Sequential host-bacteria and bacteria-bacteria interactions determine the microbiome establishment of Nematostella vectensis

BACKGROUND

The microbiota of multicellular organisms undergoes considerable changes during host ontogeny but the general mechanisms that control community assembly and succession are poorly understood. Here, we use bacterial recolonization experiments in Nematostella vectensis as a model to understand general mechanisms determining bacterial establishment and succession. We compared the dynamic establishment of the microbiome on the germfree host and on inert silicone tubes.

RESULTS

Following the dynamic reconstruction of microbial communities on both substrates, we show that the initial colonization events are strongly influenced by the host but not by the silicone tube, while the subsequent bacteria-bacteria interactions are the main driver of bacterial succession. Interestingly, the recolonization pattern on adult hosts resembles the ontogenetic colonization succession. This process occurs independently of the bacterial composition of the inoculum and can be followed at the level of individual bacteria. To identify potential metabolic traits associated with initial colonization success and potential metabolic interactions among bacteria associated with bacterial succession, we reconstructed the metabolic networks of bacterial colonizers based on their genomes. These analyses revealed that bacterial metabolic capabilities reflect the recolonization pattern, and the degradation of chitin might be a selection factor during early recolonization of the animal. Concurrently, transcriptomic analyses revealed that Nematostella possesses two chitin synthase genes, one of which is upregulated during early recolonization.

CONCLUSIONS

Our results show that early recolonization events are strongly controlled by the host while subsequent colonization depends on metabolic bacteria-bacteria interactions largely independent of host ontogeny. Video Abstract.

Lifestyle of sponge symbiont phages by host prediction and correlative microscopy

Bacteriophages (phages) are ubiquitous elements in nature, but their ecology and role in animals remains little understood. Sponges represent the oldest known extant animal-microbe symbiosis and are associated with dense and diverse microbial consortia. Here we investigate the tripartite interaction between phages, bacterial symbionts, and the sponge host. We combined imaging and bioinformatics to tackle important questions on who the phage hosts are and what the replication mode and spatial distribution within the animal is. This approach led to the discovery of distinct phage-microbe infection networks in sponge versus seawater microbiomes. A new correlative in situ imaging approach ('PhageFISH-CLEM') localised phages within bacterial symbiont cells, but also within phagocytotically active sponge cells. We postulate that the phagocytosis of free virions by sponge cells modulates phage-bacteria ratios and ultimately controls infection dynamics. Prediction of phage replication strategies indicated a distinct pattern, where lysogeny dominates the sponge microbiome, likely fostered by sponge host-mediated virion clearance, while lysis dominates in seawater. Collectively, this work provides new insights into phage ecology within sponges, highlighting the importance of tripartite animal-phage-bacterium interplay in holobiont functioning. We anticipate that our imaging approach will be instrumental to further understanding of viral distribution and cellular association in animal hosts.

The sponge holobiont in a changing ocean: from microbes to ecosystems

The recognition that all macroorganisms live in symbiotic association with microbial communities has opened up a new field in biology. Animals, plants, and algae are now considered holobionts, complex ecosystems consisting of the host, the microbiota, and the interactions among them. Accordingly, ecological concepts can be applied to understand the host-derived and microbial processes that govern the dynamics of the interactive networks within the holobiont. In marine systems, holobionts are further integrated into larger and more complex communities and ecosystems, a concept referred to as "nested ecosystems." In this review, we discuss the concept of holobionts as dynamic ecosystems that interact at multiple scales and respond to environmental change. We focus on the symbiosis of sponges with their microbial communities-a symbiosis that has resulted in one of the most diverse and complex holobionts in the marine environment. In recent years, the field of sponge microbiology has remarkably advanced in terms of curated databases, standardized protocols, and information on the functions of the microbiota. Like a Russian doll, these microbial processes are translated into sponge holobiont functions that impact the surrounding ecosystem. For example, the sponge-associated microbial metabolisms, fueled by the high filtering capacity of the sponge host, substantially affect the biogeochemical cycling of key nutrients like carbon, nitrogen, and phosphorous. Since sponge holobionts are increasingly threatened by anthropogenic stressors that jeopardize the stability of the holobiont ecosystem, we discuss the link between environmental perturbations, dysbiosis, and sponge diseases. Experimental studies suggest that the microbial community composition is tightly linked to holobiont health, but whether dysbiosis is a cause or a consequence of holobiont collapse remains unresolved. Moreover, the potential role of the microbiome in mediating the capacity for holobionts to acclimate and adapt to environmental change is unknown. Future studies should aim to identify the mechanisms underlying holobiont dynamics at multiple scales, from the microbiome to the ecosystem, and develop management strategies to preserve the key functions provided by the sponge holobiont in our present and future oceans.

Can we forget the Mini-Mental State Examination? A systematic review of the validity of cognitive screening instruments within one month after stroke

Objective:

To review systematically studies investigating the convergent, criterion, and predictive validity of multi-domain cognitive screening instruments in the first four weeks after stroke.

Data sources:

Electronic databases (Pubmed, PsycINFO, CINAHL, Embase) were searched until June 2014.

Review methods:

Studies concerning screening for cognitive dysfunction in stroke patients using multi-domain instruments, within four weeks postinfarct or haemorrhagic stroke, using tests taking no longer than one hour. Convergent, criterion, and predictive validity were examined.

Results:

A total of 51 studies investigating 16 cognitive screening instruments were identified. None of the instruments covered all of the most affected cognitive domains. Only one study investigated the convergent validity of a multi-domain test during the (sub)acute phase after stroke. A total of 15 studies examined the criterion validity of cognitive measurements during the acute phase after stroke. The Montreal Cognitive Assessment and Higher Cortical Function Deficit Test had good criterion validity. A total of 24 studies examined the predictive ability of multi-domain cognitive instruments applied in the acute phase after stroke. The Cognistat, Montreal Cognitive Assessment, and Functional Independence Measure-cognitive showed good predictive validity. The Mini-Mental State Examination is the most widely used cognitive screening instrument, but shows insufficient criterion validity.

Conclusion:

None of the existing instruments fulfils all criteria. The Montreal Cognitive Assessment is the best candidate at present, provided items measuring speed of information processing are added, and further studies investigating the optimal cut-offs are conducted.

16S rRNA gene-based identification of Elizabethkingia meningoseptica (Flavobacteriales: Flavobacteriaceae) as a dominant midgut bacterium of the Asian malaria vector Anopheles stephensi (Dipteria: Culicidae) with antimicrobial activities

Following their transmission from the human to the mosquito with the bloodmeal, malaria parasites have to persevere in the mosquito midgut for approximately 1 d. During this period the parasites are highly vulnerable to factors of the mosquito midgut, including bacteria. We here aimed at determining the microbial diversity of gut bacteria of the Asian malaria vector Anopheles stephensi (Liston) during development and under different feeding regimes, including feeds on malaria parasite-infected blood. 16S rRNA and denaturing gradient gel electrophoresis analyses demonstrated an increasing reduction in the microbial diversity during mosquito development from egg to adult and identified the gram-negative bacterium Elizabethkingia meningoseptica King as the dominant species in the midgut of lab-reared male and female mosquitoes. E. meningoseptica is transmitted between generations and its predominance in the mosquito midgut was not altered by diet, when the gut microbiota was compared between sugar-fed and blood-fed female mosquitoes. Furthermore, feeds on blood infected with malaria parasites did not impact the presence of E. meningoseptica in the gut. Extracts from cultured E. meningoseptica were active against gram-positive and negative bacteria and yeast and against the blood and gametocyte transmission stages of the malaria parasite Plasmodium falciparum Welch. The antimicrobial and antiplasmodial activities of E. meningoseptica may account for its dominance in the midgut of the malaria vector.

Sponge white patch disease affecting the Caribbean sponge Amphimedon compressa

We report on a novel sponge disease, hereafter termed 'sponge white patch' (SWP), affecting the Caribbean sponge species Amphimedon compressa. SWP is characterized by distinctive white patches of variable size that are found irregularly on the branches of diseased sponges. Nearly 20% of the population of A. compressa at Dry Rocks Reef, Florida, USA, showed symptoms of SWP at the time of investigation (November 2007-July 2010). Approximately 21% of the biomass of SWP individuals was bleached, as determined by volume displacement. Scanning electron microscopy analysis showed severe degradation of bleached tissues. Transmission electron microscopy of the same tissues revealed the presence of a spongin-boring bacterial morphotype that had previously been implicated in sponge disease (Webster et al. 2002; Mar Ecol Prog Ser 232:305-309). This particular morphotype was identified in 8 of 9 diseased A. compressa individuals investigated in this study. A close relative of the aforementioned disease-causing alphaproteobacterium was also isolated from bleached tissues of A. compressa. However, whether the spongin-boring bacteria are true pathogens or merely opportunistic colonizers remains to be investigated. Molecular fingerprinting by denaturing gradient gel electrophoresis (DGGE) demonstrated a distinct shift from the microbiota of healthy A. compressa to a heterogeneous mixture of environmental bacteria, including several phylotypes previously implicated in sponge stress or coral disease. Nevertheless, tissue transplantation experiments conducted in the field failed to demonstrate infectivity from diseased to healthy sponges, leaving the cause of SWP in A. compressa to be identified.

Nitrate Respiration in Chemoautotrophic Symbionts of the Bivalve Lucinoma aequizonata Is Not Regulated by Oxygen

The marine bivalve Lucinoma aequizonata has intracellular chemoautotrophic symbionts residing in the gill tissue. These bacteria are capable of nitrate respiration even under fully saturated oxygen conditions. Nitrate reductase in the symbionts of L. aequizonata appears to be constitutively expressed and without significant regulation by oxygen or nitrate. We discuss the stationary-phase growth state of the symbionts as an explanation for the lack of enzyme induction.

Sorbicillactone A: a structurally unprecedented bioactive novel-type alkaloid from a sponge-derived fungus

This chapter deals with the discovery of sorbicillactone A, as an illustrative example of the fruitful cooperation within BIOTECmarin--its isolation and chemical characterization, and its biological activities. Sorbicillactone A was isolated from a strain of Penicillium chrysogenum cultured from a sample of the Mediterranean sponge Ircinia fasciculata; it possesses a unique bicyclic lactone structure, seemingly derived from sorbicillin. Among the numerous known sorbicillin-derived structures, it is the first found to contain nitrogen and thus the first representative of a novel type of 'sorbicillin alkaloids', apparently originating from a likewise remarkable biosynthesis. Furthermore, the compound exhibits promising activities in several mammalian and viral test systems, in particular a highly selective cytostatic activity against murine leukemic lymphoblasts (L5178y) and the ability to protect human T cells against the cytopathic effects of HIV-1. These properties qualify sorbicillactone A or one of its derivatives for animal and (hopefully) also future therapeutic human trials.

Microbial diversity of marine sponges

The recent application of molecular microbial ecology tools to sponge-microbe associations has revealed a glimpse into the biodiversity of these microbial communities, that is considered just 'the tip of the iceberg'. This chapter provides an overview over these new findings with regard to identity, diversity and distribution patterns of sponge-associated microbial consortia. The sponges Aplysina aerophoba (Verongida), Rhopaloeides odorabile (Dicytoceratida) and Theonella swinhoei (Lithistida) were chosen as model systems for this review because they have been subject to both, cultivation-dependent and cultivation-independent approaches. A discussion of the microbial assemblages of Halichondriapanicea is presented in the accompanying chapter by Imhoff and Stöhr. Considering that a large fraction of sponge-associated microbes is not yet amenable to cultivation, an emphasis has been placed on the techniques centering around the 16S rRNA gene. A section has been included that covers the potential of sponge microbial communities for drug discovery. Finally, a 'sponge-microbe interaction model' is presented that summarizes our current understanding of the processes that might have shaped the community structure of the microbial assemblages within sponges.

On the problem of establishing the subcellular localization of Dictyostelium retrotransposon TRE5-A proteins by biochemical analysis of nuclear extracts

At first sight a protein that is enriched in extracts prepared from nuclei by means of biochemical methods can be considered to be a nuclear protein in vivo. Although this assumption will hold true for most of the analyzed proteins, it could also lead to false interpretations. We analyzed the subcellular distribution of endogenous and plasmid-borne proteins derived from the retrotransposon TRE5-A of Dictyostelium discoideum. In biochemical fractionation experiments the proteins encoded by TRE5-A open reading frame 1 (ORF1p) and the putative endonuclease encoded in ORF2 (ENp) were found in the detergent-insoluble material containing the nuclei. However, salt extraction of isolated nuclei did not considerably release the TRE5-A proteins. Instead, the TRE5-A proteins were strongly enriched in a fraction that contained the chromosomal DNA after removal of most cytoskeletal and histone proteins. These observations implied that ORF1p and ENp were both attached to chromatin in vivo, but this conclusion was disproved by the expression of genetic fusions of green fluorescent protein with either ORF1p or ENp. We show conclusive evidence that both fusion proteins were located as large aggregates of native protein in the cytoplasm of D. discoideum cells.

Pathogenicity islands: the tip of the iceberg

Pathogenicity islands represent distinct genetic elements encoding virulence factors of pathogenic bacteria. Pathogenicity islands belong to the class of genomic islands, which are common genetic elements sharing a set of unifying features. Genomic islands have been acquired by horizontal gene transfer. In recent years many different genomic islands have been discovered in a variety of pathogenic as well as non-pathogenic bacteria. Because they promote genetic variability, genomic islands play an important role in microbial evolution.

Isolation and phylogenetic analysis of bacteria with antimicrobial activities from the Mediterranean sponges Aplysina aerophoba and Aplysina cavernicola

The aim of this study was to isolate bacteria with antimicrobial activities from the marine sponges Aplysina aerophoba and Aplysina cavernicola. The obtained 27 isolates could be subdivided into eight phylogenetically different clusters based on comparative sequence analysis of their 16S rDNA genes. The sponge isolates were affiliated with the low (Bacillus) and high G+C Gram-positive bacteria (Arthobacter, Micrococcus), as well as the alpha-Proteobacteria (unknown isolate) and gamma-Proteobacteria (Vibrio, Pseudoalteromonas). One novel Bacillus species was identified and two species were closely related to previously uncharacterized strains. Isolates with antimicrobial activity were numerically most abundant in the genera Pseudoalteromonas and the alpha-Proteobacteria. The sponge isolates show antimicrobial activities against Gram-positive and Gram-negative reference strains but not against the fungus Candida albicans. A general pattern was observed in that Gram-positive bacteria inhibited Gram-positive strains while Gram-negative bacteria inhibited Gram-negative isolates. Antimicrobial activities were also found against clinical isolates, i.e. multi-resistant Staphylococcus aureus and Staphylococcus epidermidis strains isolated from hospital patients. The high recovery of strains with antimicrobial activity suggests that marine sponges represent an ecological niche which harbors a hitherto largely uncharacterized microbial diversity and, concomitantly, a yet untapped metabolic potential.

Fluorometric analysis of DNA unwinding (FADU) as a method for detecting repair-induced DNA strand breaks in UV-irradiated mammalian cells

Fluorometric analysis of DNA unwinding (FADU assay) was originally designed to detect X-ray-induced DNA damage in repair-proficient and repair-deficient mammalian cell lines. The method was modified and applied to detect DNA strand breaks in Chinese hamster ovary (CHO) cells exposed to ionizing radiation as well as to UV light. Exposed cells were allowed to repair damaged DNA by incubation for up to 1 h after exposure under standard growth conditions in the presence and in the absence of the DNA synthesis inhibitor aphidicolin. Thereafter, cell lysates were mixed with 0.15 M sodium hydroxide, and DNA unwinding took place at pH 12.1 for 30 min at 20 degrees C. The amount of DNA remaining double-stranded after alkaline reaction was detected by binding to the Hoechst 33258 dye (bisbenzimide) and measuring the fluorescence. After exposure to X-rays DNA strand breaks were observed in all cell lines immediately after exposure with subsequent restitution of high molecular weight DNA during postexposure incubation. In contrast, after UV exposure delayed production of DNA strand break was observed only in cell lines proficient for nucleotide excision repair of DNA photoproducts. Here strand break production was enhanced when the polymerization step was inhibited by adding the repair inhibitor aphidicolin during repair incubation. These results demonstrate that the FADU approach is suitable to distinguish between different DNA lesions (strand breaks versus base alterations) preferentially induced by different environmental radiations (X-rays versus UV) and to distinguish between the different biochemical processes during damage repair (incision versus polymerization and ligation).

Common molecular mechanisms of symbiosis and pathogenesis

Traditionally, symbiotic and pathogenic interactions were considered different manifestations of the bacteria-host interaction. However, the molecular mechanisms that mediate communication between and cellular modulation of the involved partners are quite similar. With this review we aim to contribute to a reduction of the traditional gap between symbiosis and pathogenesis research.

Symbiosis and pathogenesis: evolution of the microbe-host interaction

Symbiotic and pathogenic bacteria have in common that they live in or on host organisms or host cells. To make a successful living in eukaryotic hosts, bacteria must possess the traits to recognize a given host and establish adherence. When the bacterial location is internal or intracellular, they must further have the ability to invade, to establish a niche, and finally to multiply within a host. The underlying mechanisms which allow this form of existence show similarities between symbiotic and pathogenic bacteria. The final outcome, however, may result in a wide spectrum of consequences for the host ranging from the acquisition of novel metabolic pathways to damage or death. Despite the vastly different forms of interactions, symbiotic and pathogenic bacteria have in common that they are adapted to a particular environmental niche represented by the host organism or compartment thereof. This contribution reviews the evolutionary forces which have shaped the microbial-host interactions. Particular emphasis is placed on the genetic and molecular mechanisms that drive bacterial evolution in response to the selective pressures of the host environment.

Emotional stability and facial activity as predictors for pain tolerance

40 subjects were given the Cold Pressor Test. There were large individual differences in the time subjects were willing to keep their hands immersed in the cold water. Predictors indicated for these differences were sex, emotional stability, and facial activity during the test. Emotional stability was measured by means of questionnaire scales and facial activity by ratings on the basis of videotapes.

Coordinate intracellular expression of Salmonella genes induced during infection

Salmonella typhimurium in vivo-induced (ivi) genes were grouped by their coordinate behavior in response to a wide variety of environmental and genetic signals, including pH, Mg2+, Fe2+, and PhoPQ. All of the seven ivi fusions that are induced by both low pH and low Mg2+ (e.g., iviVI-A) are activated by the PhoPQ regulatory system. Iron-responsive ivi fusions include those induced under iron limitation (e.g., entF) as well as one induced by iron excess but only in the absence of PhoP (pdu). Intracellular expression studies showed that each of the pH- and Mg2+-responsive fusions is induced upon entry into and growth within three distinct mammalian cell lines: RAW 264.7 murine macrophages and two cultured human epithelial cell lines: HEp-2 and Henle-407. Each ivi fusion has a characteristic level of induction consistent within all three cell types, suggesting that this class of coordinately expressed ivi genes responds to general intracellular signals that are present both in initial and in progressive stages of infection and may reflect their responses to similar vacuolar microenvironments in these cell types. Investigation of ivi expression patterns reveals not only the inherent versatility of pathogens to express a given gene(s) at various host sites but also the ability to modify their expression within the context of different animal hosts, tissues, cell types, or subcellular compartments.

[Psychodynamic personality markers of psychotherapists in relation to therapy outcome]

In the Berlin psychotherapy study data were collected not only from the patients but also from the therapists. Thus, the influence of personality variables of the therapists on the multidimensionally registered therapy success could be studied. To this end a nonlinear k-sets canonical analysis was applied resulting in a sample-specific optimal scaling. The relationship pattern of the two sets of variables found was satisfactory as regards the internal criteria of the programme as well as its clinical meaningfulness. The results can be used in similar studies for specifying therapist-related hypotheses.

Therapeutic alliance and transference: an exploratory study of their empirical relationship

Transference and the formation of a therapeutic alliance were studied in 126 patients from the Berlin psychotherapy project. The working hypothesis was that the internalized mother and father image would have an influence on the therapeutic alliance. The therapist rated the development of the therapeutic alliance at two points in time. When the parents' images and the therapist image were compared by using difference and similarity measures, four mother and four father types could be constructed of which some showed significant differences in the formation of therapeutic alliance. The introduction and the discussion are focused on the question as to what extent the psychoanalytic assumptions of transference can be useful in empirical therapy research for the construction of new variables and the explanation of social interactions between the two partners.

Bacterial infection as assessed by in vivo gene expression

In vivo expression technology (IVET) has been used to identify > 100 Salmonella typhimurium genes that are specifically expressed during infection of BALB/c mice and/or murine cultured macrophages. Induction of these genes is shown to be required for survival in the animal under conditions of the IVET selection. One class of in vivo induced (ivi) genes, iviVI-A and iviVI-B, constitute an operon that resides in a region of the Salmonella genome with low G+C content and presumably has been acquired by horizontal transfer. These ivi genes encode predicted proteins that are similar to adhesins and invasins from prokaryotic and eukaryotic pathogens (Escherichia coli [tia], Plasmodium falciparum [PfEMP1]) and have coopted the PhoPQ regulatory circuitry of Salmonella virulence genes. Examination of the in vivo induction profile indicates (i) many ivi genes encode regulatory functions (e.g., phoPQ and pmrAB) that serve to enhance the sensitivity and amplitude of virulence gene expression (e.g., spvB); (ii) the biochemical function of many metabolic genes may not represent their sole contribution to virulence; (iii) the host ecology can be inferred from the biochemical functions of ivi genes; and (iv) nutrient limitation plays a dual signaling role in pathogenesis: to induce metabolic functions that complement host nutritional deficiencies and to induce virulence functions required for immediate survival and spread to subsequent host sites.

The contribution of nitrate respiration to the energy budget of the symbiont-containing clam Lucinoma aequizonata: a calorimetric study

Heat production and nitrate respiration rates were measured simultaneously in the gill tissue of Lucinoma aequizonata. This marine bivalve contains chemoautotrophic, intracellular, bacterial symbionts in its gill tissue. The symbionts show constitutive anaerobic respiration, using nitrate instead of oxygen as a terminal electron acceptor. An immediate increase in heat production was observed after the addition of nitrate to the perfusion medium of the calorimeter and this was accompanied by the appearance of nitrite in the effluent sea water. The nitrate-stimulated heat output was similar under aerobic and anaerobic conditions, which is consistent with the constitutive nature of nitrate respiration. The amount of heat released was dependent on the concentration of nitrate in the perfusion medium. At nitrate concentrations between 0.5 and 5 mmol l-1, the total heat production was increased over twofold relative to unstimulated baseline values. A mean (±s.e.m.) experimental enthalpy of -130±22.6 kJ mol-1 nitrite (N=13) was measured for this concentration range.

Defensive and affective-emotional reactions to war: the Abkhazian war as reflected in people's subjective reactions

Differences in defensive and affective-emotional reactions of 108 male Georgian subjects who had been confronted with the consequences of the Abkhazian war in different ways (nonwounded soldiers, wounded soldiers, and civilian controls) were significant between groups on all defense scales and four of the 12 Gottschalk-Gleser scales. The results are discussed from a perspective with war forming for all three groups an important life event which differentially determined their psychological reactions.

Basic cultural values and differences in attitudes towards health, illness and treatment preferences within a psychosomatic frame of reference

BACKGROUND

Regarded from a biopsychosocial point of view, a culturally determined differential impact of values, lifestyles and attitudes can be expected on health and illness concepts, exerting a potential influence on the general satisfaction with the health care system as well as on subjective treatment preferences.

METHODS

57 men and 63 women between 16 and 86 years of age in the Netherlands and 45 men and 39 women aged between 15 and 78 years in Japan took part in the study. Questions to the subjects were not exclusively restricted to medical care but comprised the potential relationship between health and illness on the one hand, and lifestyles, values, attitudes and treatment preferences on the other. On the basis of previous experience with data from the Dutch sample 27 questions were selected and, using the whole sample, submitted to a factor analysis. Furthermore subjective health and illness attributions were compared by means of a projective technique.

RESULTS

The factor analysis resulted in five dimensions: relaxation, work, hedonistic goals versus social status, family life versus career making, alternative versus conventional medical care, with three significant differences between the two countries and two significant gender effects. The projective technique revealed two cultural differences in illness attributions.

CONCLUSIONS

The implications of these results for possible health promotion campaigns and a differential choice of health-care strategies are discussed from within a psychosomatic frame of reference. It is hypothesized that the revealed differences can also be useful for attempts at a group-specific increase of acceptance and compliance of certain treatments.

Stress-related psychophysiological reactions of truck drivers in relation to anxiety, defense, and situational factors

A system analytic frame of reference is chosen for analysing interindividual differences in driving a technically optimised tank-lorry in comparison to a standard tank-lorry. Seven professional tank-lorry drivers were tested with psychological tests, and their test results were related to physiological measures assessed under different driving conditions in both lorry types. Two dimensions were used to explain the pattern of interactions between the independent (psychological and situational) and dependent (physiological) variables. It is argued that beyond technical improvements, also taking into account information on personality variables and situational factors is a promising approach to accident prevention research.

The Defense Mechanism Test in clinical and personality research

Different research strategies are used for the application of the Defense Mechanism Test in clinical and personality research. It is argued that the harvest of useful information would be greater if the effort of different research groups could be coordinated.

Prediction of endocrine stress reactions by means of personality variables

The study examined the predictability of endocrine stress indicators on the basis of personality measures. The subjects were 83 computer operators (63 men, 20 women; mean age 28 years) who by means of an experimental situation were confronted with a mild stressor (a cognitive two-channel task with a high information load). Using scores on personality questionnaires (comprising scales for defense mechanisms, neuroticism, and 2 achievement motivation variables), subjects were classified into extreme groups of stress-resistant (17 subjects) versus nonstress-resistant (13 subjects). Immediately after the experiment blood samples were taken to assay the norepinephrine metabolites plasma-free 3-methoxy-4-hydroxy-phenylglycol (MHPG) and MHPG sulfate (MHPG.SO4), which formed the dependent variables. Personality measures and endocrine stress indicators were until the final analysis of the data kept apart by a double-blind strategy. A significant difference was noted in the MHPG level between the stress-resistant and the nonstress-resistant group. The value and applicability of these results for stress prevention is discussed.

Moderating effects of trait anxiety on electrodermal reactions in different learning conditions

This study examined the control of the effects of trait anxiety on GSR during a problem-solving task under different conditions. Of 84 subjects, 39 men and 49 women of mean age 21 yr., 42 were classified as high in anxiety, 42 as low in anxiety. Subjects solved concept-formation tasks at different degrees of difficulty under one of three learning conditions. Low tone, unpleasant loud tone, and unpleasant electric shock provided the three kinds of error feedback. For the ‘low tone’ and ‘electric shock’ as feedback on errors significant differences in GSR values resulted for groups high and low in anxiety with the latter showing higher scores. The relevance of physiological patterns in multidimensional activation theories for research on anxiety is discussed.

[The patient and his psychotherapist: an analog study on the choice of therapy and reflections on the significance of person perception in psychotherapy]

In order to analyse the first beginning of therapeutic interaction an analog study was performed considering especially the social psychological elements of the situation. 93 subjects (mainly students of psychology and medicine, 54 female and 39 male, 18-30 years old) were shown two parts of films presenting examples for non-directive and behaviour therapy and then had to make a decision which therapy they would choose if they had psychologically determined problems. According to the demonstration in the film it was hypothesized that the arguments for choosing a therapy would be related more to the technique but instead most of the arguments were concerned with the person of the therapist. The influence of person-perception and halo-effects could also be shown by comparing the two therapist and other relevant roles including the self-description of the subjects by means of grid-technique with a pre-formed list of adjectives. Regarding other hypothetical influences of the required choice, also a set of personality variables gave a significant discrimination for the two therapy preference groups. The meaning and influence of person perception for the whole therapy process is taken up in the discussion. It is argued that person-perception might have greater influence in earlier phases of therapy, but is then succeeded by an interaction of learning strategies required by the therapist and the learning capacity of the patient.

[The current state of cutaneous tuberculosis]

Thirty-three years after the introduction of the chemotherapeutics and as result of massive prophylactic and preventive measures the tuberculosis of the skin shows a clear epidemiologic and clinical change. Nowadays the clinical picture of the tuberculosis of the skin restricts essentially to the classical forms of the lupous, verrucous and colliquative tubervulosis of the skin, the specific etiology and pathogenesis of which are ascertained. The so-called tuberculids should at present only be treated in a qualified sense in the chapter of tuberculosis of the skin. After a short description of the diagnostic possibilities and after a historical survey on former measures of treatment the present GDR standard in therapy is explained. The qualification for carrying on the isonicotinic acid hydrazide monotherapy in the tuberculosis cutis luposa and verrucosa is proved on the basis of bacteriological, pathologo-anatomical and clinical peculiarities of these forms of tuberculosis of the skin.

[Attempts at a nosological classification with two standardized psychiatric rating scales (author's transl)]

Three different procedures for classification of psychiatric patients, a modified form of Q factor analysis, the classical discriminant analysis and a simple procedure based on clinical concepts, were compared empirically. On the basis of the psychopathological state rated by means of the Inpatient Multidimensional Psychiatric Scale (IMPS) and psychopathological and somatic scales of the AMP documentation system (AMP scale), the three procedures were applied in order to reproduce the psychiatric diagnosis. The classification was made by paired comparison of the following four diagnoses: schizophrenia, paranoid form (n = 45), schizophrenia, unspecified form (n = 47), depressive psychosis (n = 44), and depressive neurosis (n = 53). The procedures were evaluated according to their crossvalidation results. The mean percentages of correct classification were the following: 83% for the modified form of Q factor analysis, 77% for the classical discriminant analysis, 73% for the simple procedure based on clinical concepts using the IMPS, and 79% for the same procedure, but using the AMP scale, all three procedures reaching about the same level of validity.

[Psychiatric classification by means of a discriminatory application of Q factor analysis (author's transl)]

An attempt is made to separate different pairs of psychiatric patient groups by means of a modified form of Q factor analysis comparable to discriminant analysis. The psychopathological state of 454 patients had been rated using two psychiatric rating scales, the IMPS (Inpatient Multidimensional Psychiatric Scale) by Lorr et al. and the psychopathological and somatic scales of the AMP documentation system. Out of these patients the four most frequently occurring groups (schizophrenia, paranoid form, n = 45; schizophrenia, unspecified form, n = 47; depressive psychosis, n = 44; depressive neurosis, n = 53) were selected. Each patient group was divided randomly into two samples, an analysis sample and a validation sample. Only those items were selected which discriminated best between any two analysis samples. Using G indices a Q factor analysis was calculated, and the results improved by a criterion-related additional rotation. The resulting weights were transferred to the validation samples in order to have a cross validation. The mean percentage of correct placements within the validation samples was 83%.