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Background: Computerized virtual patients (VP) have spread into many areas of healthcare delivery and medical education. They provide various advantages like flexibility in pace and space of learning, a high degree of teaching reproducibility and a cost effectiveness. However, the educational benefit of VP as an additive or also as an alternative to traditional teaching formats remains unclear. Moreover, there are no randomized-controlled studies that investigated the use of VP in a dental curriculum. Therefore, this study investigates VP as an alternative to lecturer-led small-group teaching in a curricular, randomized and controlled setting.
Methods: Randomized and controlled cohort study. Four VP cases were created according to previously published design principles and compared with lecturer-led small group teaching (SGT) within the Oral and Maxillofacial Surgery clerkship for dental students at the Department for Cranio-, Oral and Maxillofacial Plastic Surgery, Goethe University, Frankfurt, Germany. Clinical competence was measured prior (T0), directly (T1) and 6 weeks (T2) after the intervention using theoretical tests and a self-assessment questionnaire. Furthermore, VP design was evaluated using a validated toolkit.
Results: Fifty-seven students (VP = 32; SGT = 25) agreed to participate in the study. No competence differences were found at T0 (p = 0.56). The VP group outperformed (p < .0001) the SGT group at T1. At T2 there was no difference between both groups (p = 0.55). Both interventions led to a significant growth in self-assessed competence. The VP group felt better prepared to diagnose and treat real patients and regarded VP cases as a rewarding learning experience.
Conclusions: VP cases are an effective alternative to lecture-led SGT in terms of learning efficacy in the short and long-term as well as self-assessed competence growth and student satisfaction. Furthermore, integrating VP cases within a curricular Oral and Maxillofacial Surgery Clerkship is feasible and leads to substantial growth of clinical competence in undergraduate dental students.
Advances in flow cytometry enable the acquisition of large and high-dimensional data sets per patient. Novel computational techniques allow the visualization of structures in these data and, finally, the identification of relevant subgroups. Correct data visualizations and projections from the high-dimensional space to the visualization plane require the correct representation of the structures in the data. This work shows that frequently used techniques are unreliable in this respect. One of the most important methods for data projection in this area is the t-distributed stochastic neighbor embedding (t-SNE). We analyzed its performance on artificial and real biomedical data sets. t-SNE introduced a cluster structure for homogeneously distributed data that did not contain any subgroupstructure. Inotherdatasets,t-SNEoccasionallysuggestedthewrongnumberofsubgroups or projected data points belonging to different subgroups, as if belonging to the same subgroup. As an alternative approach, emergent self-organizing maps (ESOM) were used in combination with U-matrix methods. This approach allowed the correct identification of homogeneous data while in sets containing distance or density-based subgroups structures; the number of subgroups and data point assignments were correctly displayed. The results highlight possible pitfalls in the use of a currently widely applied algorithmic technique for the detection of subgroups in high dimensional cytometric data and suggest a robust alternative.
Background: Glial cells in the central nervous system play a key role in neuroinflammation and subsequent central sensitization to pain. They are therefore involved in the development of persistent pain. One of the main sites of interaction of the immune system with persistent pain has been identified as neuro-immune crosstalk at the glialopioid interface. The present study examined a potential association between the DNA methylation of two key players of glial/opioid intersection and persistent postoperative pain. Methods: In a cohort of 140 women who had undergone breast cancer surgery, and were assigned based on a 3year follow-up to either a persistent or non-persistent pain phenotype, the role of epigenetic regulation of key players in the glial-opioid interface was assessed. The methylation of genes coding for the Toll-like receptor 4 (TLR4) as a major mediator of glial contributions to persistent pain or for the μ-opioid receptor (OPRM1) was analyzed and its association with the pain phenotype was compared with that conferred by global genome-wide DNA methylation assessed via quantification of the methylation in the retrotransposon LINE1. Results: Training of machine learning algorithms indicated that the global DNA methylation provided a similar diagnostic accuracy for persistent pain as previously established non-genetic predictors. However, the diagnosis can be based on a single DNA based marker. By contrast, the methylation of TLR4 or OPRM1 genes could not contribute further to the allocation of the patients to the pain-related phenotype groups. Conclusions: While clearly supporting a predictive utility of epigenetic testing, the present analysis cannot provide support for specific epigenetic modulation of persistent postoperative pain via methylation of two key genes of the glial-opioid interface.
The aim of this study was to determine association between constitutional, medical history and axiographic parameters with postural control parameters. Overall, 106 healthy female subjects aged between 21 and 30 years were measured. Data collection was carried out by completing a questionnaire on constitutional parameters, illnesses, accidents and medical/orthodontic therapies, as well as by axio- and posturographic measurements. Data were analyzed using correlations, pair comparisons and group comparisons. The significance level was set at p ≤ 0.05. The statistical evaluation showed significant correlations between sporting exercise and body sway in the sagittal direction (p ≤ 0.03), the BMI and the load on the forefoot/rear foot (p ≤ 0.01), the mouth opening and the load on the forefoot/rearfoot (p ≤ 0.01) and the presence of a deviation with the load on the left/right foot (p ≤ 0.01). The physical condition as well as the temporo-mandibular system are associated with the postural control in young women. Therefore, a holistic diagnosis and therapy will be supported by the present outcomes.
Omeprazole was shown to improve the anti-cancer effects of the nucleoside analogue 5-fluorouracil. Here, we combined omeprazole with the antiviral nucleoside analogues ribavirin and acyclovir. Omeprazole did not affect the antiviral effects of ribavirin in non-toxic concentrations up to 80 μg/mL but increased the acyclovir-mediated effects on herpes simplex virus 1 and 2 (HSV-1 and -2) replication in a dose-dependent manner. Omeprazole alone reduced HSV-1 and -2 titers [but not HSV-induced formation of cytopathogenic effects (CPE)] at concentrations ≥40 μg/mL. However, it exerted substantially stronger effects on acyclovir activity and also increased acyclovir activity at lower concentrations that did not directly interfere with HSV replication. Omeprazole 80 μg/mL caused a 10.8-fold (Vero cells) and 47.7-fold (HaCaT cells) decrease of the acyclovir concentrations that reduced HSV-1-induced CPE formation by 50% (IC50). In HSV-2-infected cells, omeprazole 80 μg/mL reduced the acyclovir IC50 by 7.3- (Vero cells) and 12.9-fold (HaCaT cells). In HaCaT cells, omeprazole 80 μg/mL reduced the HSV-1 titer in the presence of acyclovir 1 μg/mL by 1.6 × 105-fold and the HSV-2 titer in the presence of acyclovir 2 μg/mL by 9.2 × 103-fold. The proton pump inhibitors pantoprazole, rabeprazole, lansoprazole, and dexlansoprazole increased the antiviral effects of acyclovir in a similar fashion as omeprazole, indicating this to be a drug class effect. In conclusion, proton pump inhibitors increase the anti-HSV activity of acyclovir and are candidates for antiviral therapies in combination with acyclovir, in particular for topical preparations for the treatment of immunocompromised individuals who are more likely to suffer from severe complications.
Platelet-rich fibrin (PRF) is a blood concentrate derived from venous blood that is processed without anticoagulants by a one-step centrifugation process. This three-dimensional scaffold contains inflammatory cells and plasma proteins entrapped in a fibrin matrix. Liquid-PRF was developed based on the previously described low-speed centrifuge concept (LSCC), which allowed the introduction of a liquid-PRF formulation of fibrinogen and thrombin prior to its conversion to fibrin. Liquid-PRF was introduced to meet the clinical demand for combination with biomaterials in a clinically applicable and easy-to-use way. The aim of the present study was to evaluate, ex vivo, the interaction of the liquid-PRF constituents with five different collagen biomaterials by histological analyses. The results first demonstrated that large variability existed between the biomaterials investigated. Liquid-PRF was able to completely invade Mucograft® (MG; Geistlich Biomaterials, Wolhusen, Switzerland) and to partly invade Bio-Gide® (BG; Geistlich Biomaterials, Wolhusen, Switzerland) and Mucoderm® (MD; Botiss Biomaterials, Berlin, Germany), and Collprotect® (CP; Botiss Biomaterials, Berlin, Germany) showed only a superficial interaction. The BEGO® collagen membrane (BCM; BEGO Implant Systems) appeared to be completely free of liquid-PRF. These results were confirmed by the different cellular penetration and liquid-PRF absorption coefficient (PAC) values of the evaluated membranes. The present study demonstrates a system for loading biomaterials with a complex autologous cell system (liquid-PRF) in a relatively short period of time and in a clinically relevant manner. The combination of biomaterials with liquid-PRF may be clinically utilized to enhance the bioactivity of collagen-based biomaterials and may act as a biomaterial-based growth factor delivery system.
Background: Accurate assessment of hepatic fibrosis in patients with chronic HBeAg-negative Hepatitis B is of crucial importance not only to predict the long-term clinical course, but also to evaluate antiviral therapy indication. The aim of this study was to prospectively assess the utility of point shear wave elastography (pSWE) for longitudinal non-invasive fibrosis assessment in a large cohort of untreated patients with chronic HBeAg-negative hepatitis B virus (HBV) infection.
Methods: 407 consecutive patients with HBeAg-negative HBV infection who underwent pSWE, transient elastography (TE) as well as laboratory fibrosis markers, including fibrosis index based on four factors (FIB-4), aspartate to platelet ratio index (APRI) and FibroTest, on the same day were prospectively followed up for six years. Patients were classified into one of the three groups: inactive carriers (IC; HBV-DNA <2000 IU/mL and ALT <40 U/L); grey zone group 1 (GZ-1; HBV DNA <2000 IU/mL and ALT >40 U/L); grey zone group 2 (GZ-2; HBV-DNA >2000 IU/mL and ALT <40 U/L).
Results: pSWE results were significantly correlated with TE (r = 0.29, p < 0.001) and APRI (r = 0.17; p = 0.005). Median pSWE values did not differ between IC, GZ-1 and GZ-2 patients (p = 0.82, p = 0.17, p = 0.34). During six years of follow-up, median pSWE and TE values did not differ significantly over time (TE: p = 0.27; pSWE: p = 0.05).
Conclusion: Our data indicate that pSWE could be useful for non-invasive fibrosis assessment and follow-up in patients with HBeAg-negative chronic HBV infection.
Background and Aims: The IL-12/23 inhibitor ustekinumab (UST) opened up new treatment options for patients with Crohn’s disease (CD). Due to the recent approval, real-world German data on long-term efficacy and safety are lacking. This study aimed to assess the clinical course of CD patients under UST therapy and to identify potential predictive markers.
Methods: Patients with CD receiving UST treatment in three hospitals and two outpatient centers were included and retrospectively analyzed. Rates for short- and long-term remission and response were analyzed with the help of clinical (Harvey–Bradshaw Index (HBI)) and biochemical (C-reactive protein (CRP), Fecal calprotectin (fCal)) parameters for disease activity.
Results: Data from 180 patients were evaluated. One-hundred-and-six patients had a follow-up of at least eight weeks and were included. 96.2% of the patients were pre-exposed to anti- TNFα agents and 34.4% to both anti-TNFα and anti-integrin antibodies. The median follow-up was 49.1 weeks (95% CI 42.03-56.25). At week 8, 51 patients (54.8%) showed response to UST, and 24 (24.7%) were in remission. At week 48, 48 (51.6%) responded to UST, and 25 patients (26.9%) were in remission. Steroid-free response and remission at week eight was achieved by 30.1% and 19.3% of patients, respectively. At week 48, 37.6% showed steroid-free response to UST, and 20.4% of the initial patient population was in steroid-free remission.
Conclusion: Our study confirms short- and long-term UST effectiveness and tolerability in a cohort of multi-treatment-exposed patients.
(1) Background: A lesion within the dentato-rubro-olivary pathway (DROP) in the posterior fossa can cause secondary neurodegeneration of the inferior olivary nucleus: so-called hypertrophic olivary degeneration (HOD). The clinical syndrome of HOD occurs slowly over months and may be overlooked in progressive neuro-oncological diseases. Posterior fossa tumors are often located near these strategic structures. The goal of this study was to analyze the systematics of HOD occurrence in neuro-oncological patients.
(2) Methods: The neuroradiological database of the university healthcare center was scanned for HOD-related terms from 2010 to 2019. After excluding patients with other causes of HOD, 12 datasets from neuro-oncological patients were analyzed under predetermined criteria.
(3) Results: Patients received multimodal tumor treatments including neurosurgery, radiotherapy, and chemotherapy. HOD occurred both unilaterally (left n = 4; right n = 5) and bilaterally (n = 3). Though the mass effect of posterior fossa tumors had already affected strategic structures of the DROP, none of the patients showed signs of HOD on MRI until therapeutic measures including neurosurgery affecting the DROP were applied. HOD was visible on MRI within a median of 6 months after the neurosurgical intervention. In 67%, the presumed underlying surgical lesion in the DROP lay in the contralateral dentate nucleus.
(4) Conclusion: In a selected cohort of neuro-oncological patients, therapeutic lesions within the DROP were associated with HOD occurrence.
Immunosuppressive compounds affect the fungal growth and viability of defined aspergillus species
(2019)
Immunosuppressive drugs are administered to a number of patients; e.g., to allogeneic hematopoietic stem cell transplant recipients. Immunosuppressive drugs impair the immune system and thus increase the risk of invasive fungal disease, but may exhibit antifungal activity at the same time. We investigated the impact of various concentrations of three commonly used immunosuppressive compounds—cyclosporin A (CsA), methylprednisolone (mPRED), and mycophenolic acid (MPA)—on the growth and viability of five clinically important Aspergillus species. Methods included disc diffusion, optical density of mycelium, and viability assays such as XTT. MPA and CsA had a species-specific and dose-dependent inhibitory effect on the growth of all Aspergillus spp. tested, although growth inhibition by MPA was highest in A. niger, A. flavus and A. brasiliensis. Both agents exhibited species-specific hyphal damage, which was higher when the immunosuppressants were added to growing conidia than to mycelium. In contrast, mPRED increased the growth of A. niger, but had no major impact on the growth and viability of any of the other Aspergillus species tested. Our findings may help to better understand the interaction of drugs with Aspergillus species and ultimately may have an impact on individualizing immunosuppressive therapy.