Background: Various symptoms have been associated with COVID-19, but little is known about the impacts of COVID-19 on the sensory system, risk factors, and the duration of symptoms. This study assesses olfactory, gustatory, hearing, and vestibular systems after COVID-19. Methods: This cross-sectional, single-center study involved 50 patients one to six months after COVID-19 and reports their patient records and the extent, onset, and duration of olfactory, gustatory, hearing, and balance disorders using questionnaires during and after COVID-19. Sensory symptoms were objectively studied using the following clinical tests after COVID-19 Sniffin’ Sticks, taste tests, tone/speech audiometry, and video head impulse test. Results: Post-COVID-19-patients were suffering from olfactory and gustatory impairment for up to six months. According to the Dizziness Handicap Inventory, balance disorders were less noticed: Overall, about 40% of the patients during COVID-19 and nearly all patients recovered within six months. After COVID-19, clinical tests revealed that 75% were suffering from hyposomnia/anosmia, and 20% of all patients reported mild hypogeusia for up to six months. Vestibular disorders and hearing impairment rarely/did not occur. Females were significantly more affected by sensory impairments than males. Conclusions: COVID-19 particularly caused olfactory and gustatory impairment; balance disorders were present too; vestibular and auditory symptoms were negligible.

Background: Despite extensive research into new treatment options, the prognosis for head and neck squamous cell carcinoma remains poor. Platelet-derived growth factor (PDGF) is up-regulated in HNSCC and expression levels decrease after surgery, suggesting its role in tumour development. The influence of HPV on the PDGF/PDGF receptor (PDGFR) pathway remains unclear. In this study, we investigated the effect of small-molecule tyrosine kinase inhibitors (TKIs) on the expression of PDGF and its receptor in vitro using squamous cancer cell lines with different human papillomavirus 16 (HPV16) status. Materials and Methods: Two human HPV16-negative cell lines (UMSCC-11A/-14C) and one HPV16-positive cell line (CERV196) were used. Tumour cells were incubated with 20 μmol/l of TKIs nilotinib, dasatinib, afatinib, gefitinib and erlotinib for 24-96 h. Cell proliferation was assessed via proliferation assay and protein concentrations of PDGF-AA and BB and PDGFRα and -β via sandwich enzyme-linked immunosorbent assay. For statistical analysis, the results were compared with those from an untreated negative control. Results: PDGF-AA/BB and PDGFRα/-β were detected in all three tested cell lines. The addition of TKI led to a significant (p<0.05) decrease of PDGF/PDGFR at different time points and cell lines. The strongest effects were seen for the expression of PDGF-AA, which was consistently inhibited by most drugs. The effects of the TKI were independent of the HPV status. Conclusion: Proteins of this pathway can effectively be inhibited by small molecule TKIs. PDGF-AA seems to be a promising target for future studies with selective TKIs.

Nasal septum defects can currently only be reconstructed using autologous cartilage grafts. In this study, we examine the reconstruction of septal cartilage defects in a rabbit model using porcine decellularized nasal septal cartilage (DNSC) functionalized with recombinant platelet-derived growth factor-BB (PDFG-BB). The supportive function of the transplanted DNSC was estimated by the degree of septum deviation and shrinkage using magnetic resonance imaging (MRI). The biocompatibility of the transplanted scaffolds was evaluated by histology according to international standards. A study group with an autologous septal transplant was used as a reference. In situ regeneration of cartilage defects was assessed by histological evaluation 4 and 16 weeks following DNSC transplantation. A study group with non-functionalized DNSC was introduced for estimation of the effects of PDFG-BB functionalization. DNSC scaffolds provided sufficient structural support to the nasal septum, with no significant shrinkage or septal deviations as evaluated by the MRI. Biocompatibility analysis after 4 weeks revealed an increased inflammatory reaction of the surrounding tissue in response to DNSC as compared to the autologous transplants. The inflammatory reaction was, however, significantly attenuated after 16 weeks in the PDGF-BB group whereas only a slight improvement of the biocompatibility score was observed in the untreated group. In situ regeneration of septal cartilage, as evidenced by the degradation of the DNSC matrix and production of neocartilage, was observed in both experimental groups after 16 weeks but was more pronounced in the PDFG-BB group. Overall, DNSC provided structural support to the nasal septum and stimulated in situ regeneration of the cartilage tissue. Furthermore, PDFG-BB augmented the regenerative potential of DNSC and enhanced the healing process, as demonstrated by reduced inflammation after 16 weeks.

The gold standard of auricular reconstruction involves manual graft assembly from autologous costal cartilage. The intervention may require multiple surgical procedures and lead to donor‐site morbidity, while the outcome is highly dependent on individual surgical skills. A tissue engineering approach provides the means to produce cartilage grafts of a defined shape from autologous chondrocytes. The use of autologous cells minimizes the risk of host immune response; however, factors such as biomaterial compatibility and in vitro maturation of the tissue‐engineered (TE) cartilage may influence the engraftment and shape‐stability of TE implants. Here, this work tests the biocompatibility of bioprinted autologous cartilage constructs in a rabbit model. The TE cartilage is produced by embedding autologous auricular chondrocytes into hyaluronan transglutaminase (HATG) based bioink, previously shown to support chondrogenesis in human auricular chondrocytes in vitro and in immunocompromised xenotransplantation models in vivo. A drastic softening and loss of cartilage markers, such as sulfated glycosaminoglycans (GAGs) and collagen type II are observed. Furthermore, fibrous encapsulation and partial degradation of the transplanted constructs are indicative of a strong host immune response to the autologous TE cartilage. The current study thus illustrates the crucial importance of immunocompetent autologous animal models for the evaluation of TE cartilage function and compatibility.

Background: Head and neck squamous cell carcinoma (HNSCC) is a globally significant disease with poor survival outcomes. Immune checkpoint inhibitors (ICIs) such as pembrolizumab and nivolumab have improved treatment paradigms, yet their real‐world efficacy and the factors influencing treatment outcomes remain underexplored. Aims: This study aimed to evaluate real‐world outcomes of pembrolizumab and nivolumab therapy in patients with HNSCC and to identify clinical and laboratory factors associated with overall survival (OS), progression‐free survival (PFS), and objective response rate (ORR). Methods and Results: We conducted a retrospective analysis of 45 HNSCC patients treated with pembrolizumab or nivolumab at the University Medical Center Mannheim. Patient‐specific factors, including tumor characteristics, PD‐L1 expression, and laboratory parameters, were assessed using Kaplan–Meier estimation, log‐rank tests, and multivariate regression models. The median OS and PFS were 10.4 months and 7.4 months, respectively, with an ORR of 22%. A tumor proportion score (TPS) ≥ 50% and absence of smoking or alcohol abuse significantly improved ORR, while female sex, high neutrophil‐to‐lymphocyte ratio (NLR), and elevated leukocyte counts were associated with inferior OS and PFS. Real‐world outcomes largely aligned with the pivotal trials Keynote‐048 and CheckMate 141. Conclusion: This study underscores the predictive value of TPS and patient lifestyle factors in ICI treatment for HNSCC. The findings also highlight sex‐specific differences, as well as NLR and leukocyte count as potential prognostic factors. Larger, more diverse cohorts are needed to confirm these results and refine patient selection strategies.

Background: Targeted therapies in the treatment of head and neck squamous cell carcinoma (HNSCC) are subject to extensive research. Different mutations of genes belonging to the fibroblast growth factor (FGF) family have been detected in HNSCC. In this study, we examined the expression of FGF1 and FGF2 after treatment with small-molecule tyrosine kinase inhibitors (TKIs) and an inhibitor of mechanistic target of rapamycin (mTOR) in vitro using human papillomavirus (HPV)-positive and -negative SCC lines. Materials and Methods: Cells of two human HPV-negative cell lines (UMSCC-11A/-14C) and one HPV-positive cell line (CERV196) were incubated with 20 μmol/l of erlotinib, gefitinib, nilotinib, dasatinib, or everolimus for 24-96 h. Cell proliferation was assessed by proliferation assay and the protein concentrations of FGF1 and FGF2 by sandwich enzyme-linked immunosorbent assay. For statistical analysis, the results were compared with those for untreated HPV-negative SCC cells. Results: FGF1 and FGF2 were detected in all three tested cell lines. The tested TKIs significantly (p<0.05 reduced) FGF1 expression in the UMSCC-11A cell line within the first 24 h. At later time points, the tested TKIs and everolimus significantly (p<0.05) increased FGF1 and FGF2 expression in HPV-negative and -positive cancer cell lines. The effect was stronger in the HPV-positive cell line. Conclusion: Alterations in FGF signalling are considered to be relevant drivers of tumourigenesis in some HNSCCs. Our results show that the expression of FGF1 and -2 can be influenced effectively by small-molecule TKIs and everolimus. Based on our data, future research should include combinations of specific FGF inhibitors, mTOR inhibitors and other TKIs in the treatment of HNSCC and research on FGF-mediated drug escape mechanisms.