Refine
Document Type
- Article (6)
Has Fulltext
- yes (6)
Is part of the Bibliography
- no (6)
Keywords
- COVID-19 (3)
- SARS-CoV-2 (2)
- CD271 (1)
- Course evaluation (1)
- Digitalisierung (1)
- Digitization (1)
- Distance learning (1)
- Distanzunterricht (1)
- FFP3 respirator (1)
- HNSCC (1)
Institute
- Medizin (6)
Background: Due to the coronavirus disease 2019 (COVID-19) pandemic, interventions in the upper airways are considered high-risk procedures for otolaryngologists and their colleagues. The purpose of this study was to evaluate limitations in hearing and communication when using a powered air-purifying respirator (PAPR) system to protect against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) transmission and to assess the benefit of a headset. Methods: Acoustic properties of the PAPR system were measured using a head and torso simulator. Audiological tests (tone audiometry, Freiburg speech test, Oldenburg sentence test (OLSA)) were performed in normal-hearing subjects (n = 10) to assess hearing with PAPR. The audiological test setup also included simulation of conditions in which the target speaker used either a PAPR, a filtering face piece (FFP) 3 respirator, or a surgical face mask. Results: Audiological measurements revealed that sound insulation by the PAPR headtop and noise, generated by the blower-assisted respiratory protection system, resulted in significantly deteriorated hearing thresholds (4.0 ± 7.2 dB hearing level (HL) vs. 49.2 ± 11.0
One challenge of squamous cell carcinoma of the head and neck (SCCHN) chemotherapy is a small percentage of tumor cells that arrest in the G0 phase of the cell cycle and are thus not affected by chemotherapy. This could be one reason for tumor recurrence at a later date. The recruitment of these G0-arresting cells into the active cell cycle and thus, proliferation, may increase the efficacy of chemotherapeutic agents. The aim of this study was to investigate whether stimulation with recombinant epidermal growth factor (EGF) or serotonin leads to an increased tumor cell proliferation in xenografts. Detroit 562 cells were injected into NMRI-Foxn1nu mice. Treatment was performed with 15 µg murine or human EGF, or 200 µg serotonin. The control mice were treated with Lactated Ringer's solution (5 mice/group). Tumor size was measured on days 4, 8 and 12 after tumor cell injection. The EGF stimulated mice showed a significantly higher tumor growth compared to the serotonin-stimulated mice and the untreated controls. In the present study, we show that it is possible to stimulate tumor cells in xenografts by EGF and thus, enhance cell proliferation, resulting in a higher tumor growth compared to the untreated control group. In our future investigations, we plan to include a higher number of mice, an adjustment of the EGF dosage and cell subanalysis, considering the heterogeneity of SCCHN tumors.
Hintergrund und Fragestellung: Die Severe acute respiratory syndrome coronavirus type 2(SARS-CoV-2)-Pandemie hat die Ausbildung von Medizinstudierenden grundlegend verändert. Die Notwendigkeit von Kontaktbeschränkungen und die damit einhergehende Forderung nach Distanzunterricht hat dazu geführt, dass innerhalb kurzer Zeit digitale Lehrformate umgesetzt werden mussten. Ziel dieser Arbeit war die Auswertung der studentischen Evaluationsergebnisse für virtuellen Unterricht im Fach Hals-Nasen-Ohren-Heilkunde während der SARS-CoV-2-Pandemie und ein Vergleich mit den zuvor erhobenen Evaluationsergebnissen unter Präsenzbedingungen.
Material und Methoden: Untersucht wurden die Evaluationsergebnisse für die Blockpraktika im Wintersemester 2020/21 und im Sommersemester 2021, die in einem virtuellen Format mit kurzer Präsenzphase durchgeführt wurden, sowie die der komplett im konventionellen Präsenzformat durchgeführten Praktika von Sommersemester 2018 bis Wintersemester 2019/20. Die anonyme Befragung der Studierenden bezog sich auf verschiedene Aspekte der Lehrveranstaltung, wie z. B. Organisation, Didaktik und Lernatmosphäre.
Ergebnisse: Von 16 abgefragten Kategorien zeigten 14 (87,5%) signifikant bessere Evaluationsergebnisse für die virtuellen Praktika verglichen mit den zuvor im Präsenzformat durchgeführten Praktika. Diese sehr positive Bewertung des digitalen Lehrangebots zeigte im Pandemieverlauf über die Dauer von zwei Semestern keine signifikante Änderung.
Schlussfolgerung: Die vorliegenden Daten belegen die hohe Akzeptanz eines digitalen Lehrangebots im Fach HNO-Heilkunde für Studierende. Auch wenn unerlässliche Bestandteile der ärztlichen Ausbildung, wie der Unterricht am Patienten und das Erlernen klinisch-praktischer Fertigkeiten, weiterhin nur im Präsenzformat realisiert werden können, legen die Ergebnisse nahe, dass digitale Elemente auch nach der SARS-CoV-2-Pandemie eine Rolle im Medizinstudium spielen könnten.
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and often has a poor prognosis. The present study investigated the role of the low affinity nerve growth factor receptor CD271 as a putative therapy target in HNSCC. Neurotrophins that bind to CD271 also have a high affinity for the tropomyosin receptor kinase family (Trk), consisting of TrkA, TrkB, and TrkC, which must also be considered in addition to CD271. A retrospective study and functional in vitro cell line tests (migration assay and cell sorting) were conducted in order to evaluate the relevance of CD271 expression alone and with regard to Trk expression. CD271 and Trks were heterogeneously expressed in human HNSCC. The vast majority of tumors exhibited CD271 and TrkA, whereas only half of the tumors expressed TrkB and TrkC. High expression of CD271-positive cells predicted a bad clinical outcome of patients with HNSCC and was associated with distant metastases. However, the human carcinomas that also expressed TrkC had a reduced correlation with distant metastases and better survival rates. In vitro, CD271 expression marked a subpopulation with higher proliferation rates, but proliferation was lower in tumor cells that co-expressed CD271 and TrkC. The CD271 inhibitor LM11A 31 suppressed cell motility in vitro. However, neither TrkA nor TrkB expression were linked to prognosis or cell proliferation. We conclude that CD271 is a promising candidate that provides prognostic information for HNSCC and could be a putative target for HNSCC treatment.
Molecular biology of hearing
(2012)
The inner ear is our most sensitive sensory organ and can be subdivided into three functional units: organ of Corti, stria vascularis and spiral ganglion. The appropriate stimulus for the organ of hearing is sound, which travels through the external auditory canal to the middle ear where it is transmitted to the inner ear. The inner ear houses the hair cells, the sensory cells of hearing. The inner hair cells are capable of mechanotransduction, the transformation of mechanical force into an electrical signal, which is the basic principle of hearing. The stria vascularis generates the endocochlear potential and maintains the ionic homeostasis of the endolymph. The dendrites of the spiral ganglion form synaptic contacts with the hair cells. The spiral ganglion is composed of neurons that transmit the electrical signals from the cochlea to the central nervous system. In recent years there has been significant progress in research on the molecular basis of hearing. An increasing number of genes and proteins related to hearing are being identified and characterized. The growing knowledge of these genes contributes not only to greater appreciation of the mechanism of hearing but also to a deeper understanding of the molecular basis of hereditary hearing loss. This basic research is a prerequisite for the development of molecular diagnostics and novel therapies for hearing loss.
Purpose: Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) replicates predominantly in the upper respiratory tract and is primarily transmitted by droplets and aerosols. Taking the medical history for typical COVID-19 symptoms and PCR-based SARS-CoV-2 testing have become established as screening procedures. The aim of this work was to describe the clinical appearance of SARS-CoV-2-PCR positive patients and to determine the SARS-CoV-2 contact risk for health care workers (HCW).
Methods: The retrospective study included n = 2283 SARS-CoV-2 PCR tests from n = 1725 patients with otorhinolaryngological (ORL) diseases performed from March to November 2020 prior to inpatient treatment. In addition, demographic data and medical history were assessed.
Results: n = 13 PCR tests (0.6%) were positive for SARS-CoV-2 RNA. The positive rate showed a significant increase during the observation period (p < 0.01). None of the patients had clinical symptoms that led to a suspected diagnosis of COVID-19 before PCR testing. The patients were either asymptomatic (n = 4) or had symptoms that were interpreted as symptoms typical of the ORL disease or secondary diagnoses (n = 9).
Conclusion: The identification of SARS-CoV-2-positive patients is a considerable challenge in clinical practice. Our findings illustrate that taking a medical history alone is of limited value and cannot replace molecular SARS-CoV-2 testing, especially for patients with ORL diseases. Our data also demonstrate that there is a high probability of contact with SARS-CoV-2-positive patients in everyday clinical practice, so that the use of personal protective equipment, even in apparently “routine cases”, is highly recommended.
