[Retrospective Analysis of Diabetics with Regard to Treatment Duration and Costs]. / Retrospektive Analyse von Diabetikern im Hinblick auf Behandlungsdauer und Behandlungskosten in einem überregionalen Traumazentrum.

Background: The increasing incidence of diabetes mellitus is also reflected in the patient population of a trauma and orthopaedic centre. Diabetics also exhibit more comorbidities than non-diabetics. In addition to surgical problems in these patients, hospitalisation is often accompanied by complications, which can prolong treatment and increase costs. The aim of this retrospective study is to analyse hospitalisation of diabetics compared to non-diabetics, as well as differences in treatment costs, depending on associated age and comorbidities. Patients/Material and Methods: 17,185 patients were treated at a transregional trauma and orthopaedic centre and were included in this retrospective analysis between 2012 and 2015. Comorbidities and hospitalisation of diabetics and non-diabetics were recorded. All costs charged by DRG were evaluated to calculate the cost per day and per patient, on the basis of the specific case rate. In this calculation, patient-related case rates were divided by the average residence time and the means of the calculated daily rates were calculated. Inclusion criteria were treatment within the various departments and a minimum hospitalisation of one day. Statistical analysis was performed with the SPSS program (version 22.0, SPSS Inc., Chicago, USA). Results: In comparison to non-diabetics (ND), diabetics (D) exhibited significantly more comorbidities, including: obesity, arterial hypertension, coronary heart disease, myocardial infarction (in the history), peripheral arterial disease, chronic kidney disease and hyperlipidaemia. Pneumonia in hospital was considerably commoner in diabetics (2.45 % [D] vs. 1.02 % [ND], p < 0.001). Time in hospital was significantly longer in diabetics (endoprosthetics 13.52 days [D] vs. 12.54 days [ND], p < 0.001; septic surgery 18.62 days [D] vs. 16.31 days [ND], p = 0.007; traumatology 9.82 days [D] vs. 7.07 days [ND], p < 0.001). For patients aged under 60 years, time in hospital was significantly longer for diabetics than for non-diabetics (9.98 days [D] vs. 6.43 days [ND] p < 0.001). Because of the longer time in hospital, treatment costs were higher by € 1,932,929.42 during the investigated time period. Conclusion: Because of their comorbidities, diabetics need to be categorised at an early stage as high-risk patients in traumatological and orthopaedic departments. Hospitalisation and the associated increased treatment costs, as well as postoperative complications, could be minimised in patients with diabetes by implementing an interdisciplinary treatment concept.

Comparison of the electrophysiologically based optimization methods with different pacing parameters in patient undergoing resynchronization treatment.

Many studies conducted on patients suffering from congestive heart failure have shown the efficacy of cardiac resynchronization therapy (CRT). The presented research investigates an off-line optimization algorithm based on different electrode positioning and timing delays. A computer model of the heart was used to simulate left bundle branch block (LBBB), myocardial infarction (MI) and reduction of intraventricular conduction velocity in order to customize the patient symptom. The optimization method evaluates the error between the healthy heart and pathology with/without pacing in terms of activation time and QRS length. Additionally, a torso model of the patient is extracted to compute the body surface potential map (BSPM) and to simulate the ECG with Wilson leads to validate the results obtained by the electrophysiological heart model optimization.

Computer based optimization of biventricular pacing according to the left ventricular 17 myocardial segments.

Cardiac resynchronization therapy (CRT) has shown to improve hemodynamics and clinical symptoms of congestive heart failure. The present article investigates an automated non-invasive strategy based on a computer model of the heart to optimize biventricular pacing as a CRT with respect to electrode positioning and timing delays. Accurate simulations of the electrical activities of the heart require suitable anatomical and electrophysiological models. The anatomical model used in this work, is based on segmented MR data of a patient in which a variety of tissue classes for left ventricle are considered based on AHA standard in accordance with fiber orientation. The excitation propagation is simulated with the ten Tusscher et al. electrophysiological cell model using an adaptive cellular automaton. The simulated activation times of different myocytes in the healthy and diseased heart model are compared in terms of root mean square error (ERMS). The results of our investigation demonstrate that the efficacy of biventricular pacing can greatly be improved by proper electrode positioning and optimized A-V and V-V delay.

[TGF-beta1 as a pathophysiological factor in fracture healing]. / TGF-beta1 als pathophysiologischer Faktor bei der Frakturheilung.

AIM: TGF-beta1 is an important local and systemic regulatory molecule during fracture healing. Various authors have shown differences in the systemic levels of TGF-beta1 over the time taken for bone healing in distraction osteogenesis and osteotomies. Previous studies have shown characteristic differences in the physiological levels of growth factors between normal fracture healing and delayed fracture union. The aim of the present study was to evaluate possible differences in sera levels of patients with normal and delayed union fracture healing. METHODS: Patients with long bone shaft fractures were recruited prospectively. Peripheral blood samples were collected over a period of 1 year using a standardized time schedule. At the end of the individual's investigation period, TGF-beta1 levels were determined. To achieve a homogeneous collective of patients, only those with a maximum of two fractures were included in the study. After matching for four criteria, we compared patients with normal fracture healing to patients with delayed unions. The fact of delayed union was accepted in case of failed consolidation 4 months after trauma. RESULTS: During a prospective study period of 1 year, 15 patients with normal fracture healing could be compared to 15 patients suffering from delayed union. By determining the absolute sera levels we found a typical increase of TGF-beta1 up to 2 weeks after fracture in both groups, with a subsequent decrease up to the sixth week after fracture. However, a decline in serum concentration occurred earlier in patients with delayed union, causing significantly lower TGF-beta1 levels in the non-union group 4 weeks after trauma (P=0.00006). CONCLUSION: Even with a relatively small number of patients, we could show a significant difference in serum concentrations of TGF-beta1 between the investigated groups. If these results can be verified within a larger collective, TGF-beta1 could be used as a predictive cytokine for delayed fracture healing.

Simulating pulmonary vein activity leading to atrial fibrillation using a rule-based approach on realistic anatomical data.

Atrial fibrillation (AF) is the most common cardiac arrhythmia leading to a high rate of stroke. The underlying mechanisms of initiation and maintenance of AF are not fully understood. Several findings suggest a multitude of factors to leave the atria vulnerable to AF. In this work, a rule-based approach is taken to simulate the initiation of AF in a computer model for the purpose of generating a model with which the influence of anatomical structures, electrophysiological properties of the atria and arrhythmogenic activity can be evaluated. Pulmonary vein firing has been simulated leading to AF in 65.7 % of all simulations. The excitation pattern generated resemble chaotic excitation behavior, which is characteristic for AF as well as stable reentrant circuits responsible for atrial flutter. The findings compare well with literature. In future, the presented computer model of AF can be used in therapy planning such as ablation therapy or overdrive pacing.

Notions of heredity in the correspondence of Edwin Grant Conklin.

This article examines five letters from the correspondence of American zoologist Edwin Grant Conklin that highlight his theories of genetic and social inheritance, in order to suggest that Conklin's eugenic beliefs--like those of many American authorities during this time--were complex and sometimes contradictory. The letters reveal the international prestige of American science after the two world wars and illuminate key moments in the emergence of the concepts of heredity and inheritance, within both the science of genetics and the social movement of eugenics.

Dissociation of motor preparation from memory and attentional processes using movement-related cortical potentials.

The EEG activity preceding self-paced voluntary movements (movement-related cortical potential, MRCP) is smaller if subjects make the same movement each time (regular task) compared with when different movements are made each time (random task). To test whether extra activity in the random task is due to increased motor preparation needed to switch between different movements, or to memory/attentional processes needed to select movements randomly, we compared regular and random movements with an additional alternating task. This alternating task required subjects to make different movements each time as in the random task, but since the task was very simple, the memory/attentional load was similar to that in the regular task. The MRCP was equally large over motor areas in both random and alternating tasks, suggesting that the extra activity over sensorimotor areas reflected processes involved in motor preparation rather than memory/attention. We speculate that, in the regular task, some part of the instructions for the previous movement remains intact, reducing the amount of preparation needed for the next repetition. Thus the MRCP is smaller than in the alternating and random tasks. Although the MRCPs in alternating and random tasks were similar over the motor areas, the random task had more activity than the alternating task in contralateral frontal areas. This part of the MRCP may therefore be related to memory/attentional processes required to randomize the sequence of movements. We conclude that the MRCP contains dissociable components related to motor preparation and memory/attention.