Tuberculosis disease in immunocompromised children and adolescents: a pTBnet multi-centre case-control study.

BACKGROUND: In high-resource settings the survival of immunocompromised (IC) children has increased and immunosuppressive therapies are increasingly being used. This study aimed to determine the clinical characteristics, performance of diagnostic tools and outcome of IC children with TB in Europe. METHODS: Multicentre, matched case-control study within the Paediatric Tuberculosis Network European Trials Group (ptbnet), capturing TB cases <18 years diagnosed 2000-2020. RESULTS: 417 TB cases were included, comprising 139 children with IC (HIV, inborn errors of immunity, drug-induced immunosuppression and other immunocompromising conditions) and 278 non-IC children as controls. Non-respiratory TB was more frequent among cases than controls (32.4% vs. 21.2%; p = 0.013). IC patients had an increased likelihood of presenting with severe disease (57.6% vs. 38.5%; p < 0.001; OR [95% CI]: 2.073 [1.37-3.13]). Children with IC had higher rates of false-negative tuberculin skin test (31.9% vs. 6.0%; p < 0.001) and QuantiFERON-TB Gold assay (30.0% vs. 7.3%; p < 0.001) results at diagnosis. Overall, the microbiological confirmation rate was similar in IC and non-IC cases (58.3% vs. 49.3%; p = 0.083). Although the mortality in IC children was <1%, the rate of long-term sequelae was significantly higher than in non-IC cases (14.8% vs. 6.1%; p = 0.004). CONCLUSIONS: IC children with TB disease in Europe have increased rates of non-respiratory TB, severe disease, and long-term sequelae. Immune-based TB tests have poor sensitivity in those children. Future research should focus on developing improved immunological TB tests that perform better in IC patients, and determining the reasons for the increased risk of long-term sequelae, with the aim to design preventive management strategies.

Subjective Smell Disturbances in Children with Sars-Cov-2 or Other Viral Infections do not Correspond with Olfactory Test Results.

BACKGROUND: Olfactory dysfunction associated with SARS-CoV-2 infection in children has not been verified by a validated olfactory test. We aimed to determine whether these complaints are objectifiable (test-based hyposmia), how often they occur during acute SARS-CoV-2 infection compared to other upper respiratory tract infections (URTI), as well as in children recovered from COVID-19 compared to children with long COVID. METHODS: Olfactory testing (U-sniff test; hyposmia<8 points) and survey-based symptom assessments were performed in 434 children (5-17 years; 04/2021-06/2022). 186 symptom-free children served as controls. Of the children with symptoms of acute respiratory tract infection, SARS-CoV-2 PCR test results were positive in 45 and negative in 107 children (URTI group). Additionally, 96 children were recruited at least 4 weeks (17.6±15.2 weeks) after COVID-19, of whom 66 had recovered and 30 had developed long COVID. RESULTS: Compared to controls (2.7%), hyposmia frequency was increased in all other groups (11-17%, p<0.05), but no between-group differences were observed. Only 3/41 children with hyposmia reported complaints, whereas 13/16 children with complaints were normosmic, with the largest proportion being in the long-COVID group (23%, p<0.05). CONCLUSION: Questionnaires are unsuitable for assessing hyposmia frequency in children. Olfactory complaints and hyposmia are not specific for SARS-CoV-2 infection. The number of complaints in the long-COVID group could result from aversive olfactory perception, which is undetectable with the U-sniff test.

The value of biomarkers in the therapy of CRSwNP with biologicals-a long-term follow-up of dupilumab therapy.

PURPOSE: Since its release, Dupilumab has shown great results in treating severe uncontrolled CRSwNP. However, there is a lack of real-world data beyond 12 months of follow-up, and it is not clear to what extent biomarkers are appropriate for monitoring and predicting the Dupilumab therapy success. Hence, this study aims to analyze biomarkers for monitoring therapy, predicting therapy success and assess the effect of Dupilumab in real-world settings. METHODS: The follow-up was performed with 104 patients retrospectively up to 22 months, assessing SNOT-22, NPS, olfactometry, ACS, FEV-1, and blood biomarkers (total serum IgE, Eosinophils, ECP). Patients were divided into subgroups depending on their pretherapeutic biomarker levels and subsequent development was analyzed. RESULTS: There was substantially improvement in all clinical parameters up to 1 year and then continuously up to month 22. Patients with initially elevated baseline blood eosinophil counts (> 0.5 billion/L) had a trend of better SNOT-22 development after 1 year (- 12.19 points, p = 0.03). The course of total serum IgE showed moderate correlation with almost all clinical variables obtained. Therapy was well tolerated with only mild and transient adverse events. CONCLUSION: Dupilumab has considerably reduced symptoms and disease severity even beyond 1 year of treatment, supporting its role as targeted and effective treatment option for CRSwNP. Our data shows that total serum IgE is a promising biomarker for the monitoring during the treatment with Dupilumab. Elevated pre-therapeutic serum eosinophil counts may be a predictor of good subjective response to therapy. Larger cohorts and a long-term-follow-up over years are needed to further consolidate these findings.

[Decision-making in the treatment of chronic rhinosinusitis with nasal polyps in the era of biologics]. / Entscheidungsfindung bei der Behandlung der chronischen Rhinosinusitis mit Nasenpolypen in der Ära der Biologika.

Chronic rhinosinusitis is one of the most common chronic diseases in the population. Chronic rhinosinusitis with nasal polyps (CRSwNP) in adults is predominantly characterized by a type 2 inflammatory endotype. If sufficient control cannot be achieved through primary drug therapy, surgical intervention is usually recommended as the next stage of treatment. Nowadays, various biologics are available that have been or will be approved for use in these patients. This review summarizes the presentations from the 29th Congress of the European Rhinologic Society in Sofia 2023 and the latest findings on decision-making in the treatment of CRSwNP. Standard therapy with medication and sinus surgery fails in some patients with CRSwNP. Biologics that act on the type 2 inflammatory pathway led to a reduction in the nasal polyp score (NPS), an improvement in nasal obstruction, and an improvement in quality of life without significant side effects. Biomarkers such as total IgE, serum eosinophils, and Osteoprotegerin (OPG) can provide indications of the success of the treatment. In summary, it can be said that for many patients with recurrent CRSwNP, a combination of paranasal sinus surgery and treatment with a biologic that is precisely tailored to the patient's endotype is the best option. However, the question of which surgical approach and which biologic at which time and for which patient is still ongoing and requires further studies.

[Fundamentals and practice of the application of nasal packing in sinonasal surgery]. / Grundlagen und Praxis der Anwendung von Nasentamponaden in der endonasalen Chirurgie.

BACKGROUND AND OBJECTIVES: This paper presents an overview on nasal packing materials which are available in Germany. The current literature is analyzed whether there are robust criteria regarding use nasal packing after sinonasal surgery, whether there are fundamental and proven advantages or disadvantages of products, and what this means in clinical practice. MATERIALS AND METHODS: Selective literature analysis using the PubMed database (key words "nasal packing", "nasal tamponade", "nasal surgery", "sinonasal surgery", or "sinus surgery"), corresponding text books and resulting secondary literature. RESULTS AND CONCLUSIONS: Because of systematic methodological shortcomings, the literature does not help in the decision-making about which nasal packing should be used after which kind of sinonasal surgery. In fact, individual approaches for the many different clinical scenarios are recommended. In principle, nasal packing aims in hemostasis, should promote wound healing, and should not result in secondary morbidity. Nasal packing materials should be smooth (non-absorbable materials), inert (absorbable materials), and should not exert excessive pressure. Using non-absorbable packing entails the risk of potentially lethal aspiration and ingestion. For safety reasons inpatient control is recommended as long as this packing is in situ. With other, uncritical packing materials and in patients with special conditions, outpatient control could be justified.

Dupilumab (Dupixent®) tends to be an effective therapy for uncontrolled severe chronic rhinosinusitis with nasal polyps: real data of a single-centered, retrospective single-arm longitudinal study from a university hospital in Germany.

INTRODUCTION: Chronic rhinosinusitis with nasal polyps (CRSwNP) is an inflammatory disease, which is usually type 2-mediated in the western hemisphere, associated with severe therapeutic and socioeconomic challenges. The first targeted systemic treatment option for severe uncontrolled CRSwNP is a human monoclonal antibody against the interleukin-4 receptor α (IL-4Rα) subunit called dupilumab, which was approved for subcutaneous administration in Germany in October 2019. The purpose of this study is to investigate the efficacy of dupilumab in real life in patients treated with dupilumab in label according to license in our department in 2019-2021. MATERIALS AND METHODS: Since October 2019, we have investigated 40 patients (18 men, 22 women) treated with dupilumab in a single-center, retrospective single-arm longitudinal study. The following parameters were collected before treatment (baseline), at 1 month, 4 months, 7 months, 10 months, and 13 months: the Sino-Nasal Outcome Test-22 (SNOT-22), the forced expiratory pressure in 1 s (FEV-1), the olfactometry using Sniffin' Sticks-12 identification test (SSIT), a visual analog scale of the total complaints, the Nasal Polyp Score (NPS), histologic findings as well as total serum IgE, eosinophilic cationic protein in serum and blood eosinophils. RESULTS: The average age was 52.7 years (± 15.3). The follow-up period was 13 months. The SNOT-22 average was 60 points (± 22.2) at the first visit, 28.2 points (± 17.1) after 4 months and 20.8 points (± 17.7) after 13 months. The NPS was 4.3 points (± 1.5), after 4 months 2.1 points (± 1.3) and after 13 months 1.4 points (± 1.1). Olfactometry showed 3.2 points (± 3.7) at the baseline, 7.0 points (± 4.0) after 4 months and 7.8 points (± 3.5) after 13 months. The other parameters also improved. Most parameters showed linear dependence in the slopes under therapy (p < 0.001). Adverse side effects were mostly only mild, and no rescue therapy was needed. CONCLUSION: There is a clear improvement in the medical condition and symptoms in all categories mentioned under therapy with dupilumab, as well as a reduction in the need for systemic glucocorticoids and revision surgery as rescue treatment. Our results show that dupilumab tends to be an effective therapy alternative for severe CRSwNP.

Measuring person-centred care in german nursing homes - exploring the construct validity of the Dementia Policy Questionnaire: a cross-sectional study of a secondary data set.

BACKGROUND: To ensure the sustainable implementation of dementia-specific person-centred care (PCC) in nursing homes, internal policies are crucial. The preliminary German Dementia Policy Questionnaire, which features 19 dichotomous items, assesses the existence of and evaluates these policies. This article reports the results of an exploration of the construct validity of the preliminary Dementia Policy Questionnaire. METHODS: This study is a cross-sectional study that references a secondary data set drawn from a national survey study of a randomized, stratified sample of 134 nursing homes in Germany. To explore the construct validity of the preliminary Dementia Policy Questionnaire, we conducted an adjusted multiple correspondence analysis of the pretested 19-item assessment. We included data assessed using the preliminary Dementia Policy Questionnaire from 134 care units associated with 134 nursing homes; these data were collected via telephone interviews with nursing home administrators or their representatives. RESULTS: Two items assessing visitor regulations and regulations regarding the inclusion of residents in staff selection were less frequent and were therefore excluded from the adjusted multiple correspondence analysis. In total, nine items were assigned to two dimensions. The items assigned to the first dimension assess existing regulations for PCC as well as existing regulations regarding the involvement of the resident, relatives and the multiprofessional team in the collection of information concerning preferences, case conferences or decision making. The items assigned to the second dimension assess existing regulations regarding the systematic assessment of resident preferences and their requirements. CONCLUSION: The study produces exploratory evidence concerning the preliminary Dementia Policy Questionnaire. Since the dimensions of the items included in this questionnaire cannot be conceptualized clearly, the instrument in its current state requires further development.

Dementia specific care structures in nursing homes-Study protocol of a telephone-based survey study in a nationwide random sample.

AIM: To describe a study protocol for a survey study in German nursing homes that (1) plans to enhance a typology of care units (2) and investigates the association between different care unit types and the provision of dementia-specific interventions based on a stratified randomized sample. BACKGROUND: Many nursing homes in Germany provide Dementia Special Care Units. Existing definitions often do no justice to the complexity of their context. In this study, we define context as structural and organizational variables. It is necessary to define an empirical based set of indicators to characterize care units with respect to dementia care. DESIGN: Observational survey study with a cross-sectional design. METHODS: We will use a stratified random nationwide sample of 160 German nursing homes. Stratification variables are federal state and the existence of a Dementia Special Care Unit. The sampling frame from which the participating nursing homes are selected is a list with the total population of German nursing homes (n = 11.658). Data will be gathered on the level of the nursing homes and one of their care units via computer-assisted telephone interviews with a standardized questionnaire. The distribution of the assessed variables (contextual characteristics) will be described in absolute and relative frequencies for the whole sample in the first step in order to describe dementia-specific care structures. In the second step, factor analysis of mixed data (FAMD) with hierarchical clustering (HC) will be applied to analyze relationships between variables. The study was ethically approved in October 2018. DISCUSSION: The typology can be used in future studies to define the context of care units in nursing homes. This may improve the interpretation of findings from future studies that investigated interventions in nursing homes. IMPACT: The typology will visualize and describe the complexity of contextual characteristics of several care units.

[Delayed neuropsychological sequelae after carbon monoxide poisoning]. / Verzögerte Kohlenmonoxidenzephalopathie.

Carbon monoxide poisoning is a very common intoxication worldwide. Its clinical manifestations vary from symptoms like mild headache and dizziness to more serious issues including death. Less well known are symptoms that occur with a delay of 2-40 days, such as movement disorders, cognitive impairment or affective disorders. In this article, we present a case of carbon monoxide poisoning with a delayed neurological sequela. The following review summarizes the literature on clinical presentation, diagnostic options, pathophysiology and therapy of this disease.

Alpha-synuclein activates BV2 microglia dependent on its aggregation state.

Synucleinopathies such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA) are defined by the presence of intracellular alpha-synuclein aggregates in neurons and/or oligodendrocytes. In addition, post mortem tissue analysis revealed profound changes in microglial morphology, indicating microglial activation and neuroinflammation. Thus, alpha-synuclein may directly activate microglia, leading to increased production of key pro-inflammatory cytokines like tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1ß), which in turn modulates the disease progression. The distinct alpha-synuclein species, which mediates the activation of microglia, is not well defined. We hypothesized that microglial activation depends on a specific aggregation state of alpha-synuclein. Here, we show that primarily human fibrillar alpha-synuclein increased the production and secretion of pro-inflammatory cytokines by microglial BV2 cells compared to monomeric and oligomeric alpha-synuclein. BV2 cells also preferentially phagocytosed fibrillar alpha-synuclein compared to alpha-synuclein monomers and oligomers. Microglial uptake of alpha-synuclein fibrils and the consequent activation were time- and concentration-dependent. Moreover, the degree of fibrillization determined the efficiency of microglial internalization. Taken together, our study highlights the specific crosstalk of distinct alpha-synuclein species with microglial cells.

Infiltrating T lymphocytes reduce myeloid phagocytosis activity in synucleinopathy model.

BACKGROUND: Synucleinopathies comprise a group of neurodegenerative diseases associated with abnormal accumulation of α-synuclein. One of the key factors that contribute to the progression of synucleinopathies is neuroinflammation. However, the role of lymphocytes in synucleinopathies like Parkinson's disease (PD) remains largely unclear. METHODS: To investigate how lymphocytes impact synucleinopathies, human wild-type α-synuclein (WTS) transgenic mice were crossed with mice lacking mature lymphocytes (Rag2(-/-)). In this in vivo model, we quantified α-synuclein aggregation in the substantia nigra (SN) and striatum and determined the numbers of innate and adaptive immune cells in the central nervous system (CNS). The activation state of resident and infiltrated CNS myeloid cells (M1 vs. M2) was further classified by gene and protein expression analyses. The impact of T and B lymphocytes on the phagocytic activity of microglia in the presence of α-synuclein aggregates was addressed in BV2 microglia in vitro. RESULTS: Compared to WTS(+) Rag2(+/+) mice, where T but not B lymphocytes infiltrated the CNS, decreased amounts of α-synuclein aggregates were found in WTS(+) Rag2(-/-) mice devoid of mature lymphocytes. The presence of T lymphocytes did not alter the number of Iba1(+) microglia but increased the frequency of the CD11b(+) CD45(hi) population in the CNS, indicative of an increased number of infiltrated macrophages. Moreover, the M1 phenotype was more prominent in WTS(+) Rag2(+/+) mice, whereas the M2 activation state was dominating in the absence of lymphocytes in WTS(+) Rag2(-/-) mice. In vitro, in the presence of T but not B lymphocytes, significantly less α-synuclein was phagocytosed by BV2 microglia, further supporting the prevalence of the M1 phenotype in the presence of T lymphocytes. CONCLUSIONS: Peripheral T lymphocytes strongly contribute to increased α-synuclein pathology via modulation of CNS myeloid cell function. In the presence of T lymphocytes, microglia phagocytosis of aggregated α-synuclein is reduced, which increases the severity of synucleinopathy.

Acclimations to light quality on plant and leaf level affect the vulnerability of pepper (Capsicum annuum L.) to water deficit.

We investigated the influence of light quality on the vulnerability of pepper plants to water deficit. For this purpose plants were cultivated either under compact fluorescence lamps (CFL) or light-emitting diodes (LED) providing similar photon fluence rates (95 µmol m(-2) s(-1)) but distinct light quality. CFL emit a wide-band spectrum with dominant peaks in the green and red spectral region, whereas LEDs offer narrow band spectra with dominant peaks at blue (445 nm) and red (665 nm) regions. After one-week acclimation to light conditions plants were exposed to water deficit by withholding irrigation; this period was followed by a one-week regeneration period and a second water deficit cycle. In general, plants grown under CFL suffered more from water deficit than plants grown under LED modules, as indicated by the impairment of the photosynthetic efficiency of PSII, resulting in less biomass accumulation compared to respective control plants. As affected by water shortage, plants grown under CFL had a stronger decrease in the electron transport rate (ETR) and more pronounced increase in heat dissipation (NPQ). The higher amount of blue light suppressed plant growth and biomass formation, and consequently reduced the water demand of plants grown under LEDs. Moreover, pepper plants exposed to high blue light underwent adjustments at chloroplast level (e.g., higher Chl a/Chl b ratio), increasing the photosynthetic performance under the LED spectrum. Differently than expected, stomatal conductance was comparable for water-deficit and control plants in both light conditions during the stress and recovery phases, indicating only minor adjustments at the stomatal level. Our results highlight the potential of the target-use of light quality to induce structural and functional acclimations improving plant performance under stress situations.

Probing gene function in Candida albicans wild-type strains by Cas9-facilitated one-step integration of two dominant selection markers: a systematic analysis of recombination events at the target locus.

The adaptation of gene deletion methods based on the CRISPR-Cas9 system has facilitated the genetic manipulation of the pathogenic yeast Candida albicans, because homozygous mutants of this diploid fungus can now be generated in a single step, allowing the rapid screening of candidate genes for their involvement in a phenotype of interest. However, the Cas9-mediated double-strand breaks at the target site may result in an undesired loss of heterozygosity (LOH) on the affected chromosome and cause phenotypic alterations that are not related to the function of the investigated gene. In our present study, we harnessed Cas9-facilitated gene deletion to probe a set of genes that are constitutively overexpressed in strains containing hyperactive forms of the transcription factor Mrr1 for a possible contribution to the fluconazole resistance of such strains. To this aim, we used gene deletion cassettes containing two different dominant selection markers, caSAT1 and HygB, which confer resistance to nourseothricin and hygromycin, respectively, for simultaneous genomic integration in a single step, hypothesizing that this would minimize undesired LOH events at the target locus. We found that selection for resistance to both nourseothricin and hygromycin strongly increased the proportion of homozygous deletion mutants among the transformants compared with selection on media containing only one of the antibiotics, but it did not avoid undesired LOH events. Our results demonstrate that LOH on the target chromosome is a significant problem when using Cas9 for the generation of C. albicans gene deletion mutants, which demands a thorough examination of recombination events at the target site. IMPORTANCE: Candida albicans is one of the medically most important fungi and a model organism to study fungal pathogenicity. Investigating gene function in this diploid yeast has been facilitated by the adaptation of gene deletion methods based on the bacterial CRISPR-Cas9 system, because they enable the generation of homozygous mutants in a single step. We found that, in addition to increasing the efficiency of gene replacement by selection markers, the Cas9-mediated double-strand breaks also result in frequent loss of heterozygosity on the same chromosome, even when two different selection markers were independently integrated into the two alleles of the target gene. Since loss of heterozygosity for other genes can result in phenotypic alterations that are not caused by the absence of the target gene, these findings show that it is important to thoroughly analyze recombination events at the target locus when using Cas9 to generate gene deletion mutants in C. albicans.

Multiple instance ensembling for paranasal anomaly classification in the maxillary sinus.

PURPOSE: Paranasal anomalies are commonly discovered during routine radiological screenings and can present with a wide range of morphological features. This diversity can make it difficult for convolutional neural networks (CNNs) to accurately classify these anomalies, especially when working with limited datasets. Additionally, current approaches to paranasal anomaly classification are constrained to identifying a single anomaly at a time. These challenges necessitate the need for further research and development in this area. METHODS: We investigate the feasibility of using a 3D convolutional neural network (CNN) to classify healthy maxillary sinuses (MS) and MS with polyps or cysts. The task of accurately localizing the relevant MS volume within larger head and neck Magnetic Resonance Imaging (MRI) scans can be difficult, but we develop a strategy which includes the use of a novel sampling technique that not only effectively localizes the relevant MS volume, but also increases the size of the training dataset and improves classification results. Additionally, we employ a Multiple Instance Ensembling (MIE) prediction method to further boost classification performance. RESULTS: With sampling and MIE, we observe that there is consistent improvement in classification performance of all 3D ResNet and 3D DenseNet architecture with an average AUPRC percentage increase of 21.86 ± 11.92% and 4.27 ± 5.04% by sampling and 28.86 ± 12.80% and 9.85 ± 4.02% by sampling and MIE, respectively. CONCLUSION: Sampling and MIE can be effective techniques to improve the generalizability of CNNs for paranasal anomaly classification. We demonstrate the feasibility of classifying anomalies in the MS. We propose a data enlarging strategy through sampling alongside a novel MIE strategy that proves to be beneficial for paranasal anomaly classification in the MS.

Alterations to sphingolipid metabolism from antipsychotic administration in healthy volunteers are restored following the use of cannabidiol.

Randomized clinical trials substantiate cannabidiol (CBD) as a next-generation antipsychotic, effective in alleviating positive and negative symptoms associated with psychosis, while minimising the adverse effects seen with established treatments. Although the mechanisms remain debated, CBD is known to induce drug-responsive changes in lipid-based retrograde neurotransmitters. Lipid aberrations are also frequently observed with antipsychotics, which may contribute to their efficacy or increase the risk of undesirables, including metabolic dysfunction, obesity and dyslipidaemia. Our study investigated CBD's impact following lipid responses triggered by interaction with second-generation antipsychotics (SGA) in a randomized phase I safety study. Untargeted mass spectrometry assessed the lipidomic profiles of human sera, collected from 38 healthy volunteers. Serum samples were obtained prior to commencement of any medication (t = 0), 3 days after consecutive administration of one of the five, placebo-controlled, treatment arms designed to achieve steady-state concentrations of each SGA (amisulpride, 150 mg/day; quetiapine, 300 mg/day; olanzapine 10 mg/day; risperidone, 3 mg/day), and after six successive days of SGA treatment combined with CBD (800 mg/day). Receiver operating characteristics (ROC) refined 3712 features to a putative list of 15 lipids significantly altered (AUC > 0.7), classified into sphingolipids (53 %), glycerolipids (27 %) and glycerophospholipids (20 %). Targeted mass spectrometry confirmed reduced sphingomyelin and ceramide levels with antipsychotics, which mapped along their catabolic pathway and were restored by CBD. These sphingolipids inversely correlated with body weight after olanzapine, quetiapine, and risperidone treatment, where CBD appears to have arrested or attenuated these effects. Herein, we propose CBD may alleviate aberrant sphingolipid metabolism and that further investigation into sphingolipids as markers for monitoring side effects of SGAs and efficacy of CBD is warranted.

Reduced olfactory bulb volume accompanies olfactory dysfunction after mild SARS-CoV-2 infection.

Despite its high prevalence, the determinants of smelling impairment in COVID-19 remain not fully understood. In this work, we aimed to examine the association between olfactory bulb volume and the clinical trajectory of COVID-19-related smelling impairment in a large-scale magnetic resonance imaging (MRI) analysis. Data of non-vaccinated COVID-19 convalescents recruited within the framework of the prospective Hamburg City Health Study COVID Program between March and December 2020 were analyzed. At baseline, 233 participants underwent MRI and neuropsychological testing as well as a structured questionnaire for olfactory function. Between March and April 2022, olfactory function was assessed at follow-up including quantitative olfactometric testing with Sniffin' Sticks. This study included 233 individuals recovered from mainly mild to moderate SARS-CoV-2 infections. Longitudinal assessment demonstrated a declining prevalence of self-reported olfactory dysfunction from 67.1% at acute infection, 21.0% at baseline examination and 17.5% at follow-up. Participants with post-acute self-reported olfactory dysfunction had a significantly lower olfactory bulb volume at baseline than normally smelling individuals. Olfactory bulb volume at baseline predicted olfactometric scores at follow-up. Performance in neuropsychological testing was not significantly associated with the olfactory bulb volume. Our work demonstrates an association of long-term self-reported smelling dysfunction and olfactory bulb integrity in a sample of individuals recovered from mainly mild to moderate COVID-19. Collectively, our results highlight olfactory bulb volume as a surrogate marker that may inform diagnosis and guide rehabilitation strategies in COVID-19.

Computer-Aided Diagnosis of Maxillary Sinus Anomalies: Validation and Clinical Correlation.

OBJECTIVE: Computer aided diagnostics (CAD) systems can automate the differentiation of maxillary sinus (MS) with and without opacification, simplifying the typically laborious process and aiding in clinical insight discovery within large cohorts. METHODS: This study uses Hamburg City Health Study (HCHS) a large, prospective, long-term, population-based cohort study of participants between 45 and 74 years of age. We develop a CAD system using an ensemble of 3D Convolutional Neural Network (CNN) to analyze cranial MRIs, distinguishing MS with opacifications (polyps, cysts, mucosal thickening) from MS without opacifications. The system is used to find correlations of participants with and without MS opacifications with clinical data (smoking, alcohol, BMI, asthma, bronchitis, sex, age, leukocyte count, C-reactive protein, allergies). RESULTS: The evaluation metrics of CAD system (Area Under Receiver Operator Characteristic: 0.95, sensitivity: 0.85, specificity: 0.90) demonstrated the effectiveness of our approach. MS with opacification group exhibited higher alcohol consumption, higher BMI, higher incidence of intrinsic asthma and extrinsic asthma. Male sex had higher prevalence of MS opacifications. Participants with MS opacifications had higher incidence of hay fever and house dust allergy but lower incidence of bee/wasp venom allergy. CONCLUSION: The study demonstrates a 3D CNN's ability to distinguish MS with and without opacifications, improving automated diagnosis and aiding in correlating clinical data in population studies. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

ReTimeML: a retention time predictor that supports the LC-MS/MS analysis of sphingolipids.

The analysis of ceramide (Cer) and sphingomyelin (SM) lipid species using liquid chromatography-tandem mass spectrometry (LC-MS/MS) continues to present challenges as their precursor mass and fragmentation can correspond to multiple molecular arrangements. To address this constraint, we developed ReTimeML, a freeware that automates the expected retention times (RTs) for Cer and SM lipid profiles from complex chromatograms. ReTimeML works on the principle that LC-MS/MS experiments have pre-determined RTs from internal standards, calibrators or quality controls used throughout the analysis. Employed as reference RTs, ReTimeML subsequently extrapolates the RTs of unknowns using its machine-learned regression library of mass-to-charge (m/z) versus RT profiles, which does not require model retraining for adaptability on different LC-MS/MS pipelines. We validated ReTimeML RT estimations for various Cer and SM structures across different biologicals, tissues and LC-MS/MS setups, exhibiting a mean variance between 0.23 and 2.43% compared to user annotations. ReTimeML also aided the disambiguation of SM identities from isobar distributions in paired serum-cerebrospinal fluid from healthy volunteers, allowing us to identify a series of non-canonical SMs associated between the two biofluids comprised of a polyunsaturated structure that confers increased stability against catabolic clearance.

Self-supervised learning for classifying paranasal anomalies in the maxillary sinus.

PURPOSE: Paranasal anomalies, frequently identified in routine radiological screenings, exhibit diverse morphological characteristics. Due to the diversity of anomalies, supervised learning methods require large labelled dataset exhibiting diverse anomaly morphology. Self-supervised learning (SSL) can be used to learn representations from unlabelled data. However, there are no SSL methods designed for the downstream task of classifying paranasal anomalies in the maxillary sinus (MS). METHODS: Our approach uses a 3D convolutional autoencoder (CAE) trained in an unsupervised anomaly detection (UAD) framework. Initially, we train the 3D CAE to reduce reconstruction errors when reconstructing normal maxillary sinus (MS) image. Then, this CAE is applied to an unlabelled dataset to generate coarse anomaly locations by creating residual MS images. Following this, a 3D convolutional neural network (CNN) reconstructs these residual images, which forms our SSL task. Lastly, we fine-tune the encoder part of the 3D CNN on a labelled dataset of normal and anomalous MS images. RESULTS: The proposed SSL technique exhibits superior performance compared to existing generic self-supervised methods, especially in scenarios with limited annotated data. When trained on just 10% of the annotated dataset, our method achieves an area under the precision-recall curve (AUPRC) of 0.79 for the downstream classification task. This performance surpasses other methods, with BYOL attaining an AUPRC of 0.75, SimSiam at 0.74, SimCLR at 0.73 and masked autoencoding using SparK at 0.75. CONCLUSION: A self-supervised learning approach that inherently focuses on localizing paranasal anomalies proves to be advantageous, particularly when the subsequent task involves differentiating normal from anomalous maxillary sinuses. Access our code at https://github.com/mtec-tuhh/self-supervised-paranasal-anomaly .