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2.
Communication Methods and Measures ; 17(2):150-184, 2023.
Article Dans Anglais | ProQuest Central | ID: covidwho-2326884

Résumé

Supervised machine learning (SML) provides us with tools to efficiently scrutinize large corpora of communication texts. Yet, setting up such a tool involves plenty of decisions starting with the data needed for training, the selection of an algorithm, and the details of model training. We aim at establishing a firm link between communication research tasks and the corresponding state-of-the-art in natural language processing research by systematically comparing the performance of different automatic text analysis approaches. We do this for a challenging task – stance detection of opinions on policy measures to tackle the COVID-19 pandemic in Germany voiced on Twitter. Our results add evidence that pre-trained language models such as BERT outperform feature-based and other neural network approaches. Yet, the gains one can achieve differ greatly depending on the specific merits of pre-training (i.e., use of different language models). Adding to the robustness of our conclusions, we run a generalizability check with a different use case in terms of language and topic. Additionally, we illustrate how the amount and quality of training data affect model performance pointing to potential compensation effects. Based on our results, we derive important practical recommendations for setting up such SML tools to study communication texts.

3.
Lancet ; 401(10375): 458-469, 2023 02 11.
Article Dans Anglais | MEDLINE | ID: covidwho-2250667

Résumé

BACKGROUND: Guidelines recommend effective on-demand therapy for all individuals with hereditary angioedema. We aimed to assess the novel oral plasma kallikrein inhibitor, sebetralstat, which is in development, for on-demand treatment of hereditary angioedema attacks. METHODS: In this two-part phase 2 trial, individuals with type 1 or 2 hereditary angioedema aged 18 years or older were recruited from 25 sites, consisting of specialty outpatient centres, across nine countries in Europe and the USA. Individuals were eligible if they had experienced at least three hereditary angioedema attacks in the past 93 days, were not on prophylactic therapy, and had access to and the ability to self-administer conventional attack treatment. In part 1 of the trial, participants were given a single 600 mg open-label oral dose of sebetralstat to assess safety, pharmacokinetics, and pharmacodynamics of the dose. Part 2 was a randomised, double-blind, placebo-controlled, two-sequence, two-period (2 × 2) crossover trial; participants were randomly assigned (1:1) to either sequence 1, in which they were given a single dose of 600 mg of sebetralstat to treat the first eligible attack and a second dose of placebo to treat the second eligible attack, or sequence 2, in which they were given placebo to treat the first eligible attack and then 600 mg of sebetralstat to treat the second eligible attack. Participants and investigators were masked to treatment assignment. The primary endpoint was time to use of conventional attack treatment within 12 h of study drug administration, which was assessed in all participants who were randomly assigned to treatment and who received study drug for two attacks during part 2 of the study. Safety was assessed in all participants who received at least one dose of study drug, starting in part 1. This study is registered with ClinicalTrials.gov, NCT04208412, and is completed. FINDINGS: Between July 2, 2019, and Dec 8, 2020, 84 individuals were screened and 68 were enrolled in part 1 and received sebetralstat (mean age 38·3 years [SD 13·2], 37 [54%] were female, 31 [46%] were male, 68 [100%] were White). 42 (62%) of 68 participants completed pharmacokinetic assessments. Sebetralstat was rapidly absorbed, with a geometric mean plasma concentration of 501 ng/mL at 15 min. In a subset of participants (n=6), plasma samples obtained from 15 min to 4 h after study drug administration had near-complete protection from ex vivo stimulated generation of plasma kallikrein and cleavage of high-molecular-weight kininogen. In part 2, all 68 participants were randomly assigned to sequence 1 (n=34) or sequence 2 (n=34). 53 (78%) of 68 participants treated two attacks (25 [74%] in the sequence 1 group and 28 [82%] in the sequence 2 group). Time to use of conventional treatment within 12 h of study drug administration was significantly longer with sebetralstat versus placebo (at quartile 1: >12 h [95% CI 9·6 to >12] vs 8·0 h [3·8 to >12]; p=0·0010). There were no serious adverse events or adverse event-related discontinuations. INTERPRETATION: Oral administration of sebetralstat was well tolerated and led to rapid suppression of plasma kallikrein activity, resulting in increased time to use of conventional attack treatment and faster symptom relief versus placebo. Based on these results, a phase 3 trial to evaluate the efficacy and safety of two dose levels of sebetralstat in adolescent and adult participants with hereditary angioedema has been initiated (NCT05259917). FUNDING: KalVista Pharmaceuticals.


Sujets)
Angio-oedèmes héréditaires , Kallicréine plasmatique , Adulte , Femelle , Humains , Mâle , Angio-oedèmes héréditaires/traitement médicamenteux , Angio-oedèmes héréditaires/prévention et contrôle , Études croisées , Méthode en double aveugle , Kallicréine plasmatique/antagonistes et inhibiteurs , Résultat thérapeutique , Adulte d'âge moyen
4.
J Allergy Clin Immunol Pract ; 10(10): 2734-2741.e7, 2022 10.
Article Dans Anglais | MEDLINE | ID: covidwho-2049379

Résumé

BACKGROUND: Urticarial vasculitis (UV) is a rare and difficult-to-treat chronic skin disease defined by long-lasting urticarial lesions and the histopathologic finding of leukocytoclastic vasculitis. As of yet, little is known about UV patients' perspective on the disease. OBJECTIVE: To assess UV patients' perspective on the clinical course, treatment response, greatest challenges, and quality-of-life (QOL) impairment. METHODS: A web-based questionnaire was disseminated in a Facebook group of patients with UV. Patients with UV confirmed by skin biopsy were included. RESULTS: Patients with UV had a mean age of 47.3 ± 12.3 years and were mostly female (94.3%; n = 82 of 87). The median delay in diagnosis was 8.1 months (interquartile range, 2.0-46.3). Normocomplementemia and hypocomplementemia were present in 54.0% (n = 27) and 46.0% (n = 23) of 50 patients, respectively. Most patients with UV (51.8%; n = 43 of 83) reported severely decreased QOL due to their disease. Low QOL was also the most frequently reported greatest challenge for patients with UV (40.7%), followed by the long-standing course of UV with frequent relapses (14.8%). Low QOL correlated with long disease duration (r = 0.298; P = .02) and high numbers of clinical symptoms (r = 0.294; P = .007). Patients with UV with allergies, lung diseases, and chronic infections reported lower QOL. Patients with UV with low QOL were treated with analgesics, dapsone, montelukast, omalizumab, and colchicine more often than patients with UV with higher QOL (P < .05 for all). CONCLUSIONS: Our results show a considerable impairment in QOL in patients with UV associated with long disease duration, high symptom burden, and a high need for therapy. Improvement of the management of UV by further research is necessary.


Sujets)
Urticaire , Vascularite leucocytoclasique cutanée , Adulte , Colchicine , Dapsone/usage thérapeutique , Femelle , Humains , Mâle , Adulte d'âge moyen , Omalizumab/usage thérapeutique , Mesures des résultats rapportés par les patients , Qualité de vie , Urticaire/diagnostic , Urticaire/traitement médicamenteux , Vascularite leucocytoclasique cutanée/diagnostic
5.
Nature ; 600(7888): 295-301, 2021 12.
Article Dans Anglais | MEDLINE | ID: covidwho-1626235

Résumé

SARS-CoV-2 is a single-stranded RNA virus that causes COVID-19. Given its acute and often self-limiting course, it is likely that components of the innate immune system play a central part in controlling virus replication and determining clinical outcome. Natural killer (NK) cells are innate lymphocytes with notable activity against a broad range of viruses, including RNA viruses1,2. NK cell function may be altered during COVID-19 despite increased representation of NK cells with an activated and adaptive phenotype3,4. Here we show that a decline in viral load in COVID-19 correlates with NK cell status and that NK cells can control SARS-CoV-2 replication by recognizing infected target cells. In severe COVID-19, NK cells show defects in virus control, cytokine production and cell-mediated cytotoxicity despite high expression of cytotoxic effector molecules. Single-cell RNA sequencing of NK cells over the time course of the COVID-19 disease spectrum reveals a distinct gene expression signature. Transcriptional networks of interferon-driven NK cell activation are superimposed by a dominant transforming growth factor-ß (TGFß) response signature, with reduced expression of genes related to cell-cell adhesion, granule exocytosis and cell-mediated cytotoxicity. In severe COVID-19, serum levels of TGFß peak during the first two weeks of infection, and serum obtained from these patients severely inhibits NK cell function in a TGFß-dependent manner. Our data reveal that an untimely production of TGFß is a hallmark of severe COVID-19 and may inhibit NK cell function and early control of the virus.


Sujets)
COVID-19/immunologie , Cellules tueuses naturelles/immunologie , SARS-CoV-2/immunologie , Facteur de croissance transformant bêta/immunologie , Atlas comme sujet , Régulation de l'expression des gènes/immunologie , Humains , Immunité innée , Grippe humaine/immunologie , Cellules tueuses naturelles/anatomopathologie , RNA-Seq , Analyse sur cellule unique , Facteurs temps , Facteur de croissance transformant bêta/sang , Charge virale/immunologie , Réplication virale/immunologie
6.
Front Immunol ; 12: 722406, 2021.
Article Dans Anglais | MEDLINE | ID: covidwho-1497073

Résumé

Introduction: The COVID-19 pandemic dramatically disrupts health care for patients with chronic diseases including chronic spontaneous urticaria (CSU). As of now, it is unknown if the effects of the pandemic in CSU are different than in other chronic diseases. We also do not know, if different groups of CSU patients, for example female and male patients, are affected differently. Aim: To understand how CSU patients and subgroups are affected by the COVID-19 pandemic in their disease activity and control and treatment, using psoriasis as control. Patients and Methods: We analyzed 399 patients (450 visits) with CSU or psoriasis assessed during August 2019, i.e. before the pandemic, or August 2020, i.e. during the pandemic, for changes in disease activity, disease control, and the treatment they used, and how these changes are linked to age, gender, and disease duration. Results: Male but not female patients with CSU had markedly increased disease activity during the pandemic. CSU patients' age or disease duration were not linked to changes. Male and female patients with psoriasis showed similar increases in disease activity and decreases in disease control. The rate of omalizumab treatment, during the pandemic, was unchanged in male patients and increased in female patients with CSU. The efficacy of omalizumab treatment, during the pandemic, was reduced in male patients but not female patients with CSU. Conclusion: Male but not female CSU patients, during the COVID-19 pandemic, show loss of disease control linked to loss of omalizumab efficacy. The reasons for this need to be investigated.


Sujets)
Urticaire chronique/traitement médicamenteux , Adulte , Antiallergiques/usage thérapeutique , COVID-19/épidémiologie , Femelle , Humains , Mâle , Omalizumab/usage thérapeutique , Pandémies/prévention et contrôle , Résultat thérapeutique
7.
Nat Commun ; 12(1): 1961, 2021 03 30.
Article Dans Anglais | MEDLINE | ID: covidwho-1169399

Résumé

The pathogenesis of severe COVID-19 reflects an inefficient immune reaction to SARS-CoV-2. Here we analyze, at the single cell level, plasmablasts egressed into the blood to study the dynamics of adaptive immune response in COVID-19 patients requiring intensive care. Before seroconversion in response to SARS-CoV-2 spike protein, peripheral plasmablasts display a type 1 interferon-induced gene expression signature; however, following seroconversion, plasmablasts lose this signature, express instead gene signatures induced by IL-21 and TGF-ß, and produce mostly IgG1 and IgA1. In the sustained immune reaction from COVID-19 patients, plasmablasts shift to the expression of IgA2, thereby reflecting an instruction by TGF-ß. Despite their continued presence in the blood, plasmablasts are not found in the lungs of deceased COVID-19 patients, nor does patient IgA2 binds to the dominant antigens of SARS-CoV-2. Our results thus suggest that, in severe COVID-19, SARS-CoV-2 triggers a chronic immune reaction that is instructed by TGF-ß, and is distracted from itself.


Sujets)
Anticorps antiviraux/immunologie , COVID-19/immunologie , SARS-CoV-2/immunologie , Facteur de croissance transformant bêta/immunologie , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , COVID-19/virologie , Femelle , Humains , Immunoglobuline A/immunologie , Immunoglobuline G/immunologie , Interleukines/immunologie , Mâle , Adulte d'âge moyen , Plasmocytes/immunologie , SARS-CoV-2/génétique , Glycoprotéine de spicule des coronavirus/génétique , Glycoprotéine de spicule des coronavirus/immunologie
8.
Allergo J Int ; 30(2): 64-75, 2021.
Article Dans Anglais | MEDLINE | ID: covidwho-1107918

Résumé

BACKGROUND: Chronic urticaria (CU) is a common disease which represents a considerable burden for many patients. The current urticaria guideline describes the evidence-based diagnosis and treatment of CU. In addition, however, questions often arise in everyday practice that are not addressed by the guideline. METHODS: In May 2020, a digital meeting with German urticaria experts was held, in which practical aspects of CU treatment were discussed and supporting aids for everyday clinical treatment formulated. The resulting advice in this document focus on practical questions and the available literature and experiences of the participants. RESULTS: The diagnosis of CU can be made in a short time by means of a thorough anamnesis, a physical examination, and a basic laboratory chemical diagnosis. For this purpose, practical recommendations for everyday practice are given in this paper. An extended diagnosis is only indicated in a few cases and should always be carried out in parallel with an effective therapy. In general, CU should always be treated in the same way, regardless of whether wheals, angioedema or both occur. Symptomatic therapy should be carried out according to the treatment steps recommended by the guidelines. This publication provides practical advice on issues in everyday practice, such as the procedure in the current coronavirus disease 2019 (COVID-19) pandemic, the cardiac risk under higher dosed H1 antihistamines, the self-administration of omalizumab as well as vaccination under omalizumab therapy. In addition to treatment recommendations, topics such as documentation in the practice and family planning with urticaria will be discussed. DISCUSSION: These supporting treatment recommendations serve as an addendum to the current CU guideline and provide support in dealing with CU patients in everyday practice. The aim is to ensure that patients suffering from CU achieve complete freedom of symptoms with the help of an optimal therapy. SUPPLEMENTARY INFORMATION: The online version of this article (10.1007/s40629-021-00162-w) contains supplementary material, which is available to authorized users.

9.
Allergol Select ; 4: 53-68, 2020.
Article Dans Anglais | MEDLINE | ID: covidwho-761024

Résumé

BACKGROUND: Since the beginning of the COVID-19 pandemic, the treatment of patients with allergic and atopy-associated diseases has faced major challenges. Recommendations for "social distancing" and the fear of patients becoming infected during a visit to a medical facility have led to a drastic decrease in personal doctor-patient contacts. This affects both acute care and treatment of the chronically ill. The immune response after SARS-CoV-2 infection is so far only insufficiently understood and could be altered in a favorable or unfavorable way by therapy with monoclonal antibodies. There is currently no evidence for an increased risk of a severe COVID-19 course in allergic patients. Many patients are under ongoing therapy with biologicals that inhibit type 2 immune responses via various mechanisms. There is uncertainty about possible immunological interactions and potential risks of these biologicals in the case of an infection with SARS-CoV-2. MATERIALS AND METHODS: A selective literature search was carried out in PubMed, Livivo, and the internet to cover the past 10 years (May 2010 - April 2020). Additionally, the current German-language publications were analyzed. Based on these data, the present position paper provides recommendations for the biological treatment of patients with allergic and atopy-associated diseases during the COVID-19 pandemic. RESULTS: In order to maintain in-office consultation services, a safe treatment environment must be created that is adapted to the pandemic situation. To date, there is a lack of reliable study data on the care for patients with complex respiratory, atopic, and allergic diseases in times of an imminent infection risk from SARS-CoV-2. Type-2-dominant immune reactions, as they are frequently seen in allergic patients, could influence various phases of COVID-19, e.g., by slowing down the immune reactions. Theoretically, this could have an unfavorable effect in the early phase of a SARS-Cov-2 infection, but also a positive effect during a cytokine storm in the later phase of severe courses. However, since there is currently no evidence for this, all data from patients treated with a biological directed against type 2 immune reactions who develop COVID-19 should be collected in registries, and their disease courses documented in order to be able to provide experience-based instructions in the future. CONCLUSION: The use of biologicals for the treatment of bronchial asthma, atopic dermatitis, chronic rhinosinusitis with nasal polyps, and spontaneous urticaria should be continued as usual in patients without suspected infection or proven SARS-CoV-2 infection. If available, it is recommended to prefer a formulation for self-application and to offer telemedical monitoring. Treatment should aim at the best possible control of difficult-to-control allergic and atopic diseases using adequate rescue and add-on therapy and should avoid the need for systemic glucocorticosteroids. If SARS-CoV-2 infection is proven or reasonably suspected, the therapy should be determined by weighing the benefits and risks individually for the patient in question, and the patient should be involved in the decision-making. It should be kept in mind that the potential effects of biologicals on the immune response in COVID-19 are currently not known. Telemedical offers are particularly desirable for the acute consultation needs of suitable patients.

10.
Allergol Select ; 4: 44-52, 2020.
Article Dans Anglais | MEDLINE | ID: covidwho-613485

Résumé

No abstract available.

11.
Allergo J ; 29(4): 14-27, 2020.
Article Dans Allemand | MEDLINE | ID: covidwho-606497
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