Individualized and clinically derived stimuli activate limbic structures in depression: an fMRI study

Objectives

In the search for neurobiological correlates of depression, a major finding is hyperactivity in limbic-paralimbic regions. However, results so far have been inconsistent, and the stimuli used are often unspecific to depression. This study explored hemodynamic responses of the brain in patients with depression while processing individualized and clinically derived stimuli.

Methods

Eighteen unmedicated patients with recurrent major depressive disorder and 17 never-depressed control subjects took part in standardized clinical interviews from which individualized formulations of core interpersonal dysfunction were derived. In the patient group such formulations reflected core themes relating to the onset and maintenance of depression. In controls, formulations reflected a major source of distress. This material was thereafter presented to subjects during functional magnetic resonance imaging (fMRI) assessment.

Results

Increased hemodynamic responses in the anterior cingulate cortex, medial frontal gyrus, fusiform gyrus and occipital lobe were observed in both patients and controls when viewing individualized stimuli. Relative to control subjects, patients with depression showed increased hemodynamic responses in limbic-paralimbic and subcortical regions (e.g. amygdala and basal ganglia) but no signal decrease in prefrontal regions.

Conclusions

This study provides the first evidence that individualized stimuli derived from standardized clinical interviewing can lead to hemodynamic responses in regions associated with self-referential and emotional processing in both groups and limbic-paralimbic and subcortical structures in individuals with depression. Although the regions with increased responses in patients have been previously reported, this study enhances the ecological value of fMRI findings by applying stimuli that are of personal relevance to each individual's depression.

The role of mentalization in the psychoanalytic treatment of chronic depression

Mentalization has been proposed as a key concept in understanding therapeutic change in patients with Borderline Personality Disorder (BPD). However, little is known about mentalization in chronic depression. This study investigated the role of mentalization in the long-term psychoanalytic treatment of chronic depression. Mentalization measured with the Reflective Functioning Scale (RFS) was examined in patients with chronic depression (n = 20) in long-term psychoanalytic treatment and compared to healthy controls (n = 20). Results show that global RF scores did not differ significantly between patients and controls. However, depressed patients tended to have lower RF scores concerning issues of loss. Furthermore, RF was unrelated to symptoms and distress as assessed by the Beck Depression Inventory (BDI) and the SCL-90. RF did not predict therapeutic outcome as measured with the BDI but predicted changes in general distress after 8 months of psychoanalytic treatment as measured by the SCL-90. Moreover, correlations between RF and the Helping Alliance Questionnaire indicated that patients with higher RF were able to establish a therapeutic alliance more easily compared to patients with low RF.

Natural memory beyond the storage model: repression, trauma, and the construction of a personal past

Naturally occurring memory processes show features which are difficult to investigate by conventional cognitive neuroscience paradigms. Distortions of memory for problematic contents are described both by psychoanalysis (internal conflicts) and research on post-traumatic stress disorder (PTSD; external traumata). Typically, declarative memory for these contents is impaired - possibly due to repression in the case of internal conflicts or due to dissociation in the case of external traumata - but they continue to exert an unconscious pathological influence: neurotic symptoms or psychosomatic disorders after repression or flashbacks and intrusions in PTSD after dissociation. Several experimental paradigms aim at investigating repression in healthy control subjects. We argue that these paradigms do not adequately operationalize the clinical process of repression, because they rely on an intentional inhibition of random stimuli (suppression). Furthermore, these paradigms ignore that memory distortions due to repression or dissociation are most accurately characterized by a lack of self-referential processing, resulting in an impaired integration of these contents into the self. This aspect of repression and dissociation cannot be captured by the concept of memory as a storage device which is usually employed in the cognitive neurosciences. It can only be assessed within the framework of a constructivist memory concept, according to which successful memory involves a reconstruction of experiences such that they fit into a representation of the self. We suggest several experimental paradigms that allow for the investigation of the neural correlates of repressed memories and trauma-induced memory distortions based on a constructivist memory concept.

Expression intensity, gender and facial emotion recognition: Women recognize only subtle facial emotions better than men

Two experiments were conducted in order to investigate the effect of expression intensity on gender differences in the recognition of facial emotions. The first experiment compared recognition accuracy between female and male participants when emotional faces were shown with full-blown (100% emotional content) or subtle expressiveness (50%). In a second experiment more finely grained analyses were applied in order to measure recognition accuracy as a function of expression intensity (40%-100%). The results show that although women were more accurate than men in recognizing subtle facial displays of emotion, there was no difference between male and female participants when recognizing highly expressive stimuli.

Habitual emotion regulation strategies and depressive symptoms in healthy subjects predict fMRI brain activation patterns related to major depression

The response-focused emotion regulation style 'Expressive suppression' has been associated with symptoms of lower psychological well-being and increased function magnetic resonance imaging (fMRI) activation of the sublenticular extended amygdala (SLEA) in patients with major depression. Extending prior studies on active emotion regulation, we were interested in effects of habitual emotion regulation on neurobiology. Thirty subjects with either relatively high or low suppression scores as assessed with the Emotion Regulation Questionnaire without symptoms of clinical depression participated in the study. They were instructed to expect and then perceive emotionally unpleasant, pleasant or neutral stimuli selected from the International Affective Picture System that were announced by a congruent cue during fMRI. In the subjects with high suppression scores, decreased activation of the orbital medial prefrontal cortex (oMFC) when expecting negative pictures and increased activation of the SLEA upon presentation of neutral stimuli were found. Subclinical depression ratings independently of suppression scores in the healthy subjects were positively correlated with brain activation in the SLEA when expecting negative pictures. SLEA hyperactivity may represent an emotional responsivity that involves less successful habitual emotion regulation and a tendency to depressed mood in healthy subjects, as shown in patients with major depression. Decreased anticipatory oMFC activation may parallel a lack of antecedent emotion regulation in subjects with high suppression scores, representing another neurobiological predictor of lower mental well-being.

Cell adhesion strength is controlled by intermolecular spacing of adhesion receptors

Spatial patterning of biochemical cues on the micro- and nanometer scale controls numerous cellular processes such as spreading, adhesion, migration, and proliferation. Using force microscopy we show that the lateral spacing of individual integrin receptor-ligand bonds determines the strength of cell adhesion. For spacings > or = 90 nm, focal contact formation was inhibited and the detachment forces as well as the stiffness of the cell body were significantly decreased compared to spacings < or = 50 nm. Analyzing cell detachment at the subcellular level revealed that rupture forces of focal contacts increase with loading rate as predicted by a theoretical model for adhesion clusters. Furthermore, we show that the weak link between the intra- and extracellular space is at the intracellular side of a focal contact. Our results show that cells can amplify small differences in adhesive cues to large differences in cell adhesion strength.

Force-induced destabilization of focal adhesions at defined integrin spacings on nanostructured surfaces

Focal adhesions are the anchoring points of cells to surfaces and are responsible for a large number of surface sensing processes. Nanopatterning studies have shown physiological changes in fibroblasts as a result of decreasing density of external binding ligands. The most striking of these changes is a decreased ability to form mature focal adhesions when lateral ligand distances exceed 76 nm. These changes are usually examined in the context of protein signaling and protein interactions. We show a physical explanation based on the balance between the forces acting on individual ligand connections and the reaction kinetics of those ligands. We propose three stability regimes for focal adhesions as a function of ligand spacing and applied stress: a stable regime, an unstable regime in which a large fraction of unbound protein causes adhesion disintegration, and a regime in which the applied force is too high to form an adhesion structure.

Soluble amyloid precursor proteins in the cerebrospinal fluid as novel potential biomarkers of Alzheimer's disease: a multicenter study

In this report, we present the results of a multicenter study to test analytic and diagnostic performance of soluble forms of amyloid precursor proteins alpha and beta (sAPP alpha and sAPP beta) in the cerebrospinal fluid (CSF) of patients with different forms of dementing conditions. CSF samples were collected from 188 patients with early dementia (mini-mental state examination >or=20 in majority of cases) and mild cognitive impairment (MCI) in 12 gerontopsychiatric centers, and the clinical diagnoses were supported by neurochemical dementia diagnostic (NDD) tools: CSF amyloid beta peptides, Tau and phospho-Tau. sAPP alpha and sAPP beta were measured with multiplexing method based on electrochemiluminescence. sAPP alpha and sAPP beta CSF concentrations correlated with each other with very high correlation ratio (R=0.96, P<0.001). We observed highly significantly increased sAPP alpha and sAPP beta CSF concentrations in patients with NDD characteristic for Alzheimer's disease (AD) compared to those with NDD negative results. sAPP alpha and sAPP beta highly significantly separated patients with AD, whose diagnosis was supported by NDD findings (sAPP alpha: cutoff, 117.4 ng ml(-1), sensitivity, 68%, specificity, 85%, P<0.001; sAPP beta: cutoff, 181.8 ng ml(-1), sensitivity, 75%, specificity, 85%, P<0.001), from the patients clinically assessed as having other dementias and supported by NDD untypical for AD. We conclude sAPP alpha and sAPP beta might be regarded as novel promising biomarkers supporting the clinical diagnosis of AD.

[Regulation of emotions and alexithymia: a correlative study]

This study assessed the correlations between Alexithymia and the recognition and regulation of emotions in a sample of healthy subjects. The first focus was on the relation between self-rated alexithymia (TAS-20) and objectively measured emotion recognition ability from faces and scenic descriptions of social interactions. Furthermore expressive suppression as a means of emotion regulation was related to alexithymia. Using the new factorial structure for the German version of the TAS-20, we were able to show differential effects: Objectively assessed emotion recognition correlated negatively with external thinking and positively with the importance of emotional introspection, but not with the core of alexithymia, particularly difficulties identifying and describing emotions. Expressive suppression on the other hand correlated mainly with this central feature of alexithymia. This overlap of constructs suggests to including complementary test in the assessment of alexithymia.

Amyloid beta peptides in plasma in early diagnosis of Alzheimer's disease: A multicenter study with multiplexing

We measured concentrations of Abeta peptides 1-42 and 1-40, and their ratio in plasma of patients carefully categorized clinically and neurochemically as having AD or other dementias with a newly commercially available multiplexing assay, characterized by reasonable laboratory performance (intra-assay imprecision in the range of 1.3-3.8% for Abeta1-42, and 1.8-4.1% for Abeta1-40, inter-assay imprecision for Abeta1-42, Abeta1-40, and Abeta1-42/Abeta1-40 concentration ratio in the range of 2.3-11.5%, 2.2-10.4% and 4.2-9.7%, respectively). Patients with AD or mild cognitive impairment of AD type (MCI-AD) whose clinical diagnosis was supported with CSF biomarkers (n=193) had significantly lower Abeta1-42 plasma concentrations (p<0.007), and Abeta1-42/1-40 ratios (p<0.003) compared to patients with other dementias and MCI of other types (n=64). No significant differences between persons with MCI of AD type and patients with early AD were observed, or between MCI of other types versus patients with early dementia of other types. Our findings reconfirm the hypothesis that alterations of biomarker concentrations occur early in a preclinical AD stage and that these alterations are also reflected in plasma.

Emotion Regulation Questionnaire – Eine deutschsprachige Fassung des ERQ von Gross und John

Zusammenfassung. Eines der ersten validierten Instrumente zur wissenschaftlichen Untersuchung von Emotionsregulationsprozessen, stellt der englischsprachige Emotion Regulation Questionnaire (ERQ) von Gross und John (2003) dar. Dieser erlaubt es, Präferenzen für zwei häufig angewandte Strategien zur Emotionsregulation, nämlich Unterdrückung (suppression) und Neubewertung (reappraisal) zu erfassen. Die deutsche Version wurde in drei Übersetzungsschritten an jeweils einer Gruppe von Studenten (n = 113/167/174) erprobt. Dabei stand eine möglichst enge Orientierung am englischen Original sowie die Optimierung der Faktoren-Ladungen auf die zwei Komponenten im Vordergrund. Eine Faktorenanalyse mit iterativer Kommunalitätenschätzung und Varimax-Rotation wurde verwendet. Entsprechend unserem Ziel erreichten die Alpha-Werte (innere Konsistenz) als Reliabilitätsmaß für Unterdrückung und Neubewertung die Durchschnittswerte des amerikanischen Originalfragebogens. Wir entwickelten ein Instrument, das einfach und in kurzer Zeit (5–10 min) zu beantworten ist und differenziert die beiden Emotionsregulationsstile Neubewertung und Suppression erfasst. Mögliche Anwendungsbereiche sind die Untersuchung von Depressionen und Angsterkrankungen und die Bewertung psychotherapeutischer Verfahren.

Facial emotion recognition and alexithymia in adults with somatoform disorders

OBJECTIVE

The primary aim of this study was to investigate facial emotion recognition in patients with somatoform disorders (SFD). Also of interest was the extent to which concurrent alexithymia contributed to any changes in emotion recognition accuracy.

METHODS

Twenty patients with SFD and twenty healthy, age, sex and education matched, controls were assessed with the Facially Expressed Emotion Labelling Test of facial emotion recognition and the 26-item Toronto Alexithymia Scale (TAS-26).

RESULTS

Patients with SFD exhibited elevated alexithymia symptoms relative to healthy controls. Patients with SFD also recognized significantly fewer emotional expressions than did the healthy controls. However, the group difference in emotion recognition accuracy became nonsignificant once the influence of alexithymia was controlled for statistically.

CONCLUSIONS

This suggests that the deficit in facial emotion recognition observed in the patients with SFD was most likely a consequence of concurrent alexithymia. Impaired facial emotion recognition observed in the patients with SFD could plausibly have a negative influence on these individuals' social functioning.

Facial emotion recognition and alexithymia in adults with somatoform disorders

The primary aim of this study was to investigate facial emotion recognition (FER) in patients with somatoform disorders (SFD). Also of interest was the extent to which concurrent alexithymia contributed to any changes in emotion recognition accuracy. Twenty patients with SFD and 20 healthy, age, sex and education matched, controls were assessed with the Facially Expressed Emotion Labelling Test of FER and the 26-item Toronto Alexithymia Scale. Patients with SFD exhibited elevated alexithymia symptoms relative to healthy controls. Patients with SFD also recognized significantly fewer emotional expressions than did the healthy controls. However, the group difference in emotion recognition accuracy became nonsignificant once the influence of alexithymia was controlled for statistics. This suggests that the deficit in FER observed in the patients with SFD was most likely a consequence of concurrent alexithymia. It should be noted that neither depression nor anxiety was significantly related to emotion recognition accuracy, suggesting that these variables did not contribute the emotion recognition deficit. Impaired FER observed in the patients with SFD could plausibly have a negative influence on these individuals' social functioning.

Symmetries in a standardized set of emotional facial expressions (JACFEE)

OBJECTIVE

To investigate possible asymmetry in a widely used set of standardized emotional facial expressions (JACFEE, Japanese and Caucasian Facial Expressions of Emotion).

METHOD

Chimeric pictures with either two left (LL) or two right (RR) halves of the emotional face were produced from the original set and presented to healthy subjects who rated their intensity.

RESULTS

With the exception of "happiness", for all other emotions (sadness, disgust, anger, fear and surprise) LL and RR composites were given comparable intensities, speaking for high symmetry in the faces.

CONCLUSIONS

The JACFEE facial emotion pictures are mostly symmetrical, possibly due to their standardisation procedure when producing the pictures.

Introduction of functional groups into peptides via N-alkylation

An optimized protocol for the mild and selective Fukuyama-Mitsunobu reaction was used for mono- and di- N-alkylation on solid support. Thereby, nonfunctionalized aliphatic and aromatic residues are quickly introduced into transiently protected, primary amines of a linear peptide. N-Alkylation can also be used to implement alkyl chains carrying (protected) functionalities suited for subsequent modification. Applicability of this method is demonstrated by various N-alkylated analogues of a cyclic CXCR4 receptor antagonist originally developed by Fujii et. al.

Efficient factor VIII affinity purification using a small synthetic ligand

BACKGROUND

Hemophilia A is currently treated by infusions of the coagulation factor (F) VIII, of which production and purification remain a challenging task. Current purification procedures using immunoaffinity chromatography are cumbersome, expensive, and suffer from the instability of the applied antibody ligands, which elute along with the product and contaminate it. Recently, FVIII was purified using octapeptide ligands, but their use is limited due to the low resistance to proteases.

OBJECTIVE

Our goal was to develop and evaluate a novel ligand for FVIII purification, overcoming the drawbacks of current procedures.

METHODS

Peptide ligands were screened for binding of (125)I-plasma-derived-FVIII (pdFVIII) in a microbead assay. A selected ligand-coated Toyopearl resin was then used for pdFVIII purification from cell-conditioned Delbucco's modified Eagle's medium (DMEM) containing fetal bovine serum. The proteolytic stability of ligand was measured by incubating with human serum and proteinase K, and its cytotoxicity towards human OV-MZ-6 cells was assayed.

RESULTS

A high-affinity octapeptidic FVIII ligand was modified into the small, highly stable and non-toxic peptidomimetic ligand L4 by rational and combinatorial design without affecting its affinity for FVIII. Using ligand L4-coated Toyopearl resin, pdFVIII was isolated from cell-conditioned medium with high purity and 89% column retention after elution with a mild buffer containing 0.6 m NaCl at pH 6.8.

CONCLUSIONS

Ligand L4 offers a valuable alternative to antibody-based procedures for laboratory and industrial production. Its synthesis by established solid-phase procedures is straightforward and considerably cheaper than the biotechnological production of antibodies, and safety concerns associated with the use of biological material are overcome.