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Background Anti‐SARS‐CoV‐2 S antibodies prevent viral replication. Critically ill COVID‐19 patients show viral material in plasma, associated with a dysregulated host response. If these antibodies influence survival and viral dissemination in ICU‐COVID patients is unknown. Patients/Methods We studied the impact of anti‐SARS‐CoV‐2 S antibodies levels on survival, viral RNA‐load in plasma, and N‐antigenaemia in 92 COVID‐19 patients over ICU admission. Results Frequency of N‐antigenaemia was >2.5‐fold higher in absence of antibodies. Antibodies correlated inversely with viral RNA‐load in plasma, representing a protective factor against mortality (Adjusted HR [CI 95%], p): (S IgM [AUC ≥ 60]: 0.44 [0.22; 0.88], 0.020); (S IgG [AUC ≥ 237]: 0.31 [0.16; 0.61]

BACKGROUND: Fever-7 is a test evaluating host mRNA expression levels of IFI27, JUP, LAX, HK3, TNIP1, GPAA1 and CTSB in blood able to detect viral infections. This test has been validated mostly in hospital settings. Here we have evaluated Fever-7 to identify the presence of respiratory viral infections in a Community Health Center. METHODS: A prospective study was conducted in the "Servicio de Urgencias de Atencion Primaria" in Salamanca, Spain. Patients with clinical signs of respiratory infection and at least one point in the National Early Warning Score were recruited. Fever-7 mRNAs were profiled on a Nanostring nCounter® SPRINT instrument from blood collected upon patient enrolment. Viral diagnosis was performed on nasopharyngeal aspirates (NPAs) using the Biofire-RP2 panel. RESULTS: A respiratory virus was detected in the NPAs of 66 of the 100 patients enrolled. Median National Early Warning Score was 7 in the group with no virus detected and 6.5 in the group with a respiratory viral infection (P > .05). The Fever-7 score yielded an overall AUC of 0.81 to predict a positive viral syndromic test. The optimal operating point for the Fever-7 score yielded a sensitivity of 82% with a specificity of 71%. Multivariate analysis showed that Fever-7 was a robust marker of viral infection independently of age, sex, major comorbidities and disease severity at presentation (OR [CI95%], 3.73 [2.14-6.51], P

Background The presence of SARS‐CoV‐2 RNA in plasma has been linked to disease severity and mortality. We compared RT‐qPCR to droplet digital PCR (ddPCR) to detect SARS‐CoV‐2 RNA in plasma from COVID‐19 patients (mild, moderate, and critical disease). Methods The presence/concentration of SARS‐CoV‐2 RNA in plasma was compared in three groups of COVID‐19 patients (30 outpatients, 30 ward patients and 30 ICU patients) using both RT‐qPCR and ddPCR. Plasma was obtained in the first 24h following admission, and RNA was extracted using eMAG. ddPCR was performed using Bio‐Rad SARS‐CoV‐2 detection kit, and RT‐qPCR was performed using GeneFinder™ COVID‐19 Plus RealAmp Kit. Statistical analysis was performed using Statistical Package for the Social Science. Results SARS‐CoV‐2 RNA was detected, using ddPCR and RT‐qPCR, in 91% and 87% of ICU patients, 27% and 23% of ward patients and 3% and 3% of outpatients. The concordance of the results obtained by both methods was excellent (Cohen's kappa index = 0.953). RT‐qPCR was able to detect 34/36 (94.4%) patients positive for viral RNA in plasma by ddPCR. Viral RNA load was higher in ICU patients compared with the other groups (P 85%). RT‐qPCR was as useful as ddPCR to detect and quantify SARS‐CoV‐2 RNAemia in plasma.

BACKGROUND Following the SEPSIS-3 consensus, detection of organ failure as assessed by the SOFA (Sequential Organ Failure Assessment) score, is mandatory to detect sepsis. Calculating SOFA outside of the Intensive Care Unit (ICU) is challenging. The alternative in this scenario, the quick SOFA, is very specific but less sensible. Biomarkers could help to detect the presence of organ failure secondary to infection either in ICU and non-ICU settings. MATERIALS AND METHODS We evaluated the ability of four biomarkers (C-Reactive protein (CRP), lactate, mid-regional proadrenomedullin (MR-proADM) and procalcitonin (PCT)) to detect each kind of organ failure considered in the SOFA in 213 patients with infection, sepsis or septic shock, by using multivariate regression analysis and calculation of the area under the receiver operating curve (AUROC). RESULTS In the multivariate analysis, MR-proADM was an independent predictor of five different failures (respiratory, coagulation, cardiovascular, neurological and renal). In turn, lactate predicted three (coagulation, cardiovascular and neurological) and PCT two (cardiovascular and renal). CRP did not predict any of the individual components of SOFA. The highest AUROCs were those of MR-proADM and PCT to detect cardiovascular (AUROC, CI95%): MR-proADM (0.82 [0.76-0.88]), PCT (0.81 [0.75-0.87] (P

The extracellular heat shock proteins (eHsp) family act as molecular chaperones regulating folding, transporting protein and are associated with immune modulation in different physiological and pathological processes. They have been localized in different gestational tissues and their concentration in amniotic fluid and serum has been determined. In the present study, we proposed to determine the concentration of eHsp‐60, ‐70, IL‐1β and TNFα in the serum of pregnant patients with 34 weeks of gestation with and without clinical evidences of preeclampsia (PE). Our results indicate significant increase of these markers in patients with PE with respect to healthy pregnant patients without active labor. Finally, the concentration of eHsp‐60 and ‐70 correlated positively with the hepatic dysfunction markers uric acid, lactate dehydrogenase (LDH), glutamic oxaloacetic transaminase (GOT) glutamic pyruvic transaminase (GPT), and inflammatory IL‐1β and TNFα response. In conclusion, our results demonstrate a strong associated between Hsp and marker of hepatic dysfunction.

Naturally occurring lactams, such as the polyketide-derived macrolactams, provide a diverse class of natural products that could enhance existing chemically produced lactams. Although β-amino acid loading in the fluvirucin B2 polyketide pathway was proposed by a previously identified putative biosynthetic gene cluster, biochemical characterization of the complete loading enzymes has not been described. Here we elucidate the complete biosynthetic pathway of the β-amino acid loading pathway in fluvirucin B2 biosynthesis. We demonstrate the promiscuity of the loading pathway to utilize a range of amino acids and further illustrate the ability to introduce non-native acyl transferases to selectively transfer β-amino acids onto a polyketide synthase (PKS) loading platform. The results presented here provide a detailed biochemical description of β-amino acid selection and will further aid in future efforts to develop engineered lactam-producing PKS platforms.

In fungal non-reducing polyketide synthases (NR-PKS), the acyl-carrier protein (ACP) carries the growing polyketide intermediate through iterative rounds of elongation, cyclization and product release. This process occurs through a controlled, yet enigmatic coordination of the ACP with its partner enzymes. The transient nature of ACP interactions with these catalytic domains imposes a major obstacle for investigation of the influence of protein–protein interactions on polyketide product outcome. To further our understanding about how the ACP interacts with the product template (PT) domain that catalyzes polyketide cyclization, we developed the first mechanism-based crosslinkers for NR-PKSs. Through in vitro assays, in silico docking and bioinformatics, ACP residues involved in ACP–PT recognition were identified. We used this information to improve ACP compatibility with non-cognate PT domains, which resulted in the first gain-of-function ACP with improved interactions with its partner enzymes. This advance will aid in future combinatorial biosynthesis of new polyketides.

Objective The impact of endogenous immunoglobulin isotypes on the prognosis of patients with severe sepsis has not been sufficiently explored. The aim of this study was to evaluate the association between immunoglobulin levels in plasma and survival in patients with this condition. Design and patients A prospective multicentre cohort study was conducted. A total of 172 adult patients admitted to the intensive care unit (ICU) with severe sepsis or septic shock were recruited. Patients were classified based on deciles of immunoglobulin concentrations at diagnosis of sepsis. Categorical variables were created and tested for their association with survival during hospitalization in the ICU. Results Overall, 42 patients died in the ICU during the study. Kaplan–Meier analysis showed that immunoglobulin concentrations below 300 mg dL−1 for IgG1, 35 mg dL−1 for IgM and 150 mg dL−1 for IgA were associated with shorter survival times. Multivariate regression analysis showed that IgG1 < 300 mg dL−1 was a risk factor for mortality [odds ratio (OR) 2.50, 95% confidence interval (CI) 1.04–6.03; P = 0.042]. The combined presence of IgG1, IgM and IgA levels below the described thresholds had a synergistic impact on mortality risk (OR 5.27, 95% CI 1.41–19.69; P = 0.013). A similar effect was observed for combined low levels of IgG1 and IgA (OR 4.10, 95% CI 1.28–13.12; P = 0.018) and also of IgG1 and IgM (OR 3.10. 95% CI 1.13–8.49; P = 0.028). Conclusions The combined presence of low levels of the endogenous immunoglobulins IgG1, IgM and IgA in plasma is associated with reduced survival in patients with severe sepsis or septic shock. Assessment of the concentrations of these immunoglobulins could improve the results of treatment with exogenous immunoglobulins in patients with sepsis.

Infective endocarditis is a disease normally of bacterial cause which affects the endocardic tissue, specifically the valves (native or prosthetic). It is a serious illness and mortality rates remain high, ranging between 20% and 40%. Previous reports have evidenced the potential role of cytokines in the diagnosis of this disease, but no information is available on their relationship with outcome. We recruited 26 consecutive patients with late prosthetic valve endocarditis requiring surgical treatment according to Duke criteria. Eight cytokines were measured in plasma in the first 24 h following diagnosis by using a Bio-Rad multiplex assay. Levels of IL-6, IL-8 and interferon gamma (IFN-γ) were higher in non survivors. Receiver operating characteristic curve analysis evidenced that IL-6, IL-8 and IFN-γ behaved as good diagnostic tests for identifying those patients with fatal outcome (area under the curve, CI 95%, p): IL-6: [0.81 (0.61-1.00) 0.012]; IL-8 [0.76 (0.56-0.96) 0.035]; IFN-γ [0.79 (0.59-0.99) 0.021]. Levels of IL-6, IL-8 and IFN-γ correlated positively between them, indicating that they are produced as consequence of a simultaneous response to the infection. Our findings support the participation of IL-6, IL-8 and IFN-γ in the events linked to fatal outcome in infective prosthetic valve endocarditis.

Scope The aims of this study were to evaluate IgE-mediated hypersensitivity to pine nut with details of clinical reactions and to characterize major pine nut allergens. Methods and results The study included ten consecutive teenagers and adults diagnosed with IgE-mediated clinical allergy to pine nut. Two major pine nut allergens were purified and identified and the secondary structures and susceptibility to digestion were characterized. Severe reactions represent 80% of allergic reactions to pine nut in this study. Moreover, 70% of the patients were monosensitized to this nut. Two major allergens with molecular weights of 6 and 50 kDa were purified and identified as albumin and vicilin, respectively. The 6 kDa protein (albumin), rich in α-helix content, was far more stable to peptic and tryptic digestion as compared with 50 kDa protein (vicilin), which was quickly broken down. The secondary structure of the purified 50 kDa protein showed 41% β-sheet, 5% α-helix, and 54% random coil and/or loops. Conclusion Eighty percent of allergic reactions to pine nut in the ten patients included in this study were severe. Most patients (70%) were monosensitized to this nut. Two major allergens with molecular weights of 6 and 50 kDa were purified and identified as albumin and vicilin, respectively.

To cite this article: Matias V, San Feliciano L, Fernandez JE, Lapena S, Garrido E, Ardura J, Soga MJ, Aragon MP, Remesal A, Benito F, Andres J, Centeno F, Marugan V, Bachiller R, Bermejo-Martin JF. Host and environmental factors influencing respiratory secretion of pro-wheezing biomarkers in preterm children. Pediatric Allergy Immunology 2012: 23: 441–447. Abstract Cytokines are actively secreted by the respiratory mucosa of preterm children and participate in the pathogenesis of wheezing. This study aimed to identify the factors that could potentially influence respiratory secretion of cytokines in these children. A nasopharyngeal aspirate (NPA) was collected from 77 preterm children 1 yr after birth. NPAs from 14 healthy, 1-yr-old term children were collected in parallel. 27 cytokines were measured in the NPAs using a multiplex assay. Multivariate stepwise regression analysis with Bonferroni correction evidenced that the variable [daycare attendance] was associated with higher levels of [monocyte chemoattractant protein-1 (MCP-1), IL-6, vascular endothelial growth factor (VEGF), IL-1β, IL-10, tumor necrosis factor (TNF)-α]; [male sex] with higher levels of (MCP-1, VEGF, and IL-1β); [smokers at home] was associated with higher levels of MCP-1 (p

Author(s): Barajas, Jesus F; Zargar, Amin; Pang, Bo; Benites, Veronica T; Gin, Jennifer; Baidoo, Edward EK; Petzold, Christopher J; Hillson, Nathan J; Keasling, Jay D

Background: Chestnut and natural rubber latex (NRL) allergy are often associated in the latex-fruit syndrome. Aim of the study: To establish whether the concurrent NRL and chestnut IgE antibody reactivity are the results of co-sensitization or cross-reactivity. Methods: Sera from 19 patients with chestnut- and NRL-specific IgE were selected and tested for reactivity with recombinant (r) latex allergens. Cross-reactivity was explored by IgE-inhibition experiments using chestnut or NRL allergens as solid phase on ImmunoCAP. Results: IgE-antibodies were detected to rHev b 6.01 (prohevein) in 58% of the sera, to rHev b 5 in 32%, to rHev b 12 in four of 13 sera, to rHev b 7.02 and rHev b 11 in four, and to rHev b 1 in two of 19 sera. rHev b 8-IgE antibodies were found in nine sera (47%), whereas six displayed mono-sensitization to rHev b 8 with regard to our test panel. Three of 16 sera showed IgE to cross-reactive carbohydrate determinants. In most sera recognizing rHev b 5 and/or rHev b 6.01 as major allergens the IgE-reactivity to NRL remained unaffected by chestnut extract and chestnut-IgE remained unaffected by NRL extract. Conversely, in sera with rHev b 8 as dominant allergen IgE-binding to NRL was nearly completely inhibited by chestnut and vice versa. IgE-binding to rHev b 8 was abolished by chestnut extract. Conclusions: Although patients have concomitant IgE antibody reactivity to chestnut and NRL, cross-reactivity could be demonstrated mainly in those patients with IgE to Hev b 8 (profilin) from NRL.

A synthetic strategy has been developed for the preparation of new peripheral amine- or ammonium-terminated carbosilane dendrimers of type nG-[Si(OCH2CH2NMe2)y]x or nG-[Si(OCH2CH2NMe3+I–)y]x, respectively. It consists of the alcoholysis of well-known chlorosilane-terminated dendrimers with N,N-dimethylethanolamine and the subsequent quaternization with MeI. All these systems are susceptible to hydrolysis, although the decomposition depends on concentration and dendrimer generation. Evaluation of dendrimer toxicities by phase-contrast light microscopy and MTT assay were carried out, and evidence of dendrimer/oligonucleotide complex formation was carried out by gel electrophoresis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

While the detrimental consequences of opportunistic tuberculosis (TB) in the course and outcome of HIV‐1 infection are well studied, little information about the impact of the mycobacterial infection on the phenotype of T lymphocytes is available. In this study we analyzed by cytofluorimetry the peripheral blood T cell phenotype of 13 patients with AIDS, 23 HIV‐1 negative patients with active pulmonary TB, nine HIV‐1/Mycobacterium tuberculosis coinfected individuals, and 21 age‐ and sex‐matched healthy controls. CD4+ T cells were equally depleted in AIDS and coinfection (P

Aspergillus fumigatus is responsible for many allergic respiratory diseases, the most notable of which − due to its severity − is allergic bronchopulmonary aspergillosis. Aspf1 is a major allergen of this fungus: this 149-amino acid protein belongs to the ribotoxin family, whose best characterized member is α-sarcin (EC 3.1.27.10). The proteins of this group are cytotoxic ribonucleases that degrade a unique bond in ribosomal RNA impairing protein biosynthesis. Aspf1 and its deletion mutant Aspf1Δ(7–22) have been produced as recombinant proteins; the deleted region corresponds to an exposed β-hairpin. The conformation of these two proteins has been studied by CD and fluorescence spectroscopy. Their enzymatic activity and cytotoxicity against human rhabdomyosarcoma cells was also measured and their allergenic properties have been studied by using 58 individual sera of patients sensitized to Aspergillus. Aspf1Δ(7–22) lacks cytotoxicity and shows a remarkably reduced IgE reactivity. From these studies it can be concluded that the deleted β-hairpin is involved in ribosome recognition and is a significant allergenic region.

According to the recently revised nomenclature for allergy the term "Food Hypersensitivity" is proposed to define a reaction on food exposure causing objectively reproducible symptoms or signs at a dose tolerated by normal subjects. Those reactions to food in which immunologic mechanisms are demonstrated comprise the term "Food Allergy". Immunologic reactions to food in which an immunoglobulin E (IgE)-mediated mechanism is established are defined as IgE-mediated food allergy. This review focuses on IgE-mediated allergic reactions to foods.

This article reviews the history and recent progress in the study of the dynamics of the H+H2O reaction, which has become a benchmark for experimental research in the field of gas-phase reaction dynamics. The dynamics of H+H2O is discussed in terms of the different observable properties: integral cross-sections, rate coefficients, product state distributions, differential cross-sections, and vector correlations. It is shown how experimental measurements and first-principle theoretical calculations have revealed the interesting microscopic aspects of this elementary chemical reaction.

Background Vegetables of the Liliaceae family, such as garlic or onion, have been reported to cause occupational asthma. However, there are few data on adverse reactions to asparagus. We evaluated the role of asparagus as a cause of asthma in a patient with respiratory symptoms occurring at work (horticulture) and studied relevant allergens. Methods A 28-year-oId man complained of rhinoconjunctivitis and asthma when harvesting asparagus at work. Eating cooked asparagus did not provoke symptoms. A positive skin test reaction was observed with raw asparagus, Aiternaria atternata. and grass-pollen extracts. The methacholine test demonstrated mild bronchial hyperresponsiveness. The patient had an immediate asthmatic response after challenge with raw asparagus extract. Bronchial provocation tests with boiled asparagus, A. aiternata. and control extracts were negative. Two unexposed subjects with seasonal allergic asthma did not react to the raw asparagus extract. Results The double-blind, placebo-controlled food challenge with raw asparagus was negative. Serum asparagus-specific IgE was 13.9 kUA/1. By SDS-PAGE immunoblot, at least six IgE-binding components, ranging from 22 to 73 kDa, were detected only in raw asparagus. Concltisions We report a case of occupational asthma caused by asparagus inhalation, confirmed by specific bronchoprovocation. Immunoblot analysis showed that asparagus allergens are very labile and quite sensitive to heat denaturation.

IgE-antibody reactivity to boiled Atlantic shrimp (Pandalus borealis) and German cockroach (Blattella germanica) of sera from 89 patients, sensitive to one or the other, was investigated with an enzymatic immunoassay for specific IgE detection (CAP-FEIA System, Pharmacia, Sweden). IgE serum levels to both antishrimp and anticockroach allergens were found to be positive in 76 of the 89 (85.4%) tested sera. A positive anticockroach IgE was very rare in the absence of detectable antishrimp IgE (five of 89 sera). Linear regression analysis on antishrimp and anti-German cockroach IgE levels-log plot revealed a correlation coefficient (r) of 0.73. Inhibition experiments showed that boiled Atlantic shrimp extract inhibited CAP with German cockroach, and vice versa. Immunoblotting showed the strongest IgE binding for both allergenic extracts between 30 and 43 kDa. By blot inhibition, the binding capacity of German cockroach was totally abolished by Atlantic shrimp extract, while German cockroach extract only partially IgE binding to Atlantic shrimp. Cross-reactivity exists between shrimp, an important food allergen, and German cockroach, which has an increasing role in allergic asthma. It could be important to determine the clinical significance of cross-allergy to both allergens, in which exposures occur in different ways.