Effects of isoprene on the ozonolysis of Δ3-carene and ß-caryophyllene: Mechanisms of secondary organic aerosol formation and cross-dimerization.

Elucidating the mutual effects between the different volatile organic compounds (VOCs) is crucial for comprehending the formation mechanism of atmospheric secondary organic aerosols (SOA). Here, the mixed VOCs experiments of isoprene and Δ3-carene/ß-caryophyllene were carried out in the presence of O3 using an indoor smog chamber. The suppression effect of isoprene was recognized by the scanning mobility particle sizer spectrometer, online vacuum ultraviolet free electron laser (VUV-FEL) photoionization aerosol mass spectrometry, and quantum chemical calculations. The results indicate that the suppression effect of isoprene on the ozonolysis of Δ3-carene and ß-caryophyllene shows fluctuating and monotonous trends, respectively. The carbon content of the precursor could be the main factor for regulating the strength of the suppression effect. Plausible structures and formation mechanisms of several new products generated from the single VOC precursor and VOC-cross-reaction are proposed, which enrich the category of VOC oxidation products. Meanwhile, a new dimerization mechanism of the RO2 + R'O2 reaction is suggested, which offers an intriguing perspective on the gas phase formation process of particle phase accretion products. The present findings provide valuable insights into clarifying the pivotal roles played by isoprene in the interplay between different VOCs and understanding of SOA formation mechanisms of VOC mixtures, especially nearby the emission origins.

Comprehensive review of pollen-food allergy syndrome: Pathogenesis, epidemiology, and treatment approaches.

Pollen-food allergy syndrome (PFAS) is caused by cross-reaction of a specific pollen antigen with the corresponding food allergen in sensitized individuals. The manifestations are usually limited to oral symptoms; however, sometimes, rhinitis, respiratory and skin symptoms, and anaphylactic shock may occur. In PFAS pathogenesis, when food containing protein antigens (pan-allergens) with high homology to pollen antigens is ingested, mast cells bound to pollen antigen-specific IgE distributed in the oral mucosa cross-react with the food antigen, causing a local type I allergic reaction. The prevalence of PFAS depends on the geographic conditions, such as the type and amount of pollen in the area. PFAS is prevalent in all regions owing to the wide variety of pollen antigens implicated in the disease, such as alder and grass pollen, even outside of the birch habitat area. Basic research on PFAS is expected to significantly contribute to elucidating the pathogenesis and development of therapeutic strategies for PFAS. Currently, effective treatment for patients with PFAS that allows safe consumption of raw foods is lacking, and avoiding the intake of causative foods is the basis of prevention. Furthermore, allergen immunotherapy for PFAS has not yet been established, but various attempts are underway to develop it into a novel treatment strategy. This review highlights the current research landscape on the pathophysiology, epidemiology, and clinical aspects of PFAS. We outline the research gaps that should be addressed to improve the outcomes of patients with PFAS.

Secondary Organic Aerosol from OH-Initiated Oxidation of Mixtures of d-Limonene and ß-Myrcene.

The chemical composition and physical properties of secondary organic aerosol (SOA) generated through OH-initiated oxidation of mixtures containing ß-myrcene, an acyclic monoterpene, and d-limonene, a cyclic monoterpene, were investigated to assess the extent of the chemical interactions between their oxidation products. The SOA samples were prepared in an environmental smog chamber, and their composition was analyzed offline using ultraperformance liquid chromatography coupled with electrospray ionization high-resolution mass spectrometry (UPLC-ESI-HRMS). Our results suggested that SOA containing ß-myrcene showed a higher proportion of oligomeric compounds with low volatility compared to that of SOA from d-limonene. The formula distribution and signal intensities of the mixed SOA could be accurately predicted by a linear combination of the mass spectra of the SOA from individual precursors. Effects of cross-reactions were observed in the distribution of isomeric oxidation products within the mixed SOA, as made evident by chromatographic analysis. On the whole, ß-myrcene and d-limonene appear to undergo oxidation by OH largely independently from each other, with only subtle effects from cross-reactions influencing the yields of specific oxidation products.

Identification of sepsis-causing bacteria from whole blood without culture using primers with no cross-reactivity to human DNA.

Sepsis is a major health concern globally, and identification of the causative organism usually takes several days. Furthermore, molecular amplification using whole blood from patients with sepsis remains challenging because of primer cross-reactivity with human DNA, which can delay appropriate clinical intervention. To address these concerns, we designed primers that could reduce cross-reactivity. By evaluating these primers against human DNA, we confirmed that the cross-reactivity observed with conventional primers was notably absent. In silico PCR further demonstrated the specificity and efficiency of the designed primers across 23 bacterial species that are often associated with sepsis. When tested using blood samples from sepsis patients, the designed primers showed moderate sensitivity and high specificity. Surprisingly, our method identified bacteria even in samples that were detected at other sites but tested negative using conventional blood culture methods. Although we identified some challenges, such as contamination with Acetobacter aceti due to the saponin pretreatment of samples, the developed method demonstrates remarkable potential for rapid identification of the causative organisms of sepsis and provides a new avenue for diagnosis in clinical practice.

Hybrid response to SARS-CoV-2 and Neisseria meningitidis C after an OMV-adjuvanted immunization in mice and their offspring.

COVID-19, caused by SARS-CoV-2, and meningococcal disease, caused by Neisseria meningitidis, are relevant infectious diseases, preventable through vaccination. Outer membrane vesicles (OMVs), released from Gram-negative bacteria, such as N. meningitidis, present adjuvant characteristics and may confer protection against meningococcal disease. Here, we evaluated in mice the humoral and cellular immune response to different doses of receptor binding domain (RBD) of SARS-CoV-2 adjuvanted by N. meningitidis C:2a:P1.5 OMVs and aluminum hydroxide, as a combined preparation for these pathogens. The immunization induced IgG antibodies of high avidity for RBD and OMVs, besides IgG that recognized the Omicron BA.2 variant of SARS-CoV-2 with intermediary avidity. Cellular immunity showed IFN-γ and IL-4 secretion in response to RBD and OMV stimuli, demonstrating immunologic memory and a mixed Th1/Th2 response. Offspring presented transferred IgG of similar levels and avidity as their mothers. Humoral immunity did not point to the superiority of any RBD dose, but the group immunized with a lower antigenic dose (0.5 µg) had the better cellular response. Overall, OMVs enhanced RBD immunogenicity and conferred an immune response directed to N. meningitidis too.

Concordance between two monoclonal antibody-based antigen detection enzyme-linked immunosorbent assays for measuring cysticercal antigen levels in sera from pigs experimentally infected with Taenia solium and Taenia hydatigena.

BACKGROUND: Antigen detection in Taenia solium cysticercosis confirms viable infection in the intermediate host (either pig or human). The reference B158/B60 monoclonal antibody (mAb)-based Ag-enzyme-linked immunosorbent assay (ELISA) has acceptable levels of sensitivity and specificity in human neurocysticercosis with multiple brain cysts, although its sensitivity is lower in cases with single brain cysts, whereas in porcine cysticercosis the assay specificity is affected by its frequent cross-reaction with Taenia hydatigena, another common cestode found in pigs. Our group has produced 21 anti-T. solium mAbs reacting against antigens of the whole cyst, vesicular fluid, and secretory/excretory products, identifying TsW8/TsW5 as the most promising pair of mAbs for an Ag-ELISA. METHODS: We report the use of the TsW8/TsW5 Ag-ELISA to measure cysticercus antigen levels [expressed as optical density (OD) values] in two panels of sera collected from day 0 (baseline) to day 90 postinfection (PI) from pigs experimentally infected with T. solium (n = 26) and T. hydatigena (n = 12). At baseline and on days 28 and 90 PI, we used Bland-Altman (BA) analysis and Lin's concordance correlation coefficients (CCC) to determine the concordance between the TsW8/TsW5 and the B158/B60 Ag-ELISA. RESULTS: The TsW8/TsW5 Ag-ELISA was able to efficiently measure circulating antigen levels in T. solium-infected pigs, similar to that obtained with the B158/B60 Ag-ELISA. Almost all paired log-OD differences between assays were within the limits of agreement (LoA) in the BA analysis at baseline and on days 28 and 90 PI (92.3%, 100%, and 100%, respectively), and a high concordance of log-ODs between assays was also found (Lin's CCC: 0.69, 0.92, and 0.96, respectively, all P < 0.001). In pigs infected with T. hydatigena, almost all paired log-OD differences were within the LoA in the BA analysis, whereas the concordance of log-ODs between assays was low at baseline (Lin's CCC: 0.24) but increased on days 28 and 90 PI (Lins' CCC: 0.88 and 0.98, P < 0.001). CONCLUSIONS/SIGNIFICANCE: The TsW8/TsW5 Ag-ELISA recognizes antigens in pigs with T. solium cysticercosis and is highly concordant with the B158/B60 Ag-ELISA. However, its diagnostic use is hampered by cross-reactions with T. hydatigena, as in other mAb-based Ag-ELISAs.

Antibodies against SARS-CoV-2 non-structural protein 3 cross-react with human muscle cells and neuroglial cells.

Coronavirus Disease 2019 (COVID-19) vaccines protect the public and limit viral spread. However, inactivated viral vaccines use the whole virus particle, which contains many non-capsid proteins that may cause adverse immune responses. A report has found that the ADP-ribose-binding domains of SARS-CoV-2 non-structural protein 3 (NSP3) and human poly(ADP-ribose) polymerase family member 14 (PARP14) share a significant degree of homology. Here, we further show that antibodies against 2019 novel SARS-like coronavirus (SARS-CoV-2) NSP3 can bind human PARP14 protein. However, when G159R + G162R mutations were introduced into NSP3, the antibody titer against human PARP14 decreased 14-fold. Antibodies against SARS-CoV-2 NSP3 can cross-react with human skeletal muscle cells and astrocytes, but not human embryonic kidney 293T cells. However, when G159R + G162R mutations were introduced into NSP3, the cross-reaction was largely inhibited. The results imply that COVID-19 patients with high antibody titers against NSP3 may have high risks of muscular and/or neurological complications. And the possible strategies to improve the safety of inactivated viral vaccines are also discussed.

Cross-reaction mediated by distinct key amino acid combinations in the complementary-determining region (CDR) of a monoclonal antibody.

In immunology, cross-reaction between antigens and antibodies are commonly observed. Prior research has shown that various monoclonal antibodies (mAbs) can recognize a broad spectrum of epitopes related to influenza viruses. However, existing theories on cross-reactions fall short in explaining the phenomena observed. This study explored the interaction characteristics of H1-74 mAb with three peptides: two natural peptides, LVLWGIHHP and LPFQNI, derived from the hemagglutinin (HA) antigen of the H1N1 influenza virus, and one synthetic peptide, WPFQNY. Our findings indicate that the complementarity-determining region (CDR) of H1-74 mAb comprised five antigen-binding sites, containing eight key amino acid residues from the light chain variable region and 16 from the heavy chain variable region. These critical residues formed distinct hydrophobic or hydrophilic clusters and functional groups within the binding sites, facilitating interaction with antigen epitopes through hydrogen bonding, salt bridge formation, and π-π stacking. The study revealed that the formation of the antibody molecule led to the creation of binding groups and small units in the CDR, allowing the antibody to attach to a variety of antigen epitopes through diverse combinations of these small units and functional groups. This unique ability of the antibody to bind with antigen epitopes provides a new molecular basis for explaining the phenomenon of antibody cross-reaction.

[A YOUNG CHILD WITH ALLERGIC SYMPTOMS DUE TO INGESTION OF EDIBLE CRICKETS].

In recent years, the consumption of edible insects has gained attention, and the potential allergic risks associated with their ingestion have been pointed out, though there are limited case reports. A 3-year-old boy exhibited an immediate allergic reaction, showing symptoms of sneezing, nasal discharge, coughing, and eyelid edema after ingesting two cricket crackers. He had previously consumed shrimp but had never eaten edible insects. Given his lack of a history of allergic diseases, the onset of this allergy was unexpected. Subsequent prick tests and oral food challenge tests confirmed that the Two-spotted cricket (Gryllus bimaculatus) was the allergen responsible for his symptoms. The IgE inhibition test indicated that the cricket significantly suppressed the specific IgE levels for moth, shrimp, and mite (Dermatophagoides pteronyssinus). This incident marked the first time in the patient's life that he exhibited allergic symptoms, and it serves as a significant case highlighting the risks of allergies from edible insects. Known allergens in insects include tropomyosin and arginine kinase, which are common in arthropods, but there are reports of other allergens as well, suggesting potential sensitization from cross-reactions. As the consumption of insects becomes more widespread, the number of allergic cases may increase, and food labeling and preventive measures should be considered.

Assessment of Cross-Reactivity of Chimeric Trypanosoma cruzi Antigens with Crithidia sp. LVH-60A: Implications for Accurate Diagnostics.

This study focuses on developing accurate immunoassays for diagnosing Chagas disease (CD), a challenging task due to antigenic similarities between Trypanosoma cruzi and other parasites, leading to cross-reactivity. To address this challenge, chimeric recombinant T. cruzi antigens (IBMP-8.1, IBMP-8.2, IBMP-8.3, and IBMP-8.4) were synthesized to enhance specificity and reduce cross-reactivity in tests. While these antigens showed minimal cross-reactivity with leishmaniasis, their performance with other trypanosomatid infections was unclear. This study aimed to assess the diagnostic potential of these IBMP antigens for detecting CD in patients with Crithidia sp. LVH-60A, a parasite linked to visceral leishmaniasis-like symptoms in Brazil. This study involved seven Crithidia sp. LVH-60A patients and three Leishmania infantum patients. The results indicated that these IBMP antigens displayed 100% sensitivity, with specificity ranging from 87.5% to 100%, and accuracy values between 90% and 100%. No cross-reactivity was observed with Crithidia sp. LVH-60A, and only one L. infantum-positive sample showed limited cross-reactivity with IBMP-8.1. This study suggests that IBMP antigens offer promising diagnostic performance, with minimal cross-reactivity in regions where T. cruzi and other trypanosomatids are prevalent. However, further research with a larger number of Crithidia sp. LVH-60A-positive samples is needed to comprehensively evaluate antigen cross-reactivity.

A murine monoclonal antibody against H5N1 avian influenza virus cross-reacts with human kidney cortex cells.

To investigate the biological characteristics of monoclonal antibodies (mAbs) against avian influenza virus (AIV) and the possible mechanism of AIV-related kidney injury. BALB/c mice were immunized with inactivated H5N1 AIV to prepare monoclonal antibody H5-32, and its subtype, titer and cross-reactivity with other influenza viruses were identified. The reactivity of monoclonal antibody with normal human tissue was analyzed by immunohistochemistry. Immunofluorescence and confocal laser scanning technique were used to detect the binding sites between mAb and human renal cortical cells, and Western blotting was used to detect the size of binding fragments. Immunohistochemical analysis confirmed that monoclonal antibody H5-32 cross-reacted with normal human kidney tissue. In human kidney, mAb H5-32 was localized in the cytoplasm of human renal tubular epithelial cells, and its binding fragment size was about 43 kDa. H5N1 AIV appears to bind to human renal tubular epithelial cells, which may be one of the mechanisms of kidney injury caused by AIV infection.

Factors and co-factors influencing clinical manifestations in nsLTPs allergy: between the good and the bad.

Non-specific lipid transfer proteins (nsLTPs) are a family of plant pan-allergens that represent the primary cause of food allergies in the Mediterranean area, characterized by a wide range of clinical manifestations, ranging from the total absence of symptoms up to anaphylaxis. This wide variety of symptoms is related to the intrinsic capacity of nsLTPs to cause an allergic reaction in a specific subject, but also to the presence of co-factors exacerbating (i.e., exercise, NSAIDs, PPIs, alcohol, cannabis, prolonged fasting, menstruation, acute infections, sleep deprivation, chronic urticaria) or protecting from (i.e., co-sensitization to PR10, profilin or polcalcin) severe reactions. In this picture, recognizing some nsLTPs-related peculiarities (i.e., route, type and number of sensitizations, concentration of the allergen, cross-reactions) and eventual co-factors may help the allergist to define the risk profile of the single patient, in order to promote the appropriate management of the allergy from dietary advices up to the prescription of life-saving epinephrine autoinjector.

Re-Evaluation of the Cross-Reactions of the Antibody against the Causative Agent for Paracoccidioidomycosis Ceti; Paracoccidioides ceti and the Related Fungal Species.

Paracoccidioidomycosis ceti (PCM-C) is a chronic granulomatous keloidal dermatitis in cetaceans that has been reported worldwide and is caused by Paracoccidioides ceti. Serological cross-reactions among highly pathogenic fungal infections and related diseases have been reported. However, the true cross-reaction of antibodies against P. ceti has remained unknown due to the use of positive control sera from infected dolphins. This study aimed to re-evaluate antibodies from mechanically dislodged fungal cells in the infected tissue of a PCM-C case and demonstrate the actual cross-reaction. The results revealed a limited cross-reaction between PCM-C and paracoccidioidomycosis, while the antibodies did not react with other pathogens such as Coccidioides posadasii, Histoplasama capsulatum, and Arthrographis kalrae. Thus, the method for evaluation of the antibody against PCM-C is reliable, and there is potential for epidemiological study.

Immunochemical Characterization of Salix alba (S. alba) Pollen Allergens and Evaluation of the Cross-Reactivity Pattern with Common Allergenic Pollen Grains.

BACKGROUND: Pollens, particularly tree and plant pollens, are one of the major causes of allergic respiratory diseases worldwide. Allergy to pollens of different species of Salix trees has been reported in various regions of the world. The most common type of Salix tree in Iran is white willow (Salix alba). OBJECTIVES: This study aimed to identify and determine the immunochemical characteristics of allergenic proteins in S. alba tree pollen extract using SDS-PAGE and IgE- immunoblotting methods. Moreover, the cross-reaction pattern of the specific IgE antibody of S. alba tree pollen proteins with pollen allergens of common allergenic trees, i.e., Populus nigra (P. nigra), Cupressus sempervirens (C. sempervirens), Pinus brutia (P. brutia) and Platanus orientalis (P. orientalis) in the region was investigated. METHODS: The reaction of allergenic proteins in S. alba pollen extract with specific IgE antibodies in patients' sera was investigated using SDS-PAGE and IgE-immunoblotting methods. The cross-reaction of specific IgE antibodies of the proteins present in S. alba pollen extract with pollen allergens of common allergenic trees in the region was investigated using ELISA and immunoblotting inhibition methods. In silico methods such as phylogenetic tree drawing and alignment of amino acid sequences were used to examine the evolutionary relationship and homology structure of common allergenic proteins (Panallergens) responsible for cross reactions. RESULTS: More than 11 protein bands binding to specific IgE antibodies in patients' sera with a molecular weight between 13 and 95 kDa were identified in the S. alba tree pollen extract. ELISA and immunoblotting inhibition results showed that P. nigra extract could inhibit the binding of IgE antibodies to S. alba pollen extract proteins to a greater extent than C. sempervirens, P. brutia, and P. orientalis tree extracts. In silico methods investigated the results of ELISA and immunoblotting inhibition methods. Moreover, a high structural homology and evolutionary relationship were observed between S. alba and P. nigra tree pollen panallergens. CONCLUSION: In this study, it was found that more than 80 % of the sensitive patients who were examined had specific IgE antibodies reacting with the approximately a 15 kDa-protein present in the S. alba pollen extract. Furthermore, the specific IgE-binding proteins found in the pollens of S. alba and P. nigra trees had relative structural homology, and it is likely that if recombinant forms are produced, they can be used for diagnostic and therapeutic purposes for both of the trees.

Babesia ovis secreted antigen-1 is a diagnostic marker during the active Babesia ovis infections in sheep.

Ovine babesiosis caused by Babesia ovis is an economically significant disease. Recently, a few B. ovis-specific proteins, including recombinant B. ovis secreted antigen-1 (rBoSA1), have been identified. Immunological analyses revealed that rBoSA1 resides within the cytoplasm of infected erythrocytes and exhibits robust antigenic properties for detecting anti-B. ovis antibodies. This protein is released into the bloodstream during the parasite's development. It would be possible to diagnose active infections by detecting this secretory protein. For this purpose, a rBoSA1-specific polyclonal antibody-based sandwich ELISA was optimized in this study. Blood samples taken from the naturally (n: 100) and experimentally (n: 15) infected sheep were analyzed for the presence of native BoSA1. The results showed that native BoSA1 was detectable in 98% of naturally infected animals. There was a positive correlation between parasitemia level in microscopy and protein density in sandwich ELISA. Experimentally infected animals showed positive reactions from the first or second day of inoculations. However, experimental infections carried out by Rhipicephalus bursa ticks revealed the native BoSA1 was detectable from the 7th day of tick attachment when the parasite began to be seen microscopically. Sandwich ELISA was sensitive enough to detect rBoSA1 protein at a 1.52 ng/ml concentration. Additionally, no serological cross-reactivity was observed between animals infected with various piroplasm species, including Babesia bovis, B. bigemina, B. caballi, B. canis, B. gibsoni, Theileria equi, and T. annulata. Taken collectively, the findings show that the rBoSA1-specific polyclonal antibody-based sandwich ELISA can be successfully used to diagnose clinical B. ovis infections in sheep at the early stage.

Blue Wheals and Blue Angioedema Induced by Blue Dyes: A Systematic Review.

BACKGROUND: Blue wheals and blue angioedema, the adverse reactions to blue dye injections with or without anaphylaxis, are poorly defined. OBJECTIVE: The objective is to review the characteristics (ie, sex and age at onset, interval between blue dye injection and symptom onset, clinical manifestations, duration of blue wheals or angioedema), natural courses, and treatments of blue dye adverse reactions. METHODS: A review of the articles published through July 2021 was performed per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis recommendations. RESULTS: Across 523 patients (175 studies) with any adverse reactions to blue dye injections, wheals, angioedema, or both occurred in 193 patients (36.9%). Of these 193 patients, 68 patients (35.2%) developed blue wheals or angioedema, 118 (61.1%) had ordinary wheals or angioedema (nonbluish), and 7 had both (3.6%). We reviewed 169 patients with available data (99 with ordinary lesions and 70 with blue lesions). Patent blue violet had the highest rate of inducing blue wheals or angioedema (odds ratio 4.9). Almost half of the patients with blue wheals or angioedema developed systemic symptoms; and of those with systemic symptoms, all except 1 progressed to anaphylaxis. On-demand treatments with antihistamines, corticosteroids, and epinephrine were commonly used and effective. CONCLUSIONS: Using blue dyes can lead to blue wheals or angioedema and systemic reactions. In patients with a history of a severe allergic reaction to a blue dye, repeat administration of a blue dye should be used only after carefully weighing all the risks and benefits.

Delta Variant of Covid-19 and Hearing Loss.

The Coronavirus Disease of 2019 has now become one of the biggest pandemics of all time. Under the influence of ongoing mutations and widespread geographical expansions, several variants have been reported. Among those, the B.1.617.2 variant, most commonly known as the 'Delta variant' of the coronavirus disease - 19, was first reported in the state of Maharashtra of India in December 2020 and have currently been detected in over 43 countries across six continents around the globe. The B.1.617.2 variant of COVID 19 is a more treacherous variant than the alpha variant due to the increased replication leading to higher viral loads and increased transmission with minimal literature reporting about vaccines' efficacy. In patients with the Alpha variant of COVID-19, hearing loss was an infrequent symptom seen, but on the other hand, the Delta variant happens to have a more frequent hearing loss as a symptom. The increased severity could be one of the reasons why hearing loss could be a typically seen symptom with high chances of occurrence of either a thrombosis, cross-reaction, labyrinthitis/neuritis, etc. and thus audiologists and otolaryngologists must be prepared for the post effect of the delta variant to evaluate and rehabilitate the individuals affected with hearing loss. The following article discusses the presence of hearing loss in individuals with delta variant of COVID 19 and the role of audiologists and otolaryngologists in hearing care.

Unravelling Antigenic Cross-Reactions toward the World of Coronaviruses: Extent of the Stability of Shared Epitopes and SARS-CoV-2 Anti-Spike Cross-Neutralizing Antibodies.

The human immune repertoire retains the molecular memory of a very great diversity of target antigens (epitopes) and can recall this upon a second encounter with epitopes against which it has previously been primed. Although genetically diverse, proteins of coronaviruses exhibit sufficient conservation to lead to antigenic cross-reactions. In this review, our goal is to question whether pre-existing immunity against seasonal human coronaviruses (HCoVs) or exposure to animal CoVs has influenced the susceptibility of human populations to SARS-CoV-2 and/or had an impact upon the physiopathological outcome of COVID-19. With the hindsight that we now have regarding COVID-19, we conclude that although antigenic cross-reactions between different coronaviruses exist, cross-reactive antibody levels (titers) do not necessarily reflect on memory B cell frequencies and are not always directed against epitopes which confer cross-protection against SARS-CoV-2. Moreover, the immunological memory of these infections is short-term and occurs in only a small percentage of the population. Thus, in contrast to what might be observed in terms of cross-protection at the level of a single individual recently exposed to circulating coronaviruses, a pre-existing immunity against HCoVs or other CoVs can only have a very minor impact on SARS-CoV-2 circulation at the level of human populations.

[Sensitization characteristics of ragweed pollen in Beijing area].

Objective:To investigate the sensitization characteristics of ragweed pollen in patients with allergic rhinitis（AR） and（or） allergic asthma in Beijing area, and to provide basis for the prevention and treatment of ragweed pollen sensitized population. Methods:Patients with allergic rhinitis and/or asthma from January 2017 to December 2019 in the outpatient department of Allergy Department of Beijing Shijitan Hospital were retrospectively analyzed in this study. Skin prick test（SPT） was performed with ragweed pollen allergen reagents to compare different ages, genders and respiratory diseases allergen distribution, and to observe the sensitization characteristics of its population. All of the analyses were performed using SAS software version 9.4. Results:A total of 9 727 patients were enrolled in the end. The total positive rate of ragweed pollen SPT was 45.50%（4 426/9 727）, the highest positive rate was 65.54% in 13-17 years old group; The positive rate of ragweed pollen SPT was 49.79% in allergic rhinitis combined with asthma patients, followed by 46.46% in allergic rhinitis patients, and the lowest rate was 19.42% in single allergic asthma patients. There were more females than males in both ragweed pollen sensitized and non-ragweed pollen sensitized groups（P<0.05）, and the proportion was higher in 30-39 years old than in other age groups（P<0.05）. Ragweed pollen sensitization was higher than non-ragweed pollen sensitization in the allergic rhinitis group（98.49% vs 94.76%, P<0.05）. Ragweed pollen with other summer and autumn pollen allergens in patients with positive SPT, the top three were Chenopodium pollen, Humulus pollen and Artemisia grandis pollen, with positive rates of 90.42%, 89.63% and 85.40%, respectively. Ragweed combined with other pollen sensitization accounted for 99.57%（4 407/4 426）. Allergic rhinitis was the main disease in patients sensitized with ragweed pollen alone or combined with other pollens, and there was no significant difference between the two groups（94.97% vs 98.50%, P>0.05）. Conclusion:Ragweed pollen is highly sensitized in Beijing area, single ragweed pollen sensitization is rare, often combined with multiple pollen sensitization, and allergic rhinitis is the main disease.

Psychiatric and non-psychiatric drugs causing false-positive amphetamines urine test in psychiatric patients: a pharmacovigilance analysis using FAERS.

INTRODUCTION: Immunoassay urine drug screen (UDS) is frequently used in clinical practice for initial screening process, being generally available, fast, and inexpensive. Exposure to widely prescribed drugs might determine false-positive UDS amphetamines, leading to diagnostic issues, wrong therapeutic choices, impairment of physician-patient relationship, and legal implications. AREAS COVERED: To summarize and comment on a comprehensive list of compounds responsible for UDS false positives for amphetamines, we conducted a literature review on PubMed along with a comparison with Real-World Data from the Food and Drug Administration Adverse Event Reporting System (FAERS) database analysis between 2010 and 2022. Forty-four articles and 125 Individual Case Safety Reports (ICSR) involving false-positive amphetamine UDS in psychiatric patients were retrieved from FAERS. EXPERT OPINION: False-positive results were described in literature for antidepressants, atomoxetine, methylphenidate, and antipsychotics, but also for non-psychiatric drugs of common use, such as labetalol, fenofibrate, and metformin. Immunoassay method is usually responsible for false-positive results, and in most cases, mass spectrometry (MS) does not eventually confirm the UDS positivity. Physicians should be aware of immunoassays' limitations and when turning to a confirmatory test. Any new cross-reaction should be reported to pharmacovigilance activities.