[Symptomatic hyponatremia in a 43-year-old woman after a skiing accident with head injuries]

This article reports the case of a 43-year-old woman who presented to the emergency room with headache and paresthesia after a fall on the head while skiing. She had clinical signs of volume depletion and blood test showed severe hyponatremia. Cerebral imaging was unremarkable. The diagnosis of cerebral salt-wasting syndrome (CSWS) was made, which is defined by the presence of extracellular volume depletion due to a tubular defect in renal sodium transport in patients with normal adrenal and thyroid function. The disease is mostly secondary to a neurological disease or head trauma. The patient rapidly improved after volume therapy and treatment with mineralocorticoids. The differentiation of CSWS from the syndrome of inappropriate antidiuretic hormone (SIADH) secretion can be challenging but the distinction is important because treatment options are very different.

Surface Activity Profiling (SAP): A potential means of predicting intestinal membrane permeability

Early characterization of new drug substances intended for oral application includes not only physicochemical properties and stability but also the ability of the substance to permeate through the intestinal mucosa. In this work, a rapid screening method, surface activity profiling (SAP), is proposed as an alternative to animal studies and screening in cell cultures. Measurements are made with a multichannel tensiometer and require only 50 µl of stock solution for the complete permeability analysis. Correlation of SAP results with human absorption was demonstrated for marketed drugs and with absorption in rats for development compounds of Boehringer Ingelheim. Cross-laboratory results for marketed drugs showed excellent agreement. For early stage investigations of lead compounds, where only small amounts of the compound are available, the SAP method appears to be an effective and fast tool to accurately predict fa, provided the compound is amphiphilic.

Neurophysiological evidence of impaired attention and working memory in untreated hematologic cancer patients

OBJECTIVE

Neuroimaging studies of hematologic cancer patients report altered activity in dorsal attention and central executive networks. To determine the consequences of these altered brain networks, we evaluated neurophysiological correlates of attention and working memory in hematologic cancer patients prior to initiating treatment.

METHODS

Hematologic cancer patients (19-80 years) were excluded for premorbid cognitive impairment, prior non-hematologic cancer diagnosis, and prior chemotherapy. Attention was manipulated by presenting an irrelevant spatial cue prior to visual search displays. Working memory was manipulated by presenting irrelevant distractors within memory displays. Electroencephalogram was recorded during task performance.

RESULTS

Patients (n = 28) and controls (n = 15) were balanced on age, gender, and education. Spatial cues evoked larger N2pc amplitudes, a correlate of spatial attention, in patients than controls (p < .05; Cohen's d > 0.7). Memory distractors evoked larger contralateral delay activity amplitudes, a correlate of working memory load, in patients (p = .028; Cohen's d = 1.1) but not controls (p = .64).

CONCLUSIONS

Prior to initiating treatment, hematologic cancer patients demonstrated poor control over spatial attention and working memory, consistent with altered dorsal attention and central executive network activity.

SIGNIFICANCE

Hematologic cancer patients may be at a higher risk for selecting, processing, and storing distracting information that would compete with more immediate goal-related behaviors.

SIESTA: A high current ion source for erosion and retention studies

Second ion experiment for sputtering and TDS analysis is a high-current ion source for erosion and retention studies with focus on wall materials for fusion devices. The system is composed of a DuoPIGatron type ion source, three consecutive grids for ion extraction, acceleration and beam focusing, a differential pumping stage, a dipole magnet for mass filtering, a quadrupole doublet lens, a target chamber, a load-lock, and a chamber for thermal desorption spectrometry. The acceleration potential of the source can be varied between 500 V and 10 kV. The target chamber has a base pressure of 10^-8 mbar and an operating pressure of 5 × 10^-7 mbar. The target can be rotated to study angle-dependent effects and can be heated via electron-impact heating up to 1300 K for high temperature erosion and implantation studies. The target chamber is equipped with an in situ magnetic suspension balance. The operating parameters of the ion source were mapped to achieve the maximum ion current at the target for various gas species and accelerating potentials. The beam emittance for a D₃ ⁺ ion beam was measured after deflection in the dipole magnet. This was used for ion beam simulations, which were instrumental for the design of the quadrupole lenses. If the quadrupole doublet is used, the ion flux to the target is increased by up to a factor of 4. Additionally, the relative population of neutral particles present in the beam at the target was quantified and is equal to 0.8% when averaged over the measurement positions. The typical beam footprint at the target under normal incidence has an area of 0.5 cm². The ion current reaching the target increases with the accelerating potential. Due to this effect, the ion flux density at the target in the low-ion-impact-energy range can be increased by operating the source at a higher extraction potential and by applying a (decelerating) potential to the target. Ion impact energies as low as 200 eV/D are achieved this way with a D₃ ⁺ current of 100 μA when focusing the beam with the quadrupole doublet lens, equating to a D particle flux density of 3.7 × 10¹⁹ m^-2 s^-1. At ion impact energies of 2 keV/D, the maximum achievable flux density with D₃ ⁺ is 6 × 10¹⁹ D m^-2 s^-1. Experimental determination of sputter yields was performed via ex situ weight loss measurement for bulk Au samples, showing reasonably good agreement with simulations and experimental data from the literature.

Abstract PD3-02: Comparison of HER2, estrogen and progesterone receptor expression profiles of primary tumor, synchronous axillary lymph node metastases and circulating tumor cells in early breast cancer patients

Background:Targeted systemic therapy in early breast cancer with synchronous lymph node metastasis is currently based on the expression of the hormone receptors (ER/PR ≥1%) and overexpression of HER2 in the primary tumor. However, the expression of these predictive markers on lymph node metastases as well as on circulating tumor cells (CTCs), the precursors of metastatic disease, has not yet been taken into account. The aim of the present study was to compare the HER2/ER/PR expression profiles of primary tumors, synchronous lymph node metastases and circulating tumor cells in early breast cancer patients and relate the results to 5-year overall (OS) and disease-free survival (DFS).

Patients and Methods:76 patients with early breast cancer diagnosed between 2006 and 2010 were enrolled in this study. Blood was obtained at the time of first diagnosis of disease and analyzed for CTCs using the AdnaTest BreastCancer (Qiagen Hannover GmbH) for the expression of EpCAM, MUC-1, HER2, ER and PR respectively.

Formalin-fixed and paraffin-embedded archival tissues of the primary tumors and the lymph node metastases were analyzed by two pathologists. ER, PR and HER2 expression was assessed by fully-automated immunohistochemistry (Ventana medical Systems, USA) and HER2/CEN17 dual chromogenic in situ hybridization (Zytomed Systems, Germany) according to modified ASCO/CAP guidelines (2010 and 2013).

The patients' cohort has been extended for the time period of 2010-2012.

Results: 2006-2010 the detection rate for CTCs was 22% (17/76 patients). In the primary tumors, the expression rate of HER2 was 16% (13/76 patients), 78% for ER (61/76 patients) and 75% for PR (57/76 patients) respectively. Changes in biomarker profiles between primary tumors, metastases and CTCs, as a whole, were observed in 89% of the cases (68/76). The discordance rates between primary tumors and lymph node metastases were 10% for HER2 (p&lt;0.001), 5% for ER (p=p&lt;0.001) and 11% for PR (p&lt;0.001). The intrinsic subtypes between primary tumors and lymph node metastases changed in 16% of all cases (12/76 patients; gain of HER2 in four, activation of HRs in three cases, loss of HER2 in three and loss of HRs in one case becoming triple negative). Of note, both OS and DFS of patients with subtype discordance were reduced to a median of 41 months (mean:39) vs 56 months (mean:51).

CTCs were either triple negative or HER2 positive. Discordance rates for HER2, ER and PR status compared to the primary tumors were 16% (12/76 patients), 83% (63/76 patients)and 72% (55/76 patients), respectively. Discordant rates between lymph node metastases and CTCs were 25% for HER2 (19/76 patients), 82% for ER (62/76 patients) and 72% for PR (55/76 patients).

Enlarged results including the cohort 2010-2012 will be available for SABCS 2017.

Conclusion: Our preliminarily results demonstrate, that changes in molecular profiles are the rule rather than the exception throughout tumor progression in breast cancer. In cases with discordant biomarker profiles, prognosis seems to follow the subtype of lymph node metastasis. Biomarker or subtype shift may be of essential therapeutic significance for individual patients.

Citation Format: Aktas B, Weydandt L, Westerwick D, Mairinger F, Kasimir-Bauer S, Kimmig R, Schmid K, Bankfalvi A. Comparison of HER2, estrogen and progesterone receptor expression profiles of primary tumor, synchronous axillary lymph node metastases and circulating tumor cells in early breast cancer patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD3-02.

Abstract P1-01-09: Comparison of HER2, estrogen and progesterone receptor expression profiles of primary tumor, synchronous axillary lymph node metastases and circulating tumor cells in early breast cancer patients

Background:Targeted systemic therapy in early breast cancer with synchronous lymph node metastasis is currently based on the expression of the hormone receptors (ER/PR ≥1%) and overexpression of HER2 in the primary tumor. However, the expression of these predictive markers on lymph node metastases as well as on circulating tumor cells (CTCs), the precursors of metastatic disease, has not yet been taken into account. The aim of the present study was to compare the HER2/ER/PR expression profiles of primary tumors, synchronous lymph node metastases and circulating tumor cells in early breast cancer patients and relate the results to 5-year overall (OS) and disease-free survival (DFS).

Patients and Methods:76 patients with early breast cancer diagnosed between 2006 and 2010 were enrolled in this study. Blood was obtained at the time of first diagnosis of disease and analyzed for CTCs using the AdnaTest BreastCancer (Qiagen Hannover GmbH) for the expression of EpCAM, MUC-1, HER2, ER and PR respectively.

Formalin-fixed and paraffin-embedded archival tissues of the primary tumors and the lymph node metastases were analyzed by two pathologists. ER, PR and HER2 expression was assessed by fully-automated immunohistochemistry (Ventana medical Systems, Tucson, AZ, USA) and HER2/CEN17 dual chromogenic in situ hybridization (Zytomed Systems, Berlin, Germany) according to modified ASCO/CAP guidelines (2010 and 2013, respectively).

Results: The detection rate for CTCs was 22% (17/76 patients). In the primary tumors, the expression rate of HER2 was 16% (13/76 patients), 78% for ER (61/76 patients) and 75% for PR (57/76 patients) respectively. Changes in biomarker profiles between primary tumors, metastases and CTCs, as a whole, were observed in 89% of the cases (68/76). The discordance rates between primary tumors and lymph node metastases were 10% for HER2 (p&lt;0.001), 5% for ER (p= p&lt;0.001) and 11% for PR (p&lt;0.001). The intrinsic subtypes between primary tumors and lymph node metastases changed in 16% of all cases (12/76 patients; gain of HER2 in four, activation of HRs in three cases, loss of HER2 in three and loss of HRs in one case becoming triple negative). Of note, both OS and DFS of patients with subtype discordance were reduced to a median of 41 months (mean: 39) vs 56 months (mean: 51).

CTCs were either triple negative or HER2 positive. Discordance rates for HER2, ER and PR status compared to the primary tumors were 16% (12/76 patients), 83% (63/76 patients)and 72% (55/76 patients), respectively. Discordant rates between lymph node metastases and CTCs were 25% for HER2 (19/76 patients), 82% for ER (62/76 patients) and 72% for PR (55/76 patients).

Conclusion: Our preliminarily results demonstrate, that changes in molecular profiles are the rule rather than the exception throughout tumour progression in breast cancer. In cases with discordant biomarker profiles, prognosis seems to follow the subtype of lymph node metastasis. Biomarker or subtype shift may be of essential therapeutic significance for individual patients.

Citation Format: Aktas B, Westerwick D, Mairinger F, Kasimir-Bauer S, Kimmig R, Schmid K, Bankfalvi A. Comparison of HER2, estrogen and progesterone receptor expression profiles of primary tumor, synchronous axillary lymph node metastases and circulating tumor cells in early breast cancer patients [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-01-09.

Ability of Serum Glial Fibrillary Acidic Protein, Ubiquitin C-Terminal Hydrolase-L1, and S100B To Differentiate Normal and Abnormal Head Computed Tomography Findings in Patients with Suspected Mild or Moderate Traumatic Brain Injury

Head computed tomography (CT) imaging is still a commonly obtained diagnostic test for patients with minor head injury despite availability of clinical decision rules to guide imaging use and recommendations to reduce radiation exposure resulting from unnecessary imaging. This prospective multicenter observational study of 251 patients with suspected mild to moderate traumatic brain injury (TBI) evaluated three serum biomarkers' (glial fibrillary acidic protein [GFAP], ubiquitin C-terminal hydrolase-L1 [UCH-L1] and S100B measured within 6 h of injury) ability to differentiate CT negative and CT positive findings. Of the 251 patients, 60.2% were male and 225 (89.6%) had a presenting Glasgow Coma Scale score of 15. A positive head CT (intracranial injury) was found in 36 (14.3%). UCH-L1 was 100% sensitive and 39% specific at a cutoff value >40 pg/mL. To retain 100% sensitivity, GFAP was 0% specific (cutoff value 0 pg/mL) and S100B had a specificity of only 2% (cutoff value 30 pg/mL). All three biomarkers had similar values for areas under the receiver operator characteristic curve: 0.79 (95% confidence interval; 0.70–0.88) for GFAP, 0.80 (0.71–0.89) for UCH-L1, and 0.75 (0.65–0.85) for S100B. Neither GFAP nor UCH-L1 curve values differed significantly from S100B (p = 0.21 and p = 0.77, respectively). In our patient cohort, UCH-L1 outperformed GFAP and S100B when the goal was to reduce CT use without sacrificing sensitivity. UCH-L1 values <40 pg/mL could potentially have aided in eliminating 83 of the 215 negative CT scans. These results require replication in other studies before the test is used in actual clinical practice.

Obesity in Youth with Type 1 Diabetes in Germany, Austria, and the United States

OBJECTIVE

To examine the current extent of the obesity problem in 2 large pediatric clinical registries in the US and Europe and to examine the hypotheses that increased body mass index (BMI) z-scores (BMIz) are associated with greater hemoglobin A1c (HbA1c) and increased frequency of severe hypoglycemia in youth with type 1 diabetes (T1D).

STUDY DESIGN

International (World Health Organization) and national (Centers for Disease Control and Prevention/German Health Interview and Examination Survey for Children and Adolescents) BMI references were used to calculate BMIz in participants (age 2-<18 years and ≥ 1 year duration of T1D) enrolled in the T1D Exchange (n = 11,435) and the Diabetes Prospective Follow-up (n = 21,501). Associations between BMIz and HbA1c and severe hypoglycemia were assessed.

RESULTS

Participants in both registries had median BMI values that were greater than international and their respective national reference values. BMIz was significantly greater in the T1D Exchange vs the Diabetes Prospective Follow-up (P < .001). After stratification by age-group, no differences in BMI between registries existed for children 2-5 years, but differences were confirmed for 6- to 9-, 10- to 13-, and 14- to 17-year age groups (all P < .001). Greater BMIz were significantly related to greater HbA1c levels and more frequent occurrence of severe hypoglycemia across the registries, although these associations may not be clinically relevant.

CONCLUSIONS

Excessive weight is a common problem in children with T1D in Germany and Austria and, especially, in the US. Our data suggest that obesity contributes to the challenges in achieving optimal glycemic control in children and adolescents with T1D.

Proposal for a clinical-dermoscopic classification of scalp naevi

BACKGROUND

Recent research suggests that scalp naevi differ with respect to their epidemiology, patient characteristics and morphological patterns, but currently a classification of scalp naevi is lacking.

OBJECTIVES

To investigate the prevalence, together with clinical and dermoscopic features, of scalp naevi detected in persons attending a skin cancer screening programme, and to elaborate a classification of scalp naevi based on their most common morphological patterns.

METHODS

Participants were recruited during the melanoma prevention programme 'sun watch' of Austrian Cancer Aid in Styria. Each participant received a clinical and dermoscopic total-body skin examination including the scalp. For each participant, demographics and clinical characteristics including number of scalp naevi were recorded. Clinical and dermoscopic photographs of at least one scalp naevus per participant were taken and evaluated for specific clinical and dermoscopic features.

RESULTS

In total 867 subjects, including 119 participants (13·7%) with scalp naevi, participated in the study. Compared with those without scalp naevi, subjects with scalp naevi were significantly younger, were more often men and more often exhibited congenital naevi on the body (P < 0·01 for all). Analysis of the clinical and dermoscopic variability of scalp naevi allowed for a proposal to classify scalp naevi into six main groups, namely common, papillomatous, eclipse, congenital, blue and atypical naevus.

CONCLUSIONS

Scalp naevi can be classified into six morphological groups; scalp lesions deviating from these six main patterns should be carefully managed to rule out melanoma.

Minor and repetitive head injury

Traumatic brain injury (TBI) is the leading cause of death and disability in the young, active population and expected to be the third leading cause of death in the whole world until 2020. The disease is frequently referred to as the silent epidemic, and many authors highlight the "unmet medical need" associated with TBI.The term traumatically evoked brain injury covers a heterogeneous group ranging from mild/minor/minimal to severe/non-salvageable damages. Severe TBI has long been recognized to be a major socioeconomical health-care issue as saving young lives and sometimes entirely restituting health with a timely intervention can indeed be extremely cost efficient.Recently it has been recognized that mild or minor TBI should be considered similarly important because of the magnitude of the patient population affected. Other reasons behind this recognition are the association of mild head injury with transient cognitive disturbances as well as long-term sequelae primarily linked to repeat (sport-related) injuries.The incidence of TBI in developed countries can be as high as 2-300/100,000 inhabitants; however, if we consider the injury pyramid, it turns out that severe and moderate TBI represents only 25-30 % of all cases, while the overwhelming majority of TBI cases consists of mild head injury. On top of that, or at the base of the pyramid, are the cases that never show up at the ER - the unreported injuries.Special attention is turned to mild TBI as in recent military conflicts it is recognized as "signature injury."This chapter aims to summarize the most important features of mild and repetitive traumatic brain injury providing definitions, stratifications, and triage options while also focusing on contemporary knowledge gathered by imaging and biomarker research.Mild traumatic brain injury is an enigmatic lesion; the classification, significance, and its consequences are all far less defined and explored than in more severe forms of brain injury.Understanding the pathobiology and pathomechanisms may aid a more targeted approach in triage as well as selection of cases with possible late complications while also identifying the target patient population where preventive measures and therapeutic tools should be applied in an attempt to avoid secondary brain injury and late complications.

A systems biology strategy to identify molecular mechanisms of action and protein indicators of traumatic brain injury

The multifactorial nature of traumatic brain injury (TBI), especially the complex secondary tissue injury involving intertwined networks of molecular pathways that mediate cellular behavior, has confounded attempts to elucidate the pathology underlying the progression of TBI. Here, systems biology strategies are exploited to identify novel molecular mechanisms and protein indicators of brain injury. To this end, we performed a meta-analysis of four distinct high-throughput gene expression studies involving different animal models of TBI. By using canonical pathways and a large human protein-interaction network as a scaffold, we separately overlaid the gene expression data from each study to identify molecular signatures that were conserved across the different studies. At 24 hr after injury, the significantly activated molecular signatures were nonspecific to TBI, whereas the significantly suppressed molecular signatures were specific to the nervous system. In particular, we identified a suppressed subnetwork consisting of 58 highly interacting, coregulated proteins associated with synaptic function. We selected three proteins from this subnetwork, postsynaptic density protein 95, nitric oxide synthase 1, and disrupted in schizophrenia 1, and hypothesized that their abundance would be significantly reduced after TBI. In a penetrating ballistic-like brain injury rat model of severe TBI, Western blot analysis confirmed our hypothesis. In addition, our analysis recovered 12 previously identified protein biomarkers of TBI. The results suggest that systems biology may provide an efficient, high-yield approach to generate testable hypotheses that can be experimentally validated to identify novel mechanisms of action and molecular indicators of TBI.

Teaching dermatoscopy of pigmented skin tumours to novices: comparison of analytic vs. heuristic approach

BACKGROUND

There are two strategies to approach the dermatoscopic diagnosis of pigmented skin tumours, namely the verbal-based analytic and the more visual-global heuristic method. It is not known if one or the other is more efficient in teaching dermatoscopy.

OBJECTIVE

To compare two teaching methods in short-term training of dermatoscopy to medical students.

METHODS

Fifty-seven medical students in the last year of the curriculum were given a 1-h lecture of either the heuristic- or the analytic-based teaching of dermatoscopy. Before and after this session, they were shown the same 50 lesions and asked to diagnose them and rate for chance of malignancy. Test lesions consisted of melanomas, basal cell carcinomas, nevi, seborrhoeic keratoses, benign vascular tumours and dermatofibromas. Performance measures were diagnostic accuracy regarding malignancy as measured by the area under the curves of receiver operating curves (range: 0-1), as well as per cent correct diagnoses (range: 0-100%).

RESULTS

Diagnostic accuracy as well as per cent correct diagnoses increased by +0.21 and +32.9% (heuristic teaching) and +0.19 and +35.7% (analytic teaching) respectively (P for all <0.001). Neither for diagnostic accuracy (P = 0.585), nor for per cent correct diagnoses (P = 0.298) was a difference between the two groups.

CONCLUSIONS

Short-term training of dermatoscopy to medical students allows significant improvement in diagnostic abilities. Choosing a heuristic or analytic method does not have an influence on this effect in short training using common pigmented skin lesions.

Human traumatic brain injury induces autoantibody response against glial fibrillary acidic protein and its breakdown products

The role of systemic autoimmunity in human traumatic brain injury (TBI) and other forms of brain injuries is recognized but not well understood. In this study, a systematic investigation was performed to identify serum autoantibody responses to brain-specific proteins after TBI in humans. TBI autoantibodies showed predominant immunoreactivity against a cluster of bands from 38-50 kDa on human brain immunoblots, which were identified as GFAP and GFAP breakdown products. GFAP autoantibody levels increased by 7 days after injury, and were of the IgG subtype predominantly. Results from in vitro tests and rat TBI experiments also indicated that calpain was responsible for removing the amino and carboxyl termini of GFAP to yield a 38 kDa fragment. Additionally, TBI autoantibody staining co-localized with GFAP in injured rat brain and in primary rat astrocytes. These results suggest that GFAP breakdown products persist within degenerating astrocytes in the brain. Anti-GFAP autoantibody also can enter living astroglia cells in culture and its presence appears to compromise glial cell health. TBI patients showed an average 3.77 fold increase in anti-GFAP autoantibody levels from early (0-1 days) to late (7-10 days) times post injury. Changes in autoantibody levels were negatively correlated with outcome as measured by GOS-E score at 6 months, suggesting that TBI patients with greater anti-GFAP immune-responses had worse outcomes. Due to the long lasting nature of IgG, a test to detect anti-GFAP autoantibodies is likely to prolong the temporal window for assessment of brain damage in human patients.

Systems biology approaches for discovering biomarkers for traumatic brain injury

The rate of traumatic brain injury (TBI) in service members with wartime injuries has risen rapidly in recent years, and complex, variable links have emerged between TBI and long-term neurological disorders. The multifactorial nature of TBI secondary cellular response has confounded attempts to find cellular biomarkers for its diagnosis and prognosis or for guiding therapy for brain injury. One possibility is to apply emerging systems biology strategies to holistically probe and analyze the complex interweaving molecular pathways and networks that mediate the secondary cellular response through computational models that integrate these diverse data sets. Here, we review available systems biology strategies, databases, and tools. In addition, we describe opportunities for applying this methodology to existing TBI data sets to identify new biomarker candidates and gain insights about the underlying molecular mechanisms of TBI response. As an exemplar, we apply network and pathway analysis to a manually compiled list of 32 protein biomarker candidates from the literature, recover known TBI-related mechanisms, and generate hypothetical new biomarker candidates.

The challenge of mild traumatic brain injury: role of biochemical markers in diagnosis of brain damage

During the past decade there has been an increasing recognition of the incidence of mild traumatic brain injury (mTBI) and a better understanding of the subtle neurological and cognitive deficits that may result from it. A substantial, albeit suboptimal, effort has been made to define diagnostic criteria for mTBI and improve diagnostic accuracy. Thus, biomarkers that can accurately and objectively detect brain injury after mTBI and, ideally, aid in clinical management are needed. In this review, we discuss the current research on serum biomarkers for mTBI including their rationale and diagnostic performances. Sensitive and specific biomarkers reflecting brain injury can provide important information regarding TBI pathophysiology and serve as candidate markers for predicting abnormal computed tomography findings and/or the development of residual deficits in patients who sustain an mTBI. We also outline the roles of biomarkers in settings of specific interest including pediatric TBI, sports concussions and military injuries, and provide perspectives on the validation of such markers for use in the clinic. Finally, emerging proteomics-based strategies for identifying novel markers will be discussed.

Shock-front injector for high-quality laser-plasma acceleration

We report the generation of stable and tunable electron bunches with very low absolute energy spread (ΔE ≈ 5 MeV) accelerated in laser wakefields via injection and trapping at a sharp downward density jump produced by a shock front in a supersonic gas flow. The peak of the highly stable and reproducible electron energy spectrum was tuned over more than 1 order of magnitude, containing a charge of 1-100 pC and a charge per energy interval of more than 10 pC/MeV. Laser-plasma electron acceleration with Ti:sapphire lasers using this novel injection mechanism provides high-quality electron bunches tailored for applications.

Analysis of the human immune response to vaccinia by use of a novel protein microarray suggests that antibodies recognize less than 10% of the total viral proteome

Control of smallpox by mass vaccination was one of the most effective public health measures ever employed for eradicating a devastating infectious disease. However, new methods are needed for monitoring smallpox immunity within current vulnerable populations, and for the development of replacement vaccines for use by immunocompromized or low-responding individuals. As a measure for achieving this goal, we developed a protein microarray of the vaccinia virus proteome by using high-throughput baculovirus expression and purification of individual elements. The array was validated with therapeutic-grade, human hyperimmune sera, and these data were compared to results obtained from individuals vaccinated against smallpox using Dryvax. A high level of reproducibility with a very low background were apparent in repetitive assays that confirmed previously reported antigens and identified new proteins that may be important for neutralizing viral infection. Our results suggest that proteins recognized by antibodies from all vaccinees constituted <10% of the total vaccinia proteome.

Glial neuronal ratio: a novel index for differentiating injury type in patients with severe traumatic brain injury

Neurobiochemical marker levels in blood after traumatic brain injury (TBI) may reflect structural changes detected by neuroimaging. This study evaluates whether correlations between neuronal (ubiquitin carboxy-terminal hydrolase-L1 [UCH-L1]) and glial (glial fibrillary acidic protein [GFAP]) biomarkers may be used as an indicator for differing intracranial pathologies after brain trauma. In 59 patients with severe TBI (Glasgow Coma Scale [GCS] score≤8) serum samples were obtained at the time of hospital admission and analyzed for UCH-L1 and GFAP. Glial neuronal ratio (GNR) was evaluated as the ratio between GFAP and UCH-L1 concentrations. A logistic regression analysis was used to identify variables associated with type of injury. GNR had a median of 0.85 and was positively correlated with age (R=0.45, p=0.003). Twenty-nine patients presented with diffuse injury and 30 with focal mass lesions as assessed by CT scan at admission and classified according to the Marshall Classification. GNR was significantly higher in the focal mass lesion group compared with the diffuse injury group (1.77 versus 0.48, respectively; p=0.003). Receiver operating characteristic curve analysis showed that GNR discriminated between types of injury (area under the curve [AUC]=0.72; p=0.003). GNR was more accurate earlier (≤12 h after injury) than later (AUC=0.80; p=0.002). Increased GNR was independently associated with type of injury, but not age, gender, GCS score, or mechanism of injury. GNR was significantly higher in patients who died, but was not an independent predictor of death. The data from the present study indicate that GNR provides valuable information about different injury pathways, which may be of diagnostic significance. In addition, GNR may help to identify different pathophysiological mechanisms following different types of brain trauma, with implications for therapeutic interventions.

Increased levels of serum MAP-2 at 6-months correlate with improved outcome in survivors of severe traumatic brain injury

OBJECTIVE

To evaluate microtubule-associated proteins (MAP-2), a dendritic marker of both acute damage and chronic neuronal regeneration after injury, in serum of survivors after severe TBI and examine the association with long-term outcome.

METHODS

Serum concentrations of MAP-2 were evaluated in 16 patients with severe TBI (Glasgow Coma Scale score [GCS] ≤ 8) 6 months post-injury and in 16 controls. Physical and cognitive outcomes were assessed, using the Glasgow Outcome Scale Extended (GOSE) and Levels of Cognitive Functioning Scale (LCFS), respectively.

RESULTS

Severe TBI patients had significantly higher serum MAP-2 concentrations than normal controls with no history of TBI (p = 0.008) at 6 months post-injury. MAP-2 levels correlated with the GOSE (r = 0.58, p = 0.02) and LCFS (r = 0.65, p = 0.007) at month 6. Significantly lower serum levels of MAP-2 were observed in patients in a vegetative state (VS) compared to non-VS patients (p < 0.05). A trend tracking the level of consciousness was observed.

CONCLUSIONS

Severe TBI results in a chronic release of MAP-2 into the peripheral circulation in patients with higher levels of consciousness, suggesting that remodelling of synaptic junctions and neuroplasticity processes occur several months after injury. The data indicate MAP-2 as a potential marker for emergence to higher levels of cognitive function.

Few-cycle driven relativistically oscillating plasma mirrors: a source of intense isolated attosecond pulses

The conditions required for the production of isolated attosecond pulses from relativistically oscillating mirrors (ROM) are investigated numerically and experimentally. In simulations, carrier-envelope-phase-stabilized three-cycle pulses are found to be sufficient to produce isolated attosecond pulses, while two-cycle pulses will predominantly lead to isolated attosecond pulses even in the absence of carrier-envelope stabilization. Using a state-of-the-art laser system delivering three-cycle pulses at multiple-terawatt level, we have generated higher harmonics up to 70 eV photon energy via the ROM mechanism. The observed spectra are in agreement with theoretical expectations and highlight the potential of few-cycle-driven ROM harmonics for intense isolated attosecond pulse generation for performing extreme ultraviolet-pump extreme ultraviolet-probe experiments.

Supersonic gas jets for laser-plasma experiments

We present an in-depth analysis of De Laval nozzles, which are ideal for gas jet generation in a wide variety of experiments. Scaling behavior of parameters especially relevant to laser-plasma experiments as jet collimation, sharpness of the jet edges and Mach number of the resulting jet is studied and several scaling laws are given. Special attention is paid to the problem of the generation of microscopic supersonic jets with diameters as small as 150 μm. In this regime, boundary layers dominate the flow formation and have to be included in the analysis.

Brain injury biomarkers may improve the predictive power of the IMPACT outcome calculator

Outcome prediction following severe traumatic brain injury (sTBI) is a widely investigated field of research. A major breakthrough is represented by the IMPACT prognostic calculator based on admission data of more than 8500 patients. A growing body of scientific evidence has shown that clinically meaningful biomarkers, including glial fibrillary acidic protein (GFAP), ubiquitin C-terminal hydrolase-L1 (UCH-L1), and αII-spectrin breakdown product (SBDP145), could also contribute to outcome prediction. The present study was initiated to assess whether the addition of biomarkers to the IMPACT prognostic calculator could improve its predictive power. Forty-five sTBI patients (GCS score≤8) from four different sites were investigated. We utilized the core model of the IMPACT calculator (age, GCS motor score, and reaction of pupils), and measured the level of GFAP, UCH-L1, and SBDP145 in serum and cerebrospinal fluid (CSF). The forecast and actual 6-month outcomes were compared by logistic regression analysis. The results of the core model itself, as well as serum values of GFAP and CSF levels of SBDP145, showed a significant correlation with the 6-month mortality using a univariate analysis. In the core model, the Nagelkerke R(2) value was 0.214. With multivariate analysis we were able to increase this predictive power with one additional biomarker (GFAP in CSF) to R(2)=0.476, while the application of three biomarker levels (GFAP in CSF, GFAP in serum, and SBDP145 in CSF) increased the Nagelkerke R(2) to 0.700. Our preliminary results underline the importance of biomarkers in outcome prediction, and encourage further investigation to expand the predictive power of contemporary outcome calculators and prognostic models in TBI.

A novel animal model of closed-head concussive-induced mild traumatic brain injury: development, implementation, and characterization

Closed-head concussive injury is one of the most common causes of traumatic brain injury (TBI). While single concussions result in short-term neurologic dysfunction, multiple concussions can result in cumulative damage and increased risk for neurodegenerative disease. Despite the prevalence of concussion, knowledge about what occurs in the brain following this injury is limited, in part due to the limited number of appropriate animal research models. To study clinically relevant concussion we recently developed a simple, non-invasive rodent model of closed-head projectile concussive impact (PCI) TBI. For this purpose, anesthetized rats were placed on a platform positioned above a torque-sealed microcentrifuge tube packed with fixed amounts of dry ice. Upon heating, rapid sublimation of the dry ice produced a build-up of compressed CO(2) that triggered an eruptive force causing the cap to launch as an intact projectile, resulting in a targeted PCI head injury. A stainless steel helmet was implemented to protect the head from bruising, yet allowing the brain to sustain a mild PCI event. Depending on the injury location and the application of the helmet, PCI-induced injuries ranged from severe (i.e., head injury with subdural hematomas, intracranial hemorrhage, and brain tissue damage), to mild (no head injury, intracranial hemorrhage, or gross morphological pathology). Although no gross pathology was evident in mild PCI-induced injury, the following protein changes and behavioral abnormalities were detected between 1 and 24 h after PCI injury: (1) upregulation of glial fibrillary acidic protein (GFAP) in hippocampal regions; (2) upregulation of ubiquitin carboxyl-terminal hydrolase L1 (UCHL-1) in cortical tissue; and (3) significant sensorimotor abnormalities. Overall, these results indicated that this PCI model was capable of replicating salient pathologies of a clinical concussion, and could generate reproducible and quantifiable outcome measures.

Elevated levels of serum glial fibrillary acidic protein breakdown products in mild and moderate traumatic brain injury are associated with intracranial lesions and neurosurgical intervention

STUDY OBJECTIVE

This study examines whether serum levels of glial fibrillary acidic protein breakdown products (GFAP-BDP) are elevated in patients with mild and moderate traumatic brain injury compared with controls and whether they are associated with traumatic intracranial lesions on computed tomography (CT) scan (positive CT result) and with having a neurosurgical intervention.

METHODS

This prospective cohort study enrolled adult patients presenting to 3 Level I trauma centers after blunt head trauma with loss of consciousness, amnesia, or disorientation and a Glasgow Coma Scale (GCS) score of 9 to 15. Control groups included normal uninjured controls and trauma controls presenting to the emergency department with orthopedic injuries or a motor vehicle crash without traumatic brain injury. Blood samples were obtained in all patients within 4 hours of injury and measured by enzyme-linked immunosorbent assay for GFAP-BDP (nanograms/milliliter).

RESULTS

Of the 307 patients enrolled, 108 were patients with traumatic brain injury (97 with GCS score 13 to 15 and 11 with GCS score 9 to 12) and 199 were controls (176 normal controls and 16 motor vehicle crash controls and 7 orthopedic controls). Receiver operating characteristic curves demonstrated that early GFAP-BDP levels were able to distinguish patients with traumatic brain injury from uninjured controls with an area under the curve of 0.90 (95% confidence interval [CI] 0.86 to 0.94) and differentiated traumatic brain injury with a GCS score of 15 with an area under the curve of 0.88 (95% CI 0.82 to 0.93). Thirty-two patients with traumatic brain injury (30%) had lesions on CT. The area under these curves for discriminating patients with CT lesions versus those without CT lesions was 0.79 (95% CI 0.69 to 0.89). Moreover, the receiver operating characteristic curve for distinguishing neurosurgical intervention from no neurosurgical intervention yielded an area under the curve of 0.87 (95% CI 0.77 to 0.96).

CONCLUSION

GFAP-BDP is detectable in serum within an hour of injury and is associated with measures of injury severity, including the GCS score, CT lesions, and neurosurgical intervention. Further study is required to validate these findings before clinical application.

[Which occupational groups in a hospital are particularly stressed?]

BACKGROUND AND OBJECTIVE

Increasing workload in health professionals and resulting health consequences have frequently been reported. We analysed the results from an employee attitude survey within a network of workplace health promotion and compared three occupational groups of a university hospital with two samples of employees of other industries.

METHOD

The survey was conducted in the years 2005, 2006 and 2007 using a standardized method, addressing 1748 employees of six companies. In order to compare specific occupational groups, both within the hospital and amongst different companies, five occupational groups were selected (medical profession, nursing service and administration of the hospital, academics of another company and employees of a financial service provider).

RESULTS

Some results were specific for an occupational group, such as lower back pain and skin diseases in nurses and exhaustion in clinicians. Regarding several items the responses of employees of the hospital's administration were similar to that of the medical professionals and differed significantly from the responses of administrative and related employees in other companies. Employees of all occupational groups of the hospital were often frustrated and felt their work was not appreciated. Frequent demands included improved work atmosphere, better appreciation of work and better information regarding innovations.

CONCLUSIONS

The analysis of standardized survey results specific for companies and occupational groups is an appropriate way to identify targets of health promotion. Constant over three surveys, again a high burden of stress was found in health care workers even affecting the administrative staff, regarding several work-related stress factors. According to our results activities to improve the working conditions in hospitals are urgently needed.

[Comparison of early retinal microvascular changes and microalbuminuria as indicators for increased cardioascular risk]

INTRODUCTION

Prevention of cardiovascular disease is an important goal in clinical medicine and public health. In the process, the diagnosis of early end-organ damage is a priority beside the treatment of classic cardiovascular risk factors. To achieve this, the ophthalmoscopic examination of the retinal vessels plays a prominent role. Alternatively, the quantification of low quantities of albumin in the urine (microalbuminuria) allows the detection of early vascular damage in the kidney. The question is addressed as to whether these two methods are interchangeable or are rather complementary.

PATIENTS AND METHODS

We examined 226 members of the staff of the University Hospital Erlangen who volunteered to participate in a preventive campaign. A comprehensive history was taken, and height, weight and blood pressure were measured. Analysis of serum lipids and determination of the urinary albumin/creatinine ratio were performed. Fotos of the central fundus were taken with a non-mydriatic camera and analysed by an experienced ophthalmologist in a standardised fashion. The risk for cardiovascular mortality within the next ten years was estimated from age, sex, blood pressure and serum cholesterol using the euroSCORE tables for Germany.

RESULTS

There was no signficant correlation between the arteriovenous ratio of the retinal vessels and the urinary albumin/creatinine ratio. Neither parameter correlated with the euroSCORE Germany. Arteriovenous crossings and focal narrowing of the retinal vessels were associated signficantly with an elevated euroSCORE risk.

CONCLUSIONS

In large population-based studies, the arteriovenous ratio and the urinary albumin/creatinine ratio have been confirmed as markers of cardiovascular risk. In our study, there was no correlation between these two parameters. Thus, they seem to present independent risk markers. The presence of arteriovenous crossings and focal narrowing seems to be linked more closely to the classic cardiovascular risk factors from which the euroSCORE is calculated. The ophathlmolscopic examination of retinal vessels and the analysis of urinary albumin/creatinine ratio seem to complement rather than replace each other.