Altered brain structural connectivity in patients with longstanding gut inflammation is correlated with psychological symptoms and disease duration

OBJECTIVE

We aimed to identify differences in network properties of white matter microstructure between asymptomatic ulcerative colitis (UC) participants who had a history of chronic gut inflammation, healthy controls (HCs) and a disease control group without gut inflammation (irritable bowel syndrome; IBS).

DESIGN

Diffusion weighted imaging was conducted in age and sex-matched participants with UC, IBS, and HCs (N = 74 each), together with measures of gastrointestinal and psychological symptom severity. Using streamline connectivity matrices and graph theory, we aimed to quantify group differences in brain network connectivity. Regions showing group connectivity differences were correlated with measures showing group behavioral and clinical differences.

RESULTS

UC participants exhibited greater centrality in regions of the somatosensory network and default mode network, but lower centrality in the posterior insula and globus pallidus compared to HCs (q < 0.05). Hub analyses revealed compromised hubness of the pallidus in UC and IBS compared to HCs which was replaced by increased hubness of the postcentral sulcus. Surprisingly, few differences in network matrices between UC and IBS were identified. In UC, centrality measures in the secondary somatosensory cortex were associated with depression (q < 0.03), symptom related anxiety (q < 0.04), trait anxiety (q < 0.03), and symptom duration (q < 0.05).

CONCLUSION

A history of UC is associated with neuroplastic changes in several brain networks, which are associated with symptoms of depression, trait and symptom-related anxiety, as well as symptom duration. When viewed together with the results from IBS subjects, these findings suggest that chronic gut inflammation as well as abdominal pain have a lasting impact on brain network organization, which may play a role in symptoms reported by UC patients, even when gut inflammation has subsided.

Anxiety symptoms are associated with smaller insular and orbitofrontal cortex volumes in late-life depression

BACKGROUND

Increasing understanding of the neural correlates of anxiety symptoms in late-life depression (LLD) could inform the development of more targeted and effective treatments.

METHODS

Grey matter volume (GMV) was assessed with volumetric magnetic resonance imaging in a sample of 113 adults ≥60 years with MDD using the following regions of interest: amygdala, anterior cingulate cortex (ACC), insula, orbitofrontal cortex (OFC), and temporal cortex.

RESULTS

After controlling for demographic (age, sex, education) and clinical variables (antidepressant use, anxiolytic use, duration of illness, medical comorbidity, cognitive functioning), greater severity of anxiety symptoms was associated with lower GMV bilaterally in the insula, F(1,102) = 6.63, p = 0.01, and OFC, F(1,102) = 8.35, p = 0.005. By contrast, depressive symptom severity was significantly associated with lower bilateral insula volumes, F(1,102) = 6.43, p = 0.01, but not OFC volumes, F(1,102) = 5.37, p = 0.02.

LIMITATIONS

Limitations include (1) the relatively mild nature of anxiety symptoms in our sample; (2) the cross-sectional research design, which prohibits inferences of directionality; (3) the relatively homogenous demographic of the sample, and (4) the exclusion of participants with significant psychiatric comorbidity, suicidality, or cognitive impairment.

CONCLUSIONS

Decreased OFC volumes may serve as a unique biomarker of anxiety symptoms in LLD. Future longitudinal and clinical studies with long-term follow up and more diverse samples will help further elucidate the biological, psychological, and social factors affecting associations between anxiety and brain morphology in LLD.

Piezoelectric 3-D Fibrous Poly(3-hydroxybutyrate)-Based Scaffolds Ultrasound-Mineralized with Calcium Carbonate for Bone Tissue Engineering: Inorganic Phase Formation, Osteoblast Cell Adhesion, and Proliferation

Elaboration of novel biocomposites providing simultaneously both biodegradability and stimulated bone tissue repair is essential for regenerative medicine. In particular, piezoelectric biocomposites are attractive because of a possibility to electrically stimulate cell response. In the present study, novel CaCO₃-mineralized piezoelectric biodegradable scaffolds based on two polymers, poly[( R)3-hydroxybutyrate] (PHB) and poly[3-hydroxybutyrate- co-3-hydroxyvalerate] (PHBV), are presented. Mineralization of the scaffold surface is carried out by the in situ synthesis of CaCO₃ in the vaterite and calcite polymorphs using ultrasound (U/S). Comparative characterization of PHB and PHBV scaffolds demonstrated an impact of the porosity and surface charge on the mineralization in a dynamic mechanical system, as no essential distinction was observed in wettability, structure, and surface chemical compositions. A significantly higher (4.3 times) piezoelectric charge and a higher porosity (∼15%) lead to a more homogenous CaCO₃ growth in 3-D fibrous structures and result in a two times higher relative mass increase for PHB scaffolds compared to that for PHBV. This also increases the local ion concentration incurred upon mineralization under U/S-generated dynamic mechanical conditions. The modification of the wettability for PHB and PHBV scaffolds from hydrophobic (nonmineralized fibers) to superhydrophilic (mineralized fibers) led to a pronounced apatite-forming behavior of scaffolds in a simulated body fluid. In turn, this results in the formation of a dense monolayer of well-distributed and proliferated osteoblast cells along the fibers. CaCO₃-mineralized PHBV surfaces had a higher osteoblast cell adhesion and proliferation assigned to a higher amount of CaCO₃ on the surface compared to that on PHB scaffolds, as incurred from micro-computed tomography (μCT). Importantly, a cell viability study confirmed biocompatibility of all the scaffolds. Thus, hybrid biocomposites based on the piezoelectric PHB polymers represent an effective scaffold platform functionalized by an inorganic phase and stimulating the growth of the bone tissue.

Neuroenhancement of High-Level Cognition: Evidence for Homeostatic Constraints of Non-invasive Brain Stimulation

Neuroenhancement aims to improve cognitive performance in typically and atypically functioning populations. However, it is currently debated whether it is also effective in exceptionally high-functioning individuals. Present theories suggest that homeostatic set points for learning and cortical plasticity limit the beneficial effects of neuroenhancement. To examine this possibility, we used transcranial random noise stimulation (tRNS) to non-invasively stimulate bilateral dorsolateral prefrontal cortices (DLPFC) of the world champion in mental calculation, G.M. TRNS did not change G.M.’s calculation performance compared to sham stimulation on an exceptionally complex arithmetic task. However, a sample of mathematicians who were not calculation prodigies (N = 6) showed reduced accuracy on a complex multiplication task in response to tRNS, relative to sham. Our findings suggest that there may be an upper limit for cognitive enhancement and that further attempts to enhance performance using tRNS (at least with the current parameters) may impair optimal functioning. The discussion of potential negative effects of brain stimulation for cognitive enhancement is critical, as it may lead to unintended impairments in different subgroups of the population.

Psychobiological factors of resilience and depression in late life

In contrast to traditional perspectives of resilience as a stable, trait-like characteristic, resilience is now recognized as a multidimentional, dynamic capacity influenced by life-long interactions between internal and environmental resources. We review psychosocial and neurobiological factors associated with resilience to late-life depression (LLD). Recent research has identified both psychosocial characteristics associated with elevated LLD risk (e.g., insecure attachment, neuroticism) and psychosocial processes that may be useful intervention targets (e.g., self-efficacy, sense of purpose, coping behaviors, social support). Psychobiological factors include a variety of endocrine, genetic, inflammatory, metabolic, neural, and cardiovascular processes that bidirectionally interact to affect risk for LLD onset and course of illness. Several resilience-enhancing intervention modalities show promise for the prevention and treatment of LLD, including cognitive/psychological or mind-body (positive psychology; psychotherapy; heart rate variability biofeedback; meditation), movement-based (aerobic exercise; yoga; tai chi), and biological approaches (pharmacotherapy, electroconvulsive therapy). Additional research is needed to further elucidate psychosocial and biological factors that affect risk and course of LLD. In addition, research to identify psychobiological factors predicting differential treatment response to various interventions will be essential to the development of more individualized and effective approaches to the prevention and treatment of LLD.

Neurocognitive Correlates of Resilience in Late-Life Depression

OBJECTIVE

Increasing understanding of the neurocognitive correlates of resilience in late-life depression (LLD) could inform interventions to promote more sustained remission. We investigated cross-sectional relations between baseline resilience and domains of neurocognitive functioning in depressed older adults enrolled in one of four trials.

METHODS

Participants (N = 288) completed neurocognitive tests of memory, language performance, and executive functioning as well as measures of subjective memory performance and components of resilience (grit, active coping self-efficacy, accommodative coping self-efficacy, and spirituality).

RESULTS

Medium-sized associations were observed between greater resilience (overall resilience, accommodative coping) and lower frequency of self-reported forgetting. Small positive associations were observed between language performance and total resilience, active coping self-efficacy, and accommodative coping self-efficacy. Small negative associations were observed between spirituality and each objective measure of cognitive performance.

CONCLUSION

Future longitudinal studies will help elucidate the complex relation between resilience and cognitive functioning in LLD. In addition, randomized controlled trials targeting coping self-efficacy may inform the development of more effective and personalized interventions.

Resilience and amygdala function in older healthy and depressed adults

BACKGROUND

Previous studies suggest that low emotional resilience may correspond with increased or over-active amygdala function. Complementary studies suggest that emotional resilience increases with age; older adults tend to have decreased attentional bias to negative stimuli compared to younger adults. Amygdala nuclei and related brain circuits have been linked to negative affect, and depressed patients have been demonstrated to have abnormal amygdala function.

METHODS

In the current study, we correlated psychological resilience measures with amygdala function measured with resting-state arterial spin-labelled (ASL) and blood-oxygenation-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) in older adults with and without depression. Specifically, we targeted the basolateral, centromedial, and superficial nuclei groups of the amygdala, which have different functions and brain connections.

RESULTS

High levels of psychological resilience correlated with lower basal levels of amygdala activity measured with ASL fMRI. High resilience also correlated with decreased connectivity between amygdala nuclei and the ventral default-mode network independent of depression status. Instead, lower depression symptoms were associated with higher connectivity between the amygdalae and dorsal frontal networks.

LIMITATIONS

Future multi-site studies with larger sample size and improved neuroimaging technologies are needed. Longitudinal studies that target resilience to naturalistic stressors will also be a powerful contribution to the field.

CONCLUSIONS

Our results suggest that resilience in older adults is more closely related to function in ventral amygdala networks, while late-life depression is related to reduced connectivity between the amygdala and dorsal frontal regions.

Resilience and White Matter Integrity in Geriatric Depression

OBJECTIVE

Greater psychological resilience may protect against developing depression in a growing geriatric population. Identifying the neural correlates of resilience in geriatric depression could provide neurobiologic targets to inform clinical interventions. However, most prior neuroimaging studies have only considered the presence or absence of resilience and have not addressed the multifactorial nature of resilience. The current study aimed to establish the neural correlates of four factors of resilience in the depressed elderly.

METHODS

White matter integrity was assessed using diffusion-weighted magnetic resonance imaging data collected from 70 older adults with major depressive disorder. We used four resilience factors previously derived in an exploratory factor analysis of the Connor-Davidson Resilience Scale in a large sample of depressed older adults: 1, grit; 2, active coping self-efficacy; 3, accommodative coping self-efficacy; and 4, spirituality.

RESULTS

The resilience factor "grit" was positively associated with fractional anisotropy in the callosal region connecting prefrontal cortex and fractional anisotropy in cingulum fibers; however, the latter did not survive correction for multiple comparisons.

CONCLUSION

Structural integrity of major white matter pathways implicated in cognitive control and emotion regulation (i.e., connecting prefrontal cortex) was positively associated with the resilience factor "grit" in our sample of older adults with depression. Prospective studies are needed to determine the utility of the structural integrity of these pathways as a biomarker in predicting risk for depression and treatment response.

The Effect of Three Different Miniaturized Blood Purification Devices on Plasma Cytokine Concentration in an Ex Vivo Model of Endotoxinemia

Purpose

A novel type of adsorptive plasma filtering device (ETX-A) capable of removing endotoxin from blood in a single step has recently been developed using nanotechnology.

Methods

In a miniaturized, ex vivo model of extracorporeal circuits, we tested the capacity to reduce plasma cytokine concentration of ETX-A filters in comparison to standard high-flux (HF) filters, high cut-off (HCO) filters and a control. Blood from six healthy volunteers was spiked with endotoxin and then circulated through closed (ETX-A, control) or open (HF, HCO) circuits. Blood flow was set at 16 ml/min and filtration flow at 1 ml/min. Samples for measurement of IL-1ra and IL-6 were taken at baseline and at 4 hours.

Results

Compared to control (703.3 [850.6] pg/mL), in HCO (383.5 [1144.1] pg/mL) and ETX-A (490.1 [683.2] pg/mL) filters, plasma IL-1ra pooled pre- and postfilter concentrations were lower at the end of the experiment (P=0.002; P=0.050, respectively) whereas, in standard HF filters, IL-1ra concentration was higher than control. HCO showed a trend toward a reduced relative increase in IL-6 concentration from commencement to end of experiment compared to control (P=0.07). After pooling end-of-experiment plasma cytokine values of novel blood purification devices, we found HCO + ETX-A superior to H with regard to reduction of IL-1ra (-27.0 [−20.5]% vs. 8.1 [18.9]%; P<01) and IL-6 (-18.0 [38.3]% vs. −1.1 [24.3]%; P=0.050) compared to control.

Conclusions

HCO and ETX-A appeared to significantly reduce plasma IL-1ra and, when combined, plasma IL-6 concentration as well. It appears desirable to manufacture full-size blood purification devices using this technology and to explore their effect on cytokine removal.

Characterization of aluminum, aluminum oxide and titanium dioxide nanomaterials using a combination of methods for particle surface and size analysis

The application of appropriate analytical techniques is essential for nanomaterial (NM) characterization. In this study, we compared different analytical techniques for NM analysis. Regarding possible adverse health effects, ionic and particulate NM effects have to be taken into account. As NMs behave quite differently in physiological media, special attention was paid to techniques which are able to determine the biosolubility and complexation behavior of NMs. Representative NMs of similar size were selected: aluminum (Al⁰) and aluminum oxide (Al₂O₃), to compare the behavior of metal and metal oxides. In addition, titanium dioxide (TiO₂) was investigated. Characterization techniques such as dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) were evaluated with respect to their suitability for fast characterization of nanoparticle dispersions regarding a particle's hydrodynamic diameter and size distribution. By application of inductively coupled plasma mass spectrometry in the single particle mode (SP-ICP-MS), individual nanoparticles were quantified and characterized regarding their size. SP-ICP-MS measurements were correlated with the information gained using other characterization techniques, i.e. transmission electron microscopy (TEM) and small angle X-ray scattering (SAXS). The particle surface as an important descriptor of NMs was analyzed by X-ray diffraction (XRD). NM impurities and their co-localization with biomolecules were determined by ion beam microscopy (IBM) and confocal Raman microscopy (CRM). We conclude advantages and disadvantages of the different techniques applied and suggest options for their complementation. Thus, this paper may serve as a practical guide to particle characterization techniques.

The application of appropriate analytical techniques is essential for nanomaterial (NM) characterization.

Transcranial random noise stimulation mitigates increased difficulty in an arithmetic learning task

Proficiency in arithmetic learning can be achieved by using a multitude of strategies, the most salient of which are procedural learning (applying a certain set of computations) and rote learning (direct retrieval from long-term memory). Here we investigated the effect of transcranial random noise stimulation (tRNS), a non-invasive brain stimulation method previously shown to enhance cognitive training, on both types of learning in a 5-day sham-controlled training study, under two conditions of task difficulty, defined in terms of item repetition. On the basis of previous research implicating the prefrontal and posterior parietal cortex in early and late stages of arithmetic learning, respectively, sham-controlled tRNS was applied to bilateral prefrontal cortex for the first 3 days and to the posterior parietal cortex for the last 2 days of a 5-day training phase. The training involved learning to solve arithmetic problems by applying a calculation algorithm; both trained and untrained problems were used in a brief testing phase at the end of the training phase. Task difficulty was manipulated between subjects by using either a large ("easy" condition) or a small ("difficult" condition) number of repetition of problems during training. Measures of attention and working memory were acquired before and after the training phase. As compared to sham, participants in the tRNS condition displayed faster reaction times and increased learning rate during the training phase; as well as faster reaction times for both trained and untrained (new) problems, which indicated a transfer effect after the end of training. All stimulation effects reached significance only in the "difficult" condition when number of repetition was lower. There were no transfer effects of tRNS on attention or working memory. The results support the view that tRNS can produce specific facilitative effects on numerical cognition--specifically, on arithmetic learning. They also highlight the importance of task difficulty in the neuromodulation of learning, which in the current study due to the manipulation of item repetition might have being mediated by the memory system.

Linking GABA and glutamate levels to cognitive skill acquisition during development

Developmental adjustments in the balance of excitation and inhibition are thought to constrain the plasticity of sensory areas of the cortex. It is unknown however, how changes in excitatory or inhibitory neurochemical expression (glutamate, γ-aminobutyric acid (GABA)) contribute to skill acquisition during development. Here we used single-voxel proton magnetic resonance spectroscopy (1H-MRS) to reveal how differences in cortical glutamate vs. GABA ratios relate to face proficiency and working memory abilities in children and adults. We show that higher glutamate levels in the inferior frontal gyrus correlated positively with face processing proficiency in the children, but not the adults, an effect which was independent of age-dependent differences in underlying cortical gray matter. Moreover, we found that glutamate/GABA levels and gray matter volume are dissociated at the different maturational stages. These findings suggest that increased excitation during development is linked to neuroplasticity and the acquisition of new cognitive skills. They also offer a new, neurochemical approach to investigating the relationship between cognitive performance and brain development across the lifespan.

A familiar font drives early emotional effects in word recognition

The emotional connotation of a word is known to shift the process of word recognition. Using the electroencephalographic event-related potentials (ERPs) approach it has been documented that early attentional processing of high-arousing negative words is shifted at a stage of processing where a presented word cannot have been fully identified. Contextual learning has been discussed to contribute to these effects. The present study shows that a manipulation of the familiarity with a word's shape interferes with these earliest emotional ERP effects. Presenting high-arousing negative and neutral words in a familiar or an unfamiliar font results in very early emotion differences only in case of familiar shapes, whereas later processing stages reveal similar emotional effects in both font conditions. Because these early emotion-related differences predict later behavioral differences, it is suggested that contextual learning of emotional valence comprises more visual features than previously expected to guide early visual-sensory processing.

Not all brains are created equal: the relevance of individual differences in responsiveness to transcranial electrical stimulation

A current issue in the research of augmentation of brain functions using transcranial electrical stimulation (tES) is the diversity and inconsistency in outcome results. Similar studies often report different results, depending on the parameters and tasks used. Such inconsistencies have led to significant doubts about the efficacy of the method in the broader scientific community, despite its promising potential for patient recovery and treatment. Evidence on the large variability in individual cortical excitability and response to tES suggests that stimulation may affect individuals differently, depending on the subject’s age, gender, brain state, hormonal levels, and pre-existing regional excitability. Certain factors might even lead to the reversal of polarity-dependent effects, and therefore have crucial implications for neurorehabilitation and cognitive enhancement. Research paradigms may have to be refined in the future to avoid the confounding effects of such factors.

The effect of transcranial direct current stimulation: a role for cortical excitation/inhibition balance?

Transcranial direct current stimulation (tDCS) is a promising tool for cognitive enhancement and neurorehabilitation in clinical disorders in both cognitive and clinical domains (e.g., chronic pain, tinnitus). Here we suggest the potential role of tDCS in modulating cortical excitation/inhibition (E/I) balance and thereby inducing improvements. We suggest that part of the mechanism of action of tDCS can be explained by non-invasive modulations of the E/I balance.

Conceptual basis for prescriptive growth standards from conception to early childhood: present and future

BACKGROUND

Healthy growth in utero and after birth is fundamental for lifelong health and wellbeing. The World Health Organization (WHO) recently published standards for healthy growth from birth to 6 years of age; analogous standards for healthy fetal growth are not currently available. Current fetal growth charts in use are not true standards, since they are based on cross-sectional measurements of attained size under conditions that do not accurately reflect normal growth. In most cases, the pregnant populations and environments studied are far from ideal; thus the data are unlikely to reflect optimal fetal growth. A true standard should reflect how fetuses and newborns 'should' grow under ideal environmental conditions.

OBJECTIVE

The development of prescriptive intrauterine and newborn growth standards derived from the INTERGROWTH-21(st) Project provides the data that will allow us for the first time to establish what is 'normal' fetal growth.

METHODS

The INTERGROWTH-21(st) study centres provide the data set obtained under pre-established standardised criteria, and details of the methods used are also published.

DESIGN

Multicentre study with sites in all major geographical regions of the world using a standard evaluation protocol.

RESULTS

These standards will assess risk of abnormal size at birth and serve to evaluate potentially effective interventions to promote optimal growth beyond securing survival.

DISCUSSION

The new normative standards have the potential to impact perinatal and neonatal survival and beyond, particularly in developing countries where fetal growth restriction is most prevalent. They will help us identify intrauterine growth restriction at earlier stages of development, when preventive or corrective strategies might be more effective than at present.

CONCLUSION

These growth standards will take us one step closer to effective action in preventing and potentially reversing abnormal intrauterine growth. Achieving 'optimal' fetal growth requires that we act not only during pregnancy but that we optimize the maternal uterine environment from the time before conception, through embryonic development until fetal growth is complete. The remaining challenge is how 'early' will we be able to act, now that we can better monitor fetal growth.

Can transcranial electrical stimulation improve learning difficulties in atypical brain development? A future possibility for cognitive training

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Transcranial electrical stimulation (TES) can improve cognitive training effects in adults.

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TES can enhance neuroplasticity from the molecular level to the system level.

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We discuss the usage of TES with cognitive training in atypically developing children.

•

We discuss the possible cognitive and physical side effects of TES.

Learning difficulties in atypical brain development represent serious obstacles to an individual's future achievements and can have broad societal consequences. Cognitive training can improve learning impairments only to a certain degree. Recent evidence from normal and clinical adult populations suggests that transcranial electrical stimulation (TES), a portable, painless, inexpensive, and relatively safe neuroenhancement tool, applied in conjunction with cognitive training can enhance cognitive intervention outcomes. This includes, for instance, numerical processing, language skills and response inhibition deficits commonly associated with profound learning difficulties and attention-deficit hyperactivity disorder (ADHD). The current review introduces the functional principles, current applications and promising results, and potential pitfalls of TES. Unfortunately, research in child populations is limited at present. We suggest that TES has considerable promise as a tool for increasing neuroplasticity in atypically developing children and may be an effective adjunct to cognitive training in clinical settings if it proves safe. The efficacy and both short- and long-term effects of TES on the developing brain need to be critically assessed before it can be recommended for clinical settings.

[S3 guideline - diagnosis and treatment of gastric carcinoma: relevance for radiologic imaging]

The new German S3 guideline regarding stomach cancer includes a variety of innovations with respect to the diagnosis and treatment of adenocarcinoma of the stomach and the esophagogastric junction. The guideline has been strongly supported by the "oncology" guidelines program consisting of the "Deutsche Krebshilfe" and the German Cancer Society and the AWMF (Dr. M. Follmann). This guideline contains evidence-based treatment recommendations and quality indicators for guideline implementation and evaluation in order to improve broad medical care and to facilitate development and subsequent adjustment. The purpose of this article is to introduce the innovations with regard to radiological diagnosis and to discuss the latest literature on the subject.

Interpolation of Illusory Pain in the Human Somatosensory System

Three coins are lined up with the middle coin at room temperature and flanking coins cooled down to 4° C. If digits 2 and 4 are placed on the outer coins and digit 3 on the middle coin, the latter also feels cold; a striking example of perceptual filling in of temperature. We show that if digits 2 and 4 are placed on a thermal grill with alternating hot and cold bars, while digit 3 is placed on cardboard, the sensation of pain will also spread to the middle finger.

The phantom head

A student volunteer was asked to stand just behind a mannequin so that the student was looking at the back of the mannequin's plastic head. The experimenter stood off to one side and used her two hands to stroke and tap the back of the student's head in perfect synchrony with the back of the mannequin's head. After 1-2 min the majority of naive subjects tested began experiencing the sensations as emerging from the mannequin's head rather than from their own, demonstrating a novel 'phantom-head' illusion. The fact that sensory referral here occurs to a part of the body that is not normally visually accessible challenges the leading Hebbian explanation of the well-studied rubber-hand illusion.

Comparative studies on the retardation and reduction of glyphosate during subsurface passage

The herbicide Glyphosate was detected in River Havel (Berlin, Germany) in concentrations between 0.1 and 2 μg/L (single maximum outlier: 5 μg/L). As the river indirectly acts as drinking water source for the city's 3.4 Mio inhabitants potential risks for drinking water production needed to be assessed. For this reason laboratory (sorption and degradation studies) and technical scale investigations (bank filtration and slow sand filter experiments) were carried out. Batch adsorption experiments with Glyphosate yielded a low K(F) of 1.89 (1/n = 0.48) for concentrations between 0.1 and 100 mg/L. Degradation experiments at 8 °C with oxygen limitation resulted in a decrease of Glyphosate concentrations in the liquid phase probably due to slow adsorption (half life: 30 days). During technical scale slow sand filter (SSF) experiments Glyphosate attenuation was 70-80% for constant inlet concentrations of 0.7, 3.5 and 11.6 μg/L, respectively. Relevant retardation of Glyphosate breakthrough was observed despite the low adsorption potential of the sandy filter substrate and the relatively high flow velocity. The VisualCXTFit model was applied with data from typical Berlin bank filtration sites to extrapolate the results to a realistic field setting and yielded sufficient attenuation within a few days of travel time. Experiments on an SSF planted with Phragmites australis and an unplanted SSF with mainly vertical flow conditions to which Glyphosate was continuously dosed showed that in the planted SSF Glyphosate retardation exceeds 54% compared to 14% retardation in the unplanted SSF. The results show that saturated subsurface passage has the potential to efficiently attenuate glyphosate, favorably with aerobic conditions, long travel times and the presence of planted riparian boundary buffer strips.

PET-guided treatment in locally advanced adenocarcinoma of the esophagogastric junction (AEG): The MUNICON-II study

3

Background: Previous studies demonstrated that fluorodeoxyglucose (FDG)-PET can help to detect response early during neoadjuvant chemotherapy. The prognosis of metabolic non-responders is poor. Therefore, we initiated the prospective MUNICON-II study to determine the value of salvage neoadjuvant chemoradiation in early PET nonresponders.

Methods: 56 patients (pts) with locally advanced AEG type I and II (cT3/4 Nx M0) were included. Tumor glucose uptake was assessed by FDG-PET before and 14 days after initiation of chemotherapy. PET nonresponse was defined as a decrease of the tumor FDG standard uptake value < 35%. Nonresponders received salvage preoperative chemoradiation consisting of external beam radiation 32 Gy (1.6 Gy/fr x 2/day) plus daily cisplatin 6mg/m2 and then proceeded to surgery. Metabolic responders continued with chemotherapy (platin/5-FU-based) for 3 months.

Results: 33 pts had a PET response, 23 had a PET nonresponse. Resection was performed on 54 pts. R0 was achieved in 27 (82%) PET responders versus 16 (70%) nonresponders (p = 0.51). Major histologic remissions (< 10% residual tumor) were observed in 12 PET responders (36%) and 6 PET non responders (26%). After a median follow-up time of 38.0 mon, the median event-free survival (EFS) and the median overall survival (OS) were not yet reached in the PET responders, while EFS was 15.4 mon and OS was 18.3 mon in nonresponders.

Conclusions: This study confirms the prognostic value of early metabolic response evaluation during neoadjuvant chemotherapy. Histopathologic responses were observed after salvage chemoradiation, but the clinical outcome of early PET non-responders to chemotherapy remains poor, indicating a dismal tumor biology in this group of pts.

No significant financial relationships to disclose.

Sustained renal response to mycophenolate mofetil and CNI taper promotes survival in liver transplant patients with CNI-related renal dysfunction

AIM

The aim of this trial was to evaluate the impact of conversion from a calcineurin-inhibitor (CNI)-based immunosuppressive regimen to mycophenolate mofetil (MMF) and reduced-dose CNI on long-term renal function and survival in a series of 63 liver transplant patients with CNI-induced renal dysfunction.

METHODS

CNI dosage was significantly tapered after introduction of 2,000 mg MMF per day. Renal function was assessed by determination of serum creatinine levels and calculated creatinine clearance (CCl). The impact of relevant clinical parameters on renal function and survival post-conversion was analyzed by univariate and multivariate analysis.

RESULTS

At 60 months post-conversion, mean creatinine level had significantly declined from 197.2±58.3 μmol/l at baseline to 160.0±76.5 μmol/l, and mean CCl has significantly increased from 38.4±13.4 ml/min at baseline to 47.9±21.1 ml/min (p<0.001), respectively. Forty-six patients (73.1%) demonstrated sustained renal response to modified immunosuppression. Full-dose MMF medication (p=0.006) and the early conversion (p=0.02) were identified as independent predictors of persistent renal function improvement. Sustained renal response to MMF plus reduced-dose CNI was identified as the most relevant independent promoter of long-term survival (hazard ratio 6.9). Five-year survival rate post-conversion was 93.9% in renal responders and 64.3% in renal non-responders (log rank<0.001).

CONCLUSIONS

Sustained renal response to MMF and CNI dose reduction promotes long-term survival in liver transplant patients with CNI-induced renal dysfunction.

Naloxone stimulation test in women with hypothalamic amenorrhea: a preliminary report

We researched the possibility of the induction of ovulation by means of chronic opioid receptor blockade in 4 women with hypothalamic amenorrhea. Daily 4 mg naloxone were given as a bolus injection intravenously. By means of continuous determination of LH, FSH, 17-beta-estradiol (E2) and progesterone as well as of sonographic folliculometry follicular growth and subsequent ovulation should have been proved. Neither we found alterations of the basal values of LH, FSH, E2 and progesterone, nor we observed a follicular growth. These results lead us to the conclusion to put a naloxone stimulation test before further therapy. In this way opioid mediated hypothalamic ovarian insufficiencies can be registered and a therapy optimum can be reached early.

Reduced l-arginine transport and nitric oxide synthesis in human umbilical vein endothelial cells from intrauterine growth restriction pregnancies is not further altered by hypoxia

Intrauterine growth restriction (IUGR) is associated with chronic fetal hypoxia, altered placental vasodilatation and reduced endothelial nitric oxide synthase (eNOS) activity. In human umbilical vein endothelial cells (HUVEC) from pregnancies complicated with IUGR (IUGR cells) and in HUVEC from normal pregnancies (normal cells) cultured under hypoxia l-arginine transport is reduced; however, the mechanisms leading to this dysfunction are unknown. We studied hypoxia effect on l-arginine transport and human cationic amino acid transporters 1 (hCAT-1) expression, and the potential NO and protein kinase C alpha (PKCalpha) involvement. Normal or IUGR HUVEC monolayers were exposed (0-24h) to 5% O(2) (normoxia), and 1 or 2% O(2) (hypoxia). l-Arginine transport and hCAT-1 expression, phosphorylated and total PKCalpha or eNOS protein and mRNA expression were quantified. eNOS involvement was tested using a siRNA against eNOS (eNOS-siRNA) adenovirus. IUGR cells in normoxia or hypoxia, and normal cells in hypoxia exhibited reduced l-arginine transport, hCAT-1 expression, NO synthesis and eNOS phosphorylation at Serine(1177), effects reversed by calphostin C (PKC inhibitor) and S-nitroso-N-acetyl-l,d-penicillamine (SNAP, NO donor). However, N(G)-nitro-l-arginine methyl ester (l-NAME, NOS inhibitor) reduced hCAT-1 expression only in normal cells in normoxia. Increased Thr(638)-phosphorylated PKCalpha was exhibited by IUGR cells in normoxia or hypoxia and normal cells in hypoxia. The effects of hypoxia in normal cells were mimicked in eNOS-siRNA transduced cells; however, IUGR phenotype was unaltered by eNOS knockdown. Thus, IUGR- and hypoxia-reduced l-arginine transport could result from increased PKCalpha, but reduced eNOS activity leading to a lower hCAT-1 expression in HUVEC. In addition, IUGR endothelial cells are either not responsive or maximally affected by hypoxia. These mechanisms could be responsible for placental dysfunction in diseases where fetal endothelium is chronically exposed to hypoxia, such as IUGR.

Das Revisionsverfahren der medizinischen Klassifikationen in Deutschland

In this publication the process for the revision of ICD-10-GM and OPS are elucidated. Therefore the form for proposals is explained, the "aspects of revision of the OPS" are described as well as the steps of processing and consultations within the revision of the classifications. Finally the different formats of the published files are described.

Ultrasound and mammography guided wire marking of non-palpable breast lesions: analysis of 741 cases

PURPOSE

Aim of the study were to evaluate the success of ultrasound and mammography guided wire marking of non-palpable breast lesions and the results of specimen mammography/ultrasonography, completeness of resection, and number of secondary resections (during the initial surgical session and as a separate intervention) were analysed.

MATERIALS AND METHODS

Between May 1994 and December 2004, 668 women with 741 non-palpable breast lesions underwent surgery at the Greifswald University Department of Gynaecology and Obstetrics. Ultrasound directed wire marking was used in 418, mammography directed marking in 284 cases. In 39 lesions, both techniques were combined.

RESULTS

Out of all lesions approached with ultrasound directed wire marking, 88 (21.1 %) were malignant. Among lesions marked during mammography, 52 (19.3 %) were malignant. Specimen ultrasonography indicated that 90.9 % of lesions were resected completely. Specimen mammography demonstrated complete resection in 89.1 %. On histological examination, 19.5 % of the malignant lesions marked with sonographic guiding and 36.5 % of the malignant lesions marked with mammographic guiding did not have clear margins. Secondary resections (during the first procedure) for incomplete specimens were needed in 10 patients in whom sonographic localisation had been used, and in 25 patients in whom mammographic localisation had been employed. A second surgical session for secondary resection was required in 5.5 % of lesions marked with ultrasound and in 12.3 % of lesions marked with mammography guidance.

CONCLUSION

Sonography directed wire localisation appears to be superior to the respective mammographic method. Ultrasound guided wire marking should be considered the preferred method for all mammographic lesions with an ultrasonographic equivalent and no micro-calcifications.

Guided self-assembly of lateral InAs/GaAs quantum-dot molecules for single molecule spectroscopy

We report on the growth and characterization of lateral InAs/GaAs (001) quantum-dot molecules (QDMs) suitable for single QDM optical spectroscopy. The QDMs, forming by depositing InAs on GaAs surfaces with self-assembled nanoholes, are aligned along the [] direction. The relative number of isolated single quantum dots (QDs) is substantially reduced by performing the growth on GaAs surfaces containing stepped mounds. Surface morphology and X-ray measurements suggest that the strain produced by InGaAs-filled nanoholes superimposed to the strain relaxation at the step edges are responsible for the improved QDM properties. QDMs are Ga-richer compared to single QDs, consistent with strain- enhanced intermixing. The high optical quality of single QDMs is probed by micro-photoluminescence spectroscopy in samples with QDM densities lower than 10⁸ cm⁻².

Local structure of a rolled-up single crystal: an X-ray microdiffraction study of individual semiconductor nanotubes

Crystals with cylindrical symmetry, not existing in nature, are mimicked by the roll-up of single-crystalline and highly strained semiconductor bilayers. Exploiting this, the local structure of such individual rolled-up nanotubes is locally probed and quantified nondestructively by x-ray microbeam diffraction. A comparison to simulations, based on the minimization of the elastic energy, allows us to determine layer thicknesses and lattice parameter distributions within the strongly curved bilayers.

[Communication center in public health]

The Communications Center's portfolio covers areas such as marketing, contacts, distribution of information, sales activities and collection of bills by telephone (encashment). A special emphasis is Customer Care Management (Customer Relationship Management) to the patient and his caregivers (relatives), the customers, especially the physicians who send their patients to the hospital and the hospital doctor. By providing communication centers, the hospital would be able to improve the communication with the G.P.s, and identify the wishes and requirements more accurately and easily from the beginning. Dealing effectively with information and communication is already also of special importance for hospital doctors today. One can assume that the demands on doctors in this respect will become even more complex in the future. Doctors who are involved in scientific research are of course fully aware of the growing importance of the Internet with its new information and communication channels. Therefore analysing the current situation, the demands on a future information management system can be formulated: A system that will help doctors to avoid dealing with little goal-oriented information and thus setting up effective communication channels; an information system which is multi-media oriented towards the interests and needs of the patients and patient's relatives and which is further developed continually and directly by those involved.