Schizophrenia patients show impaired response switching in saccade tasks

Action control deficits of schizophrenia patients result from frontostriatal brain abnormalities and presumably reflect an impairment of selective cognitive processes. This study aimed at dissociating two different levels of action control in saccades toward and away from visual stimuli (pro- and antisaccades). Results of previous studies suggested that task switch effects (between pro- and antisaccades) reflect the persistence of a task-specific production rule and refer to the level of task selection, whereas response switch effects (between leftward and rightward saccades) point to the persistence of a specific response program, referring to the level of response selection. In the present study, task switching and response switching were investigated in 20 schizophrenia patients and 20 control subjects. Groups did not differ concerning task switch effects. In contrast, response switching entailed a stronger enhancement of error rates in patients, suggesting a specific deficit on the level of response selection in schizophrenia. The deficit was associated with spatial working memory capacities, confirming and specifying existing hypotheses on a relationship between working memory and action control.     

Visual and auditory emotion recognition problems as familial cross-disorder phenomenon in ASD and ADHD

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are frequently comorbid disorders. Emotion recognition problems are considered an important familial deficit in ASD, but this is unknown in ADHD. Very few studies have directly compared emotion recognition performance of youth with ASD and/or ADHD and of their unaffected siblings across age to quantify the contribution of emotion recognition problems to the ADHD phenotype. We therefore devised a study of 64 ASD+ADHD participants, 89 ASD-only participants, 111 ADHD-only participants, 122 unaffected ASD(+ADHD) siblings, 69 unaffected ADHD-only siblings and 220 controls aged 7–18 years, who had completed two tasks assessing auditory and visual emotion recognition. Factor analysis was used to detect underlying dimensions of emotion recognition capacity. Linear mixed models were used to compare performance across groups and to assess age effects. The factor-analysis revealed four factors separating speed and accuracy regarding visual and auditory emotion recognition. ASD+ADHD, ASD-only, and ADHD-only participants all performed worse than controls. ASD+ADHD, ASD-only, and ADHD-only participants did not differ in the severity of their emotion recognition problems. Both unaffected sibling groups performed intermediate between patients and controls. For ASD+ADHD and ADHD-only participants, group differences were more marked in adolescence than childhood, whereas in ASD participants this was not observed. We conclude that emotion recognition problems are a familial deficit in ADHD to a similar extent as in ASD. Emotion recognition problems specifically - and social cognition problems more generally - should be assessed in clinical practice for ADHD.     

Why do some trauma patients die while others survive? A matched-pair analysis based on data from Trauma Register DGU®

Purpose: The mortality rate for severely injured patients with the injury severity score (ISS) 16 has decreased in Germany. There is robust evidence that mortality is influenced not only by the acute trauma itself but also by physical health, age and sex. The aim of this study was to identify other possible influences on the mortality of severely injured patients. Methods: In a matched-pair analysis of data from Trauma Register DGU®, non-surviving patients from Germany between 2009 and 2014 with an ISS 16 were compared with surviving matching partners. Matching was performed on the basis of age, sex, physical health, injury pattern, trauma mechanism, conscious state at the scene of the accident based on the Glasgow coma scale, and the presence of shock on arrival at the emergency room. Results: We matched two homogeneous groups, each of which consisted of 657 patients (535 male, average age 37 years). There was no significant difference in the vital parameters at the scene of the accident, the length of the pre-hospital phase, the type of transport (ground or air), pre-hospital fluid management and amounts, ISS, initial care level, the length of the emergency room stay, the care received at night or from on-call personnel during the weekend, the use of abdominal sonographic imaging, the type of X-ray imaging used, and the percentage of patients who developed sepsis. We found a significant difference in the new injury severity score, the frequency of multi-organ failure, hemoglobine at admission, base excess and international normalized ratio in the emergency room, the type of accident (fall or road traffic accident), the pre-hospital intubation rate, reanimation, in-hospital fluid management, the frequency of transfusion, tomography (whole-body computed tomography), and the necessity of emergency intervention. Conclusion: Previously postulated factors such as the level of care and the length of the emergency room stay did not appear to have a significant influence in this study. Further studies should be conducted to analyse the identified factors with a view to optimising the treatment of severely injured patients. Our study shows that there are significant factors that can predict or influence the mortality of severely injured patients.     

Schuss- und Stichverletzungen in Deutschland – Epidemiologie und Outcome

Background

The management of gunshot wounds is a rare challenge for trauma surgeons in Germany and Central Europe as a result of the low incidence of this type of trauma. Penetrating injuries occur with an incidence of 5% in Germany. They are caused by gunshots or more commonly by knives or other objects, for example during accidents. Since even the number of patients who are treated at level 1 trauma centres is limited by the low incidence, the objective of this study was to assess the epidemiology and outcome of gunshot and stab wounds in Germany.

Material and methods

Since 2009, the trauma registry of the German Trauma Society (TraumaRegister DGU®) has been used to assess not only whether a trauma was penetrating but also whether it was caused by a gunshot or a stabbing. On the basis of this registry, we identified relevant cases and defined the observation period. Data were taken from the standard documentation forms that participating German hospitals completed between 2009 and 2011. We did not specify exclusion criteria in order to obtain as comprehensive a picture as possible of the trauma entities investigated in this study. As a result of the high incidence of gunshot wounds to the head and the implications of this type of injury for the entire group, a subgroup of patients without head injuries was analysed.

Results

From 2009 to 2011, there were 305 patients with gunshot wounds and 871 patients with stab wounds. The high proportion of suicide-related gunshot wounds to the head resulted in a cumulative mortality rate of 39.7%. Stab wounds were associated with a lower mortality rate (6.2%). Every fourth patient with a gunshot or stab wound presented with haemorrhagic shock, which was considerably more frequently seen during the prehospital phase than during the inhospital phase of patient management. Of the patients with gunshot wounds, 26.9% required transfusions. This percentage was three times higher than that for patients with blunt trauma.

Conclusion

In Germany, gunshot and stab wounds have a low incidence and are mostly caused by violent crime or attempted suicide. Depending on the site of injury, they have a high mortality and are often associated with major haemorrhage. As a result of the low incidence of these types of trauma, further data and analyses are required which can provide the basis for an evaluation of the long-term quality of the management of patients with stab or gunshot wounds.     

Development of a System for Additive Manufacturing of Ceramic Matrix Composite Structures Using Laser Technology

Ceramic matrix composites (CMCs) are refractory ceramic materials with damage-tolerant behavior. Coming from the space industry, this class of materials is increasingly being used in other applications, such as automotive construction for high-performance brake discs, furnace technology, heat coatings for pipe systems and landing flaps on reusable rocket sections. In order to produce CMC faster and more cost-efficiently for the increasing demand, a new additive manufacturing process is being tested, which in the future should also be able to realize material joints and higher component wall thicknesses than conventional processes. The main features of the process are as follows. A ceramic fiber bundle is de-sized and infiltrated with ceramic suspension. The bundle infiltrated with matrix material is dried and then applied to a body form. During application, the matrix material is melted by laser radiation without damaging the fiber material. For the initial validation of the material system, samples are pressed and analyzed for their absorption properties using integrating sphere measurement. With the results, a suitable processing laser is selected, and initial melting tests of the matrix system are carried out. After the first validation of the process, a test system is set up, and the first test specimens are produced to determine the material parameters.     

Synaptophysin: a marker protein for neuroendocrine cells and neoplasms.

Synaptophysin is an integral membrane glycoprotein (Mr 38,000) that occurs in presynaptic vesicles of neurons and in similar vesicles of the adrenal medulla. By using a monoclonal antibody to this protein (SY38), we have found, by immunohistochemistry and immunoblotting, that an identical or similar protein is also expressed in neuroendocrine tumors of neural type, such as pheochromocytomas and paragangliomas. In addition, this protein occurs in certain neuroendocrine epithelial cells, such as pancreatic islet cells; in a variety of neuroendocrine epithelial tumors, including isletcell adenomas and carcinomas and several carcinoids and neuroendocrine carcinomas of the gastrointestinal and the bronchial tracts; and in medullary carcinomas of the thyroid. Our results show that synaptophysin, and the vesicles that contain it, can occur in normal and neoplastic neuroendocrine cells of neural type, as demonstrated by colocalization with neurofilaments, as well as in those of epithelial type, as shown by colocalization with cytokeratin filaments and desmoplakins. We conclude that synaptophysin is expressed independently of other neuronal differentiation markers and propose that it be used as a differentiation marker in tumor diagnosis.     

Cell-based resurfacing of large cartilage defects: long-term evaluation of grafts from autologous transgene-activated periosteal cells in a porcine model of osteoarthritis

OBJECTIVE: To investigate the potential of transgene-activated periosteal cells for permanently resurfacing large partial-thickness cartilage defects. METHODS: In miniature pigs, autologous periosteal cells stimulated ex vivo by bone morphogenetic protein 2 gene transfer, using liposomes or a combination of adeno-associated virus (AAV) and adenovirus (Ad) vectors, were applied on a bioresorbable scaffold to chondral lesions comprising the entire medial half of the patella. The resulting repair tissue was assessed, 6 and 26 weeks after transplantation, by histochemical and immunohistochemical methods. The biomechanical properties of the repair tissue were characterized by nanoindentation measurements. Implants of unstimulated cells and untreated lesions served as controls. RESULTS: All grafts showed satisfactory integration into the preexisting cartilage. Six weeks after transplantation, AAV/Ad-stimulated periosteal cells had adopted a chondrocyte-like phenotype in all layers; the newly formed matrix was rich in proteoglycans and type II collagen, and its contact stiffness was close to that of healthy hyaline cartilage. Unstimulated periosteal cells and cells activated by liposomal gene transfer formed only fibrocartilaginous repair tissue with minor contact stiffness. However, within 6 months following transplantation, the AAV/Ad-stimulated cells in the superficial zone tended to dedifferentiate, as indicated by a switch from type II to type I collagen synthesis and reduced contact stiffness. In deeper zones, these cells retained their chondrocytic phenotype, coinciding with positive staining for type II collagen in the matrix. CONCLUSION: Large partial-thickness cartilage defects can be resurfaced efficiently with hyaline-like cartilage formed by transgene-activated periosteal cells. The long-term stability of the cartilage seems to depend on physicobiochemical factors that are active only in deeper zones of the cartilaginous tissue.     

Persistent vegetative state: evaluation of brain metabolism and brain perfusion with PET and SPECT

Patients in persistent vegetative state (PVS) after severe head trauma were investigated with 99mTc-ECD SPECT and 18F-FDG PET to further characterize the degree of brain damage and to obtain insight into changes of brain perfusion and glucose metabolism. 18F-FDG PET and 99mTc-ECD SPECT were performed in 16 patients in PVS. Quantitative PET data were compared with that obtained from seven normal controls. After spatial normalization into Talairach space, global grey matter values and regional data using predefined ROI sets were derived. For comparison of PET and SPECT, regional data were normalized to their individual mean grey matter values. Patients in PVS showed significantly lower values of cerebral glucose metabolism than did the controls. The mean reduction of grey matter values in cortical and subcortical structures was 58%, except in the vermis cerebelli, where only a reduction of 16% was found compared to the controls. Comparing the glucose metabolism and perfusion within the patient group, the pattern of both modalities was similar in the neocortex and internal ganglia. In the cerebellar hemispheres a relatively higher perfusion than glucose metabolism was found. The overall reduction of 58% of glucose metabolism in grey matter structures is in accordance with other PET studies investigating PVS patients with different disease histories. The relative preserved activity of vermis cerebelli seems to be an uncommon finding not described by other authors up to now.