Suplementação de selênio para tratamento e prevenção de doenças: uma overview de revisões sistemáticas Cochrane

Contextualização: O selênio é um componente fundamental em uma série de reações orgânicas que protegem contra o estresse oxidativo e com potencial para tratar e prevenir doenças, segundo a literatura. Objetivos: Sumarizar as evidências de revisões sistemáticas da Cochrane, referentes à efetividade da suplementação de selênio para tratamento e prevenção de doenças. Métodos: Trata-se de overview de revisões sistemáticas Cochrane. Procedeu-se à busca na Cochrane Library (2024), sendo utilizado o descritor "SELENIUM". Todas as revisões sistemáticas de ensaios clínicos foram incluídas. O desfecho primário de análise foi a melhora clínica, a redução dos sintomas ou a prevenção da doença. Resultados: Sete estudos foram incluídos, totalizando 122 ensaios clínicos e 50.267 participantes. Discussão: Há evidência com alto grau de certeza, segundo as revisões sistemáticas realizadas pela Cochrane, de que a suplementação de selênio não reduz o risco de câncer. Pode haver algum benefício para redução de episódios de sepse em crianças com prematuridade extrema, mas o nível de evidência é bastante limitado nesse caso, devido a reduzida amostragem e alta heterogeneidade nos estudos.

Telas de proteção em habitações para prevenção de doenças transmitidas por mosquitos: sinopse baseada em evidências

Contexto e objetivo: A transmissão de doenças por mosquitos afeta a população e a economia de todo o mundo. Há um número considerável de doenças que podem ser transmitidas por mosquitos, com destaque para a malária e a dengue, endêmica em regiões tropicais. Evidentemente, medidas preventivas são imprescindíveis para a redução da transmissão. Avaliar as evidências de efetividade das telas de proteção com e sem inseticida para prevenção de doenças transmitidas por mosquitos. Métodos: Trata-se de sinopse baseada em evidências. Procedeu-se à busca por estudos que associavam o uso de telas de proteção contra mosquitos à redução do contágio de doenças transmitidas por mosquitos em três bases de dados: PubMed (1966-2024), Portal BVS (1982-2024) e Epistemonikos (2024) e também no metabuscador de evidências TRIP DATABASE (2024). O desfecho de análise envolveu a efetividade das telas de proteção na redução de doenças transmitidas por mosquitos. Resultados: Foram encontradas 307 citações. Seis estudos (1 revisão sistemática e 5 ensaios clínicos) foram incluídos. Discussão: A maioria dos estudos envolveu a colocação de telas de proteção com inseticida, havendo evidência de alta certeza para redução de mortalidade por malária e redução na entrada de mosquitos nas habitações, mesmo com redes sem inseticida. Conclusões: Embora não haja robustez na evidência da efetividade das telas de proteção sem inseticidas contra mosquitos transmissores de doenças, o que demanda a necessidade de realização de novos estudos prospectivos, parece lícita e benéfica a utilização de telas de proteção em regiões endêmicas para doenças transmitidas por esses vetores.

Bacterial biofilm formation on headpieces of Cochlear implants.

INTRODUCTION: Bacterial biofilm formation on medical devices, such as Cochlear implants (CI), can lead to chronic infections. Not only the inner parts of the implant but also the externally located headpiece might be associated with prolonged superficial skin eczema resulting in the inability of wearing the headpiece. In this study, the surface of three CI headpieces from different manufacturers were examined for bacterial biofilm formation. MATERIALS AND METHODS: Two bacterial species associated with implant-related infections were tested: Pseudomonas aeruginosa (ATCC9027) and Staphylococcus aureus (ATCC6538). Biofilms were formed over 24 h in tryptic soy broth at 36 °C. Biofilm formation was detected in form of biomass measurement by crystal violet staining. CI headpiece dummies of three manufacturers were used. RESULTS: Both tested bacterial species formed biofilms on the examined CI headpiece-surfaces in a species-dependent manner with higher biofilm formation of P. aeruginosa. For both, S. aureus and P. aeruginosa, biofilm formation on the CI components was comparable to a polystyrene control surface. Between the three manufacturers, no significant difference in biofilm formation was found. DISCUSSION: The tested bacteria displayed biofilm formation on the CI headpieces in a species-specific manner with higher amount of biofilm formed by P. aeruginosa. The biofilm formation was comparable between the manufacturers. In this study, an enhanced biofilm formation on CI headpieces could not be demonstrated. These in vitro tests suggest a minor role of bacterial biofilm on the CI headpiece in skin infections under the CI headpiece.

[Nodal metastasis and value of neck dissection in T1/2 oropharyngeal and hypopharyngeal carcinomas]. / Nodale Metastasierung und Stellenwert der Neck Dissection bei T1/2-Oro- und Hypopharynxkarzinomen.

BACKGROUND: Due to heterogeneous data, the indication for elective neck dissection (END) in patients with squamous cell carcinoma of the hypopharynx and oropharynx (HPSCC and OPSCC) in stages T1/2N0 is somewhat unclear. Therefore, in this multicenter study, we performed detailed analysis of the metastatic behavior of HPSCC and OPSCC. MATERIAL AND METHODS: The nodal metastatic patterns of 262 HPSCC and OPSCC patients who had undergone surgery was retrospectively investigated. In addition, recurrence-free and overall survival were recorded. Furthermore, a systematic literature review on the topic was completed. RESULTS: In patients with HPSCC, a discrepancy between clinical and pathologic N status was recorded in 62.1% of patients vs. 52.4% for p16- OPSCC, and 43.6% for p16+ OPSCC. The occult metastasis rate in cT1/2cN0 primary tumors was 38.9% for HPSCC vs. 17.8% (p16- OPSCC) and 11.1% (p16+ OPSCC). Contralateral metastases occurred in 22.2% of cases for HPSCC at stages cT1/2cN0, compared to only 9.1% for p16- OPSCC, and 0% for p16+ OPSCC patients.Patients with p16+ OPSCC had better recurrence-free and overall survival than p16- OPSCC and HPSCC patients. A direct association between patient survival and the extent of neck surgical therapy could not be demonstrated in our patients. CONCLUSION: Patients with HPSCC are at risk for bilateral neck metastases from stage cT1/2cN0, justifying bilateral END. Patients with T1/2 OPSCC present with occult metastases ipsilaterally in >20% of cases; however, the risk for contralateral occult metastasis is <10%. Hence, in strictly lateralized cT1/2CN0 tumors, omission of contralateral END may be considered.

Heavy arch: from inflammatory bowel diseases to metabolic disorders.

BACKGROUND: Metabolic disorders and inflammatory bowel diseases (IBD) have captured the globe during Westernisation of lifestyle and related dietary habits over the last decades. Both disease entities are characterised by complex and heterogeneous clinical spectra linked to distinct symptoms and organ systems which, on a first glimpse, do not have many commonalities in clinical practice. However, experimental studies indicate a common backbone of inflammatory mechanisms in metabolic diseases and gut inflammation, and emerging clinical evidence suggests an intricate interplay between metabolic disorders and IBD. OBJECTIVE: We depict parallels of IBD and metabolic diseases, easily overlooked in clinical routine. DESIGN: We provide an overview of the recent literature and discuss implications of metabolic morbidity in patients with IBD for researchers, clinicians and healthcare providers. CONCLUSION: The Western lifestyle and diet and related gut microbial perturbation serve as a fuel for metabolic inflammation in and beyond the gut. Metabolic disorders and the metabolic syndrome increasingly affect patients with IBD, with an expected negative impact for both disease entities and risk for complications. This concept implies that tackling the obesity pandemic exerts beneficial effects beyond metabolic health.

Innate Immunity and MASLD.

Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as the most common liver disease worldwide in recent years. MASLD commonly presents as simple hepatic steatosis, but ~25% of patients develop liver inflammation, progressive fibrosis, liver cirrhosis and related hepatocellular carcinoma. Liver inflammation and the degree of fibrosis are key determinants of the prognosis. The pathophysiology of liver inflammation is incompletely understood and involves diverse factors and specifically innate and adaptive immune responses. More specifically, diverse mediators of innate immunity such as proinflammatory cytokines, adipokines, inflammasomes and various cell types like mononuclear cells, macrophages and natural killer cells are involved in directing the inflammatory process in MASLD. The activation of innate immunity is driven by various factors including excess lipids and lipotoxicity, insulin resistance and molecular patterns derived from gut commensals. Targeting pathways of innate immunity might therefore appear as an attractive therapeutic strategy in the future management of MASLD and possibly its complications.

[Results of a survey on the current management of chronic rhinosinusitis with nasal polyps in Germany]. / Ergebnisse einer Umfrage zur aktuellen Behandlung der chronischen Rhinosinusitis mit nasalen Polypen.

INTRODUCTION: With a prevalence of 0.55% to 4%, chronic rhinosinusitis with nasal polyps (CRSwNP) is a relevant part of the daily work of German otolaryngologists. The aim of the questionnaire-based data collection was to assess the current treatment status of CRSwNP in Germany. MATERIAL AND METHODS: For this purpose, 24 questions within an anonymized online questionnaire were sent to all German ENT departments. RESULTS: Of 160 contacted ENT departments, 50 participated in the survey (31.3%). Among these, 76% performed more than 100 sinus surgeries annually and 38% treated more than 50 patients with biologics. Saline irrigations (80%) and intranasal glucocorticoids (GCS, 96%) were the most common conservative therapies. Systemic GCSs (52%) and intranasal GCS irrigation (20%) were less common. 80% of departments used biologics in the therapy of CRSwNP with an overall preference for dupilumab (70%). For therapy of aspirin intolerance, biologics (52%) were preferred to aspirin desensitization (26%). Prior to treatment with biologics clinical workup included the nasal polyp score (90%), the SNOT-22 questionnaire (84%), surrogate markers of type 2 inflammation (60%-72%), and computer tomography (50%). Final treatment success was assessed after 24 weeks (50%). CONCLUSION: Mostly, the responding departments followed German and European recommendations for diagnosis and therapy of CRSwNP. Therapy with biologics is widely used. The value of preoperative systemic GCS and the frequent performance of CT before initiation of therapy with a biologic should be debated in regard to its currently widespread use.

Concordance Analysis of the Pressure Chamber and Tubomanometer According to Estève for the Determination of Eustachian Tube Opening Pressure.

INTRODUCTION: For the diagnosis of Eustachian tube dysfunction (ETD), clinical procedures such as tympanometry, micro-otoscopy, and maneuvers according to Toynbee and Valsalva only allow an indirect assessment for the moment. With a prevalence of up to 5%, the selection of patients with ETD and its subtypes is clinically relevant. Dynamic methods of Eustachian tube function assessment include a hypo/hyperbaric pressure chamber and Estève's tubomanometer (TMM). One method of assessing ETD is the evaluation of Eustachian tube opening pressure (ETOP). MATERIAL AND METHODS: We performed a concordance analysis between pressure chamber and TMM to determine ETOP. For this purpose, we analyzed the measurements of both methods from 28 healthy subjects using Bland-Altman plots, regression according to Passing-Bablok and Lin's concordance correlations coefficient. The maximum tolerated clinical deviation of measured values was set at 10%. RESULTS: A maximum of 53 measurements of ETOP between pressure chamber and TMM were compared. Mean ETOP for TMM was 28.7 hPa, passive opening was 32 hPa, Toynbee maneuver was 28.4 hPa, and Valsalva maneuver was 54.6 hPa. Concordance analysis revealed following results: passive opening versus TMM: Bland-Altman mean difference 3.3 hPa, limits of agreement ±31.8 hPa; Passing-Bablok regression y = 0.67 x + 9.36; Lin's rccc = 0.18. Toynbee versus TMM: Bland-Altman mean difference 0.7 hPa, limits of agreement ±35.8 hPa; Passing-Bablok regression y = 0.47x + 14.03; Lin's rccc = 0.14. Valsalva versus TMM: Bland-Altman mean difference 24.2 hPa, limits of agreement ±117.5 hPa; Passing-Bablok regression y = 0.17x + 25.12; Lin's rccc = 0.18. CONCLUSION: Estève's tubomanometer and pressure chamber measurements of ETOP are not concordant. The two methods cannot be interchanged without reservation.

Two different methods to digitally visualize continuous electrocochleography potentials during cochlear implantation: a first description of feasibility.

PURPOSE: The study explores the potential of real-time electrocochleographic potentials (ECochG) visualization during electrode insertion using digital microscopes such as RoboticScope (BHS®). Collaborative software development of the MAESTRO Software (MED-EL®) offers continuous ECochG monitoring during implantation and postoperative hearing evaluation, addressing previous time constraints. The study aims to assess software applicability and the impact of real-time visualization on long-term residual hearing preservation. METHODS: Eight patients with residual hearing underwent cochlear implantation with Flex26 or Flex28 electrode according to the Otoplan evaluation. ECochG responses were measured and visualized during electrode insertion, with insertion times recorded. Two randomized display methods (graph and arrows) tracked ECochG potentials. Postoperative behavioral thresholds determined hearing preservation. Successful real-time intraoperative ECochG visualization was achieved in all cases, enabling surgeon adaptation. Mean electrode insertion time was 114 s, with postoperative thresholds comparable to preoperative values. Visualization did not affect surgeon workload. ECochG amplitudes differed between patients with and without residual hearing. CONCLUSION: The study demonstrates effective implementation of advanced ECochG software combined with real-time visualization, enabling residual hearing preservation during CI. Visualization had no apparent effect on surgeon performance or workload. Future investigation involving a larger population will assess the long-term impact of ECochG on hearing threshold and structure preservation.

Digital live imaging of intraoperative electrocochleography during cochlear implantation: the first 50 patients.

INTRODUCTION: Real-time visualization of intraoperative electrocochleography (ECochG) potentials via a digital microscope during cochlear implantation can provide direct feedback during electrode insertion. The aim of this prospective, randomized study of 50 patients was to obtain long-term data with a focus on residual hearing preservation and speech understanding. MATERIAL AND METHODS: Cochlear implantations were performed in 50 patients (26 female, 24 male) with residual hearing using a digital microscope. Patients were randomized into two groups. Intraoperative ECochG potentials were either displayed directly in the surgeon's field of view (picture-in-picture display, PiP) or not directly in the field of view (without picture-in-picture display, without PiP). Residual hearing preservation and speech comprehension were recorded within a 1-year follow-up period, compared between groups (PiP versus without PiP) and to a control group of 26 patients implanted without ECochG. RESULTS: Mean insertion time was significantly longer in the picture-in-picture group (p = 0.025). Residual hearing preservation after 6 weeks at 250 Hz was significantly better in the picture-in-picture group (p = 0.017). After one year, 76% of patients showed residual hearing in the picture-in-picture group (62% without picture-in-picture technique, p = n.s.). Use of the picture-in-picture technique resulted in better long-term pure tone residual hearing preservation at 250, 500, and 1000 Hz. Speech intelligibility improved by 46% in the picture-in-picture group (38% without picture-in-picture). DISCUSSION: This study is the first to describe long-term results in a large cohort of cochlear implant patients in whom digital visualization of intraoperative ECochG was used. Our results show that visualization of intraoperative ECochG has a positive effect on residual hearing preservation.

[Increased rate of complications of pediatric acute otitis media and sinusitis in 2022/2023]. / Häufung von Komplikationen der akuten Otitis media und Sinusitis bei Kindern 2022/2023.

BACKGROUND: Acute mastoiditis and orbital complications of acute rhinosinusitis are among the most common complications of pediatric infections in otolaryngology. OBJECTIVE: The aim of this study was to investigate the frequency of pediatric acute mastoiditis in the setting of acute otitis media as well as pediatric orbital complications in the setting of acute rhinosinusitis. Data from before the pandemic were compared to data after the end of the COVID-19 restrictions. MATERIALS AND METHODS: Included were hospitalized children who presented with acute mastoiditis from acute otitis media or with orbital complications from acute rhinosinusitis during the period from April 2017 to March 2023. Compared were three periods using descriptive statistics: April 2017 to March 2020 (before the pandemic in Germany), April 2020 to March 2022 (during the contact restrictions of the pandemic), and April 2022 to March 2023 (after the contact restrictions were lifted). RESULTS: A total of 102 children (43 with acute mastoiditis, 42%, and 59 with orbital complications of acute sinusitis, 58%) were included. During the 2022/2023 period, more than twice as many children with acute mastoiditis and approximately three times as many children with orbital complications of acute rhinosinusitis were hospitalized compared to the average of the periods 2017/2018, 2018/2019, and 2019/2020. In the 2021/2022 period, the number of these patients was below the average of previous years. CONCLUSION: This year's seasonal cluster of upper respiratory tract infections is associated with a higher-than-average incidence of orbital complications and mastoiditis.

24-Norursodeoxycholic acid ameliorates experimental alcohol-related liver disease and activates hepatic PPARγ.

Background & Aims: Alcohol-related liver disease (ALD) is a global healthcare challenge with limited treatment options. 24-Norursodeoxycholic acid (NorUDCA) is a synthetic bile acid with anti-inflammatory properties in experimental and human cholestatic liver diseases. In the present study, we explored the efficacy of norUDCA in experimental ALD. Methods: NorUDCA was tested in a preventive and therapeutic setting in an experimental ALD model (Lieber-DeCarli diet enriched with ethanol). Liver disease was phenotypically evaluated using histology and biochemical methods, and anti-inflammatory properties and peroxisome proliferator-activated receptor gamma activation by norUDCA were evaluated in cellular model systems. Results: NorUDCA administration ameliorated ethanol-induced liver injury, reduced hepatocyte death, and reduced the expression of hepatic pro-inflammatory cytokines including tumour necrosis factor (Tnf), Il-1ß, Il-6, and Il-10. NorUDCA shifted hepatic macrophages towards an anti-inflammatory M2 phenotype. Further, norUDCA administration altered the composition of the intestinal microbiota, specifically increasing the abundance of Roseburia, Enterobacteriaceae, and Clostridum spp. In a therapeutic model, norUDCA also ameliorated ethanol-induced liver injury. Moreover, norUDCA suppressed lipopolysaccharide-induced IL-6 expression in human peripheral blood mononuclear cells and evoked peroxisome proliferator-activated receptor gamma activation. Conclusions: NorUDCA ameliorated experimental ALD, protected against hepatic inflammation, and affected gut microbial commensalism. NorUDCA could serve as a novel therapeutic agent in the future management of patients with ALD. Impact and implications: Alcohol-related liver disease is a global healthcare concern with limited treatment options. 24-Norursodeoxycholic acid (NorUDCA) is a modified bile acid, which was proven to be effective in human cholestatic liver diseases. In the present study, we found a protective effect of norUDCA in experimental alcoholic liver disease. For patients with ALD, norUDCA could be a potential new treatment option.

Intraindividual variability of the Eustachian tube function: a longitudinal study in a pressure chamber.

INTRODUCTION: The Eustachian tube (ET) is essential for fast and direct pressure equalisation between middle ear and ambient pressure. It is not yet known to what extent Eustachian tube function in healthy adults changes in a weekly periodicity due to internal and external factors. This question is particularly interesting with regard to scuba divers among whom there is a need to evaluate intraindividual ET function variability. METHODS: Continuous impedance measurement in a pressure chamber was performed three times at one-week intervals between measurements. Twenty healthy participants (40 ears) were enrolled. Using a monoplace hyperbaric chamber, individual subjects were exposed to a standardised pressure profile consisting of a 20 kPa decompression over 1 min, a 40 kPa compression over 2 min, and a 20 kPa decompression over 1 min. Measurements of Eustachian tube opening pressure (ETOP), opening duration (ETOD), and opening frequency (ETOF) were made. Intraindividual variability was assessed. RESULTS: Mean ETOD during compression (actively induced pressure equalisation) on the right side was 273.8 (SD 158.8) ms, 259.4 (157.7) ms, and 249.2 (154.1) ms (Chi-square 7.30, P = 0.026) across weeks 1-3. Mean ETOD for both sides was 265.6 (153.3) ms, 256.1 (154.6) ms, and 245.7 (147.8) ms (Chi-square 10.00, P = 0.007) across weeks 1-3. There were no other significant differences in ETOD, ETOP and ETOF across the three weekly measurements. CONCLUSIONS: This longitudinal study suggests low week-to-week intraindividual variability of Eustachian tube function.

A novel membrane stirrer system enables foam-free biosurfactant production.

Bioreactors are the operative backbone, for example, for the production of biopharmaceuticals, biomaterials in tissue engineering, and sustainable substitutes for chemicals. Still, the Achilles' heel of bioreactors nowadays is the aeration which is based on intense stirring and gas sparging, yielding inherent drawbacks such as shear stress, foaming, and sterility concerns. We present the synergistic combination of simulations and experiments toward a membrane stirrer for the efficient bubble-free aeration of bioreactors. A digital twin of the bioreactor with an integrated membrane-module stirrer (MemStir) was developed with computational fluid dynamics (CFD) studies addressing the determination of fluid mixing, shear rates, and local oxygen concentration. Usability of the MemStir is shown in a foam-free recombinant production process of biosurfactants (rhamnolipids) from glucose with different strains of Pseudomonas putida KT2440 in a 3-L vessel and benchmarked against a regular aerated process. The MemStir delivered a maximal oxygen transfer rate (OTRmax ) of 175 mmol L-1 h-1 in completely foam-free cultivations. With a high space-time yield (STY) of 118 mgRL L-1 h-1 during a fed-batch fermentation, the effectiveness of the novel MemStir is demonstrated. Simulations show the generic value of the MemStir beyond biosurfactant production, for example, for animal cell cultivation.

[Results of a nationwide survey on the treatment of salivary gland diseases in German hospitals]. / Ergebnisse einer deutschlandweiten Umfrage zur Behandlung von Speicheldrüsenerkrankungen im Krankenhaus.

BACKGROUND: Salivary gland diseases are an important part of the work of ENT physicians in hospitals. The treatment strategies depend, among other things, on the doctrine at the respective location. OBJECTIVE: The aim of this questionnaire-based study was to assess the current diagnostic workup and therapeutic strategies for salivary gland diseases in German otorhinolaryngology departments. MATERIALS AND METHODS: A survey was performed using a 25-question online questionnaire sent to all German otorhinolaryngology department directors. RESULTS: The questionnaire was answered by 92 of 175 otorhinolaryngology departments (52.6%). In the diagnosis of salivary gland tumors, a dominance of sonography and MRI was shown. Fine- and core-needle aspiration were not performed by more than 50% of the clinics. The dominant technique for parotidectomy was under microscopic control (82%). In 99% of clinics, EMG was used during resection of the parotid gland for intraoperative monitoring of the facial nerve. There was a trend towards performing partial parotidectomies (85%), lateral parotidectomies (70%), and extracapsular dissections (57%) for benign tumors of the parotid gland. The treatment concepts for malignant tumors were inconsistent. CONCLUSION: In particular, the treatment strategy and extent of surgery for benign and malignant salivary gland tumors differed depending on location. The choice of palliative (drug) therapy was also diverse. Prospective multicenter studies could help to develop evidence-based treatment strategies.

The metabolic nature of inflammatory bowel diseases.

Crohn's disease and ulcerative colitis, phenotypically comprising a spectrum of inflammatory bowel diseases (IBDs), spread globally during the westernization of lifestyle and dietary habits over the past few decades. Here, we review experimental and clinical evidence for the metabolic nature of gut inflammation in IBD and delineate distinct parallels to the inflammatory state in metabolic diseases. Experimental evidence indicates that excessive intake of specific macronutrients in a Western diet fuels an inflammatory response in the gut by exploiting sensors of innate immunity and perturbation of gut microbial metabolism. Genetic IBD risk partly affects metabolism and stress signalling of innate immunity, and immunometabolism controls susceptibility to gut inflammation. Epidemiological and clinical studies indicate that specific nutrients in the Western diet pose a risk for the development of IBD and a poor disease course. Translational studies in IBD indicate perturbation of energy metabolism in immune cells and perturbation of gut microbial metabolism, which can be shaped by diet. In turn, dietary restriction by exclusive enteral nutrition induces remission in patients with IBD. Collectively, these studies support a metabolic underpinning of gut inflammation in IBD as described for metabolic inflammation in obesity and related disorders.

Postacute COVID-19 is Characterized by Gut Viral Antigen Persistence in Inflammatory Bowel Diseases.

BACKGROUND & AIMS: The coronavirus disease 2019 (COVID-19) pandemic has affected populations, societies, and lives for more than 2 years. Long-term sequelae of COVID-19, collectively termed the postacute COVID-19 syndrome, are rapidly emerging across the globe. Here, we investigated whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen persistence underlies the postacute COVID-19 syndrome. METHODS: We performed an endoscopy study with 46 patients with inflammatory bowel disease (IBD) 219 days (range, 94-257) after a confirmed COVID-19 infection. SARS-CoV-2 antigen persistence was assessed in the small and large intestine using quantitative polymerase chain reaction of 4 viral transcripts, immunofluorescence of viral nucleocapsid, and virus cultivation from biopsy tissue. Postacute COVID-19 was assessed using a standardized questionnaire, and a systemic SARS-CoV-2 immune response was evaluated using flow cytometry and enzyme-linked immunosorbent assay at endoscopy. IBD activity was evaluated using clinical, biochemical, and endoscopic means. RESULTS: We report expression of SARS-CoV-2 RNA in the gut mucosa ∼7 months after mild acute COVID-19 in 32 of 46 patients with IBD. Viral nucleocapsid protein persisted in 24 of 46 patients in gut epithelium and CD8+ T cells. Expression of SARS-CoV-2 antigens was not detectable in stool and viral antigen persistence was unrelated to severity of acute COVID-19, immunosuppressive therapy, and gut inflammation. We were unable to culture SARS-CoV-2 from gut tissue of patients with viral antigen persistence. Postacute sequelae of COVID-19 were reported from the majority of patients with viral antigen persistence, but not from patients without viral antigen persistence. CONCLUSION: Our results indicate that SARS-CoV-2 antigen persistence in infected tissues serves as a basis for postacute COVID-19. The concept that viral antigen persistence instigates immune perturbation and postacute COVID-19 requires validation in controlled clinical trials.

Influence of 30 and 60 Min of Hypobaric Hypoxia in Simulated Altitude of 15,000 ft on Human Proteome Profile.

The human body reacts to hypobaric hypoxia, e.g., during a stay at high altitude, with several mechanisms of adaption. Even short-time exposition to hypobaric hypoxia leads to complex adaptions. Proteomics facilitates the possibility to detect changes in metabolism due to changes in proteins. The present study aims to identify time-dependent changes in protein expression due to hypobaric hypoxia for 30 and 60 min at a simulated altitude of 15,000 ft. N = 80 male subjects were randomized and assigned into four different groups: 40 subjects to ground control for 30 (GC30) and 60 min (GC60) and 40 subjects to 15,000 ft for 30 (HH30) and 60 min (HH60). Subjects in HH30 and HH60 were exposed to hypobaric hypoxia in a pressure chamber (total pressure: 572 hPa) equivalent to 15,000 ft for 30 vs. 60 min, respectively. Drawn blood was centrifuged and plasma frozen (-80 °C) until proteomic analysis. After separation of high abundant proteins, protein expression was analyzed by 2-DIGE and MALDI-TOF. To visualize the connected signaling cascade, a bio-informatical network analysis was performed. The present study was approved by the ethical committee of the University of Cologne, Germany. The study registry number is NCT03823677. In comparing HH30 to GC30, a total of seven protein spots had a doubled expression, and 22 spots had decreased gene expression. In a comparison of HH60 to GC60, a total of 27 protein spots were significantly higher expressed. HH60, as compared to GC30, revealed that a total of 37 spots had doubled expression. Vice versa, 12 spots were detected, which were higher expressed in GC30 vs. HH60. In comparison to GC, HH60 had distinct differences in the number of differential protein spots (noticeably more proteins due to longer exposure to hypoxia). There are indicators that changes in proteins are dependent on the length of hypobaric hypoxia. Some proteins associated with hemostasis were differentially expressed in the 60 min comparison.