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Scanning force microscopy (SFM) is one of the most widely used techniques in biomaterials research. In addition to imaging the materials of interest, SFM enables the mapping of mechanical properties and biological responses with sub-nanometer resolution and piconewton sensitivity. This review aims to give an overview of using the scanning force microscope (SFM) for investigations on dental materials. In particular, SFM-derived methods such as force–distance curves (scanning force spectroscopy), lateral force spectroscopy, and applications of the FluidFM® will be presented. In addition to the properties of dental materials, this paper reports the development of the pellicle by the interaction of biopolymers such as proteins and polysaccharides, as well as the interaction of bacteria with dental materials. [ABSTRACT FROM AUTHOR]

In plant cell culture technology, plant cells grow in large agglomerates. For various investigations, however, single cells are required. One important parameter is the adhesion strength of single cells to surfaces or to each other. Hereby, e.g. the influence of the surface material and structure is of interest. To assess the adhesion forces of single cells to a surface, measurements with an atomic force microscope (AFM) can be applied. In the case of the plant cells Ocimum basilicum CMC, these cells grow as large cell agglomerates, so that a direct AFM single cell measurement is not possible. By developing a suitable cell separation method, it was possible to obtain vital single cells of the Ocimum basilicum CMC type and also to carry out adhesion measurements of these cells on a glass surface. No explicit methods for cell separation of plant cell cultures could be found in the literature. This method is therefore a new innovation that could also be used for other cell lines. [ABSTRACT FROM AUTHOR]

Neutral polysaccharides, such as bacterial dextrans, are one of the main components of the oral conditioning film, which is the first step in the formation of microbial biofilms on dental materials in the oral cavity. Although they play an essential role alongside proteins, their adhesion mechanisms are still very unknown. Therefore, they are currently being studied using various analytical methods. In particular, by means of scanning force spectroscopy (SFS), the adhesion forces are to be measured as a function of multiple parameters such as pH value or surface material. Cantilever tips must therefore be modified with the polysaccharide of interest. A stable coupling of dextran, which serves as a model polysaccharide here, can be achieved by a photochemical modification method, which is verified by fluorescence microscopy, X‐ray photoelectron spectroscopy, scanning force microscopy, and SFS. [ABSTRACT FROM AUTHOR]

'Candidatus Phytoplasma mali' ('Ca. P. mali') has only one major membrane protein, the immunodominant membrane protein (Imp), which is regarded as being close to the ancestor of all phytoplasma immunodominant membrane proteins. Imp binds to actin and possibly facilitates its movement in the plant or insect host cells. However, protein sequences of Imp are quite diverse among phytoplasma species, thus resulting in difficulties in identifying conserved domains across species. In this work, we compare Imp protein sequences of 'Ca. P. mali' strain PM19 (Imp-PM19) with Imp of different strains of 'Ca. P. mali' and identify its actin-binding domain. Moreover, we show that Imp binds to the actin of apple (Malus x domestica), which is the host plant of 'Ca. P. mali'. Using molecular and scanning force spectroscopy analysis, we find that the actin-binding domain of Imp-PM19 contains a highly positively charged amino acid cluster. Our result could allow investigating a possible correlation between Imp variants and the infectivity of the corresponding 'Ca. P. mali' isolates. [ABSTRACT FROM AUTHOR]

In nanobiotechnology, viral nanoparticles have come into focus as interesting nano building blocks. In this context, the formation of 2D and 3D structures is of particular interest. Herein, the creation of defined 2D patterns of an icosahedral plant virus, the tomato bushy stunt virus (TBSV), by means of different techniques is reported on: the top‐down lithography ebeam and focused ion beam (FIB) as well as the bottom‐up fluidic force microscope (FluidFM) approach. The obtained layer structures are imaged by scanning force and scanning electron microscopy. The data show that a defined 2D structure can successfully be created either top down by FIB or bottom up by FluidFM. Electron beam lithography is not able to remove viruses from the substrate under the chosen conditions. FIB has an advantage if larger areas covered with viruses combined with smaller areas without being desired. FluidFM is advantageous if only small areas with viruses are required. A further benefit is that the uncovered areas are not affected. The pattern formation in FluidFM is influenced not only by the spotting parameters, but in particular by the drying process. Deegan and Marangoni effects are shown to play a role if the spotted droplets are not very small. [ABSTRACT FROM AUTHOR]

Temperamental traits as ascertained by the Temperament Evaluation of Memphis, Pisa, Paris and San Diego Auto-Questionnaire (TEMPS-A) have been suggested as promising intermediate phenotypes of mental disorders. In anxiety disorders, however, TEMPS scales and their genetic underpinnings are still understudied. TEMPS-A scores in 109 patients with panic disorder (PD) were compared to a sample of 536 healthy probands. All participants were genotyped for serotonin transporter gene variation (5-HTTLPR/rs25531). PD patients displayed significantly increased scores on the dysthymic, cyclothymic, irritable and anxious subscales, and lower scores on the hyperthymic subscale, respectively (all ps < 0.001) compared to healthy probands. In the total sample, the less active 5-HTTLPR/rs25531 S/LG alleles were associated with higher scores on the dysthymic, cyclothymic, irritable and anxious temperaments (all ps < 0.01), but not the hyperthymic subscale. Mediation analyses revealed anxious temperament in particular to mediate the relationship between 5-HTT genotype and PD. Dysthymic, cyclothymic, irritable and notably anxious temperament could serve as valuable intermediate phenotypes in efforts to unravel neurobiological, particularly serotonin system related genetic pathomechanisms associated with PD and potentially contribute to a panel of vulnerability markers guiding early targeted preventive interventions. [ABSTRACT FROM AUTHOR]

Objectives: Childhood emotional neglect (EN) is a predictor for the development of affective disorders. Oxytocin (OXT) may mediate the interplay between EN and changes in stress biological systems, brain development, and mental health outcomes. We investigated, in a cross-sectional study, the associations between EN, (epi)genetic variation in the OXT receptor (OXTR) gene, and amygdalar and hippocampal volumes, two brain regions implicated in emotional processing. Methods: We recruited 63 Caucasian South African adults (35 women) with and without social anxiety disorder. Childhood EN was assessed using the Childhood Trauma Questionnaire. rs53576 and rs2254298 genotypes, as well as methylation status, was determined using DNA purified from whole blood. Bilateral amygdalar and hippocampal volumes were determined by structural magnetic resonance imaging. The relationships between these variables were investigated using linear regression. Results: The interaction of the rs2254298 A risk allele and EN was nominally associated with reduced left hippocampal volume. The rs2254298 A risk allele was independently associated with reduced bilateral amygdalar volumes. We found no association between EN, OXTR methylation and amygdalar or hippocampal volumes. The rs53576 GG risk genotype was, however, associated with decreased OXTR methylation. Conclusions: The rs2254298 A allele may increase susceptibility to the structural brain effects of EN. [ABSTRACT FROM AUTHOR]

The FluidFM enables the immobilization of single cells on a hollow cantilever using relative underpressure. In this study, we systematically optimize versatile measurement parameters (setpoint, z-speed, z-length, pause time, and relative underpressure) to improve the quality of force-distance curves recorded with a FluidFM. Using single bacterial cells (here the gram negative seawater bacterium Paracoccus seriniphilus and the gram positive bacterium Lactococcus lactis), we show that Single Cell Force Spectroscopy experiments with the FluidFM lead to comparable results to a conventional Single Cell Force Spectroscopy approach using polydopamine for chemical fixation of a bacterial cell on a tipless cantilever. Even for the bacterium Lactococcus lactis, which is difficult to immobilze chemically (like seen in an earlier study), immobilization and the measurement of force-distance curves are possible by using the FluidFM technology. [ABSTRACT FROM AUTHOR]

Depression and anxiety are common in childhood and adolescence. Even though cardinal symptoms differ, there is a considerable overlap regarding the pathogenic influence of serotonergic innervation, negative life experience, disturbed emotion perception/affect regulation, and impaired neural functioning in the fronto-limbic circuit. In this study, we examined the effect of the 5-HTTLPR/rs25531 genotype on depressive symptoms and trait anxiety under the consideration of the amount of negative life events in healthy children and adolescents (N = 389). In a subsample of 49 subjects, we performed fMRI to add fronto-limbic brain activation as a second interacting factor. Across all subjects, negative life events moderated the influence of the 5-HTTLPR/rs25531 genotype on both depressive symptoms and trait anxiety. In the fMRI subsample, 5-HTTLPR/rs25531 S + S/LG + S/LA + LGLA + LGLG genotype-associated left middle frontal gyrus (MFG) activation mediated the influence of 5-HTTLPR/rs25531 genotype on depressive symptoms, however, only in combination with negative life events. Genetic influence on trait anxiety was predominantly mediated by negative life events; only LALA genotype-specific activation in the right MFG worked as a mediator in combination with negative life events. The present findings hint towards distinct mechanisms mediating the influence of 5-HTTLPR/rs25531 genotype on depressive symptoms and anxiety, with negative life events playing a crucial role in both phenotypes. With regard to depressive symptoms, however, this influence was only visible in combination with MFG activation, whereas, in anxiety, it was independent of brain activation. [ABSTRACT FROM AUTHOR]

Background and objectives: Although approaches combining behavioral genetics and neuroeconomics have advanced models of addiction, no study has synthesized these methods to elucidate mechanisms of competing risk-approachand risk-avoidance in social anxiety (SA). Grounded in dual-mode models of serotonergic systems and self-regulation, this study investigated associations between SA, serotonin transporter 5-HTT (LPR; rs25531) and receptor 5-HT1A genes, and risk-taking on behavioral and self-report measures.Design and methods: Young adults (N = 309) completed a neuroeconomic task measuring gambling attractiveness (δ), reward probability discrimination (γ), and risk attitudes (α). Risk genotypes included 5-HTT (LPR; rs25531) low-expression variants (SS/SLG/LGLG), and 5-HT1A (rs6295) GG.Results: Path analysis revealed that SA related to increased gambling attractiveness, but only for 5-HT1A risk groups. Although the 5-HTT (LPR; rs25531) risk genotypes and self-reported SA predicted lower social risk-taking, high-SA individuals who exhibited more accurate reward probability discrimination (γ) reported taking increased social risks.Conclusion: In line with dual-mode models, results suggest that SA predicts behavioral risk-approach at the basic decision-making level, along with self-reported social risk-avoidance, modulated by serotonergic genotypes. High-SA individuals with more accurate assessments of reward probabilities may engage in greater social risk-taking, perhaps reflecting an adaptive tendency to approach feared situations. [ABSTRACT FROM AUTHOR]

Preliminary evidence suggests that BDNF (brain derived neurotrophic factor) rs6265 genetic polymorphism, BDNF gene promotor methylation and BDNF serum levels might play an important role in the pathogenesis of affective disorders. As studies testing the BDNF system across molecular levels are sparse, this study aimed at investigating the BDNF val66met genotype, BDNF DNA methylation changes and peripheral BDNF serum levels in acute and remitted phases of MDD (major depressive disorder) and BD (bipolar disorder) and healthy controls. We found a significant difference of methylation levels at CpG site 1-1-1 and 3-1-1 between MDD and healthy controls (p < 0.003) with MDD patients showing significantly higher methylation levels. CpG 5-2-1 revealed a statistically significant difference between MDD and healthy controls and MDD and BD (p = 0.00003). Similar to the results of the methylation analysis a significant difference between MDD and healthy controls was found in BDNF serum levels (p = 0.002) with significantly lower BDNF serum levels in MDD compared to healthy controls. A difference between the samples from admission and discharge from hospital of both BDNF gene methylation and serum levels could not be detected in the present study and no influence of the BDNF val66met genotype on neither methylation nor BDNF serum level. [ABSTRACT FROM AUTHOR]

Bacterial cell appendix formation supports cell‐cell interaction, cell adhesion and cell movement. Additionally, in bioelectrochemical systems (BES), cell appendages have been shown to participate in extracellular electron transfer. In this work, the cell appendix formation of Clostridium acetobutylicum in biofilms of a BES are imaged and compared with conventional biofilms. Under all observed conditions, the cells possess filamentous appendages with a higher number and density in the BES. Differences in the amount of extracellular polymeric substance in the biofilms of the electrodes lead to the conclusion that the cathode can be used as electron donor and the anode as electron acceptor by C. acetobutylicum. When using conductive atomic force microscopy, a current response of about 15 nA is found for the cell appendages from the BES. This is the first report of conductivity for clostridial cell appendices and represents the basis for further studies on their role for biofilm formation and electron transfer. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this investigation was to examine the changes in wettability of dental impression materials during setting. This study compared the properties of the initial water contact of two different dental impression materials and their subsequent development during polymerization. Materials and Methods: Two dental impression materials (Impregum Penta Soft and Aquasil) with different chemical compositions (polyether and polyvinyl siloxane, respectively) were investigated with respect to their changing wetting properties by time-resolved static contact angle measurements. Ten sets of measurements each were taken over a period of 400 seconds with 150 points of data each; the first pictures were used for further characterization of the initial interaction. Results: With 73 degrees, Impregum Penta Soft exhibited a significantly lower contact angle, which stayed lower during the process of setting, compared to the silicone-based material. The initial interaction of the droplet showed a repulsive interaction of Aquasil with the water droplet. Conclusion: Impregum Penta Soft showed a more hydrophilic behavior during the process of setting compared to Aquasil and can therefore be expected to exhibit better flow properties. The method of time-resolved static contact angle measurements is a well-suited analytic instrument to monitor temporally changing wetting phenomena. [ABSTRACT FROM AUTHOR]

Ultrathin films of tetracyanoethylene (TCNE) on Co(100) were investigated by means of spin-integrated and spin-resolved photoemission spectroscopy ((sp-)UPS), X-ray photoemission spectroscopy (XPS), near edge X-ray absorption fine-structure spectroscopy (NEXAFS), and X-ray magnetic circular dichroism (XMCD). We found a coverage-dependent modulation of the interface dipole and a switching between a metallic and a resistive spin filtering at the interface triggered by two distinct adsorption geometries of TCNE. The strongest hybridization and spin structure modifications are found at low coverage with a face-on adsorption geometry indicating changes in the distance between the surface Co atoms beneath. TCNE has the potential to manipulate the magnetic moments in the Co surface itself, including the possibility of magnetic hardening effects. In summary, the system TCNE/Co offers an experimentally rather easy and controllable way to build up a stable molecular platform stabilizing the reactive ferromagnetic Co surface and customizing the electronic and magnetic properties of the resulting spinterface simultaneously. This makes this system very attractive for spintronic applications as an alternative, less reactive but highly spin polarized foundation beside graphene-based systems. [ABSTRACT FROM AUTHOR]

Imaging of biofilms on opaque surfaces is a challenge presented to researchers especially considering pathogenic bacteria, as those typically grow on living tissue, such as mucosa and bone. However, they can also grow on surfaces used in industrial applications such as food production, acting as a hindrance to the process. Thus, it is important to understand bacteria better in the environment they actually have relevance in. Stainless steel and titanium substrata were line structured and dotted surface topographies for titanium substrata were prepared to analyze their effects on biofilm formation of a constitutively green fluorescent protein (GFP)‐expressing Escherichia coli strain. The strain was batch cultivated in a custom built flow cell initially for 18 h, followed by continuous cultivation for 6 h. Confocal laser scanning microscopy (CLSM) was used to determine the biofilm topography. Biofilm growth of E. coli GFPmut2 was not affected by the type of metal substrate used; rather, attachment and growth were influenced by variable shapes of the microstructured titanium surfaces. In this work, biofilm cultivation in flow cells was coupled with the most widely used biofilm analytical technique (CLSM) to study the time course of growth of a GFP‐expressing biofilm on metallic surfaces without intermittent sampling or disturbing the natural development of the biofilm. [ABSTRACT FROM AUTHOR]

Background: Schizophrenic disorders are common and debilitating due to their symptoms, which can include delusions, hallucinations, and other negative symptoms. Organic forms can result from various cerebral disorders. In this paper, we discuss a potential association between schizophrenia and hereditary polyneuropathies (PNPs). Case presentation: We present the case of a 55-year-old female patient with chronically paranoid–hallucinatory schizophrenia, severe cognitive deficits since the age of 30, and comorbid repeated focal pressure neuropathies beginning at age 20. At the age of 35, genetic testing revealed a deletion on chromosome 17p12 covering the peripheral myelin protein 22 gene (PMP22), which led to the diagnosis of hereditary neuropathy with liability to pressure palsy (HNPP). Cerebral magnetic resonance imaging showed internal atrophy, magnetic resonance spectroscopy found alteration of the glutamate and myo-inositol levels in the anterior cingulate cortex, neuropsychological testing showed deficits in working memory and psychomotor speed, and electrophysiological testing detected signs of sensorimotor demyelinating PNP (accentuated in the legs). Conclusion: There may be an association between schizophrenia and HNPP. In observational studies, the deletion of interest (chromosome 17p12) was nearly 10 times more common in schizophreniform patients than in controls. This potential association could be pathophysiologically explained by the role of PMP22, which is mainly expressed in the peripheral nervous system. However, PMP22 mRNA and protein can also be found in the brain. PMP22 seems to play an important role in regulating cell growth and myelination, functions that are disturbed in schizophrenia. Such a connection obviously cannot be clarified on the basis of one case. Future studies should analyze whether patients with HNPP exhibit increased rates of psychotic disorders, and patients with schizophrenia and repeated focal pressure neuropathies should be examined for the PMP22 mutation. Alternatively, the co-occurrence of schizophrenia and HNPP could be coincidental. [ABSTRACT FROM AUTHOR]

Background: Mitochondrial diseases are caused by dysfunctions in mitochondrial metabolic pathways. MELAS syndrome is one of the most frequent mitochondrial disorders; it is characterized by encephalopathy, myopathy, lactic acidosis, and stroke-like episodes. Typically, it is associated with a point mutation with an adenine-to-guanine transition at position 3243 of the mitochondrial DNA (mtDNA; m.3243A>G) in the mitochondrially encoded tRNA leucine 1 (MT-TL1) gene. Other point mutations are possible and the association with polyglandular autoimmune syndrome type 2 has not yet been described. Case presentation: We present the case of a 25-year-old female patient with dysexecutive syndrome, muscular fatigue, and continuous headache. Half a year ago, she fought an infection-triggered Addison crisis. As the disease progressed, she had two epileptic seizures and stroke-like episodes with hemiparesis on the right side. Cerebral magnetic resonance imaging showed a substance defect of the parieto-occipital left side exceeding the vascular territories with a lactate peak. The lactate ischemia test was clearly positive, and a muscle biopsy showed single cytochrome c oxidase-negative muscle fibers. Genetic testing of blood mtDNA revealed a heteroplasmic base exchange mutation in the mitochondrially encoded NADH:ubiquinone oxidoreductase core subunit 4 (MT-ND4) gene (m.12015T>C; p.Leu419Pro; heteroplasmy level in blood 12%, in muscle tissue: 15%). The patient suffered from comorbid autoimmune polyglandular syndrome type 2 with Hashimoto's thyroiditis, Addison's disease, and autoimmune gastritis. In addition, we found increased anti-glutamic acid decarboxylase 65, anti-partial cell, anti-intrinsic factor, and anti-nuclear antibodies. Conclusion: We present an atypical case of MELAS syndrome with predominant symptoms of a dysexecutive syndrome, two stroke-like episodes, and fast-onset fatigue. The symptoms were associated with a not yet described base and aminoacid exchange mutation in the MT-ND4 gene (m.12015T>C to p.Leu419Pro). The resulting changed protein complex in our patient is part of the respiratory chain multicomplex I and might be the reason for the mitochondriopathy. However, different simulations for pathogenetic relevance are contradictory and rather speak for a benign variant. To our knowledge this case report is the first reporting MELAS syndrome with comorbid polyglandular autoimmune syndrome type 2. Screening for autoimmune alterations in those patients is important to prevent damage to end organs. [ABSTRACT FROM AUTHOR]

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Epigenetic processes such as DNA methylation are considered key mechanisms at the crossroads between genetics and environment in the etiology of mental disorders. The monoamine oxidases A and B (MAOA/MAOB) are prime candidates for the investigation into the role of DNA methylation in mental disorders, given their pivotal role in the metabolism of monoamines and as pharmacological targets of potent antidepressant drugs such as tranylcypromine, phenelzine or moclobemide. The present mini-review aims at summarizing and critically discussing the growing body of the literature supporting a role of DNA methylation of the MAOA gene promoter/exon I/intron I region and its interaction with environmental factors in several mental disorders, i.e., anxiety disorders, depression, posttraumatic stress disorder, substance use disorder, conduct disorder/antisocial personality disorder, borderline personality disorder and schizophrenia, as well as some pilot data on MAOB methylation in smokers and patients with borderline personality disorder. Furthermore, first evidence for MAOA methylation to be involved in treatment response prediction and as a potential mechanistic correlate of fear extinction is presented. Altered MAOA gene DNA methylation emerges as a possible pathogenetically relevant epigenetic mechanism in mental disorders. Given robust replication and further functional characterization, MAOA methylation patterns might serve as a peripheral biomarker of disease risk and treatment response informing preventive and personalized therapeutic approaches in the future. [ABSTRACT FROM AUTHOR]

Bacteria in flowing media are exposed to shear forces exerted by the fluid. Before a biofilm can be formed, the bacteria have to attach to a solid surface and have to resist these shear forces. Here, the authors determined dislodgement forces of single Paracoccus seriniphilus bacteria by means of lateral force microscopy. The first measurement set was performed on very flat glass and titanium (both as very hydrophilic samples with water contact angles below 20°) as well as highly oriented pyrolytic graphite (HOPG) and steel surfaces (both as more hydrophobic surfaces in the context of biological interaction with water contact angles above 50°). The different surfaces also show different zeta potentials in the range between −18 and −108 mV at the measurement pH of 7. The second set comprised titanium with different RMS (root mean square) roughness values from a few nanometers up to 22 nm. Lateral forces between 0.5 and 3 nN were applied. For Paracoccus seriniphilus, the authors found as a general trend that the surface energy of the substrate at comparable roughness determines the detachment process. The surface energy is inversely proportional to the initial adhesion forces of the bacterium with the surface. The higher the surface energy (and the lower the initial adhesion force) is, the easier the dislodgement of the bacteria happens. In contrast, electrostatics play only a secondary role in the lateral dislodgement of the bacteria and may come only into play if surface energies are the same. Furthermore, the surface chemistry (glass, titanium, and steel as oxidic surfaces and HOPG as a nonoxidic surface) seems to play an important role because HOPG does not completely follow the above mentioned general trend found for the oxide covered surfaces. In addition, the roughness of the substrates (made of the same material) is limiting the lateral dislodgement of the bacteria. All examined structures with RMS roughness of about 8–22 nm on titanium prevent the bacteria from the lateral dislodgement compared to polished titanium with an RMS roughness of about 3 nm. [ABSTRACT FROM AUTHOR]

Epigenetic mechanisms have been proposed to mediate fear extinction in animal models. Here, MAOA methylation was analyzed via direct sequencing of sodium bisulfite-treated DNA extracted from blood cells before and after a 2-week exposure therapy in a sample of n = 28 female patients with acrophobia as well as in n = 28 matched healthy female controls. Clinical response was measured using the Acrophobia Questionnaire and the Attitude Towards Heights Questionnaire. The functional relevance of altered MAOA methylation was investigated by luciferase-based reporter gene assays. MAOA methylation was found to be significantly decreased in patients with acrophobia compared with healthy controls. Furthermore, MAOA methylation levels were shown to significantly increase after treatment and correlate with treatment response as reflected by decreasing Acrophobia Questionnaire/Attitude Towards Heights Questionnaire scores. Functional analyses revealed decreased reporter gene activity in presence of methylated compared with unmethylated pCpGfree_ MAOA reporter gene vector constructs. The present proof-of-concept psychotherapy-epigenetic study for the first time suggests functional MAOA methylation changes as a potential epigenetic correlate of treatment response in acrophobia and fosters further investigation into the notion of epigenetic mechanisms underlying fear extinction. [ABSTRACT FROM AUTHOR]

Carbohydrates, for example in form of polysaccharides such as dextran are essential components of all living organisms and are involved in cell and bacterial adhesion. The latter can lead to biofilms which may either cause diseases or are beneficial in biofilm reactors. To utilize effects of bound carbohydrates it is required to know under which conditions they bind to solid surfaces such as dental materials or biofilm reactor walls. For this purpose one interesting question is to which amount the polysaccharides bind to the surface under a predefined condition. However, the quantification of bound carbohydrates is very difficult. A well‐known method to quantify carbohydrates in solution is the phenol‐sulfuric acid (PSA) assay. Here, this method is adapted for bound carbohydrates. This modified PSA assay delivers reproducible results and does only need a small amount of reagents and carbohydrates. In the case of dextran bound on titanium as biomaterial it delivers the expected results, that is that higher concentrations lead to a higher adsorbed amount. [ABSTRACT FROM AUTHOR]

Force spectroscopy and especially single cell force spectroscopy with bacterial probes provide a powerful tool for the investigation of bacterial adhesion to different surfaces. Thereby, a crucial step is the immobilization of the bacteria on the cantilever. Until today, there have been developed versatile methods to attach bacteria to a cantilever, but only few studies compare these methods in a quantitative way. In this work, different functionalizations of the cantilever as well as two picking‐up parameters for three gram‐positive bacteria are evaluated. While there is no functionalization which works best for all of the bacteria, polydopamine, the adhesive protein Cell‐TakTM and a gas phase silanization in combination with an activation of the bacteria are the most promising candidates. Further, some general trends how the two investigated picking‐up parameters influence the adhesive behavior of the bacteria on the cantilever, which also depends strongly on the shape of the bacteria are presented. [ABSTRACT FROM AUTHOR]

Background: Schizophreniform syndromes can be divided into primary idiopathic forms as well as different secondary organic subgroups (e.g., paraepileptic, epileptic, immunological, or degenerative). Secondary epileptic explanatory approaches have often been discussed in the past, due to the high rates of electroencephalography (EEG) alterations in patients with schizophrenia. In particular, temporal lobe epilepsy is known to be associated with schizophreniform symptoms in well-described constellations. In the literature, juvenile myoclonic epilepsy has been linked to emotionally unstable personality traits, depression, anxiety, and executive dysfunction; however, the association with schizophrenia is largely unclear. Case presentation: We present the case of a 28-year-old male student suffering from mild myoclonic jerks, mainly of the upper limbs, as well as a predominant paranoid-hallucinatory syndrome with attention deficits, problems with working memory, depressive-flat mood, reduced energy, fast stimulus satiation, delusional and audible thoughts, tactile hallucinations, thought inspirations, and severe sleep disturbances. Cerebral magnetic resonance imaging and cerebrospinal fluid analyses revealed no relevant abnormalities. The routine EEG and the first EEG after sleep deprivation (under treatment with oxazepam) also returned normal findings. Video telemetry over one night, which included a partial sleep-deprivation EEG, displayed short generalized spike-wave complexes and polyspikes, associated with myoclonic jerks, after waking in the morning. Video-EEG monitoring over 5 days showed over 100 myoclonic jerks of the upper limbs, frequently with generalized spike-wave complexes with left or right accentuation. Therefore, we diagnosed juvenile myoclonic epilepsy. Discussion: This case report illustrates the importance of extended EEG diagnostics in patients with schizophreniform syndromes and myoclonic jerks. The schizophreniform symptoms in the framework of epileptiform EEG activity can be interpreted as a (para)epileptic mechanism due to local area network inhibition (LANI). Following the LANI hypothesis, paranoid hallucinatory symptoms are not due to primary excitatory activity (as myoclonic jerks are) but rather to the secondary process of hyperinhibition triggered by epileptic activity. Identifying subgroups of schizophreniform patients with comorbid epilepsy is important because of the potential benefits of optimized pharmacological treatment. [ABSTRACT FROM AUTHOR]

Background Posttraumatic stress disorder is characterized by an overactive noradrenergic system conferring core posttraumatic stress disorder symptoms such as hyperarousal and reexperiencing. Monoamine oxidase A is one of the key enzymes mediating the turnover of noradrenaline. Here, DNA methylation of the monoamine oxidase A gene exonI/intronI region was investigated for the first time regarding its role in posttraumatic stress disorder risk and severity. Methods Monoamine oxidase A methylation was analyzed via direct sequencing of sodium bisulfite-treated DNA extracted from blood cells in a total sample of N=652 (441 male) patients with current posttraumatic stress disorder, patients with remitted posttraumatic stress disorder, and healthy probands (comparison group) recruited at 5 centers in Bosnia-Herzegovina, Croatia, and the Republic of Kosovo. Posttraumatic stress disorder severity was measured by means of the Clinician-Administered Posttraumatic Stress Disorder Scale and its respective subscores representing distinct symptom clusters. Results In the male, but not the female sample, patients with current posttraumatic stress disorder displayed hypermethylation of 3 CpGs (CpG3=43656362; CpG12=43656514; CpG13=43656553, GRCh38.p2 Assembly) as compared with remitted Posttraumatic Stress Disorder patients and healthy probands. Symptom severity (Clinician-Administered Posttraumatic Stress Disorder Scale scores) in male patients with current posttraumatic stress disorder significantly correlated with monoamine oxidase A methylation. This applied particularly to symptom clusters related to reexperiencing of trauma (cluster B) and hyperarousal (cluster D). Conclusions The present findings suggest monoamine oxidase A gene hypermethylation, potentially resulting in enhanced noradrenergic signalling, as a disease status and severity marker of current posttraumatic stress disorder in males. If replicated, monoamine oxidase A hypermethylation might serve as a surrogate marker of a hyperadrenergic subtype of posttraumatic stress disorder guiding personalized treatment decisions on the use of antiadrenergic agents. [ABSTRACT FROM AUTHOR]

The bacterial attachment to surfaces is the first step of biofilm formation. This attachment is governed by adhesion forces which act between the bacterium and the substrate. Such forces can be measured by single cell force spectroscopy, where a single bacterium is attached to a cantilever of a scanning force microscope, and force-distance curves are measured. For the productive sea-water bacterium Paracoccus seriniphilus, pH dependent measurements reveal the highest adhesion forces at pH 4. Adhesion forces measured at salinities between 0% and 4.5% NaCl are in general higher for higher salinity. However, there is an exception for 0.9% where a higher adhesion force was measured than expected. These results are in line with zeta potential measurements of the bacterium, which also show an exceptionally low zeta potential at 0.9% NaCl. In the absence of macromolecular interactions, the adhesion forces are thus governed by (unspecific) electrostatic interactions, which can be adjusted by pH and ionic strength. It is further shown that microstructures on the titanium surface increase the adhesion force. Growth medium reduces the interaction forces dramatically, most probably through macromolecular bridging. [ABSTRACT FROM AUTHOR]

The bacterial attachment to surfaces is the first step of biofilm formation. This attachment is governed by adhesion forces which act between the bacterium and the substrate. Such forces can be measured by single cell force spectroscopy, where a single bacterium is attached to a cantilever of a scanning force microscope, and force-distance curves are measured. For the productive sea-water bacterium Paracoccus seriniphilus, pH dependent measurements reveal the highest adhesion forces at pH 4. Adhesion forces measured at salinities between 0% and 4.5% NaCl are in general higher for higher salinity. However, there is an exception for 0.9% where a higher adhesion force was measured than expected. These results are in line with zeta potential measurements of the bacterium, which also show an exceptionally low zeta potential at 0.9% NaCl. In the absence of macromolecular interactions, the adhesion forces are thus governed by (unspecific) electrostatic interactions, which can be adjusted by pH and ionic strength. It is further shown that microstructures on the titanium surface increase the adhesion force. Growth medium reduces the interaction forces dramatically, most probably through macromolecular bridging. [ABSTRACT FROM AUTHOR]

Plant viruses which are self-assembled on a substrate are interesting building blocks in nanobiotechnology, in particular, for the creation of 2D ordered structures. In this article, the self-assembly of different genetically modified types of the tomato bushy stunt virus spin-coated on pristine silicon was investigated by scanning force and scanning electron microscopy. Amino acid side chains were integrated in the capsids of the viruses by extending the coat protein with different charged amino acid clusters (tetra-aspartate-hexa-histidine, hexa-aspartate, or tetra-arginine-tags). The influence of the resulting electrostatic forces based on virus-virus and virus-surface interactions on the formation of self-assembled monolayers will be presented and discussed in the context of differences in surface coverage for different pH values. It could be shown that the largest surface coverage can be achieved when there is an attraction between the whole virus and the surface and only a minor repulsion between the viruses at a given pH. [ABSTRACT FROM AUTHOR]

Microorganisms growing in biofilms might be possible biocatalysts for future biotechnological production processes. Attached to a surface and embedded in an extracellular polymeric matrix, they create their preferred environment and form robust cultures for continuous systems. With the objective of implementing highly efficient processes, productive biofilms need to be understood comprehensively. In this study, the influence of microstructured metallic surfaces on biofilm productivity was researched. To conduct this study, titanium and stainless steel sheets were polished, micromilled, as well as coated with particles. Subsequently, the metal sheets were exposed to the lactic acid producing Lactobacillus delbrueckii subsp. lactis under laminar and homogeneous flow conditions in a custom-built flow cell. A proof-of-concept showed that biofilm formation in the system only occurred on the designated substratum. Following a 24-h batch cultivation for primary biofilm development, the culture was continuously provided with glucose containing medium. As different experimental series have indicated, the process resulted to be stable for up to eleven days. Primary metabolite productivity averaged around 6-7 g/(L h). Interestingly, the productivity was shown to be affected neither by the type of metal, nor by the applied microstructures. Nevertheless, a higher dry biomass weight determined on micro-milled substratum indicates a complementary differentiation of biofilm components in future experiments. [ABSTRACT FROM AUTHOR]

The influence of oxygen (and argon) plasma cleaning and a base-acid cleaning procedure on stainless steel surfaces was studied. The main aim was to clean stainless steel samples from Paracoccus seriniphilus biofilms without changing the surface properties which are relevant for bacterial attachment to allow reuse in a biofilm reactor. It is shown that oxygen plasma cleaning, which very successfully removes the same kind of biofilm from titanium surfaces, is not suitable for stainless steel. It largely influences the surface chemistry by producing thick metal oxide layers of varying compositions and changing phenomenological surface properties such as wettability. A promising method without changing surface properties while cleaning satisfactorily is a combination of base and acid reagents at elevated temperature. [ABSTRACT FROM AUTHOR]

Environmental vulnerability factors such as adverse childhood experiences in interaction with genetic risk variants, e.g., the serotonin transporter gene linked polymorphic region ( 5- HTTLPR), are assumed to play a role in the development of anxiety and affective disorders. However, positive influences such as general self-efficacy (GSE) may exert a compensatory effect on genetic disposition, environmental adversity, and anxiety traits. We, thus, assessed childhood trauma (Childhood Trauma Questionnaire, CTQ) and GSE in 678 adults genotyped for 5- HTTLPR/rs25531 and their interaction on agoraphobic cognitions (Agoraphobic Cognitions Questionnaire, ACQ), social anxiety (Liebowitz Social Anxiety Scale, LSAS), and trait anxiety (State-Trait Anxiety Inventory, STAI-T). The relationship between anxiety traits and childhood trauma was moderated by self-efficacy in 5- HTTLPR/rs25531 LL genotype carriers: LL probands maltreated as children showed high anxiety scores when self-efficacy was low, but low anxiety scores in the presence of high self-efficacy despite childhood maltreatment. Our results extend previous findings regarding anxiety-related traits showing an interactive relationship between 5- HTT genotype and adverse childhood experiences by suggesting coping-related measures to function as an additional dimension buffering the effects of a gene-environment risk constellation. Given that anxiety disorders manifest already early in childhood, this insight could contribute to the improvement of psychotherapeutic interventions by including measures strengthening self-efficacy and inform early targeted preventive interventions in at-risk populations, particularly within the crucial time window of childhood and adolescence. [ABSTRACT FROM AUTHOR]

The total amount of albumin and lysozyme adsorbed on different dentally relevant materials like titanium, gold, ceramics, poly(methyl methacrylate) (PMMA) and polytetrafluoroethylene (PTFE) was measured by bicinchoninic acid assay (BCA assay) after detachment of the proteins from the samples. The total amount of protein was separated into the amount of loosely and firmly adsorbed protein. The parts of loosely and firmly bound protein differ remarkably depending on the material. For albumin, the loosely bound protein dominates the total adsorption. In contrast, for lysozyme the amount of loosely and firmly bound protein is in some cases equal and sometimes there is more firmly than loosely bound lysozyme. In general, the firmly bound protein masks the electrostatics of the surface. The amount of loosely bound protein follows no strict tendency, whereas the amount of firmly bound protein is mostly governed by entropic and hydrophobic interactions, but modulated by electrostatics and thus by the isoelectric points of the surface and of the proteins. Most protein adsorbs on the metallic surfaces, if compared to the investigated non-metallic surfaces. For the adsorption on gold, the number of cysteines in the amino acid sequence influences the amount of protein on the gold surface. Least albumin adsorbs on PMMA, least lysozyme adsorbs on PMMA and PTFE. For albumin, pH depending conformational changes play a key role for the adsorption at pH 9.0. [ABSTRACT FROM AUTHOR]

Chloroperoxidase (CPO) is a versatile enzyme, which is secreted by the marine fungus Caldariomyces fumago ( Leptoxyphium fumago). However, the application of the enzyme is hampered by its high price, which is due to the costly, labor-intensive purification process. One challenge of the downstream process is the removal of a coproduced black pigment that forms a complex with the active enzyme. While strain development can be considered as an option to reduce the synthesis of the interfering pigment, the metabolism of the microorganism can be altered alternatively by using the biofilm growth mode of the fungus. The aim of this study was to reduce pigment formation during CPO synthesis. We investigated for the first time CPO production during C. fumago biofilm growth initiated through the presence of different microstructured stainless steel surfaces (material number: 1.4571; AISI 316Ti). CPO production by C. fumago was similar when grown as a biofilm or in suspension, whereas pigment formation was drastically reduced by cells grown on moderately structured surfaces ( Ra = 0.13 ± 0.02 μm). The possibilities of biofilm growth for changing cell properties and for continuous fermentation are discussed. [ABSTRACT FROM AUTHOR]

Social anxiety disorder (SAD) is a commonly occurring and highly disabling disorder. The neuropeptide oxytocin and its receptor (OXTR) have been implicated in social cognition and behavior. This study-for the first time applying a multilevel epigenetic approach-investigates the role of OXTR gene methylation in categorical, dimensional, and intermediate neuroendocrinological/neural network phenotypes of social anxiety. A total of 110 unmedicated patients with SAD and matched 110 controls were analyzed for OXTR methylation by direct sequencing of sodium bisulfite-converted DNA extracted from whole blood. Furthermore, OXTR methylation was investigated regarding SAD-related traits (Social Phobia Scale (SPS) and Social Interaction Anxiety Scale (SIAS)), salivary cortisol response during the Trier social stress test (TSST), and amygdala responsiveness to social phobia related verbal stimuli using fMRI. Significantly decreased OXTR methylation particularly at CpG Chr3: 8 809 437 was associated with (1) the categorical phenotype of SAD (p<0.001, Cohen's d=0.535), (2) increased SPS and SIAS scores (p<0.001), (3) increased cortisol response to the TSST (p=0.02), and (4) increased amygdala responsiveness during social phobia-related word processing (right: pcorr<0.001; left: pcorr=0.005). Assuming that decreased OXTR methylation confers increased OXTR expression, the present finding may reflect a compensatory upregulation for pathologically reduced oxytocin levels or a causally relevant increased OXTR activation in SAD and related traits. OXTR methylation patterns might thus serve as peripheral surrogates of oxytocin tone and aid in establishing accessible biomarkers of SAD risk allowing for indicated preventive interventions and personalized treatment approaches targeting the oxytocin system. [ABSTRACT FROM AUTHOR]

Plain and microstructured cp-titanium samples were studied as possible biofilm reactor substrates. The biofilms were grown by exposition of the titanium samples to bacteria in a flow cell. As bacteria the rod shaped gram negative Pseudomonas fluorescens and the spherical gram negative Paracoccus seriniphilus were chosen. Afterward, the samples were cleaned in subsequent steps: First, with a standard solvent based cleaning procedure with acetone, isopropanol, and ultrapure water and second by oxygen plasma sputtering. It will be demonstrated by means of x-ray photoelectron spectroscopy, fluorescence microscopy, and confocal laser scanning microscopy that oxygen plasma cleaning is a necessary and reliant tool to fully clean and restore titanium surfaces contaminated with a biofilm. The microstructured surfaces act beneficial to biofilm growth, while still being fully restorable after biofilm contamination. Scanning electron microscopy images additionally show, that the plasma process does not affect the microstructures. The presented data show the importance of the cleaning procedure. Just using solvents does not remove the biofilm and all its components reliably while a cleaning process by oxygen plasma regenerates the surfaces. [ABSTRACT FROM AUTHOR]

The measurement of force-distance curves on a single bacterium provides a unique opportunity to detect properties such as the turgor pressure under various environmental conditions. Marine bacteria are very interesting candidates for the production of pharmaceuticals, but are only little studied so far. Therefore, the elastic behavior of Paracoccus seriniphilus, an enzyme producing marine organism, is presented in this study. After a careful evaluation of the optimal measurement conditions, the spring constant and the turgor pressure are determined as a function of ionic strength and pH. Whereas the ionic strength changes the turgor pressure passively, the results give a hint that the change to acidic pH increases the turgor pressure by an active mechanism. Furthermore, it could be shown, that P. seriniphilus has adhesive protrusions outside its cell wall. [ABSTRACT FROM AUTHOR]

The monoamine oxidase A ( MAO- A) gene has been suggested to be involved in the pathogenesis as well as the pharmacological treatment of major depressive disorder. In the present analysis, for the first time a pharmacoepigenetic approach was applied investigating the influence of DNA methylation patterns in the MAO- A regulatory and exon1/intron1 region on antidepressant treatment response. 94 patients of Caucasian descent with major depressive disorder ( f = 61; DSM-IV) were analyzed for DNA methylation status at 43 MAO- A CpG sites via direct sequencing of sodium bisulfite treated DNA extracted from blood cells. Patients were also genotyped for the functional MAO- A VNTR. Clinical response to antidepressant treatment with escitalopram was assessed by intra-individual changes of HAM-D-21 scores after 6 weeks of treatment. Apart from two CpG sites, male subjects showed no or only very minor methylation. In female patients, lower methylation at two individual CpG sites in the MAO- A promoter region was nominally associated with impaired response to antidepressant treatment after 6 weeks (GRCh37/hg19: CpG 43.514.063, p = 0.04; CpG 43.514.684, p = 0.009), not, however, withstanding correction for multiple testing. MAO- A VNTR genotypes did not influence MAO- A methylation status. The present pilot data do not suggest a major influence of MAO- A DNA methylation on antidepressant treatment response. However, the presently observed trend towards CpG-specific MAO- A gene hypomethylation-possibly via increased gene expression and consecutively decreased serotonin and/or norepinephrine availability-to potentially drive impaired antidepressant treatment response in female patients might be worthwhile to be followed up in larger pharmacoepigenetic studies. [ABSTRACT FROM AUTHOR]

For a better understanding of biofilm establishment, adhesion forces of proteins on immobilized protein layers were investigated by scanning force spectroscopy (SFS). For this purpose the experimental setup to immobilize protein layers on the surface is important. The influence of the method chosen to immobilize the proteins on the surface was examined and afterwards the effect of variations in pH and contact time on the measured adhesion forces in protein-protein interaction was analyzed. The adsorption of bovine serum albumin (BSA) on BSA-coated silicon was used here as a model system. To coat the substrate, free adsorption, crosslinking with glutaraldehyde, and covalent protein binding to the surface after silanization were used. For the latter different deposition methods of the silane were compared. Depending on the immobilization method the measured protein-protein interactions show distinct differences. Covalent attachment of proteins is a promising approach to attain stable, pre-adsorbed protein layers for SFS measurements. The adhesion forces of a BSA-coated cantilever on such layers seem to be dominated by electrostatic interactions of the molecules. [ABSTRACT FROM AUTHOR]

Glass is one of the most important materials in medical packaging. Protein adsorption at the glass walls leads to loss of the active substance in the glass vials and thus to high costs for the pharmaceutical industry, in particular in the case of expensive drugs. Thus more knowledge about the basic mechanisms and the involved parameters in protein interaction with glass surfaces is desirable. In this context, the adsorption of bovine serum albumin (BSA), fibrinogen (FIB), and lysozyme (LYS) on typical glass surfaces (borosilicate glass, quartz glass) was investigated by dynamic contact angle (DCA) measurements as a function of pH value. DCA allows the determination of the relative amount of adsorbed protein and of the reversibility of the adsorption process. It will be shown that the amount of adsorbed protein is governed by electrostatics on quartz glass while on borosilicate glass no influence of the pH value (and hence the electrostatics) can be seen. This can be explained by the different surface composition which has apparently an important influence on the adsorption process. In addition it could be determined that on both glass surfaces, none of the investigated proteins shows a complete reversibility of the adsorption process, i.e., desorption is never complete. In conclusion the interaction with glass surfaces cannot be generalized but electrostatics play a major role and thus the interaction of proteins with glass surfaces may be changed by shifting the pH value of the solutions or the isoelectric point (IEP) of the surfaces. [ABSTRACT FROM AUTHOR]

The application of scanning force microscopy (SFM) in biology has increased during the last years because it allows measurements without pretreatment and under physiological conditions. In addition to pure imaging it is possible to use the SFM as a force sensor to detect forces as small as piconewtons. Such forces are relevant to interactions between bacterial cells and surfaces or biofilms on surfaces. Furthermore, the so-called mapping modes were recently developed as combinations of imaging and force spectroscopy modes. Especially in the field of biofilm formation the SFM allows to map biofilms, bacterial cells as well as cell properties by specifically applying functionalized or unfunctionalized tips. In this paper we provide a short survey of the opportunities of the SFM as a nano(mechanical) tool in the field of bacterial cell biology and want to provide practical advice for SFM on bacteria for beginners. The application of the scanning force microscope on bacterial cells. Mapping is a combination of the imaging and force spectroscopy application and can be performed with a functionalized or unfunctionalized cantilever. The single cell force spectroscopy can be performed either on adsorbed cells or on a naked surface. The image is not to scale. [ABSTRACT FROM AUTHOR]

The loosely and firmly adsorbed amount of bovine serum albumin (BSA) on dental titanium and dental gold was investigated by bicinchoninic acid assay (BCA assay). This method does not require special properties of the sample like a high reflectivity or conductivity and turns the BCA assay into a valuable tool to investigate a widespread spectrum of different substrate materials, e.g., natural enamel. The experiments in this work showed that it is possible to distinguish between loosely and firmly bound protein with the BCA assay. On the here investigated dental titanium and dental gold samples the amount of adsorbed BSA was dominated by the loosely bound part. On dental gold the total amount of adsorbed BSA was significantly higher than on titanium. The amount of loosely bound BSA was high near the isoelectric points of dental titanium and dental gold while the amount of firmly adsorbed BSA on dental titanium followed the electrostatics. At high pH values (pH 9.0) conformational changes of the BSA molecules played a key role in the adsorption process. [ABSTRACT FROM AUTHOR]

Protein adsorption is a field of huge interest in a number of application fields. Information on protein adhesion is accessible by a variety of methods. However, the results obtained are significantly influenced by the applied technique. The objective of this work was to understand the role of adhesion forces (obtained by scanning force spectroscopy, SFS) in the process of protein adsorption and desorption. In SFS, the protein is forced to and retracted from the surface, even under unfavorable conditions, in contrast to the natural situation. Furthermore, adhesion forces are correlated with adhesion energies, neglecting the entropic part in the Gibbs enthalpy. In this context, dynamic contact angle (DCA) measurements were performed to identify the potential of this method to complement SFS data. In DCA measurements, the protein diffuses voluntarily to the surface and information on surface coverage and reversibility of adsorption is obtained, including entropic effects (conformational changes and hydrophobic effect). It could be shown that the surface coverage (by DCA) of bovine serum albumin on dental materials correlates well with the adhesion forces (by SFS) if no hydrophobic surface is involved. On those, the entropic hydrophobic effect plays a major role. As a second task, the reversibility of the protein adsorption, i.e., the voluntary desorption as studied by DCA, was compared to the adhesion forces. Here, a correlation between low adhesion forces and good reversibility could be found as long as no covalent bonds were involved. The comparative study of DCA and SFS, thus, leads to a more detailed picture of the complete adsorption/desorption cycle. [ABSTRACT FROM AUTHOR]

The electronic structure of the interface between ferromagnetic cobalt and the organic semiconductors copper- (CuPc) and iron-phthalocyanine (FePc) was investigated by means of photoemission spectroscopy (UPS, IPES, and XPS). These metal-phthalocyanine (MePc) molecules have an open shell structure and are known to show promising properties for their use in organic spintronics. In spintronic devices, the interface between ferromagnetic electrode and the organic layer determines the spin injection properties and is hence important for the quality of, e.g., a possible spin-valve device. For this purpose, cobalt was deposited onto the MePcs, such as in devices with ferromagnetic top contacts. The reported investigations reveal a diffusion of cobalt into the organic layers and chemical reactions at the interface. [ABSTRACT FROM AUTHOR]

The valence band structure of different metal-phthalocyanines was investigated by comparing ultraviolet photoelectron spectra at different excitation energies with simulated spectra that take the different photoionization cross-sections at these energies into account. The Kohn-Sham eigenvalue spectra, derived from density functional theory calculations, using hybrid exchange-correlation functionals, were weighted with the photoionization coefficients in accordance with the used excitation energy. By applying these techniques, the differences in the photoelectron spectra using He I and He II radiation can be reproduced and investigated. It will be shown that the 3d-orbitals of the used metal central atom of these molecules have a major influence. The changes at different excitation energies were studied for Fe, Co, and Cu central atoms to describe the chemical tailoring effects. [ABSTRACT FROM AUTHOR]