Gut microbiota-tryptophan metabolism-GLP-1 axis participates in β-cell regeneration induced by dapagliflozin

Sodium-glucose co-transporter 2 (SGLT2) inhibitor, an efficacious anti-diabetic agent, which has cardiovascular and renal benefits, can promote pancreatic β-cell regeneration in type 2 diabetic mice. However, the underlying mechanism remains unclear. In this study, we aimed to use multi-omics to identify the mediators involved in β-cell regeneration induced by dapagliflozin. We showed that dapagliflozin lowered blood glucose level, upregulated plasma insulin level, and increased islet area in db/db mice. Dapagliflozin reshaped gut microbiota, and modulated microbiotic and plasmatic metabolites related to tryptophan metabolism, especially L-tryptophan, in the diabetic mice. Notably, L-tryptophan upregulated the mRNA level of GLP-1 production-related genes (Gcg and Pcsk1) expression and promoted GLP-1 secretion in cultured mouse intestinal L-cells, and it increased supernatant insulin level in primary human islets, which was eliminated by GPR142 antagonist. Transplantation of fecal microbiota from dapagliflozin-treated mice, supplementation of L-tryptophan or treatment with dapagliflozin upregulated L-tryptophan, GLP-1, and insulin or C-peptide level, and promoted β-cell regeneration in db/db mice. Addition of exendin 9-39, a GLP-1 receptor (GLP-1R) antagonist, or pancreatic Glp1r knockout diminished these beneficial effects. In summary, treatment with dapagliflozin in type 2 diabetic mice promotes β-cell regeneration by upregulating GLP-1 production, which is mediated via gut microbiota and tryptophan metabolism.

Prospects for online adaptive radiation therapy (ART) for head and neck cancer

BACKGROUND

The aim of the present study is to examine the impact of kV-CBCT-based online adaptive radiation therapy (ART) on dosimetric parameters in comparison to image-guided-radiotherapy (IGRT) in consecutive patients with tumors in the head and neck region from a prospective registry.

METHODS

The study comprises all consecutive patients with tumors in the head and neck area who were treated with kV-CBCT-based online ART or IGRT-modus at the linear-accelerator ETHOS™. As a measure of effectiveness, the equivalent-uniform-dose was calculated for the CTV (EUDCTV) and organs-at-risk (EUDOAR) and normalized to the prescribed dose. As an important determinant for the need of ART the interfractional shifts of anatomic landmarks related to the tongue were analyzed and compared to the intrafractional shifts. The latter determine the performance of the adapted dose distribution on the verification CBCT2 postadaptation.

RESULTS

Altogether 59 consecutive patients with tumors in the head-and-neck-area were treated from 01.12.2021 to 31.01.2023. Ten of all 59 patients (10/59; 16.9%) received at least one phase within a treatment course with ART. Of 46 fractions in the adaptive mode, irradiation was conducted in 65.2% of fractions with the adaptive-plan, the scheduled-plan in the remaining. The dispersion of the distributions of EUDCTV-values from the 46 dose fractions differed significantly between the scheduled and adaptive plans (Ansari-Bradley-Test, p = 0.0158). Thus, the 2.5th percentile of the EUDCTV-values by the adaptive plans amounted 97.1% (95% CI 96.6-99.5%) and by the scheduled plans 78.1% (95% CI 61.8-88.7%). While the EUDCTV for the accumulated dose distributions stayed above 95% at PTV-margins of ≥ 3 mm for all 8 analyzed treatment phases the scheduled plans did for margins ≥ 5 mm. The intrafractional anatomic shifts of all 8 measured anatomic landmarks were smaller than the interfractional with overall median values of 8.5 mm and 5.5 mm (p < 0.0001 for five and p < 0.05 for all parameters, pairwise comparisons, signed-rank-test). The EUDOAR-values for the larynx and the parotid gland were significantly lower for the adaptive compared with the scheduled plans (Wilcoxon-test, p < 0.001).

CONCLUSIONS

The mobile tongue and tongue base showed considerable interfractional variations. While PTV-margins of 5 mm were sufficient for IGRT, ART showed the potential of decreasing PTV-margins and spare dose to the organs-at-risk.

Abdominal ultrasound in head and neck squamous cell carcinoma staging: yes or no?

PURPOSE

Abdominal ultrasound is a diagnostic staging procedure for distant metastases in head and neck squamous cell carcinoma (HNSCC). However, currently performed abdominal staging procedures do not follow consistent standards. Therefore, this retrospective study on 498 patients aimed at investigating on abdominal ultrasound as a staging procedure in HNSCC.

MATERIALS AND METHODS

A retrospective analysis of 498 head and neck cancer patients treated in our Department of Head and Neck Surgery between 2008 and 2015 was performed. Disease-related data were collected over a mean follow-up time of 30.3 months, and results of abdominal ultrasound were analyzed.

RESULTS

426 patients received abdominal ultrasound as a staging procedure. 7% (29) were suspicious for metastases. In 19 cases (66%), the detected abnormalities were masses of the liver. In four patients, abdominal metastases were confirmed at the time of initial diagnosis. 16 patients developed abdominal metastases in the course of the disease (on average 623 days after initial diagnosis). 19 out of 20 patients with abdominal metastases had an N2/N3 cervical lymph node status. In this study, the negative predictive value of abdominal ultrasound for HNSCC staging was 99.03%, while the positive predictive value yielded 5.88% (N2/N3-patients).

CONCLUSION

Only in patients with locally advanced lymph-node-status (N2/N3), abdominal ultrasound can be useful as a staging investigation to exclude abdominal metastasis in HNSCC patients. For N0/N1 patients, abdominal ultrasound might be dispensed. Of note, in case of a positive result, further diagnostic procedures are mandatory.

Pancreatic alpha cell glucagon-liver FGF21 axis regulates beta cell regeneration in a mouse model of type 2 diabetes

AIMS/HYPOTHESIS

Glucagon receptor (GCGR) antagonism ameliorates hyperglycaemia and promotes beta cell regeneration in mouse models of type 2 diabetes. However, the underlying mechanisms remain unclear. The present study aimed to investigate the mechanism of beta cell regeneration induced by GCGR antagonism in mice.

METHODS

The db/db mice and high-fat diet (HFD)+streptozotocin (STZ)-induced mice with type 2 diabetes were treated with antagonistic GCGR monoclonal antibody (mAb), and the metabolic variables and islet cell quantification were evaluated. Plasma cytokine array and liver RNA sequencing data were used to screen possible mediators, including fibroblast growth factor 21 (FGF21). ELISA, quantitative RT-PCR and western blot were applied to verify FGF21 change. Blockage of FGF21 signalling by FGF21-neutralising antibody (nAb) was used to clarify whether FGF21 was involved in the effects of GCGR mAb on the expression of beta cell identity-related genes under plasma-conditional culture and hepatocyte co-culture conditions. FGF21 nAb-treated db/db mice, systemic Fgf21-knockout (Fgf21^-/-) diabetic mice and hepatocyte-specific Fgf21-knockout (Fgf21^Hep-/-) diabetic mice were used to reveal the involvement of FGF21 in beta cell regeneration. A BrdU tracing study was used to analyse beta cell proliferation in diabetic mice treated with GCGR mAb.

RESULTS

GCGR mAb treatment improved blood glucose control, and increased islet number (db/db 1.6±0.1 vs 0.8±0.1 per mm², p<0.001; HFD+STZ 1.2±0.1 vs 0.5±0.1 per mm², p<0.01) and area (db/db 2.5±0.2 vs 1.2±0.2%, p<0.001; HFD+STZ 1.0±0.1 vs 0.3±0.1%, p<0.01) in diabetic mice. The plasma cytokine array and liver RNA sequencing data showed that FGF21 levels in plasma and liver were upregulated by GCGR antagonism. The GCGR mAb induced upregulation of plasma FGF21 levels (db/db 661.5±40.0 vs 466.2±55.7 pg/ml, p<0.05; HFD+STZ 877.0±106.8 vs 445.5±54.0 pg/ml, p<0.05) and the liver levels of Fgf21 mRNA (db/db 3.2±0.5 vs 1.8±0.1, p<0.05; HFD+STZ 2.0±0.3 vs 1.0±0.2, p<0.05) and protein (db/db 2.0±0.2 vs 1.4±0.1, p<0.05; HFD+STZ 1.6±0.1 vs 1.0±0.1, p<0.01). Exposure to plasma or hepatocytes from the GCGR mAb-treated mice upregulated the mRNA levels of characteristic genes associated with beta cell identity in cultured mouse islets and a beta cell line, and blockage of FGF21 activity by an FGF21 nAb diminished this upregulation. Notably, the effects of increased beta cell number induced by GCGR mAb were attenuated in FGF21 nAb-treated db/db mice, Fgf21^-/- diabetic mice and Fgf21^Hep-/- diabetic mice. Moreover, GCGR mAb treatment enhanced beta cell proliferation in the two groups of diabetic mice, and this effect was weakened in Fgf21^-/- and Fgf21^Hep-/- mice.

CONCLUSIONS/INTERPRETATION

Our findings demonstrate that liver-derived FGF21 is involved in the GCGR antagonism-induced beta cell regeneration in a mouse model of type 2 diabetes.

A semiparametric model for between-subject attributes: Applications to beta-diversity of microbiome data

The human microbiome plays an important role in our health and identifying factors associated with microbiome composition provides insights into inherent disease mechanisms. By amplifying and sequencing the marker genes in high-throughput sequencing, with highly similar sequences binned together, we obtain operational taxonomic units (OTUs) profiles for each subject. Due to the high-dimensionality and nonnormality features of the OTUs, the measure of diversity is introduced as a summarization at the microbial community level, including the distance-based beta-diversity between individuals. Analyses of such between-subject attributes are not amenable to the predominant within-subject-based statistical paradigm, such as t-tests and linear regression. In this paper, we propose a new approach to model beta-diversity as a response within a regression setting by utilizing the functional response models (FRMs), a class of semiparametric models for between- as well as within-subject attributes. The new approach not only addresses limitations of current methods for beta-diversity with cross-sectional data, but also provides a premise for extending the approach to longitudinal and other clustered data in the future. The proposed approach is illustrated with both real and simulated data.

Pro-α-cell-derived β-cells contribute to β-cell neogenesis induced by antagonistic glucagon receptor antibody in type 2 diabetic mice

The deficiency of pancreatic β-cells is the key pathogenesis of diabetes, while glucagon-secreting α-cells are another player in the development of diabetes. Here, we aimed to investigate the effects of glucagon receptor (GCGR) antagonism on β-cell neogenesis in type 2 diabetic (T2D) mice and explore the origins of the neogenic β-cells. We showed that GCGR monoclonal antibody (mAb) elevated plasma insulin level and increased β-cell mass in T2D mice. By using α-cell lineage-tracing (glucagon-cre-β-gal) mice and inducible Ngn3⁺ pancreatic endocrine progenitor lineage-tracing (Ngn3-CreERT2-tdTomato) mice, we found that GCGR mAb treatment promoted α-cell regression to progenitors, and induced Ngn3⁺ progenitor reactivation and differentiation toward β-cells. Besides, GCGR mAb upregulated the expression levels of β-cell regeneration-associated genes and promoted insulin secretion in primary mouse islets, indicative of a direct effect on β-cell identity. Our findings suggest that GCGR antagonism not only increases insulin secretion but also promotes pro-α-cell-derived β-cell neogenesis in T2D mice.

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Blockage of α-cell-derived glucagon promotes β-cell regeneration in situ in type 2 diabetic (T2D) mice

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Glucagon receptor (GCGR) mAb induces the trans-differentiation of α-cells to β-cells

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GCGR mAb promotes α-cell regression to pancreatic endocrine progenitors

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GCGR mAb induces Ngn3⁺ progenitor reactivation and differentiation toward β-cells

Detection accuracy of soft tissue complications during remote cochlear implant follow-up

PURPOSE

After cochlear implantation (CI), long-term follow-up is obligatory. Remote-care options which provide a standard of care comparable to in-person consultations, could be an attractive addition to a cochlear implant centre's portfolio. The aim of this study was to evaluate the accuracy of photographs of the skin covering the implant to reliably detect skin irritations or soft tissue complications.

METHODS

During routine follow-up consultations, 109 CI patients were examined in person and asked to take a photograph of the skin covering the implant using their smartphones. Photographs were digitally and remotely evaluated by two CI physicians who were blinded to the findings during the in-person examination.

RESULTS

In nine cases, skin abnormalities were detected by the CI physician upon in-person examination, seven of which required immediate treatment. Both digital evaluators reliably detected all treatment-requiring conditions. Overall, more skin irritations were suspected digitally compared to in-person examination. Without additional information from the patients' medical record, sensitivity was 100% and specificity was 63%; with additional information provided, sensitivity was 100%, and specificity increased to 65.3%.

CONCLUSION

Digital photographic assessment of the skin covering the implant is a highly sensitive method to detect skin irritations and could reduce the number of necessary in-person consultations.

Vertebral osteomyelitis is characterised by increased RANK/OPG and RANKL/OPG expression ratios in vertebral bodies and intervertebral discs

Vertebral osteomyelitis (VO) is an infection of the spine mainly caused by bacterial pathogens. The pathogenesis leading to destruction of intervertebral discs (IVDs) and adjacent vertebral bodies (VBs) is poorly described. The present study aimed at investigating the connection between infection and bone/disc metabolism in VO patients. 14 patients with VO (infection group) and 14 patients with burst fractures of the spine (fracture group; control) were included prospectively. Tissue biopsies from affected IVDs and adjacent VBs were analysed by RT-qPCR for mRNA-expression levels of 18 target genes including chemokines, adipokines and genes involved in bone metabolism. Most importantly, the receptor activator of NF-κB/osteoprotegerin (RANK/OPG) expression ratio was drastically elevated in both VBs and IVDs of the infection group. In parallel, expression of genes of the prostaglandin-E2-dependent prostanoid system was induced. Such genes regulate tissue degradation processes via the triad OPG/RANK/RANKL as well as via the chemokines IL-8 and CCL-20, whose expression was also found to be increased upon infection. The gene expression of the adipokine leptin, which promotes inflammatory tissue degradation, was higher in IVD tissue of the infection group, whereas the transcription of omentin and resistin genes, whose functions are largely unknown in the context of infectious diseases, was lower in infected VBs. In summary, similar expression patterns of pro-inflammatory cytokines and pro-osteoclastogenic factors were identified in VBs and IVDs of patients suffering from VO. This suggests that common immuno-metabolic pathways are involved in the mechanisms leading to tissue degradation in VBs and IVDs during VO.

Association between Thyroid Function and Prognosis of COVID-19: A Retrospective Observational Study

Background: Coronavirus disease 2019 (COVID-19) is a severe infectious illness. It has been reported that COVID-19 has an effect on thyroid function. However, the association between thyroid function and prognosis of COVID-19 is still unclear.Methods: This retrospective study included patients with COVID-19 admitted to Tongji Hospital in Wuhan from January 28 to April 4, 2020. Demographic, epidemiological, clinical, laboratory, treatment, and outcome data were collected from patients with laboratory-confirmed COVID-19. Patients without history of thyroid disease who had a thyroid function test at admission were enrolled in the final analysis. Risk factors of in-hospital death were explored using univariable and multivariable Cox regression analyses. Survival differences were assessed with Kaplan-Meier curves and log-rank test.Results: A total of 127 patients were included in this study, with 116 survivors and 11 non-survivors. The serum levels of thyroid stimulating hormone (TSH) [0.8 (0.5-1.7) vs. 1.9 (1.0-3.1) μIU/mL, P = .031] and free triiodothyronine (FT₃) [2.9 (2.8-3.1) vs. 4.2 (3.5-4.7) pmol/L, P < .001] were lower in non-survivors than in survivors, and a low FT₃ state (defined as FT₃ < 3.1 pmol/L) at admission accounted for a higher proportion in non-survivors than in survivors (72.7% vs. 11.2%, P < .001). Univariate Cox regression analysis showed that FT₃ level (HR 0.213, 95% CI: 0.101-0.451, P < .001) and the low FT₃ state (HR 14.607, 95% CI: 3.873-55.081, P < .001) were negatively and positively associated with the risk of in-hospital death, respectively. Furthermore, multivariate Cox regression analysis revealed that a low FT₃ state was associated with an increased risk of in-hospital death after adjusting for confounding factors (HR 13.288, 95% CI: 1.089-162.110, P = .043). Moreover, Kaplan-Meier curves indicated a lower survival probability in COVID-19 patients with a low FT₃ status.Conclusion: Serum FT₃ level is lower in non-survivors among moderate-to-critical patients with COVID-19, and the low FT₃ state is associated with an increased risk of in-hospital mortality of COVID-19.

Artificial Intelligence-Based 3D Angiography for Visualization of Complex Cerebrovascular Pathologies

BACKGROUND AND PURPOSE

By means of artificial intelligence, 3D angiography is a novel postprocessing method for 3D imaging of cerebral vessels. Because 3D angiography does not require a mask run like the current standard 3D-DSA, it potentially offers a considerable reduction of the patient radiation dose. Our aim was an assessment of the diagnostic value of 3D angiography for visualization of cerebrovascular pathologies.

MATERIALS AND METHODS

3D-DSA data sets of cerebral aneurysms (n _CA = 10), AVMs (n _AVM = 10), and dural arteriovenous fistulas (dAVFs) (n _dAVF = 10) were reconstructed using both conventional and prototype software. Corresponding reconstructions have been analyzed by 2 neuroradiologists in a consensus reading in terms of image quality, injection vessel diameters (vessel diameter [VD] 1/2), vessel geometry index (VGI = VD1/VD2), and specific qualitative/quantitative parameters of AVMs (eg, location, nidus size, feeder, associated aneurysms, drainage, Spetzler-Martin score), dAVFs (eg, fistulous point, main feeder, diameter of the main feeder, drainage), and cerebral aneurysms (location, neck, size).

RESULTS

In total, 60 volumes have been successfully reconstructed with equivalent image quality. The specific qualitative/quantitative assessment of 3D angiography revealed nearly complete accordance with 3D-DSA in AVMs (eg, mean nidus size_{3D angiography/3D-DSA}= 19.9 [SD, 10.9]/20.2 [SD, 11.2] mm; r = 0.9, P = .001), dAVFs (eg, mean diameter of the main feeder_{3D angiography/3D-DSA}= 2.04 [SD, 0.65]/2.05 [SD, 0.63] mm; r = 0.9, P = .001), and cerebral aneurysms (eg, mean size_{3D angiography/3D-DSA}= 5.17 [SD, 3.4]/5.12 [SD, 3.3] mm; r = 0.9, P = .001). Assessment of the geometry of the injection vessel in 3D angiography data sets did not differ significantly from that of 3D-DSA (vessel geometry index_AVM: r = 0.84, P = .003; vessel geometry index_dAVF: r = 0.82, P = .003; vessel geometry index_CA: r = 0.84, P <.001).

CONCLUSIONS

In this study, the artificial intelligence-based 3D angiography was a reliable method for visualization of complex cerebrovascular pathologies and showed results comparable with those of 3D-DSA. Thus, 3D angiography is a promising postprocessing method that provides a significant reduction of the patient radiation dose.

[Perioperative medical prophylaxis of venous thromboembolic events in head and neck surgery : A retrospective study and recommendations]

BACKGROUND

In the authors' department, a newly implemented clinical algorithm for application of perioperative thrombosis prophylaxis in head and neck surgery recommends restrictive handling of anticoagulants. This retrospective study aims to evaluate the algorithm by comparing incidences of venous thromboembolic events (VTE) and surgical revisions due to postoperative hemorrhage.

MATERIALS AND METHODS

Perioperative incidences of deep vein thrombosis and pulmonary embolism as well as surgical revisions due to postoperative hemorrhage after head and neck surgery were determined based on all patients operated in the department over a period of 36 months. The incidences before (group I) and after (group II) implementation of the restrictive algorithm were compared.

RESULTS

A total of 9276 patients were included. The incidences of VTE (0.12%) and surgical revisions due to postoperative hemorrhage (1.4%) were low. Incidences of VTE were non-significantly higher in group II (0.16%) than in group I (0.08%; p > 0.45, chi-square-test). Case analysis revealed that this difference was not due to implementation of the restrictive algorithm. The incidence of surgical revision due to postoperative hemorrhage was identical in the two groups (1.4%).

CONCLUSION

After restricting the indication for thrombosis prophylaxis, the incidence of VTE or surgical revision due to postoperative hemorrhage did not change significantly. The provided clinical algorithm represents a low-risk and low-cost strategy of perioperative risk stratification.

Magnet dislocation following magnetic resonance imaging in cochlear implant users: Diagnostic pathways and managment

OBJECTIVES

Although modern cochlear implants (CIs) are approved for magnetic resonance imaging (MRIs) adverse events still occur with unacceptable frequency. Methods: In this retrospective study, magnet displacement due to MRIs was analysed. Relevant factors e.g. symptoms during MRI, diagnostics, surgical intervention following the diagnosis and possible subsequent damage were assessed.

RESULTS

16 patients were enclosed. All patients complained about pain while the scan was conducted. Computed tomography (CT) scans of the temporal bone or X-rays of the skull were performed to confirm diagnosis. Artefacts on CT scans delayed immediate diagnosis in some cases.

DISCUSSION

Despite various studies demonstrating the range of adverse events related to CIs following MRI, little information is available on diagnosis and radiologic recognition of magnet dislocation. In patients complaining about pain following an MRI scan an X-ray of the head should be performed immediately. Most adverse events occur in radiological centres without expertise in cochlear implants.

CONCLUSION

Comprehensive training of patients, surgeons and radiologists is the most efficient tool to prevent damage to the CI and the patient. X-ray of the skull is suggested to be used as the method of choice in imaging.

[Effects of the SARS-CoV‑2 pandemic on the otolaryngology university hospitals in the field of research, student teaching and specialist training]

Hintergrund

Ab Frühjahr 2020 kam es zur weltweiten Verbreitung von SARS-CoV‑2 mit der heute als erste Welle der Pandemie bezeichneten Phase ab März 2020. Diese resultierte an vielen Kliniken in Umstrukturierungen und Ressourcenverschiebungen. Ziel unserer Arbeit war die Erfassung der Auswirkungen der Pandemie auf die universitäre Hals-Nasen-Ohren(HNO)-Heilkunde für die Forschung, Lehre und Weiterbildung.

Material und Methoden

Die Direktorinnen und Direktoren der 39 Universitäts-HNO-Kliniken in Deutschland wurden mithilfe einer strukturierten Online-Befragung zu den Auswirkungen der Pandemie im Zeitraum von März bis April 2020 auf die Forschung, Lehre und die Weiterbildung befragt.

Ergebnisse

Alle 39 Direktorinnen und Direktoren beteiligten sich an der Umfrage. Hiervon gaben 74,4 % (29/39) an, dass es zu einer Verschlechterung ihrer Forschungstätigkeit infolge der Pandemie gekommen sei. Von 61,5 % (24/39) wurde berichtet, dass pandemiebezogene Forschungsaspekte aufgegriffen wurden. Von allen Kliniken wurde eine Einschränkung der Präsenzlehre berichtet und 97,5 % (38/39) führten neue digitale Lehrformate ein. Im Beobachtungszeitraum sahen 74,4 % der Klinikdirektoren die Weiterbildung der Assistenten nicht gefährdet.

Schlussfolgerung

Die Ergebnisse geben einen Einblick in die heterogenen Auswirkungen der Pandemie. Die kurzfristige Bearbeitung pandemiebezogener Forschungsthemen und die Einführung innovativer digitaler Konzepte für die studentische Lehre belegt eindrücklich das große innovative Potenzial und die schnelle Reaktionsfähigkeit der HNO-Universitätskliniken, um auch während der Pandemie ihre Aufgaben in der Forschung, Lehre und Weiterbildung bestmöglich zu erfüllen.

[Regional distribution of the cochlear implant (CI) centers in Germany]

The treatment of patients with severe hearing loss or deafness with a cochlear implant (CI) represents a standard in Germany today. However, there is hardly any data on the current number of clinical CI centers (CI clinics) and their geographical distribution. The patient self-help organization, German Cochlear Implant Society (DCIG), and the German Society for Otorhinolaryngology, Head and Neck Surgery (DGHNO-KHC) have therefore initiated a survey to determine the regional distribution, the range of services, the consideration of existing quality standards and cooperation with patient self-help organizations of the individual clinical CI centers.For this purpose, a total number of 170 ENT departments or their directors (37 professors and 133 chief physicians), respectively, were contacted by e-mail and provided with a questionnaire. The survey took place from October 2019 to February 2020.Of the 170 departments contacted, 71 (41.8 %) took part in the survey. Of these, 70 departments (98.6 %) confirmed to perform CI surgeries. Thus, 41.8 % of all clinics contacted reported to perform CI surgeries (70 of 170 clinics), while this information was not available from 99 clinics. All 70 clinical CI centers (100 %) reported to conduct CI surgeries on adults, 60 centers (85.7 %) also on children (< 18 years). 36 departments (51.4 %) reported that the total number of CI surgeries at their facility in 2018 was more than 50. In 64 departments (91.4 %), the recommendations of the DGHNO-KHC on CI care (according to the White Paper CI care 2018) were followed. A collaboration between the department and patient self-help organization was confirmed by 67 institutions (95.7 %). The geographical distribution of the clinical CI centers showed a heterogeneous distribution pattern between the individual federal states and also within the respective federal state.The work presented here is a first assessment of the situation with regard to the regional distribution of clinical CI centers in Germany. A clustering of CI centers was noticeable in metropolitan areas, sometimes with several facilities in one city. The predominant attention to quality-related aspects, such as the consideration of the DGHNO-KHC white paper and the cooperation with patient self-help, is gratifying. The limitations of the study result from limited participation in the survey (41.8 % of the contacted clinics).

Asymptomatic cerebral abscesses after pleuropulmonary Nocardia farcinica infection

We report the case of a 68-year-old man with long-term receipt of steroid therapy who was diagnosed with cerebral abscesses and pulmonary nocardiosis. This patient displayed only respiratory symptoms. Confirmation of Nocardia farcinica species was achieved by specific PCR sequencing of the 16S ribosome RNA in bronchoalveolar lavage cultures. Cerebral magnetic resonance imaging revealed abscesses. Antibiotic therapy with trimethoprim/sulfamethoxazole was prescribed given the results of susceptibility tests and was maintained for 12 months, with no evidence of relapse afterwards.

[Stimulatory and inhibitory signaling pathways of the T cell-APC interaction and the effect of TLR agonists on APCs]

BACKGROUND

CD8⁺ cells are key players in the identification and elimination of cancer cells. Cancers can escape an effective T cell response by inducing an exhausted cell state, which limits the cytotoxic capacity of the effector cells. Among other mechanisms, new checkpoint inhibitors reactivate exhausted, dysfunctional T cells. CD8⁺ T cells can eliminate tumor cells after presentation of tumor-specific antigens via antigen-presenting cells (APCs). APC-mediated tumor recognition is mainly stimulated by Toll-like receptors (TLRs).

OBJECTIVE

This study investigates the effect of TLR agonists on APCs as well as stimulatory and inhibitory signaling pathways of the T cell-APC interaction.

MATERIALS AND METHODS

Gene expression of interleukin (IL)12 and programmed death ligand 1 (PD-L1) was analyzed by quantitative polymerase chain reaction (qPCR) after 0, 8, 24, and 48 h of CD14⁺ cell stimulation with CpG. Protein expression of inhibitor of nuclear factor kappa B (IκBα) after CpG stimulation was investigated by western blot. CD8⁺ T cells were stimulated for 72 h with or without programmed cell death protein 1 (PD-1) checkpoint blockade and analyzed for expression of PD‑1, Tim‑3, CTLA4, and Lag3 by flow cytometry.

RESULTS

TLR stimulation (by unmethylated CpG DNA) of APCs upregulates immunostimulatory signals such as IL12 expression but also activates immunoinhibitory signaling pathways such as PD-L1 expression. This signaling is NF-κB dependent. After blockade of the PD-1/PD-L1 signaling pathway, overexpression of other immune checkpoint inhibitory receptors was observed-a potential explanation for lacking therapeutic responses after TLR stimulation with PD‑1 checkpoint blockade.

CONCLUSION

TLR stimulation causes APCs in the tumor microenvironment to upregulate PD-L1 in an NF-κB-mediated fashion, thereby contributing to CD8⁺ T cell exhaustion. The effect of PD‑1 blockade after TLR stimulation might be impaired due to upregulation of other checkpoint inhibitors.

Restoration of normal sinus rhythm in atrial fibrillation: impact of reverse remodelling of right chambers on tricuspid regurgitation severity

Background

The severity of tricuspid regurgitation (TR) in patients with restored normal sinus rhythm (SR) after atrial fibrillation (AF) has been poorly assessed.

Purpose

Our study aimed to assess (1) right chamber remodelling and (2) TR severity in patients with AF who have had their rhythms restored to normal sinus.

Methods

We prospectively evaluated 94 consecutive patients hospitalized for AF who received either ablation, direct current cardioversion, or pharmacological therapy. Patients were divided into two groups according to their cardiac rhythm at 6 months follow up (6M): restoration to SR (SR group, n=54), persistence of AF (AF group, n=40). TR vena contracta (VC), TR grade severity was divided into 4 grades using an integrated approach (0: none or trace; 1: mild; 2: moderate; 3: severe TR). Two dimensional (2D) end diastolic (ED) tricuspid annulus (TA) diameter in the apical 4 chambers view, three-dimensional (3D) indexed volumes (3D Vi) of the right atrium (RA) and right ventricle (RV) in end systole (ES) and ED were acquired using transthoracic echocardiography at admission and at 6M.

Results

At 6M, in the SR group a significant improvement in TR VC (Figure A) and TR grade (Figure B) were noted, whereas there was no differences in the AF group (0.41 vs. 0.42cm, p=0.24 for TR VC; 1.70 vs. 1.76, p=0.16 for mean TR grade). In the SR group a significant reduction in 3D ES RV Vi, 2D ED TA diameter, 3D ES and ED Vi of the RA (Table) were observed. Regression of TR VC was correlated with regression of right cavities parameters (ρ=0.47, p&lt;0.001 for 2D ED TA diameter; ρ=0.34, p&lt;0.005 for 3D ES RA Vi; ρ=0.33, p&lt;0.005 for 3D ED RV Vi; ρ=0.29, p&lt;0.005 for 3D ES RV Vi).

Conclusion

Restoration of normal SR in patients with AF results in beneficial remodelling of right cavities at 6M of follow-up which were associated with a significant decrease in TR severity. Strategies for normal SR restoration in patients with AF and TR should be vigorously attempted.

TR Evolution

Funding Acknowledgement

Type of funding source: None

Prognosis of acute kidney injury during acute heart failure: the role of diuretics

Background

Acute kidney injury (AKI) frequently occurs after diuretic treatment initiation during acute heart failure (AHF). Treatment-induced hemoconcentration seems associated with improved prognosis. Transient AKI, with or without hemoconcentration, is of unsettled prognosis.

Purpose

We aimed to determine the independent prognostic values of transient AKI, persistent AKI and hemoconcentration in the context of hospitalized AHF.

Methods

Data were obtained from our institution's Clinical Data Warehouse. Patients that visited our unit at least once were screened. All hospitalizations in our institution were examined (&gt;30 hospitals). Inclusion criteria were: ≥1 hospitalization with ≥1 recorded furosemide administration and ≥1 AHF ICD-10 code. Only the first hospitalization fulfilling these criteria was considered. AKI during 1–13 days following first furosemide administration was defined based on Kidney Disease Improving Global Outcome guidelines. Hemoconcentration was defined as an increase in serum proteins ≥5 g/l during the same period. We performed multivariate logistic regression to determine which characteristics were predictive of AKI. We used Cox regression of 100-days all-cause mortality using several confounders to determine the prognostic values of transient AKI (lasting &lt;14 days), persistent AKI (lasting ≥14 days) and hemoconcentration. To account for immortality bias, AKI and hemoconcentration were treated as time-dependent covariates.

Results

We included 579 patients in the study. Median follow-up was 114 days. AKI following furosemide initiation occurred in 234 patients (40.4%). Patients that experienced AKI more frequently suffered from chronic kidney disease (43.6% vs. 33%, p=0.01) or presented with right ventricular dilatation (12% vs. 6.7%, p=0.04). Independent predictors of AKI were arterial hypertension (adjusted OR: 1.86 [1.08–3.22]), elevated serum creatinine at baseline (adjusted OR: 1.07 [1.01–1.14] per 10 μmol/l increase) and initial intravenous furosemide (adjusted OR: 2.42 [1.39–4.29]). Death during follow-up occurred in 35% of patients in the AKI group compared to 21% in the non-AKI group (p&lt;0.001). In Cox regression, persistent AKI was independently associated with increased mortality in a period of 100 days following furosemide initiation (adjusted HR: 2.31 [1.07–4.99]). Transient AKI was not significantly associated with mortality (adjusted HR: 0.64 [0.34–1.19]). Hemoconcentration was independently associated with decreased mortality (adjusted HR: 0.46 [0.27–0.79]).

Conclusion

In the context of hospitalized AHF, AKI that developed 1–13 days after furosemide initiation and that lasted ≥14 days was independently associated with decreased 100 days survival. Hemoconcentration, using a clinically relevant definition, was independently associated with improved survival. These findings show that serum creatinine and proteins, routinely used and with limited cost, accurately stratify mortality risk during AHF.

Kaplan-Meier curves

Funding Acknowledgement

Type of funding source: None

Cardiac contractility modulation efficacy: is there a difference between ischemic vs. non-ischemic patients?

Background/Introduction

Cardiac contractility modulation (CCM) is an FDA approved device therapy for systolic heart failure patients with narrow QRS complex who are symptomatic despite optimal medical therapy. It is used in patients with a wide range of different cardiomyopathies. However, little is known whether the therapy is comparably effective in different entities.

Purpose

This work investigated the long-term therapeutic effect in patients with ischemic (ICMP) compared to patients with non-ischemic cardiomyopathy (NICMP).

Methods

102 patients of our single center registry with known form of cardiomyopathy were included in this retrospective analysis (from 2011–2019). In 68 patients data of a clinical 3-year follow-up were available. The actual mortality rate within one and three years was compared with the one predicted by the MAGGIC risk score and compared between the two groups. In addition, changes in NYHA class, left ventricular ejection fraction (LVEF), LV end-diastolic diameter (LVEDD) and NT-proBNP values were compared as functional parameters.

Results

Patients with an ICMP (65%) were older (67±1 vs. 57±2 years (SD±SEM); p&lt;0.001) but had a comparable MLHFQ score (42±3 vs. 48±6; p=NS), mean peak VO2 (9.7±1.2 vs. 14.5±2.2 ml/kg/min; p=NS) and QRS width (115±3 vs. 112±4 ms; p=NS). Both groups initially had a comparably advanced limitation during physical activity (median NYHA class III; p=NS); 40% of patients responded with an improvement of at least 1 NYHA class within 3 years (p=NS). The LVEF was 24±1 vs. 22±1% in the beginning and improved to 32±2 vs. 38±2% within 3 years (+33 vs. +73%; p&lt;0.001 in comparison over time; p&lt;0.001 in comparison of the percentage changes ICMP vs. NICMP). While LVEDD was initially significantly wider in NICMP patients (51±2 vs. 67±2 mm; p&lt;0.001), this was offset under therapy, mainly due to a reduction in LVEDD in NICMP patients (+3±2 vs. −7±3 mm; p=0.023). The NT-proBNP values decreased from 4872±776 vs. 5354±1153 to 2051±578 vs. 843±363 ng/l (−58 vs. −84%; p=NS in comparison over time; p=0.093 in comparison of the percentage changes ICMP vs. NICMP). ICMP patients had a higher MAGGIC risk score (27±1 vs. 24±1; p=0.019). Mortality rates at 1 year were 7.4 vs. 17.1% and at 3 years 40.5 vs. 35.5% (each p=NS) compared to mortality rates estimated from the MAGGIC risk score of 21.2 vs. 16.0% (p=0.028) and 44.0 vs. 37.2% (p=0.071), respectively. Chi-square test for comparison of observed and expected frequencies revealed that the number of deaths during 1-year follow-up was significantly lower than predicted only in ICMP patients (p=0.018 compared to the estimated risk).

Conclusions

NICMP patients had a significantly greater increase in LVEF. Moreover, reverse remodeling with reduction of the LVEDD was only observed in NICMP patients. In summary, significant differences in functional therapy response could be identified between ICMP vs. NICMP patients.

Funding Acknowledgement

Type of funding source: None

Impact of rhythm in non-valvular atrial fibrillation on four cardiac chamber deformation imaging

Background

Few studies have assessed the evolution of cardiac chambers deformation imaging in patients with atrial fibrillation (AF) according to cardiac rhythm outcome.

Purpose

To evaluate cardiac chamber deformation imaging in patients admitted for AF and the evolution at 6-month follow-up (M6).

Methods

In forty-one consecutive patients hospitalised for AF two-dimensional transthoracic echocardiography was performed at admission (M0) and after six months (M6) of follow up. In addition to the usual parameters of chamber size and function, chamber deformation imaging was obtained including global left atrium (LA) and right atrium (RA) reservoir strain, global left ventricular (LV) and right ventricular (RV) free wall longitudinal strain. Patients were divided into three groups according to their cardiac rhythm at M0 and M6: AF at M0 and sinus rhythm (SR) at M6 (AF-SR) (n=23), AF at M0 and AF at M6 (AF-AF) (n=11), SR at M0 (spontaneous conversion before the first echocardiography exam) and SR in M6 (SR-SR) (n=7)

Results

In comparison with SR patients (n=7), at M0, AF patients (n=34)) had lower global LA reservoir strain (+5.2 (+0.4 to 12.8) versus +33.2 (+27.0 to +51.5)%; p&lt;0.001), lower global RA reservoir strain (+8.6 (−5.4 to 11.6) versus +24.3 (+12.3 to +44.9)%; p&lt;0.001), lower global LV longitudinal strain (respectively −12.8 (−15.2 to −10.4) versus −19.1 (−21.8 to −18.3)%; p&lt;0.001) and lower global RV longitudinal strain (respectively −14.2 (−17.3 to −10.7) versus −23.8 (−31.1 to −16.2)%; p=0.001). When compared with the AF-SR group at M0 the AF-AF group had no significant differences with regard to global LA and RA reservoir strain, global LV and RV longitudinal strain (Table). Between M0 and M6 there was a significant improvement in global longitudinal strain of the four chambers in the AF-SR group whereas no improvements were noted in the AF-AF and SR-SR group (Figure).

Conclusion

Initial atrial and ventricular deformations were not associated with rhythm outcome at six-month follow up in AF. The improvement in strain in all four chambers strain suggests global reverse remodelling all cardiac cavities with the restoration of sinus rhythm.

Evolution of strain between M0 and M6

Funding Acknowledgement

Type of funding source: None

Psychological interventions for acute psychiatric inpatients with schizophrenia-spectrum disorders: A systematic review and meta-analysis

BACKGROUND

Acute inpatient psychiatric wards are important yet challenging environments in which to implement psychological interventions for people with schizophrenia-spectrum disorders. No meta-analysis to date has evaluated whether psychological interventions are effective in this context.

METHODS

We systematically searched Embase, Medline and PsycInfo databases for randomised controlled trials (RCTs) of psychological interventions implemented in acute inpatient psychiatric settings with individuals with schizophrenia-spectrum disorders. We conducted random effects meta-analyses of between-groups outcomes at post-intervention and relapse/re-hospitalisation rates by follow-up.

RESULTS

Twenty-nine trials were suitable for meta-analysis. Psychological interventions improved post-intervention positive symptoms, social functioning and treatment compliance and reduced the risk of relapse/ re-hospitalisation, relative to control conditions. Analyses of specific intervention effects found positive effects of psychoeducation on several key outcomes (power > 80%) and preliminary evidence for positive effects of acceptance and commitment therapy (ACT), cognitive behaviour therapy (CBT) and metacognitive training (MCT) on some outcomes (power < 80%).

CONCLUSION

Psychological interventions can be helpful for acute inpatients with schizophrenia-spectrum disorders. However, risk of bias was often high or unclear, and some analyses were underpowered. Further research should use more rigorous RCT designs and publish meta-analysable data on positive symptoms, general psychopathology, relapse/ re-hospitalisation, social functioning and treatment compliance.

Dapagliflozin promotes beta cell regeneration by inducing pancreatic endocrine cell phenotype conversion in type 2 diabetic mice

BACKGROUND

Clinical trials and animal studies have shown that sodium-glucose co-transporter type 2 (SGLT2) inhibitors improve pancreatic beta cell function. Our study aimed to investigate the effect of dapagliflozin on islet morphology and cell phenotype, and explore the origin and possible reason of the regenerated beta cells.

METHODS

Two diabetic mouse models, db/db mice and pancreatic alpha cell lineage-tracing (glucagon-β-gal) mice whose diabetes was induced by high fat diet combined with streptozotocin, were used. Mice were treated by daily intragastric administration of dapagliflozin (1 mg/kg) or vehicle for 6 weeks. The plasma insulin, glucagon and glucagon-like peptide-1 (GLP-1) were determined by using ELISA. The evaluation of islet morphology and cell phenotype was performed with immunofluorescence. Primary rodent islets and αTC1.9, a mouse alpha cell line, were incubated with dapagliflozin (0.25-25 μmol/L) or vehicle in the presence or absence of GLP-1 receptor antagonist for 24 h in regular or high glucose medium. The expression of specific markers and hormone levels were determined.

RESULTS

Treatment with dapagliflozin significantly decreased blood glucose in the two diabetic models and upregulated plasma insulin and GLP-1 levels in db/db mice. The dapagliflozin treatment increased islet and beta cell numbers in the two diabetic mice. The beta cell proliferation as indicated by C-peptide and BrdU double-positive cells was boosted by dapagliflozin. The alpha to beta cell conversion, as evaluated by glucagon and insulin double-positive cells and confirmed by using alpha cell lineage-tracing, was facilitated by dapagliflozin. After the dapagliflozin treatment, some insulin-positive cells were located in the duct compartment or even co-localized with duct cell markers, suggestive of duct-derived beta cell neogenesis. In cultured primary rodent islets and αTC1.9 cells, dapagliflozin upregulated the expression of pancreatic endocrine progenitor and beta cell specific markers (including Pdx1) under high glucose condition. Moreover, dapagliflozin upregulated the expression of Pcsk1 (which encodes prohormone convertase 1/3, an important enzyme for processing proglucagon to GLP-1), and increased GLP-1 content and secretion in αTC1.9 cells. Importantly, the dapagliflozin-induced upregulation of Pdx1 expression was attenuated by GLP-1 receptor antagonist.

CONCLUSIONS

Except for glucose-lowering effect, dapagliflozin has extra protective effects on beta cells in type 2 diabetes. Dapagliflozin enhances beta cell self-replication, induces alpha to beta cell conversion, and promotes duct-derived beta cell neogenesis. The promoting effects of dapagliflozin on beta cell regeneration may be partially mediated via GLP-1 secreted from alpha cells.

[The microbiome in head and neck tumors-initial findings and outlook]

Technical progress in molecular biology has allowed for a more detailed analysis of the composition of the human microbiome in recent years. Inter- and intraindividual differences in microbiome composition have been demonstrated, which in part correlate with the occurrence of certain diseases. For some of the so-called oncomicrobes, a direct relationship between their effect on the host organism and carcinogenesis has been demonstrated, predominantly for gastrointestinal cancers. Initial results for head and neck cancer show inter- and intraindividual differences in the local microbiota of the tumor environment, with certain bacterial strains over- or underrepresented. Our results confirm these findings, e.g., by showing a relative abundance of fusobacteria in tumor tissue while streptococci were relatively reduced. Currently available results show a high degree of inter- and intraindividual variation, thus requiring larger patient cohorts for functional analyses.

[Exosomes as immune regulators in head and neck cancer]

Exosomes, virus-sized nanovesicles, are utilized as messenger systems of our body to communicate with other body cells and regulate immune functions. Almost all cells produce exosomes and are able to interact with immune cells in the blood stream and peripheral body areas. Different markers on the surface of exosomes are necessary for immune cell adhesion and interaction. Furthermore, many types of exosome-immune cell interaction, such as surface receptor contact and phagocytosis, are known. As carriers of different cargos, exosomes affect different immune cell types in head and neck cancers: So far, T cells, natural killer cells, macrophages, and dendritic cells have been described in this context. For diagnostic purposes, a combined analysis of different parameters including protein amount, nucleic acid/protein expression, and the immunosuppressive impact of exosomes could empower exosomes as useful tools for evaluation of tumor promotion and progression in the future.

Glucagon receptor antagonism promotes the production of gut proglucagon-derived peptides in diabetic mice

Glucagon is an essential regulator of glucose homeostasis, particularly in type 2 diabetes (T2D). Blocking the glucagon receptor (GCGR) in diabetic animals and humans has been shown to alleviate hyperglycemia and increase circulating glucagon-like peptide-1 (GLP-1) levels. However, the origin of the upregulated GLP-1 remains to be clarified. Here, we administered high-fat diet + streptozotocin-induced T2D mice and diabetic db/db mice with REMD 2.59, a fully competitive antagonistic human GCGR monoclonal antibody (mAb) for 12 weeks. GCGR mAb treatment decreased fasting blood glucose levels and increased plasma GLP-1 levels in the T2D mice. In addition, GCGR mAb upregulated preproglucagon gene expression and the contents of gut proglucagon-derived peptides, particularly GLP-1, in the small intestine and colon. Notably, T2D mice treated with GCGR mAb displayed a higher L-cell density in the small intestine and colon, which was associated with increased numbers of LK-cells coexpressing GLP-1 and glucose-dependent insulinotropic polypeptide and reduced L-cell apoptosis. Furthermore, GCGR mAb treatment upregulated GLP-1 production in the pancreas, which was detected at lower levels than in the intestine. Collectively, these results suggest that GCGR mAb can increase intestinal GLP-1 production and L-cell number by enhancing LK-cell expansion and inhibiting L-cell apoptosis in T2D.

[Effects of the SARS-CoV-2 pandemic on the otorhinolaryngology university hospitals in the field of medical care]

INTRODUCTION

Since December 2019, the SARS-CoV-2 virus has been rapidly spreading worldwide. In Germany, an exponential increase in the number of infections was registered at the beginning of March 2020 and led to a call of the Ministry of Health to create more capacity for intensive medical treatment in hospitals. The aim of the present study was to determine the effects of the SARS-CoV-2 pandemic on Oto-Rhino-Laryngology (ORL) university hospitals regarding patient care.

MATERIALS AND METHODS

An online survey was sent out to all chairmen of the 39 ORL university hospitals in Germany. The answers to the questions referred to the defined period from March 15^th to April 15^th 2020 and were carried out using the online survey tool "SurveyMonkey". 87 questions focused on general information, health care, and structural effects in the respective institution.

RESULTS

All chairmen of the 39 university hospitals in Germany participated in the survey. The collected data prove the considerable impact on organizational, structural and medical aspects of patient care. For example, the surveyed clinics reported a decrease in outpatient cases by 73.8 % to 26.2 ± 14.2 % and in surgical treatments by 65.9 % to 34.1 ± 13.9 %. In contrast, emergency treatment remained unchanged or even increased in 80 % of the facilities and surgical treatment of emergency patients remained unchanged or even increased in more than 90 %. Emergency outpatient and surgical treatment of patients was provided throughout the pandemic in all facilities. In total, about 35 000 outpatients and about 12 000 surgical cases were postponed. As a result of the acute structural changes, the potential danger of falling below current treatment standards was seen in individual areas of patient care.

DISCUSSION

The assessment of the impact of the SARS-CoV-2 pandemic is heterogeneous. The majority of the chairmen are critically aware of the risk of falling below current medical treatment standards or guidelines. In the phase of an exponential increase in the number of infections, significant changes in treatment processes had to be accepted for understandable reasons. However, with the currently significantly reduced number of infections, falling below treatment standards and guidelines should not be allowed to remain constant and tolerated.

SUMMARY

This study shows a differentiated picture with regard to the effects of the SARS-CoV-2 pandemic on outpatient, inpatient and operative patient care at the ORL university hospitals in Germany and illustrates the importance of these institutions for ensuring patient care during this critical phase.

[Primary cutaneous CD4+ small to medium-sized T-cell lymphoma in an adolescent patient]

A rare finding of primary cutaneous CD4+ small to medium-sized T‑cell lymphoma (SMPTCL) in a fifteen-year-old patient is reported. This is a rare tumor entity for which there is currently no standardized treatment recommendation. At the interdisciplinary tumor board, the decision was made to resect the tumor and reconstruct the defect with a nasolabial advancement flap in a two-stage process. Follow-up examinations, currently over 3 years, have shown the patient to be free of recurrences.

[The role of surgery and salvage surgery in the era of HPV-associated oropharyngeal carcinomas]

The incidence of human papillomavirus (HPV)-positive oropharyngeal carcinomas is increasing worldwide. Due to a markedly different response to treatment compared to HPV-negative oropharyngeal carcinomas, determining the ideal therapeutic approach can be challenging. Particularly in never-smokers, HPV-positive oropharyngeal carcinomas respond well to primary radiation therapy; at the same time recent studies indicate comparable survival after primary surgery. For stage I tumors according to TNM‑8, retrospective analyses show very good oncologic outcomes after surgery alone, and no added benefit of adjuvant radio- or chemotherapy. Results of prospective treatment deintensification trials are expected in the coming years. Minimally invasive transoral surgical approaches for selected oropharyngeal cancers can improve preservation of postoperative function and quality of life. For both HPV-positive and HPV-negative oropharyngeal carcinomas, salvage surgery is the treatment of choice for resectable recurrent locoregional disease and resectable distant metastases.

Glucagon receptor antagonist upregulates circulating GLP-1 level by promoting intestinal L-cell proliferation and GLP-1 production in type 2 diabetes

OBJECTIVE

Glucagon receptor (GCGR) blockage improves glycemic control and increases circulating glucagon-like peptide-1 (GLP-1) level in diabetic animals and humans. The elevated GLP-1 has been reported to be involved in the hypoglycemic effect of GCGR blockage. However, the source of this elevation remains to be clarified.

RESEARCH DESIGN AND METHODS

REMD 2.59, a human GCGR monoclonal antibody (mAb), was administrated for 12 weeks in db/db mice and high-fat diet+streptozotocin (HFD/STZ)-induced type 2 diabetic (T2D) mice. Blood glucose, glucose tolerance and plasma GLP-1 were evaluated during the treatment. The gut length, epithelial area, and L-cell number and proliferation were detected after the mice were sacrificed. Cell proliferation and GLP-1 production were measured in mouse L-cell line GLUTag cells, and primary mouse and human enterocytes. Moreover, GLP-1 receptor (GLP-1R) antagonist or protein kinase A (PKA) inhibitor was used in GLUTag cells to determine the involved signaling pathways.

RESULTS

Treatment with the GCGR mAb lowered blood glucose level, improved glucose tolerance and elevated plasma GLP-1 level in both db/db and HFD/STZ-induced T2D mice. Besides, the treatment promoted L-cell proliferation and LK-cell expansion, and increased the gut length, epithelial area and L-cell number in these two T2D mice. Similarly, our in vitro study showed that the GCGR mAb promoted L-cell proliferation and increased GLP-1 production in GLUTag cells, and primary mouse and human enterocytes. Furthermore, either GLP-1R antagonist or PKA inhibitor diminished the effects of GCGR mAb on L-cell proliferation and GLP-1 production.

CONCLUSIONS

The elevated circulating GLP-1 level by GCGR mAb is mainly due to intestinal L-cell proliferation and GLP-1 production, which may be mediated via GLP-1R/PKA signaling pathways. Therefore, GCGR mAb represents a promising strategy to improve glycemic control and restore the impaired GLP-1 production in T2D.

Liraglutide ameliorates palmitate-induced oxidative injury in islet microvascular endothelial cells through GLP-1 receptor/PKA and GTPCH1/eNOS signaling pathways

In type 2 diabetes, lipotoxicity damages islet microvascular endothelial cells (IMECs), leading to pancreatic islet β cell dysfunction directly or indirectly. Glucagon-like peptide-1 (GLP-1) and its analogs have beneficial roles in endothelial cells. However, the protective effects of GLP-1 agents on IMECs and their potential mechanism remained obscure. In this study, exposure of MS-1 (a cell line derived from mouse IMECs) to different concentrations of palmitic acid (PA) was used to establish an injury model. The cells exposed to PA (0.25 mmol/L) were treated with a GLP-1 analog liraglutide (3, 10, 30, and 100 nmol/L). Reactive oxygen species (ROS) generation, apoptosis-related protein level, and endothelin-1 production were detected. The protein levels of signaling molecules were analyzed and specific inhibitors or blockers were used to identify involvement of signaling pathways in the effects of liraglutide. Results showed that PA significantly increased ROS generation and the levels of pro-apoptotic protein Bax, and decreased the levels of anti-apoptotic protein Bcl-2 and the mRNA expression and secretion of endothelin-1. Meanwhile, PA downregulated the protein levels of GLP-1 receptor (GLP-1R), phosphorylated protein kinase A (PKA), guanosine 5'-triphosphate cyclohydrolase 1 (GTPCH1), and endothelial nitric oxide synthase (eNOS). Furthermore, liraglutide ameliorated all these effects of PA in a dose-dependent manner. Importantly, GLP-1R antagonist exendin (9-39), PKA inhibitor H89, GTPCH1 inhibitor 2,4-diamino-6-hydroxypyrimidine, or NOS inhibitor N-nitro-l-arginine-methyl ester abolished the liraglutide-mediated amelioration in PA-impaired MS-1 cells. In conclusion, liraglutide ameliorates the PA-induced oxidative stress, apoptosis, and endothelin-1 secretion dysfunction in mouse IMECs through GLP-1R/PKA and GTPCH1/eNOS signaling pathways.

P350 Right atrial remodelling in atrial fibrillation using three dimensional transthoracic echocardiography and strain imaging

Background

Evaluation of right atrial cavities and right atrial (RA) remodelling in atrial fibrillation (AF) has been poorly studied.

Purpose

The aim of this study was to evaluate in AF, the role of three-dimensional (3D) transthoracic echocardiography (TTE) and strain to refine the evaluation of the RA according to evolution of cardiac rhythm ad mid-term follow-up.

Methods

A complete 2D and 3D TTE was performed in patient hospitalized for AF. In addition to the usual parameters, RA parameters were specifically assessed: 3D RA end-systolic (ES) and end-diastolic (ED) volume, RA ejection fraction (EF) and the global longitudinal strain (GLS) of the RA. A complete clinical evaluation and electrocardiogram were performed at admission (M0) and 6 months after inclusion (M6) to determine the cardiac rhythm at follow-up.

Results

34 consecutive patients hospitalized for AF were analysed. At M0, there was no significant difference between 2D RA ES volume and the 3D RA ES volume. Three groups of patients were individualized according to cardiac rhythm at M0 and M6: AF at M0 and AF at M6 (AF-AF), AF at M0 and sinus rhythm (SR) at M6 (AF-SR), SR at M0 (spontaneous reduction before the admission ECG) and SR at M6 (SR-SR). At M0 echocardiography, in the AF-AF group and AF-SR in comparison with SR-SR group were as follow: the 3D RA ED volume was significantly higher (respectively 21.6 (18.2-26.6) and 26.9 (19.4-36.8) versus 11.3 (6.9-16.6) mL/m2 ; p = 0.0025), the 3D RAEF was significantly lower (42.2 (35.1-44.7) and 34.5 (24.1-38.6) versus 57.6 (53.4-62.2)%; p = 0.0105) and the RA GLS was also significantly lower (7.6 (6.5-10.5) and 9.1 (5.8-11.2) versus 26.6 (22.0-35.0)%; p = 0.0001) (Figure 1).

Conclusion

3D ultrasound and strain could be useful tools for evaluating the anatomical and functional RA remodelling in AF, to be further validated in a larger ongoing study.

Abstract P350 Figure 1

Assessing the validity of EQ-5D-5L in people with head & neck cancer: Does a generic quality of life measure perform as well as a disease-specific measure in a patient population?

BACKGROUND

Head and neck cancer (HNC) is an important cause of morbidity and mortality globally. Radical treatment methods may result in facial disfigurement and/or functional difficulties with subsequent adverse impacts on health-related quality of life (HRQoL). Guidelines suggest that HRQoL should be measured repeatedly throughout treatment to enable refined treatment protocols and tailored follow-up support but questionnaires are often long and burdensome. We compared condition-specific and generic metrics to assess HRQoL for people with this condition.

METHODS

We used data from the prospective Head and Neck 5000 clinical cohort study - 5511 participants with a new diagnosis of HNC between 2011 and 2014. HRQoL data were collected at baseline from 2065 people who completed both the condition-specific EORTC-QLQ-C30 and the shorter, generic EQ-5D-5L questionnaires.

RESULTS

There was strong evidence of association between comparable scales on each questionnaire at baseline: higher levels of functioning and lower levels of reported symptoms assessed with EQ-5D-5L were associated with lower EORTC-QLQ-C30 symptom scores. A moderate relationship (0.61) was found between overall QoL in the EQ-5D-5L index and self-perceived health (EQ VAS).

CONCLUSIONS

HRQoL data collected from the generic EQ-5D-5L and cancer-specific EORTC-QLQ-C30 questionnaires are comparable at baseline for people diagnosed with HNC. This would allow a reduced burden of data collection but the EQ-5D-5L may not be sensitive to some condition-specific symptoms. Clinicians and researchers must clarify their aims and outcomes of interest before choosing their HRQoL measures. Further work is required to examine the ability to detect change in these measures over time.

[Surgical management of firework-induced eyelid injuries]

Fireworks injuries are frequently caused by malfunction or incorrect operation of fireworks. Injuries often affect the eyeball and the periorbit. After treatment of life-threatening bleeding, injuries of the eyeball have priority over the treatment of periorbital lacerations and burns. The aim of eyelid surgery in firework-related injuries is to prevent delayed damage, such as lagophthalmos, symblepharon, entropion with trichiasis, and keratinization of the conjunctiva of the eyelid and eyelid margin. The treatment requires a considerable amount of time and patience both for the elaborate surgical procedures as well as for the necessary healing and rest phases. Many patients, however, are left with serious visual impairments and stressful esthetic deformities, which result in considerable occupational and social impairments.

P5338Atherosclerotic cardiovascular events in people living with Human Immunodeficiency Virus

Background

People living with Human Immunodeficiency Virus (PLWHIV) under antiretrovirals have an increased risk of atherosclerotic cardiovascular disease (ASCVD) events. The risk factors associated with ASCVD events in this high risk population are various including traditional vascular risk factors and specific HIV-related factors. However their respective influence is questionable.

Purpose

Our aim was to determine the incidence of ASCVD events in a large cohort of PLWHIV and to identify the risk factors associated.

Methods

We conducted a longitudinal observational cohort study of asymptomatic PLWHIV at high risk of ASCVD addressed to our preventive cardiovascular unit for non-invasive cardiovascular evaluation. The first ASCVD event was censored and included CV death, acute coronary syndromes, coronary and peripheral revascularizations (PCI or CABG or endarterectomy or limb procedures) and ischemic strokes.

Results

From January 2003 to December 2014, 763 consecutive asymptomatic PLWHIV were enrolled (mean age of 51.3±8.3 years, 87% men, 90% were free of known coronary artery disease, mean Left ventricular ejection fraction 60%). At baseline, traditional CV risk factors were as follow: 54% had dyslipidemia, 43% hypertension, 35% were active smokers, 22% had family history of CAD and 11% were diabetics. Statins were prescribed in 38% of the cohort, aspirin in 14%, clopidogrel in 14% betablockers in 14%, RAS blockers in 32%, Calcium channel blockers in 8%. At baseline, median duration of HIV seropositivity was 19.8 years (14.0–23.6), 94% were under ARV predominantly protease inhibitors (68%). Median CD4 cell count was 545/mm3 (404–745) and 92% had undetectable HIV viral load. During a median follow up of 5.8 years (3.7–8.7), 58 (7.3%) subjects had a first ASCVD event (incidence of 12.70 [9.78–16.51] per 1000 persons-years) including 5 cardiovascular deaths, 14 ACS, 20 coronary revascularizations, 13 peripheral vascular procedures and 6 strokes) with a median time of occurrence of 3.1 years (1.5–5.1). CV death (first and second ASCVD events) occurred in 8 patients (22%) after CV death related to malignancies (33%) but before deaths related to unexplained causes (21%), infectious disease (13%), liver disease (8%) and suicides (3%). Coronary events including coronary death, MI, and coronary revascularization occurred in 39 patients (5.2%); Incidence of 8.28 [6.00–11.43] per 1000 persons-years. Conventional multivariate Cox model shows that age and tobacco were the independent risk factors associated with ACSVD events [Hazard ratio (HR) 1.04, 95% CI 0.99–1.09, p=0.05 and HR 2.17, 95% CI 1.07–4.38, p=0.03].

Conclusion

Traditional vascular risk factors (age and active smoking) are associated with the occurrence of ASCVD events predominantly coronary artery disease in our observational cohort of asymptomatic PLWIHV at high risk for ASCVD. Cardiovascular prevention including tobacco cease action is mandatory in the aging HIV population.

1206Doxapram is a promising new antiarrhythmic drug for an atrial-specific therapy of atrial fibrillation

Background

TASK-1 (K2P3.1) is an atrial-specific two-pore domain potassium channel that is significantly upregulated in atrial fibrillation (AF) patients resulting in shortened atrial action potential duration (APD). Inhibition of TASK-1 in human atrial cardiomyocytes reverses AF-related APD shortening to values observed in patients with sinus rhythm (SR). By in silico-modelling and experimental characterization of drug binding sites, doxapram was identified as specific inhibitor of TASK-1.

Purpose

In this study, we investigated the antiarrhythmic efficacy of doxapram in a porcine model of AF to convert and suppress AF.

Methods

We established a new porcine model of persistent AF without induced tachymyopathy. AF was induced in domestic pigs by intermittent atrial burst stimulation using implanted pacemakers. During AF episodes, burst stimulation was inhibited by an integrated pacemaker biofeedback algorithm. AV-node ablation was performed to prevent AF-associated heart failure. All pigs underwent catheter-based electrophysiological investigations prior to and after 14 days doxapram treatment. Pigs in the treatment group received intravenous applications of doxapram twice per day. Rhythm status was continuously recorded by intracardiac long-term ECG monitors. The application of doxapram for cardioversion and long term suppression of AF in pigs with persistent AF was evaluated. Subsequent to the doxapram treatment, porcine cardiomyocytes were isolated from right and left atria and electrophysiologically investigated by patch-clamp and multi-electrode experiments. Atrial electrical remodeling was characterized by analyses of ion channel expression at mRNA and protein levels.

Results

TASK-1 mRNA, protein and transmembrane current were significantly increased in AF pigs compared to SR controls, resulting in shortened atrial APDs. In doxapram-treated AF pigs the AF burden was significantly reduced. After 14 days treatment with doxapram, TASK-1 currents and atrial APDs recorded in porcine cardiomyocytes were reduced and similar to values of SR animals. Doxapram could be successfully applied for cardioversion in pigs with persistent AF. On average, cardioversion was observed 3 minutes after doxapram application.

Conclusion

Doxapram significantly suppressed AF episodes and normalized cellular electrophysiological characteristics in a porcine model of AF through inhibition of the TASK-1 ion channel. Furthermore, doxapram rapidly converted AF into SR in pigs. Therefore, doxapram might serve as a new antiarrhythmic drug to treat AF in patients.

Quantitative and Qualitative Comparison of 4D-DSA with 3D-DSA Using Computational Fluid Dynamics Simulations in Cerebral Aneurysms

BACKGROUND AND PURPOSE

4D-DSA allows time-resolved 3D imaging of the cerebral vasculature. The aim of our study was to evaluate this method in comparison with the current criterion standard 3D-DSA by qualitative and quantitative means using computational fluid dynamics.

MATERIALS AND METHODS

3D- and 4D-DSA datasets were acquired in patients with cerebral aneurysms. Computational fluid dynamics analysis was performed for all datasets. Using computational fluid dynamics, we compared 4D-DSA with 3D-DSA in terms of both aneurysmal geometry (quantitative: maximum diameter, ostium size [OZ1/2], volume) and hemodynamic parameters (qualitative: flow stability, flow complexity, inflow concentration; quantitative: average/maximum wall shear stress, impingement zone, low-stress zone, intra-aneurysmal pressure, and flow velocity). Qualitative parameters were descriptively analyzed. Correlation coefficients (r, P value) were calculated for quantitative parameters.

RESULTS

3D- and 4D-DSA datasets of 10 cerebral aneurysms in 10 patients were postprocessed. Evaluation of aneurysmal geometry with 4D-DSA (r _{maximum diameter} = 0.98, P _{maximum diameter} <.001; r _OZ1/OZ2 = 0.98/0.86, P _OZ1/OZ2 < .001/.002; r _volume = 0.98, P _volume <.001) correlated highly with 3D-DSA. Evaluation of qualitative hemodynamic parameters (flow stability, flow complexity, inflow concentration) did show complete accordance, and evaluation of quantitative hemodynamic parameters (r _{average/maximum wall shear stress diastole} = 0.92/0.88, P _{average/maximum wall shear stress diastole} < .001/.001; r _{average/maximum wall shear stress systole} = 0.94/0.93, P _{average/maximum wall shear stress systole} < .001/.001; r _{impingement zone} = 0.96, P _{impingement zone} < .001; r _{low-stress zone} = 1.00, P _{low-stress zone} = .01; r _{pressure diastole} = 0.84, P _{pressure diastole} = .002; r _{pressure systole} = 0.9, P _{pressure systole} < .001; r _{flow velocity diastole} = 0.95, P _{flow velocity diastole} < .001; r _{flow velocity systole} = 0.93, P _{flow velocity systole} < .001) did show nearly complete accordance between 4D- and 3D-DSA.

CONCLUSIONS

Despite a different injection protocol, 4D-DSA is a reliable basis for computational fluid dynamics analysis of the intracranial vasculature and provides equivalent visualization of aneurysm geometry compared with 3D-DSA.

Nasal self-packing for epistaxis in Hereditary Hemorrhagic Telangiectasia increases quality of life

STATEMENT OF PROBLEM

Hereditary hemorrhagic telangiectasia (HHT) is characterized by recurrent epistaxis that can lead to a feeling of losing control. We assessed potential benefits and side effects of different nasal packings used by patients themselves.

METHOD OF STUDY

An online-questionnaire in English and German was used to analyze nasal self-packings.

RESULTS

588 of the 915 respondents suffered from HHT with most of them having moderate or severe epistaxis. Almost two thirds of the patients had already treated themselves with nasal packings. While one quarter used non-pneumatic nasal packings (NPNP) or pneumatic nasal packings (PNP), nearly half of the patients took only tissues to stop the bleeding. Patients with severe epistaxis used PNP more often than NPNP. Using nasal packings, most patients could stop their nosebleeds after a while. Patients using PNP reported the feeling of losing control less often and significant improvements in quality of life with a positive GBI.

CONCLUSIONS

Our study showed that most patients with HHT using nasal self-packings could stop the bleeding after a while. Nasal self-packing is a user-friendly and secure method leaving patients more self-confident and independent.