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Background: In the pandemic, testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by real-time polymerase chain reaction is one of the pillars on which countermeasures are based. Factors limiting the output of laboratories interfere with the effectiveness of public health measures. Conserving reagents by pooling samples in low-probability settings is proposed but may cause dilution and loss of sensitivity. Blood transfusion services had experience in performance of high throughput nucleic acid testing (NAT) analysis and can support the national health system by screening of the inhabitants for SARS-COV-2.
Methods: We evaluated a new approach of a multiple-swab method by simultaneously incubating multiple respiratory swabs in a single tube. Analytical sensitivity was constant up to a total number of 50 swabs. It was consequently applied in the testing of 50 symptomatic patients (5-sample pools) as well as 100 asymptomatic residents of a nursing home (10-sample pools).
Results: The novel method did not cause false-negative results with nonsignificantly differing cycle threshold values between single-swab and multiple-swab NAT. In two routine applications, all minipools containing positive patient samples were correctly identified.
Conclusions: The new method enables countries to increase the total number of testing significantly. The multiple-swab method is able to screen system relevant groups of employees frequently. The example in Germany shows that blood transfusion services can support general health systems with their experience in NAT and their high-throughput instruments. Screening of a huge number of inhabitants is currently the only option to prevent a second infection wave and enable exit strategies in many countries.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can spread from symptomatic patients with COVID-19, but also from asymptomatic individuals. Therefore, robust surveillance and timely interventions are essential for the control of virus spread within the community. In this regard the frequency of testing and speed of reporting, but not the test sensitivity alone, play a crucial role. In order to reduce the costs and meet the expanding demands in real-time RT-PCR (rRT-PCR) testing for SARS-CoV-2, complementary assays, such as rapid antigen tests, have been developed. Rigorous analysis under varying conditions is required to assess the clinical performance of these tests and to ensure reproducible results. We evaluated the sensitivity and specificity of a recently licensed rapid antigen test using 137 clinical samples in two institutions. Test sensitivity was between 88.2-89.6% when applied to samples with viral loads typically seen in infectious patients. Of 32 rRT-PCR positive samples, 19 demonstrated infectivity in cell culture, and 84% of these samples were reactive with the antigen test. Seven full-genome sequenced SARS-CoV-2 isolates and SARS-CoV-1 were detected with this antigen test, with no cross-reactivity against other common respiratory viruses. Numerous antigen tests are available for SARS-CoV-2 testing and their performance to detect infectious individuals may vary. Head-to-head comparison along with cell culture testing for infectivity may prove useful to identify better performing antigen tests. The antigen test analyzed in this study is easy-to-use, inexpensive, and scalable. It can be helpful in monitoring infection trends and thus has potential to reduce transmission.
Background: The current COVID-19 pandemic has led to a surge of research activity. While this research provides important insights, the multitude of studies results in an increasing segmentation of information. To ensure comparability across projects and institutions, standard datasets are needed. Here, we introduce the “German Corona Consensus Dataset” (GECCO), a uniform dataset that uses international terminologies and health IT standards to improve interoperability of COVID-19 data.
Methods: Based on previous work (e.g., the ISARIC-WHO COVID-19 case report form) and in coordination with experts from university hospitals, professional associations and research initiatives, data elements relevant for COVID-19 research were collected, prioritized and consolidated into a compact core dataset. The dataset was mapped to international terminologies, and the Fast Healthcare Interoperability Resources (FHIR) standard was used to define interoperable, machine-readable data formats.
Results: A core dataset consisting of 81 data elements with 281 response options was defined, including information about, for example, demography, anamnesis, symptoms, therapy, medications or laboratory values of COVID-19 patients. Data elements and response options were mapped to SNOMED CT, LOINC, UCUM, ICD-10-GM and ATC, and FHIR profiles for interoperable data exchange were defined.
Conclusion: GECCO provides a compact, interoperable dataset that can help to make COVID-19 research data more comparable across studies and institutions. The dataset will be further refined in the future by adding domain-specific extension modules for more specialized use cases.
Introduction: Prophylaxis with factor VIII (FVIII) concentrates in children with haemophilia A (HA) is current standard of care. The benefit of prophylactic treatment for adult HA patients is not commonly accepted.
Aim: To investigate the benefit of prophylaxis over on‐demand treatment in adult and elderly patients with severe or non‐severe HA in a real‐life setting.
Methods: Data from 163 patients comprising 1202 patient‐years were evaluated for 7.5 (±5.3) years. The effects on the annual bleeding rate (ABR, including spontaneous and traumatic bleeds) of treatment with a plasma‐derived FVIII concentrate, the patient's age and disease severity were investigated. The effect of changing the treatment from on demand to continuous prophylaxis on the patients’ ABRs was further analysed.
Results: Prophylaxis had the greatest effect on the ABRs of patients of any age with severe or non‐severe HA. The difference in ABR of all patients treated on demand (median 31.4; interquartile range (IQR) 27.6; N = 83) compared with those treated prophylactically (median 1.3; IQR 3.6; N = 122) was statistically significant (P < .05), even for patients with non‐severe HA (median 8.4; IQR 15.5; N = 11) vs median 1.5; IQR 4.2 (N = 17), P < .05). Patients, aged up to 88 years, switching from on demand to continuous prophylaxis showed the lowest median ABR (1.1; N = 51) after their regimen change.
Conclusion: Any (even low‐frequency) prophylaxis results in lower ABR than on‐demand treatment. Patients switching to prophylaxis benefitted the most, irrespective of age or HA severity. Prophylactic treatment—even tertiary—is the regimen of choice for patients of any age, including elderly patients, with severe or non‐severe HA.
Purpose: Surgery of KOOS IV vestibular schwannoma remains challenging regarding the balance of extent of tumor resection (EoR) and functional outcome. Our aim was to evaluate the outcome of surgical resection and define a cut-off value for safe resection with low risk for tumor regrowth of KOOS IV vestibular schwannoma.
Methods: All patients presenting at the authors’ institution between 2000 and 2019 with surgically treated KOOS IV vestibular schwannoma were included. Outcome measures included EoR, facial/hearing nerve function, surgical complications and progression of residual tumor during the median follow-up period of 28 months.
Results: In 58 patients, mean tumor volume was 17.1 ± 9.2 cm3, and mean EoR of 81.6 ± 16.8% could be achieved. Fifty-one patients were available for the follow-up analysis. Growth of residual tumor was observed in 11 patients (21.6%) followed by adjuvant treatment with stereotactic radiosurgery or repeat surgery in 15 patients (29.4%). Overall serviceable hearing preservation was achieved in 38 patients (74.5%) and good facial outcome at discharge was observed in 66.7% of patients, significantly increasing to 82.4% at follow-up. Independent predictors for residual tumor growth was EoR ≤ 87% (OR11.1) with a higher EoR being associated with a very low number of residual tumor progression amounting to 7.1% at follow-up (p=0.008).
Conclusions: Subtotal tumor resection is a good therapeutic concept in patients with KOOS IV vestibular schwannoma resulting in a high rate of good hearing and facial nerve function and a very low rate of subsequent tumor progression. The goal of surgery should be to achieve more than 87% of tumor resection to keep residual tumor progression low.
Background Stigma has been considered a significant barrier both in treatment, rehabilitation and help-seeking behaviours of people diagnosed with depression. This study aimed to assess the influence of the type of previous experience with depression on depression stigma, identify the effects of previous experience with depression on stigma and to analyse the effects of stigma on help-seeking attitudes.
Methods A total of 1693 participants with a mean age of 47.2 (SD=18.17) completed the Depression Stigma Scale (DSS), the Attitude Toward Seeking Professional Psychological Help (ATSPPH), and a sociodemographic questionnaire. We categorised participants into four comparison groups: no previous experience with depression (n=479), indirect experience with depression (n=661), direct experience with depression (n=137), and both direct and indirect experience with depression (n=416). Data were analysed using SPSS 24.0.
Results Levels of personal stigma were lower in people who had family and friends experiencing depression in comparison with individuals with no history of depression experience. Better attitudes towards help-seeking were evident in those with lower personal stigma, and worse help-seeking attitudes were associated with higher perceived stigma in the indirect previous experience group.
Limitations Duration of participant exposure to depression was not collected.
Conclusions The individual’s experience with depression influences the development of personal stigmatisation towards depression and plays a role in help-seeking behaviours. Addressing people’s experience of depression might be a practical way of reducing depression stigma and improve help-seeking behaviours.
Traumatische Verletzungen fordern jährlich über fünf Millionen Todesopfer. Sie sind bei unter 45-Jährigen die häufigste Ursache für Tod und körperliche Behinderung dar. Ein Polytrauma verursacht eine schwere Belastung für das Immunsystem und ist häufig von schweren Störungen der Immunregulation gekennzeichnet. Die Immunreaktion übersteigt bei schweren Traumata das für lokale Reparaturmechanismen notwendige Maß, und so kommt es je nach Ausmaß der Verletzungen innerhalb der ersten Minuten bis Stunden zu einer systemischen Hyperinflammation, dem sogenannten Systemischen Inflammatorischen Response- Syndrom (SIRS). Auch in nicht verletzten Organen verursacht SIRS Störungen in der Endothel-Funktion, wodurch die Mikrozirkulation in diesen Organgen beeinträchtigt ist. In der Folge kommt es zu interstitieller Ödembildung, zur Gewebsinfiltration durch Leukozyten und zu Zelluntergang. Diese Prozesse können zur Fehlfunktion von Organen bis hin zum Organversagen, und, da sie häufig in mehreren Organen gleichzeitig ablaufen, auch zum klinisch dann oft schwer beherrschbaren Multiorganversagen (MOV) führen. Auf der anderen Seite stoßen schwere Verletzungen antiinflammatorische Prozesse an, die zu einer ausgeprägten Immunsuppression führen können, dem Kompensatorischen Antiinflammatorischen Response-Syndrom (CARS), mit der Folge, dass polytraumatisierte Patienten erhöht anfällig für infektiöse Komplikationen sind. Die beschriebenen Funktionsstörungen des Immunsystems sind ein wichtiger Mortalitätsfaktor von polytraumatisierten Patienten. Während wir SIRS und seine Folgen über die letzten Jahre immer besser verstehen, mit signifikanten Fortschritten auch für die klinische Handhabung dieser Komplikationen des Polytraumas, ist CARS weit schlechter untersucht.
Während der post-traumatschen Immunantwort spielen nicht nur Zellen der angeborenen, sondern auch solche der erworbenen Immunabwehr eine wichtige Rolle. So sind regulatorische T-Zellen (Treg) entscheidend an der posttraumatischen Immunsuppression beteiligt. Treg beeinflussen die immunologische Homöostase Treg mit einem Arsenal immunsuppressiver Werkzeuge. Sie töten oder beeinflussen beispielsweise antigenpräsentierende Zellen oder T-Effektorzellen und verändern das Zytokinmilieu und metabolische Signalwege. Nach einem Trauma kann eine überschießende Aktivität von Treg die immunologische Balance so beeinträchtigen, dass eine posttraumatische Immunsuppression entsteht oder intensiviert wird. Die hier vorgestellte Studie Ziel dient daher dem besseren Verständnis der Dynamik von Treg nach einer stattgehabten traumatischen Verletzung. Dafür untersuchten wir die Verläufe verschiedener Subpopulationen von Treg im Blut schwer verletzter Patienten. Da der Forschung am Menschen in vivo enge ethische und methodologische Grenzen gesetzt sind, nehmen Tiermodelle in der Traumaforschung einen hohen Stellenwert ein. Daher verglichen wir die an Patienten erhobenen Daten über die posttraumatische Dynamik von Treg mit den Verläufen in einem adäquaten Tiermodell.
Aufgrund der guten anatomischen, physiologischen und genetischen Ähnlichkeit zum Menschen werden Tiermodelle am Schwein zunehmend beliebter. Ein Polytraumamodell am Schwein existiert erst seit wenigen Jahren. Über Treg wurde in diesem Rahmen bisher nicht geforscht. Die Charakterisierung ihres Immunphänotyps und ihrer Dynamik könnte die Anwendbarkeit des Schweine-Modells für Fragen der Trauma-Forschung verbessern und gleichzeitig unser Verständnis der Pathophysiologie posttraumatischer Komplikationen wir SIRS oder Sepsis erhöhen.
Bei 20 Traumapatienten (TP) mit einem Injury Severity Score (ISS) ≥ 16 wurde bei Ankunft in der Notaufnahme, nach einem und nach drei Tagen venöses Blut entnommen. Zehn gesunde Freiwillige (HV) fungierten in der Studie als Kontrollgruppe. Das Polytrauma im Großtiermodell am Schwein bestand aus einer Femurfraktur, einer Leberlazeration, einer Lungenkontusion und einem hämorrhagischen Schock, was einen ISS von 27 ergab. Auf die Traumainduktion folgte die Reanimationsphase und die chirurgische Versorgung der Femurfraktur nach dem damage-control-Prinzip. Die Blutentnahmen erfolgten bei den Versuchstieren vor und sofort nach Trauma, sowie nach 24 und 72 Stunden. Wir verglichen die Dynamik der Verläufe der Treg von TP mit denen von HV und mit Daten aus den Tierversuchen. Es herrscht noch kein wissenschaftlicher Konsens darüber, welche Kombination aus immunologischen Oberflächenmarkern die Identifikation von Treg zuverlässig gewährleisten kann. Dies liegt auch daran, dass Treg eine Gruppe verschiedener Unterpopulationen darstellen. Folglich analysierten wir verschiedene Kombinationen. Wir färbten Cluster of differentiation (CD) 4-positive und CD25-positive (CD4+CD25+), CD4+CD25+forkhead box P3 (FoxP3)+, CD4+CD25+CD127-negative (CD127−) und CD4+CD25+CD127−FoxP3+ Zellen mit Antikörpern und charakterisierten die jeweilige Gruppe mithilfe der Durchflusszytometrie. CD4+CD25+CD127− Treg sind beim Menschen bekannt. Beim Schwein werden sie in dieser Studie erstmalig beschrieben.
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Simple Summary: Glioblastomas are very malignant and essentially incurable brain tumors. One problem is the extensive penetration of tumor cells into the adjacent normal brain tissue. Thus, the testing of novel drugs requires appropriate tumor models, preferentially avoiding animal studies. This paper describes so-called brain tissue slice tandem-culture systems. They consist of a slice of normal brain tissue and a second layer of tumor tissue. The microscopic analysis of these slice tandem-cultures allows for the simultaneous assessment of single cells invading into the normal brain tissue and the space occupying growth of the total tumor mass. It is shown that the direct application of test drugs onto the slices exerts inhibitory effects on both mechanisms. We thus describe a system mimicking the situation in glioblastoma patients. It reduces animal studies, allows for the direct application of test drugs and the precise quantitation of their inhibitory effects on tumor growth and invasion.
Abstract: Glioblastomas (GBMs) are the most malignant brain tumors and are essentially incurable even after extensive surgery, radiotherapy, and chemotherapy, mainly because of extensive infiltration of tumor cells into the adjacent normal tissue. Thus, the evaluation of novel drugs in malignant glioma treatment requires sophisticated ex vivo models that approach the authentic interplay between tumor and host environment while avoiding extensive in vivo studies in animals. This paper describes the standardized setup of an organotypic brain tissue slice tandem-culture system, comprising of normal brain tissue from adult mice and tumor tissue from human glioblastoma xenografts, and explore its utility for assessing inhibitory effects of test drugs. The microscopic analysis of vertical sections of the slice tandem-cultures allows for the simultaneous assessment of (i) the invasive potential of single cells or cell aggregates and (ii) the space occupying growth of the bulk tumor mass, both contributing to malignant tumor progression. The comparison of tissue slice co-cultures with spheroids vs. tissue slice tandem-cultures using tumor xenograft slices demonstrates advantages of the xenograft tandem approach. The direct and facile application of test drugs is shown to exert inhibitory effects on bulk tumor growth and/or tumor cell invasion, and allows their precise quantitation. In conclusion, we describe a straightforward ex vivo system mimicking the in vivo situation of the tumor mass and the normal brain in GBM patients. It reduces animal studies and allows for the direct and reproducible application of test drugs and the precise quantitation of their effects on the bulk tumor mass and on the tumor’s invasive properties
In this paper we present a new approach to deterministic modelling of COVID-19 epidemic. Our model dynamics is expressed by a single prognostic variable which satisfies an integro-differential equation. All unknown parameters are described with a single, time-dependent variable R(t). We show that our model has similarities to classic compartmental models, such as SIR, and that the variable R(t) can be interpreted as a generalized effective reproduction number. The advantages of our approach are the simplicity of having only one equation, the numerical stability due to an integral formulation and the reliability since the model is formulated in terms of the most trustable statistical data variable: the number of cumulative diagnosed positive cases of COVID-19. Once this dynamic variable is calculated, other non-dynamic variables, such as the number of heavy cases (hospital beds), the number of intensive-care cases (ICUs) and the fatalities, can be derived from it using a similarly stable, integral approach. The formulation with a single equation allows us to calculate from real data the values of the sample effective reproduction number, which can then be fitted. Extrapolated values of R(t) can be used in the model to make reliable forecasts, though under the assumption that measures for reducing infections are maintained. We have applied our model to more than 15 countries and the ongoing results are available on a web-based platform [1]. In this paper, we focus on the data for two exemplary countries, Italy and Germany, and show that the model is capable of reproducing the course of the epidemic in the past and forecasting its course for a period of four to five weeks with a reasonable numerical stability.
Type 1 diabetes (T1D) is mainly precipitated by the destruction of insulin-producing β-cells in the pancreatic islets of Langerhans by autoaggressive T cells. The etiology of the disease is still not clear, but besides genetic predisposition the exposure to environmental triggers seems to play a major role. Virus infection of islets has been demonstrated in biopsies of T1D patients, but there is still no firm proof that such an infection indeed results in islet-specific autoimmunity. However, virus infection results in a local inflammation with expression of inflammatory factors, such as cytokines and chemokines that attract and activate immune cells, including potential autoreactive T cells. Many chemokines have been found to be elevated in the serum and expressed by islet cells of T1D patients. In mouse models, it has been demonstrated that β-cells express chemokines involved in the initial recruitment of immune cells to the islets. The bulk load of chemokines is however released by the infiltrating immune cells that also express multiple chemokine receptors. The result is a mutual attraction of antigen-presenting cells and effector immune cells in the local islet microenvironment. Although there is a considerable redundancy within the chemokine ligand-receptor network, a few chemokines, such as CXCL10, seem to play a key role in the T1D pathogenesis. Studies with neutralizing antibodies and investigations in chemokine-deficient mice demonstrated that interfering with certain chemokine ligand-receptor axes might also ameliorate human T1D. However, one important aspect of such a treatment is the time of administration. Blockade of the recruitment of immune cells to the site of autoimmune destruction might not be effective when the disease process is already ongoing. By that time, autoaggressive cells have already arrived in the islet microenvironment and a blockade of migration might even hold them in place leading to accelerated destruction. Thus, an anti-chemokine therapy makes most sense in situations where the cells have not yet migrated to the islets. Such situations include treatment of patients at risk already carrying islet-antigen autoantibodies but are not yet diabetic, islet transplantation recipients, and patients that have undergone a T cell reset as occurring after anti-CD3 antibody treatment.