Virtual reality simulation to enhance advanced trauma life support trainings - a randomized controlled trial.

BACKGROUND: Advanced Trauma Life Support (ATLS) is the gold standard of initial assessment of trauma patients and therefore a widely used training program for medical professionals. Practical application of the knowledge taught can be challenging for medical students and inexperienced clinicians. Simulation-based training, including virtual reality (VR), has proven to be a valuable adjunct to real-world experiences in trauma education. Previous studies have demonstrated the effectiveness of VR simulations for surgical and technical skills training. However, there is limited evidence on VR simulation training specifically for trauma education, particularly within the ATLS curriculum. The purpose of this pilot study is to evaluate the feasibility, effectiveness, and acceptance of using a fully immersive VR trauma simulation to prepare medical students for the ATLS course. METHODS: This was a prospective randomised controlled pilot study on a convenience sample of advanced medical students (n = 56; intervention group with adjunct training using a commercially available semi-automated trauma VR simulation, n = 28, vs control group, n = 28) taking part in the ATLS course of the Military Physician Officer School. Feasibility was assessed by evaluating factors related to technical factors of the VR training (e.g. rate of interruptions and premature termination). Objective and subjective effectiveness was assessed using confidence ratings at four pre-specified points in the curriculum, validated surveys, clinical scenario scores, multiple choice knowledge tests, and ATLS final clinical scenario and course pass rates. Acceptance was measured using validated instruments to assess variables of media use (Technology acceptance, usability, presence and immersion, workload, and user satisfaction). RESULTS: The feasibility assessment demonstrated that only one premature termination occurred and that all remaining participants in the intervention group correctly stabilised the patient. No significant differences between the two groups in terms of objective effectiveness were observed (p = 0.832 and p = 0.237 for the pretest and final knowledge test, respectively; p = 0.485 for the pass rates for the final clinical scenario on the first attempt; all participants passed the ATLS course). In terms of subjective effectiveness, the authors found significantly improved confidence post-VR intervention (p < .001) in providing emergency care using the ATLS principles. Perceived usefulness in the TEI was stated with a mean of 4 (SD 0.8; range 0-5). Overall acceptance and usability of the VR simulation was rated as positive (System Usability Scale total score mean 79.4 (SD 11.3, range 0-100). CONCLUSIONS: The findings of this prospective pilot study indicate the potential of using VR trauma simulations as a feasible and acceptable supplementary tool for the ATLS training course. Where objective effectiveness regarding test and scenario scores remained unchanged, subjective effectiveness demonstrated improvement. Future research should focus on identifying specific scenarios and domains where VR can outperform or enhance traditional learning methods in trauma simulation.

Self-Assembly of Rhamnolipid Bioamphiphiles: Understanding the Structure-Property Relationship Using Small-Angle X-ray Scattering.

The structure-property relationship of rhamnolipids, RLs, well-known microbial bioamphiphiles (biosurfactants), is explored in detail by coupling cryogenic transmission electron microscopy (cryo-TEM) and both ex situ and in situ small-angle X-ray scattering (SAXS). The self-assembly of three RLs with reasoned variation of their molecular structure (RhaC10, RhaC10C10, and RhaRhaC10C10) and a rhamnose-free C10C10 fatty acid is studied in water as a function of pH. It is found that RhaC10 and RhaRhaC10C10 form micelles in a broad pH range and RhaC10C10 undergoes a micelle-to-vesicle transition from basic to acid pH occurring at pH 6.5. Modeling coupled to fitting SAXS data allows a good estimation of the hydrophobic core radius (or length), the hydrophilic shell thickness, the aggregation number, and the surface area per RL. The essentially micellar morphology found for RhaC10 and RhaRhaC10C10 and the micelle-to-vesicle transition found for RhaC10C10 are reasonably well explained by employing the packing parameter (PP) model, provided a good estimation of the surface area per RL. On the contrary, the PP model fails to explain the lamellar phase found for the protonated RhaRhaC10C10 at acidic pH. The lamellar phase can only be explained by values of the surface area per RL being counterintuitively small for a di-rhamnose group and folding of the C10C10 chain. These structural features are only possible for a change in the conformation of the di-rhamnose group between the alkaline and acidic pH.

Exploiting the Natural Diversity of RhlA Acyltransferases for the Synthesis of the Rhamnolipid Precursor 3-(3-Hydroxyalkanoyloxy)Alkanoic Acid.

While rhamnolipids of the Pseudomonas aeruginosa type are commercially available, the natural diversity of rhamnolipids and their origin have barely been investigated. Here, we collected known and identified new rhlA genes encoding the acyltransferase responsible for the synthesis of the lipophilic rhamnolipid precursor 3-(3-hydroxyalkanoyloxy)alkanoic acid (HAA). Generally, all homologs were found in Betaproteobacteria and Gammaproteobacteria A likely horizontal gene transfer event into Actinobacteria is the only identified exception. The phylogeny of the RhlA homologs from Pseudomonas and Burkholderia species is consistent with the organism phylogeny, and genes involved in rhamnolipid synthesis are located in operons. In contrast, RhlA homologs from the Enterobacterales do not follow the organisms' phylogeny but form their own branch. Furthermore, in many Enterobacterales and Halomonas from the Oceanospirillales, an isolated rhlA homolog can be found in the genome. The RhlAs from Pseudomonas aeruginosa PA01, Pseudomonas fluorescens LMG 05825, Pantoea ananatis LMG 20103, Burkholderia plantarii PG1, Burkholderia ambifaria LMG 19182, Halomonas sp. strain R57-5, Dickeya dadantii Ech586, and Serratia plymuthica PRI-2C were expressed in Escherichia coli and tested for HAA production. Indeed, except for the Serratia RhlA, HAAs were produced with the engineered strains. A detailed analysis of the produced HAA congeners by high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) highlights the congener specificity of the RhlA proteins. The congener length varies from 4 to 18 carbon atoms, with the main congeners consisting of different combinations of saturated or monounsaturated C10, C12, and C14 fatty acids. The results are discussed in the context of the phylogeny of this unusual enzymatic activity.IMPORTANCE The RhlA specificity explains the observed differences in 3-(3-hydroxyalkanoyloxy)alkanoic acid (HAA) congeners. Whole-cell catalysts can now be designed for the synthesis of different congener mixtures of HAAs and rhamnolipids, thereby contributing to the envisaged synthesis of designer HAAs.

Depression, anxiety disorders, and metabolic syndrome in a population at risk for type 2 diabetes mellitus.

BACKGROUND: Depressive symptoms have been associated with type 2 diabetes mellitus (T2DM), but less is known about anxiety disorders that can be comorbid or exist without depression. METHODS: We evaluated the prevalence of psychiatric disorders in subjects consecutively examined at an outpatient clinic for diabetes prevention who were at-risk for T2DM, defined by FINDRISK scores, and compared metabolic syndrome (MetS) frequencies between subjects with and without psychiatric morbidity, entering also relevant variables for MetS into multivariate analyses. All subjects underwent an oral glucose tolerance test (OGTT). Psychiatric diagnosis was confirmed using a Structured Clinical Interview for DSM-IV. RESULTS: Of 260 consecutively screened subjects, 150 (56.9±8.1 years old, males=56.7%, BMI=27.2±4.1 kg/m2) were at-risk for T2DM and were included. MetS, present in 27% of males and 25% of females, was significantly associated with having a current anxiety disorder (P<0.001) and lifetime major depression (P<0.001). In logistic regression analysis, MetS was significantly associated with lifetime major depression, presence of any anxiety disorder, body weight, and physical activity. CONCLUSIONS: Our data in a high-risk group for T2DM support the association between depressive disorders and MetS, pointing to a similar role of anxiety disorders. Screening for anxiety and depression is recommended in this group at risk for T2DM.

Diagnostic value of nucleolar organizer regions (AgNORs) in brush biopsies of suspicious lesions of the oral cavity.

OBJECTIVE: The aim of this retrospective study was to report on the diagnostic accuracy of AgNOR-analysis as an adjunctive diagnostic tool of conventional oral exfoliative cytology taken from suspicious lesions in our clinic. STUDY DESIGN: Cytological diagnoses obtained from brush biopsies of macroscopically suspicious lesions of the oral mucosa from 75 patients (final diagnoses: 53 histologically proven squamous cell carcinomas, 11 leukoplakias and other inflammatory oral lesions) and from 11 patients with normal mucosa as a negative control group were compared with histological and/or clinical follow-ups. Five smears were doubtful and seven suspicious for tumor cells in the cytologic report. Number of AgNOR's were counted in 100 squamous epithelial cell-nuclei per slide after silver-restaining. RESULTS: Sensitivity of our cytological diagnosis alone on oral smears for the detection of squamous carcinomas was 92.5%, specificity 100%, positive predictive value was 100% and negative 84.6%. The best cut-off value of the mean number of AgNOR dots per nucleus distinguishing benign from malignant cells was 4.8. The percentage of nuclei with more than three AgNORs had a cut-off level of 70%. Applying these methods to twelve doubtful or suspicious cytological diagnoses we were able to correctly establish the diagnosis of malignancy in ten cases of histologically proven cancers and to reveal benignity in two histologically proven cases. Thus we achieved a positive and negative predictive value of 100% each. CONCLUSIONS: Smears from brushings of visible oral lesions, if clinically considered as suspicious for cancer, are an easily practicable, non-invasive, painless, safe and accurate screening method for detection of oral cancerous lesions. We conclude that AgNOR-analysis may be a useful adjunct to other methods in routine cytological diagnosis of oral cancer that can help to solve cytologically suspicious or doubtful cases.