core lipopolysaccharide (LPS) of Klebsiella pneumoniae is characterized by the presence of disaccharide αGlcN-(1,4)-αGalA attached by an α1,3 linkage to L-glycero-D-manno-heptopyranose II (LD-HeppII). Previously it has been shown that the WabH enzyme catalyzes the incorporation of GlcNAc from UDP-GlcNAc to outer core LPS. The presence of GlcNAc instead of GlcN and the lack of UDP-GlcN in bacteria indicate that an additional enzymatic step is required. In this work we identified a new gene (wabN) in the K. pneumoniae core LPS biosynthetic cluster. Chemical and structural analysis of K. pneumoniae non-polar wabN mutants showed truncated core LPS with GlcNAc instead of GlcN. In vitro assays using LPS truncated at the level of D-galacturonic acid (GalA) and cell-free extract containing WabH and WabN together led to the incorporation of GlcN, whereas none of them alone were able to do it. This result suggests that the later enzyme (WabN) catalyzes the deacetylation of the core LPS containing the GlcNAc residue. Thus, the incorporation of the GlcN residue to core LPS in K. pneumoniae requires two distinct enzymatic steps. WabN homologues are found in Serratia marcescens and some Proteus strains that show the same disaccharide αGlcN-(1,4)-αGalA attached by an α1,3 linkage to LD-HeppII. [ABSTRACT FROM AUTHOR]

Conservative hemodynamic surgery for varicose veins is a minimally invasive, nonablative technique that preserves the saphenous vein and helps avoid excision of varicosities. It represents a physiologic approach to the surgical treatment of varicose veins based on knowledge of the underlying venous pathophysiology gained through detailed duplex scanning. A change in venous hemodynamics is attained through fragmentation of the blood column by interruption of the refluxing saphenous trunks, closure of the origin of the refluxing varicose branches, and preservation of the communicating veins that drain the incompetent varicose veins into the deep venous system. After surgery, varicose veins regress through a reduction in hydrostatic pressure and efficient emptying of the superficial system by the musculo-venous pump. Obvious advantages of this technique are that it is done in an ambulatory setting, minimizes the risk of surgical complications, and permits a rapid return to full activity. The long-term hemodynamic improvement and recurrence rate of this technique remain to be established. [Copyright &y& Elsevier]

Summary: The protective effect of human gamma globulins on Mycobacterium tuberculosis infection was evaluated in a mouse model of intratracheal infection. Animals receiving human gamma globulins intranasally, 2h before intratracheal challenge showed a significant decrease in lung bacilli load compared to non-treated animals in different time intervals of up to 2 months after challenge. The same effect was obtained when M. tuberculosis was pre-incubated with the gamma globulin before challenge. The protective effect of the gamma-globulin formulation was abolished after pre-incubation with M. tuberculosis. These results suggest a potential role of specific antibodies in the defence against mycobacterial infections. [Copyright &y& Elsevier]

Highlights: [•] Stability of sample and term configurations from CATA was studied using bootstrapping. [•] The number of consumers necessary to yield stable configurations was determined. [•] Stability was affected by degree of difference among samples. [•] 60–80 consumers seems reasonable when working with widely different samples. [•] A configuration stability index is proposed based on a posteriori bootstrapping. [ABSTRACT FROM AUTHOR]

Abstract: A method based on Bayes’ rule was used to estimate the number of discriminators in triangle tests performed by consumers. It is assumed that the total population of consumers is constituted by two groups of individuals, fully discriminators and non-discriminators, and that random numbers of persons from each group form the test panel. Individuals are exchangeable within groups but not between groups and only the responses of non-discriminators follow a binomial distribution with p =1/3. Given an observed result from a triangle test, it is used to estimate the most likely number of discriminators and non-discriminators and their confidence limits. [Copyright &y& Elsevier]

The evaluation of immune responses to RTS,S/AS01 has traditionally focused on immunoglobulin (Ig) G antibodies that are only moderately associated with protection. The role of other antibody isotypes that could also contribute to vaccine efficacy remains unclear. Here we investigated whether RTS,S/AS01 E elicits antigen-specific serum IgA antibodies to the vaccine and other malaria antigens, and we explored their association with protection. Ninety-five children (age 5–17 months old at first vaccination) from the RTS,S/AS01 E phase 3 clinical trial who received 3 doses of RTS,S/AS01 E or a comparator vaccine were selected for IgA quantification 1 month post primary immunization. Two sites with different malaria transmission intensities (MTI) and clinical malaria cases and controls, were included. Measurements of IgA against different constructs of the circumsporozoite protein (CSP) vaccine antigen and 16 vaccine-unrelated Plasmodium falciparum antigens were performed using a quantitative suspension array assay. RTS,S vaccination induced a 1.2 to 2-fold increase in levels of serum/plasma IgA antibodies to all CSP constructs, which was not observed upon immunization with a comparator vaccine. The IgA response against 13 out of 16 vaccine-unrelated P. falciparum antigens also increased after vaccination, and levels were higher in recipients of RTS,S than in comparators. IgA levels to malaria antigens before vaccination were more elevated in the high MTI than the low MTI site. No statistically significant association of IgA with protection was found in exploratory analyses. RTS,S/AS01 E induces IgA responses in peripheral blood against CSP vaccine antigens and other P. falciparum vaccine-unrelated antigens, similar to what we previously showed for IgG responses. Collectively, data warrant further investigation of the potential contribution of vaccine-induced IgA responses to efficacy and any possible interplay, either synergistic or antagonistic, with protective IgG, as identifying mediators of protection by RTS,S/AS01 E immunization is necessary for the design of improved second-generation vaccines. Clinical trial registration : ClinicalTrials.gov: NCT008666191. [ABSTRACT FROM AUTHOR]

The bloodstream form of the human pathogen Trypanosoma brucei expresses oligomannose, paucimannose, and complex N-linked glycans, including some exceptionally large poly-N-acetyllactosamine-containing structures. Despite the presence of complex N-glycans in this organism, no homologues of the canonical N-acetylglucosaminyltransferase I or II genes can be found in the T. brucei genome. These genes encode the activities that initiate the elaboration of the Manα1-3 and Manα1-6 arms, respectively, of the conserved trimannosyl-N-acetylchitobiosyl core of N-linked glycans. Previously, we identified a highly divergent T. brucei N-acetylglucosaminyltransferase I (TbGnTI) among a set of putative T. brucei glycosyltransferase genes belonging to the β3-glycosyltransferase superfamily (Damerow, M., Rodrigues, J. A., Wu, D., Güther, M. L., Mehlert, A., and Ferguson, M. A. (2014) J. Biol. Chem. 289, 9328-9339). Here, we demonstrate that TbGT15, another member of the same β3-glycosyltransferase family, encodes an equally divergent N-acetylglucosaminyltransferase II (TbGnTII) activity. In contrast to multicellular organisms, where GnTII activity is essential, TbGnTII null mutants of T. brucei grow in culture and are still infectious to animals. Characterization of the large poly-N-acetyllactosamine containing N-glycans of the TbGnTII null mutants by methylation linkage analysis suggests that, in wild-type parasites, the Manα1-6 arm of the conserved trimannosyl core may carry predominantly linear poly-N-acetyllactosamine chains, whereas the Manα1-3 arm may carry predominantly branched poly-N-acetyllactosamine chains. These results provide further detail on the structure and biosynthesis of complex N-glycans in an important human pathogen and provide a second example of the adaptation by trypanosomes of β3-glycosyltransferase family members to catalyze β1-2 glycosidic linkages. [ABSTRACT FROM AUTHOR]

Summary Objectives We aimed to characterize prognostic factors and outcomes in adenocarcinomas of the salivary glands. Materials and methods Patients were identified and retrospectively reviewed for clinical and pathologic tumor characteristics. Low and high grade adenocarcinoma histologies were separated and analyzed. Treatment regimens and patient-related outcomes were recorded and measured. Results A total of 51 adenocarcinomas of the salivary glands were reviewed. The most common locations of disease were the superficial lobe of the parotid gland, followed by the deep lobe. Five-year overall and disease free survival rates were 43% and 37%. Univariate analysis identified the following as negative prognostic factors: symptoms of a fixed mass or rapid growth, advanced tumor or nodal stage, and perineural or lymphovascular invasion. Facial nerve paralysis was not found to be a significant prognostic variable. Multivariate analysis confirmed the independent negative prognostic importance of the following characteristics: presentation with a fixed mass or rapid growth, diagnosis of adenocarcinoma not otherwise specified, and positive surgical margins. Conclusions Our results identify several important prognostic factors associated with overall survival in adenocarcinoma of the salivary glands. These prognostic variables encompass symptoms on presentation, clinical and pathologic tumor stage characteristics, and treatment-related factors; all of which are important in patient counseling and may provide impetus for determining treatment escalation. [ABSTRACT FROM AUTHOR]

Carbohydrate structures play important roles in many biological processes, including cell adhesion, cell-cell communication, and host-pathogen interactions. Sugar nucleotides are activated forms of sugars used by the cell as donors for most glycosylation reactions. Using a liquid chromatography-tandem mass spectrometry- based method, we identified and quantified the pools of UDP-glucose, UDP-galactose, UDP-N-acetylglucosamine, GDP-mannose, and GDP-fucose in Plasmodium falciparum intraerythrocytic life stages. We assembled these data with the in silico functional reconstruction of the parasite metabolic pathways obtained from the P. falciparum annotated genome, exposing new active biosynthetic routes crucial for further glycosylation reactions. Fucose is a sugar present in glycoconjugates often associated with recognition and adhesion events. Thus, the GDP-fucose precursor is essential in a wide variety of organisms. P. falciparum presents homologues of GDP-mannose 4,6-dehydratase and GDP-L-fucose synthase enzymes that are active in vitro, indicating that most GDP-fucose is formed by a de novo pathway that involves the bioconversion of GDP-mannose. Homologues for enzymes involved in a fucose salvage pathway are apparently absent in the P. falciparum genome. This is in agreement with in vivo metabolic labeling experiments showing that fucose is not significantly incorporated by the parasite. Fluorescence microscopy of epitope-tagged versions of P. falciparum GDP-mannose 4,6-dehydratase and GDP-L-fucose synthase expressed in transgenic 3D7 parasites shows that these enzymes localize in the cytoplasm of P. falciparum during the intraerythrocytic developmental cycle. Although the function of fucose in the parasite is not known, the presence of GDP-fucose suggests that the metabolite may be used for further fucosylation reactions. [ABSTRACT FROM AUTHOR]

ABC50 is an ATP-binding cassette (ABC) protein, which, unlike most ABC proteins, does not possess membrane-spanning domains. ABC50 interacts with eukaryotic initiation factor 2 (eIF2), which plays a key role in translation initiation and its control. ABC50 binds to ribosomes, and this interaction requires both the N-terminal domain and at least one ABC domain. Knockdown of ABC50 by RNA interference impaired translation of both cap-dependent and -independent reporters, consistent with a positive role for ABC50 in the function of eIF2, which is required for both types of translation initiation. Mutation of the Walker box A or B motifs in both ABC regions of ABC 50 yielded a mutant protein that exerted a dominant-interfering phenotype with respect to protein synthesis and translation initiation. Importantly, although dominant-interfering mutants of ABC50 impaired cap-dependent translation, translation driven by certain internal ribosome entry segments was not inhibited. ABC50 is located in the cytoplasm and nucleoplasm but not in the nucleolus. Thus, ABC50 is not likely to be directly involved in early ribosomal biogenesis, unlike some other ABC proteins. Taken together, the present data show that ABC50 plays a key role in translation initiation and has functions that are distinct from those of other non-membrane ABC proteins. [ABSTRACT FROM AUTHOR]