[Social psychiatry and neurobiology : A long overdue convergence exemplified by schizophrenia]

BACKGROUND

The proliferation of biological psychiatry has greatly increased over the last two decades. With the possibility to carry out brain research using modern technical methods, it seemed that social influencing factors would lose importance in the development of mental diseases; however, in actual fact this does not seem to be justified. It is necessary to overcome this separation, in that social factors are incorporated into a conceptual framework in the development of mental diseases, which simultaneously also takes the results of current neurobiological research into consideration.

OBJECTIVES AND METHODS

The aims of this review article are to summarize the current state of sociopsychiatric research and to emphasize the perspectives of the biological principles and their validity with respect to the social dimensions of psychiatry, as exemplified by schizophrenic disorders. The article presents the options for a biosocial approach in social psychiatry and gives an overview of the currently available literature.

RESULTS AND CONCLUSION

There is an abundance of neurobiological research approaches, which are closely associated with sociopsychiatric topics, such as social cognition. Social psychiatry and biological psychiatry should no longer be considered as diametrically opposed subdisciplines. On the contrary, the options which could emerge from a synthesis must be used in research and clinical practice.

Relationship between personality and psychopathology in a longitudinal community study: a test of the predisposition model

BACKGROUND

Mounting evidence supports the notion that personality is crucial in the aetiopathology of common mental disorders, but studies that allow for aetiological conclusions are lacking. The aim of the present study was thus to provide a test of the predisposition model.

METHOD

We analysed data from the Zurich Cohort Study, a 30-year longitudinal epidemiological community study of an adult cohort (n = 591) from 1979 to 2008. Personality was assessed in 1988 with an established personality questionnaire, and psychopathology through seven semi-structured interviews between 1979 and 2008.

RESULTS

On the basis of personality assessment from 1988, used as predictor of subsequent psychopathology (1993-2008), while adjusting for sex and prior mental disorders (1979-1988), neuroticism related significantly with future major depression episodes [odds ratio (OR) = 1.41], anxiety disorders (OR = 1.32) and depression treatment use (OR = 1.41). When participants with a past 10-year history (i.e. 1979-1988) of either major depression, anxiety disorder or depression treatment use were excluded, neuroticism in 1988 still significantly predicted first incidence (i.e. 1993-2008) of major depression episodes (OR = 1.53) and depression treatment use (OR = 1.84).

CONCLUSIONS

The present study provides compelling evidence that the personality trait of neuroticism constitutes an independent risk factor for subsequent major depression episodes and use of respective professional treatments, which serves as a proxy for particularly severe and impairing depression episodes. We therefore advocate that personality traits could provide clinically useful prognostic information when considered carefully.

Trimodal approach (PET/MR/EEG) of response inhibition as a possible biomarker for schizophrenia

Introduction

The aim of the FP7-European funded project TRIMAGE is to create a trimodal, cost-effective imaging tool consisting of PET/MR/EEG to enable effective early diagnosis of schizophrenia.

Objective

In the scope of this project we are interested in the multimodal assessment of response inhibition. The loudness dependence of auditory evoked potential (LDAEP) is a suitable biomarker of inhibitory action in signal processing. Variations in response inhibition can have great impact on different aspects of life. Individuals with reduced capability of inhibitory control have a tendency to impulsive behavior. Studies showed that they have stronger LDAEP values. Patients with schizophrenia may exhibit alterations in the responsiveness to sensory stimuli. Thus, a reduced LDAEP was found in these patients. However, these deviances differed in clinical features of the disorder. Therefore, we would like to further elucidate the relationship between multimodal neuroimaging methods and dimensions of symptoms, observable behavior, personality traits and general psychopathological dysfunction.

Methods

A sample of 20 healthy controls and 20 patients with manifest schizophrenia will be examined with the LDAEP paradigm in a trimodal approach with customary imaging tools. PET measurements with the radiotracer [11C]-flumazenil will be used to assess the binding potentials of GABA-A receptors. MRS will provide data about GABA concentrations. Simultaneously recorded EEG-fMRI data will permit new insight in the relationship between LDAEP and impulsivity.

Discussion

The project will use alternative approaches to psychiatric classification. Response inhibition in sensory processing will be investigated from different angles (biochemical, neurophysiological, and neuroanatomical) and combined with psychological characteristic values.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Changes in neurocognitive functioning during transition to manifest disease: comparison of individuals at risk for schizophrenic and bipolar affective psychoses

BACKGROUND

Neurocognitive deficits are important aspects of schizophrenic disorder because they have a strong impact on social and vocational outcomes. Previously it was assumed that cognitive abilities progressively deteriorate with illness onset. However, recent research results have contradicted this with observations of continuous or even improved performance in individuals at risk for psychosis or manifest schizophrenia. The objective of our longitudinal study was to examine neurocognitive functioning in help-seeking individuals meeting basic symptoms or ultra-high-risk criteria for schizophrenic psychosis (HRSchiz) or risk criteria for affective psychosis (HRBip). The progression of cognitive functioning in individuals converting to psychosis was compared with that of at-risk individuals who did not convert during the follow-up period.

METHOD

Data were available from 86 study participants who completed neurocognitive and clinical assessments at baseline and, on average, 12.8 (s.d. = 1.5) months later. Neurocognitive measures were grouped according to their load in factor analysis to five cognitive domains: speed, attention, fluency, learning and memory, and working memory.

RESULTS

Neurocognitive functioning in HRSchiz and HRBip individuals generally improved over time. Subjects converting to manifest psychosis displayed a stable neurocognitive profile from baseline to follow-up. Compared with non-converters, they had already demonstrated a significantly lower level of performance during their baseline examinations.

CONCLUSIONS

Our data provide no evidence for a progressive cognitive decline in individuals at risk of psychosis. In line with the neurodevelopmental model, our findings suggest that cognitive deficits are already present very early, before or during the prodromal stage of the illness.

Neurocognitive profiles in help-seeking individuals: comparison of risk for psychosis and bipolar disorder criteria

BACKGROUND

Neurocognitive deficits are important aspects of the schizophrenic disorders because they have a strong impact on social and vocational outcomes. We expanded on previous research by focusing on the neurocognitive profiles of persons at high risk (HR) or ultra-high risk (UHR) for schizophrenic and affective psychoses. Our main aim was to determine whether neurocognitive measures are sufficiently sensitive to predict a group affiliation based on deficits in functional domains.

METHOD

This study included 207 help-seeking individuals identified as HR (n = 75), UHR (n = 102) or at high risk for bipolar disorder (HRBip; n = 30), who were compared with persons comprising a matched, healthy control group (CG; n = 50). Neuropsychological variables were sorted according to their load in a factor analysis and were compared among groups. In addition, the likelihood of group membership was estimated using logistic regression analyses.

RESULTS

The performance of HR and HRBip participants was comparable, and intermediate between the controls and UHR. The domain of processing speed was most sensitive in discriminating HR and UHR [odds ratio (OR) 0.48, 95% confidence interval (CI) 0.28-0.78, p = 0.004] whereas learning and memory deficits predicted a conversion to schizophrenic psychosis (OR 0.47, 95% CI 0.25-0.87, p = 0.01).

CONCLUSIONS

Performances on neurocognitive tests differed among our three at-risk groups and may therefore be useful in predicting psychosis. Overall, cognition had a profound effect on the extent of general functioning and satisfaction with life for subjects at risk of psychosis. Thus, this factor should become a treatment target in itself.

Fatty acids synthesized by oral treponemes in chemically defined media

OMIZ-W68, a chemically defined medium that contains no long-chain fatty acids and yet supports in vitro proliferation of a wide range of fastidious oral anaerobes, is described. The type strains of Treponema denticola, Treponema lecithinolyticum, Treponema maltophilum, Treponema pectinovorum, Treponema socranskii, and an as yet unpublished canine Treponema species could be propagated indefinitely in this medium with sugar supplements for the saccharolytic species. Analysis of the cellular fatty acids (CFA) of these treponemes by gas chromatography demonstrated the synthesis of C14, C15, C16, and C17 fatty acids (linear-, iso-, and anteiso-forms) in various proportions, but neither hydroxy- nor unsaturated fatty acids. However, between 0% and 40% of the eluted material could not be identified. The proportions of CFAs differed not only between species but also between the eight strains of Treponema denticola investigated. Replacing OMIZ-W68 by a derivative minimal essential medium (OMIZ-M/TDCDK) developed for Treponema denticola had little effect on the CFA profiles. In contrast, the CFA profiles of treponemes grown in OMIZ-W68 showed at best minor similarity to the strains from the Moore library of the Virginia Polytechnic Institute, which had been grown in media containing serum, peptones, and yeast extract.

Guggenheimella bovis gen. nov., sp. nov., isolated from lesions of bovine dermatitis digitalis

Dermatitis digitalis is an economically important ulcerative disease of undetermined aetiology affecting the hooves of cattle. Material was examined from two independent cases of this disease in Switzerland. Cultures from the advancing front of both lesions yielded large numbers of closely related short, mesophilic, non-motile, non-spore-forming, anaerobic, proteolytic, Gram-positive rods. The 16S rRNA gene sequences of strains OMZ 913(T) and OMZ 915 were identical and indicate Tindallia magadiensis and Eubacterium saphenum as their closest relatives. Phenotypically, the novel isolates are clearly distinguished from related bacteria by protein and antigen patterns, by cellular fatty acids and by API ZYM activities. The diamino acid of the Gram-positive cell wall is ornithine and the G+C content of OMZ 913(T) DNA is 44.4 mol%. The phylogenetic distance from recognized taxa in the phylum Firmicutes is sufficient to place these bovine isolates into a novel genus and species, for which the name Guggenheimella bovis gen. nov., sp. nov. is proposed, with OMZ 913(T) (=CIP 108087(T)=DSM 15657(T)) as the type strain.

Treponema putidum sp. nov., a medium-sized proteolytic spirochaete isolated from lesions of human periodontitis and acute necrotizing ulcerative gingivitis

So far, little phenotypic heterogeneity has been detected in cultured oral treponemes with trypsin-like proteolytic activity, and all have been assigned to the species Treponema denticola. However, comparisons of protein patterns and antigen expression in our collection of proteolytic oral treponemes occasionally identified isolates with a unique phenotype; e.g. strain OMZ 830 (=ATCC 700768), which qualified as a ‘pathogen-related oral spirochaete’ due to the presence of a ∼37 kDa protein reactive with the Treponema pallidum FlaA-specific mAb H9-2. In addition to such single isolates, a homogeneous group of seven independent strains is described that were highly motile, medium-sized, proteolytic but asaccharolytic spirochaetes and were cultured from human gingivitis, periodontitis and acute necrotizing ulcerative gingivitis in medium OMIZ-Pat supplemented with 1 % human serum and antibiotics. Growth of these spirochaetes in OMIZ-Pat was not dependent on, but was stimulated by, human or bovine serum. Carbohydrates were neither required nor stimulatory for growth. The protein and antigen patterns of total cell extracts of these organisms separated by SDS-PAGE were distinct from those of all previously cultured spirochaetes, with highest similarity to T. denticola. The novel spirochaete has a 2 : 4 : 2 arrangement of the periplasmic flagella, similar to T. denticola. However, the flagellin pattern as detected by immunostaining or glycan staining of Western blots readily distinguished the novel group from T. denticola. Also, distinct from reference strains of T. denticola, none of the novel isolates displayed sialidase or dentilisin activities, both of which are expressed by most strains of T. denticola. Trypsin-like activity and other enzymes as detected by API ZYM test were similar to those of T. denticola. The status of a novel species is supported by the 16S rRNA gene sequence, with 98·5 % similarity to its closest cultured relative, T. denticola. The name Treponema putidum sp. nov. is proposed (type strain OMZ 758T=ATCC 700334T=CIP 108088T).

Selenium-dependent growth of Treponema denticola: evidence for a clostridial-type glycine reductase

Assessment of the nutritional requirements of Treponema denticola disclosed a strict growth dependence on selenium. In vivo labeling of cells of this organism with (75)Se and electrophoretic analysis revealed three labeled bands, two of which were selenoproteins correlating in size with subunits A and B of glycine reductase. Antibodies directed against glycine- or betaine-reductase subunits of Eubacterium acidaminophilum specifically also reacted with proteins from cell lysates of T. denticola. Moreover, ORFs within the T. denticola genome sequence were found whose products display high sequence similarity to glycine-reductase subunits. These findings strongly support the notion that T. denticola ferments amino acids via the activity of glycine reductase, an enzyme previously thought to be restricted to gram-positive bacteria.

Treponema parvum sp. nov., a small, glucoronic or galacturonic acid-dependent oral spirochaete from lesions of human periodontitis and acute necrotizing ulcerative gingivitis

Small oral spirochaetes with a strict dependence on either glucuronic acid (GluA) or galacturonic acid (GalA) were isolated from European patients with periodontitis and from Chinese patients with either gingivitis or acute necrotizing ulcerative gingivitis (ANUG). Thirteen such isolates were similar phenotypically to Treponema pectinovorum ATCC 33768T and this classification was confirmed by 16S rRNA sequencing. However, four isolates differed from T. pectinovorum by their small cell size, by a prominent beta-glucuronidase activity, by a distinct protein and antigen profile, by an inability to grow on pectin as sole source of carbohydrate and by a markedly enhanced growth rate when supplied with a second carbohydrate (L-arabinose, D-galactose, D-glucose, D-fructose, D-mannitol, D-mannose, pectin, D-ribose or D-xylose) in addition to the essential GluA/GalA. By 16S rRNA sequencing these four isolates clustered in the recently described phylotype 'Smibert-2'. T. pectinovorum (14 strains) and 'Smibert-2' (four isolates with beta-glucuronidase activity) could each be subdivided into two serotypes based on immunoblot reactivity with two mAbs. Representatives of the two groups, including T. pectinovorum ATCC 33768T, showed a 1:2:1-type periplasmic flagellar arrangement. 'Smibert-2' is described as a novel species, Treponema parvum sp. nov., with isolate OMZ 833T (= ATCC 700770T) proposed as the type strain and OMZ 842 (= ATCC 700773) as reference strain for a second serotype.

Tetrahydrobiopterin increases myocardial blood flow in healthy volunteers: a double-blind, placebo-controlled study

OBJECTIVES

Tetrahydrobiopterin (BH4) is a regulatory cofactor for the activity of nitric oxide synthases. Vasodilating properties of BH4 have been reported in vitro and in vivo. The influence of BH4 on myocardial blood flow (MBF), however, is largely unknown. We therefore performed a double-blind, placebo-controlled study to investigate the effect of intravenous BH4 on MBF in healthy volunteers.

METHODS AND RESULTS

Resting MBF was assessed in 15 subjects receiving either intravenous BH4 (10 mg/kg) or placebo using positron emission tomography (PET) and [13N]ammonia. From a mean baseline MBF of 0.91 +/- 0.09 ml/min/g, MBF increased to 1.18 +/- 0.10 ml/min/g after BH4 (n = 10; p = 0.0042). In contrast, in the group receiving placebo mean MBF remained unchanged (non-significant decrease from 0.97 +/- 0.19 to 0.84 +/- 0.11 ml/min/g; n = 5; p = 0.36). Systemic haemodynamics and ECGs remained unaffected in both groups. BH4 was very well tolerated.

CONCLUSION

Systemically administered BH4 is safe and effectively increases resting MBF in healthy volunteers.

Tetrahydrobiopterin increases myocardial blood flow in healthy volunteers: a double-blind, placebo-controlled study

OBJECTIVES

Tetrahydrobiopterin (BH4) is a regulatory cofactor for the activity of nitric oxide synthases. Vasodilating properties of BH4 have been reported in vitro and in vivo. The influence of BH4 on myocardial blood flow (MBF), however, is largely unknown. We therefore performed a double-blind, placebo-controlled study to investigate the effect of intravenous BH4 on MBF in healthy volunteers.

METHODS AND RESULTS

Resting MBF was assessed in 15 subjects receiving either intravenous BH4 (10 mg/kg) or placebo using positron emission tomography (PET) and [13N]ammonia. From a mean baseline MBF of 0.91 +/- 0.09 ml/min/g, MBF increased to 1.18 +/- 0.10 ml/min/g after BH4 (n = 10; p = 0.0042). In contrast, in the group receiving placebo mean MBF remained unchanged (non-significant decrease from 0.97 +/- 0.19 to 0.84 +/- 0.11 ml/min/g; n = 5; p = 0.36). Systemic haemodynamics and ECGs remained unaffected in both groups. BH4 was very well tolerated.

CONCLUSION

Systemically administered BH4 is safe and effectively increases resting MBF in healthy volunteers.

Treponema lecithinolyticum sp. nov., a small saccharolytic spirochaete with phospholipase A and C activities associated with periodontal diseases

Strong phospholipase A (PLA) and phospholipase C (PLC) activities as potential virulence factors are the outstanding characteristics of eight strains of small oral spirochaetes isolated from deep periodontal lesions. By qualitative dot-blot DNA-DNA hybridization and 16S rDNA sequence comparison, these spirochaetes form a distinct phylogenetic group, with Treponema maltophilum as its closest cultivable relative. Growth of these treponemes, cells of which contain two endoflagella, one at each pole, was autoinhibited by the PLA-mediated production of lysolecithin unless medium OMIZ-Pat was prepared without lecithin. N-Acetylglucosamine was essential and D-ribose was stimulatory for growth. All isolates were growth-inhibited when 1% foetal calf serum was added to the medium. Growth on agar plates supplemented with human erythrocytes produced haemolysis. In addition to PLA and PLC, the new isolates displayed strong activities of alkaline and acid phosphatases, beta-galactosidase, beta-glucuronidase, N-acetyl-beta-glucosaminidase and sialidase, intermediate activities of C4- and C8-esterases, naphthol phosphohydrolase and alpha-fucosidase and a distinctive 30 kDa antigen detectable on Western blots. This phenotypically and genotypically homogeneous group is proposed as a novel species, Treponema lecithinolyticum sp. nov., with isolate OMZ 684T designated as the type strain. A molecular epidemiological analysis using a T. lecithinolyticum-specific probe showed this organism to be associated with affected sites when compared with unaffected sites of periodontitis patients. This association was more pronounced in patients with rapidly progressive periodontitis than in those with adult periodontitis.

Flagellins, but not endoflagellar sheath proteins, of Treponema pallidum and of pathogen-related oral spirochetes are glycosylated

Glycosylation of the flagellar core proteins (FlaBs) was detected in Treponema pallidum Nichols and in the type or reference strains of seven oral Treponema species. In several nonmotile strains of oral treponemes, the FlaBs were undetectable by both antibody and glycan staining. In contrast, a spontaneous low-motility variant of T. vincenti poundi-related strain RitzA, OMZ 305A, lacked the flagellar sheath protein (FlaA) and the two glycan-staining FlaB bands of the wild type, but antibody labeling revealed a novel FlaB band with a lower relative molecular weight. A ca. 38-kDa component of isolated endoflagella of T. vincentii OMZ 800 was identified on Western blots as FlaA by monoclonal antibody (MAb) H9-2, which specifically labels the 37-kDa FlaA protein of T. pallidum. Glycan and H9-2 labeling patterns similar to those of T. pallidum were observed in whole-cell extracts of T. medium G7201 and of 10 strains classified as T. vincentii and as two T. vincentii-related taxons. These four groups were thus identified as cultivable pathogen (T. pallidum)-related oral spirochetes as defined by labeling with MAb H9-2. No H9-2 MAb-reactive component could be detected in T. amylovorum, T. denticola, T. maltophilum, T. pectinovorum, and the three subspecies of T. socranskii.

Treponema amylovorum sp. nov., a saccharolytic spirochete of medium size isolated from an advanced human periodontal lesion

A highly motile, medium-size, saccharolytic spirochete was isolated from an advanced human periodontal lesion in medium OMIZ-Pat supplemented with 1% human serum. The growth of this organism is dependent on either glucose, maltose, starch, or glycogen. The cells contain six endoflagella, three per pole, which overlap in the central region of the cell body. On the basis of its cell morphology and enzyme activities, as well as its sodium dodecyl sulfate-polyacrylamide gel electrophoresis protein and antigen profiles, this organism is clearly distinct from all previously cultured spirochetes. The presence of a novel species is supported by the 16S rRNA sequence of this organism, which places it in phylotype 19 of Choi et al. (B. K. Choi, B. J. Paster, F. E. Dewhirst, and U. B. Göbel, Infect. Immun. 62:1889-1895, 1994). The only isolate, strain HA2P, is designated the type strain of a novel species, for which we propose the name Treponema amylovorum.

Phylogenetic analysis of pathogen-related oral spirochetes

Recently, Riviere et al. reported as yet uncultivable invasive oral spirochetes that cross-reacted with monoclonal antibodies (MAbs) specific for Treponema pallidum (G. R. Riviere, K. S. Elliot, D. F. Adams, L. G. Simonson, L. B. Forgas, A. M. Nilius, and S. A. Lukehart, J. Periodontol. 63:131-136, 1992; G. R. Riviere, M. A. Wagoner, S. A. Baker-Zander, K. S. Weisz, D. F. Adams, L. Simonson, and S. A. Lukehart, N. Engl. J. Med. 325:539-543, 1991; G. R. Riviere, K. S. Weisz, D. F. Adams, and D. D. Thomas, Infect. Immun. 59:3377-3380, 1991; G. R. Riviere, K. S. Weisz, L. G. Simonson, and S. A. Lukehart, Infect. Immun. 59:2653-2657, 1991). In an attempt to phylogenetically analyze these pathogen-related oral spirochetes, we used immunomagnetic separation, combined with comparative sequence analysis of 16S rRNA genes amplified in vitro by the PCR. The bacteria were immunomagnetically enriched from subgingival plaque samples of patients with rapidly progressive periodontitis by using MAb H9-2 specific for the 37-kDa endoflagellum sheath protein of T. pallidum. After PCR amplification with universal eubacterial primers 16S rRNA gene fragments were cloned into Escherichia coli. A total of 20 randomly selected recombinants were analyzed by sequencing about 200 to 300 bases of the 500-bp inserts. All the spirochetal 16S rRNA sequences clustered to previously described, as yet uncultivable cluster 7 treponemes of group I (B. K. Choi, B. J. Paster, F. E. Dewhirst, and U. B. Göbel, Infect. Immun. 62:1889-1895, 1994). With a sequence similarity of 96.4% the most closely related cultivable treponeme was Treponema vincentii, which also belongs to the group I treponemes. Subsequent immunological analysis of cultured treponemes with MAb H9-2 revealed that only T. vincentii strains showed specific immunofluorescence or a characteristic 37-kDa band in immunoblots. We therefore conclude that pathogen-related oral spirochetes constitute a heterogeneous population of treponemes comprising T. vincentii and T. vincentii-related organisms that have common epitopes cross-reacting with MAb H9-2.

Treponema maltophilum sp. nov., a small oral spirochete isolated from human periodontal lesions

A novel culture medium for cultivation of fastidious oral anaerobes is described. This medium, OMIZ-Pat, consists of a rich chemically defined basal medium supplemented with asialofetuin, as well as yeast extract and Neopeptone fractions. Addition of 1 mg of rifampin per liter and 100 mg of fosfomycin per liter allowed routine isolation of spirochetes by a limit dilution method in 96-well plates containing liquid OMIZ-Pat. In addition to members of the four previously recognized species of oral treponemes (Treponema denticola, Treponema pectinovorum, Treponema socranskii, and Treponema vincentii), 26 previously undescribed spirochete strains belonging to one group were isolated. We propose the name Treponema maltophilum sp. nov. for these small spirochetes, which have two endoflagella; one endoflagellum is attached at each cell pole, and the endoflagella overlap in the middle of the cell. Growth of these organisms was dependent on a carbohydrate like D-arabinose, L-fucose, D-maltose, L-rhamnose, D-ribose, D-sucrose, or D-trehalose and was inhibited by fetal bovine serum. T. Maltophilum is distinguished from other oral Treponema species by its 16S rRNA sequence, its protein and antigen patterns as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting, and its characteristic alpha-glucosidase activity. The strains included in the new species on the basis of their 16S rRNA sequences are heterogeneous with respect to their alpha-fucosidase, and beta-glucuronidase activities, their dependence on N-acetylglucosamine, and their antigens as detected with patient antibodies. Strain BR is designated the type strain, and strains HO2A and PNA1 are reference strains of the new species.

Investigations on a Swiss area highly endemic for Echinococcus multilocularis

Anecdotal information suggested that a focus of hyperendemicity may be present in a small area of the Canton of Fribourg in Switzerland. Therefore, the prevalence of E. multilocularis was assessed both in the fox and the rodent population over a two-season-period. A high prevalence ranging between 47% and 56% was consistently determined in the fox population. An Arvicola terrestris population was infected at 39% in the first season of investigation and at 11% in the following season. A subsequent seroepidemiological survey in the population of inhabitants surrounding the area provided no indication of seroconversion and thus no indication of infection for humans. However, a longer-term survey will be needed to assess more precisely the risk of disease occurrence among these inhabitants.

Long-term Results on Quality of Life of Surgical Treatment of Obesity with Vertical Banded Gastroplasty

BACKGROUND: Few papers assess quality of life after vertical banded gastroplasty (VBG). METHODS: 100 patients with severe obesity (preoperatively mean BMI 41.7 kg m(2)) answered an interview 60 (+/- 2.5) months after VBG. RESULTS: There was no fatal outcome. Nine patients had pulmonary embolus; ten patients required reoperation because of stomal stenosis. Of the 89 patients that still bore a gastroplasty at the moment of the interview, 65 had lost more than 40% of their excess weight (= "success'). Improvement in quality of life of these 89 patients was reflected by significant diminution of depression and back pains. Significant diminution of arterial hypertension and improvement of professional satisfaction, and of social, physical, and sexual activity was significantly related to weight loss. CONCLUSION: VBG resulted generally in a favorable long-term effect on quality of life. However, patients should be informed preoperatively about potential side-effects such as possible persistent vomiting after several years, esophagitis and gastritis, restriction in the choice of foods and prolongation of meals.

Support of peptide-dependent growth of Bacteroides forsythus by synthetic fragments of haemoglobin or fetuin

The putative periodontal pathogen Bacteroides forsythus is a fastidious Gram-negative anaerobe with high proteolytic activity. For growth in a chemically defined medium containing insulin it required serum. Serum could be replaced by human haemoglobin or bovine asialofetuin, or by proteolytic fragments of these two proteins. Four such fragments consisting of from 8 to 18 amino acid residues were isolated and sequenced. Only aspartic acid, threonine, and valine were common to all peptides. An undecapeptide, Hba11, and a dodecapeptide, AsF12, were synthesized and found to be active at micromolar concentrations, but only when presented in combination with insulin. An analysis of amino acid requirements excluded a direct essential role of peptides as sources of amino acids in complete medium, except for valine. Should Bact. forsythus have an essential requirement for this amino acid, it could be satisfied by micromolar concentrations of peptide but not millimolar concentrations of the free amino acid in the absence of peptide. Bact. forsythus could salvage the essential amino acids lysine and isoleucine at 100-fold lower concentrations when presented in peptide-bound form compared to the free amino acids, and at 10-fold lower concentrations of peptide compared to Porphyromonas gingivalis W83, which in contrast to Bact. forsythus grew on free amino acids in the absence of insulin and peptides.

Aspartame as a source of essential phenylalanine for the growth of oral anaerobes

Phenylalanine and aspartic acid requirements were determined for 13 species of oral bacteria using the chemically defined medium OMIZ-W1. None of Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Eikenella corrodens, Selenomonas sputigena, Treponema pectinovorum, T. socranskii, or Wolinella recta required either of these amino acid constituents of aspartame (L-aspartyl-L-phenylalanine methylester). Phenylalanine was essential for the growth of Capnocytophaga gingivalis, Eubacterium timidum, Fusobacterium nucleatum, Porphyromonas gingivalis, T. denticola, and T. vincentii, while aspartic acid was not required. With the exception of E. timidum, all phenylalanine-dependent strains could grow when the free amino acid was replaced by aspartame at concentrations at least 10-fold lower than those used for aspartame as an artificial sweetener.

Growth of Porphyromonas gingivalis, Treponema denticola, T. pectinovorum, T. socranskii, and T. vincentii in a chemically defined medium

A chemically defined medium, OMIZ (Oral Microbiology and Immunology, Zürich)-W1 was developed. Medium OMIZ-W1 supports the long-term proliferation of a wide range of oral anaerobes, including representative strains of four Treponema species and Porphyromonas gingivalis. High concentrations of ascorbic acid and ammonium ions proved to be important for the growth of these organisms. T. denticola CD-1 grew in the absence of polyamines and long-chain fatty acids, T. pectinovorum and T. socranskii required polyamines, whereas T. vincentii depended on both polyamines and lecithin for growth. Specific requirements for purines and/or pyrimidines were detected, and these requirements could be used to distinguish Haemophilus-Actinobacillus group organisms. Some strains of P. gingivalis grew without vitamin K, while others were not satisfied by menadione but required its precursor 1,4-dihydroxy-2-naphthoic acid. Protoporphyrin IX or hemin equally satisfied the porphyrin requirements of P. gingivalis and Bacteroides forsythus, whereas ferrous sulfate was more efficiently used as a source of iron than was hemin. The cellular cohesiveness of P. gingivalis increased with high concentrations of hemin in the growth medium. Prevotella intermedia, B. forsythus, and several strains of P. gingivalis were more fastidious and required a protein or serum supplement to grow in medium OMIZ-W1.

Dependence of proliferation of Bacteroides forsythus on exogenous N-acetylmuramic acid

Bacteroides forsythus is the first wild-type or mutant bacterium found to require exogenous N-acetylmuramic acid for proliferation and maintenance of cell shape. This implies so far unknown pathways for peptidoglycan synthesis and a strict dependence of B. forsythus on other bacteria in its oral habitat. Addition of N-acetylmuramic acid to conventional bacteriological media allows routine cultivation of this fastidious organism.

Campylobacter-Wolinella group organisms are the only oral bacteria that form arylsulfatase-active colonies on a synthetic indicator medium

Most oral bacteria tested formed colonies on a chemically defined medium with a chromogenic arylsulfatase substrate. Arylsulfatase activity was, however, restricted to Campylobacter-Wolinella group organisms, including Wolinella recta, a possible periodontopathogen. W. recta was the only arylsulfatase-active species against which consistently high levels of antibody were detected in human sera.

Selected low-cohesion variants of Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus lack distinct antigens recognized by human antibodies

Actinobacillus actinomycetemcomitans OMZ 346 A and Haemophilus aphrophilus OMZ 384 A, isolated on a synthetic selective and differentiating agar, show the highly cohesive and wall adherent growth in liquid medium which is typical for all primary oral isolates of these species. From each of them a low cohesion variant, OMZ 346 F and OMZ 384 F, respectively, was obtained by selection for cells growing in suspension. Screening of Western blots of these four strains with several human sera revealed the loss of a 4000 Mr antigen in both F strains. Human antibodies bound to the 4000 Mr band material on preparative Western blots of the A strains were eluted with 4 M magnesium chloride. These antibodies showed no cross-reaction between the 4000 Mr material of the two closely related species.

[Lung function and symptoms in employees of poultry farms]

Environmental measurements were made in different types of poultry confinement buildings. Levels of total dust 1.6 meters above the ground averaged 5.0 mg/m3. Ammonia levels averaged about 13 ppm with peak values of about 50 ppm. To study possible respiratory problems of the people working in these confinement buildings, the ventilatory lung function was measured and an interrogation concerning respiratory symptoms was carried out by 26 (7 females, 19 males) poultry farmers. A very high prevalence (10 of 26) of obstructive ventilatory lung function changes was found. The FEV1 values of the exposed men were significantly lower than the predicted normal values (ECCS). An association between duration of exposure and pulmonary function exists.

Actin III and myofilaments in different muscles of wildtype and the mutant raised of Drosophila melanogaster

The mutation raised (rsd, 3-95.4) of Drosophila melanogaster causes flightlessness as a consequence of abnormalities in the fibrillar flight muscles (FFMs). In this muscle type actin III is neither synthesized nor accumulated while adult tubular muscles of rsd flies are indistinguishable from wildtype. This paper demonstrates ultrastructural defects in rds FFMs and extends the biochemical comparison of adult wildtype and rsd muscles to larval muscles and to embryo cells differentiating in culture. The FFMs of mature rsd flies contain thick filaments in irregular bundles, but no thin filaments. Normal Z-discs are virtually absent. Instead, a large number of Z-disc residues are present in stacks attached to short filaments on either side. In newly emerged rsd flies the disorganization is less pronounced. The adult tubular muscles and the supercontracting muscles of third-instar larvae of rsd can ultrastructurally not be distinguished from wildtype. The present biochemical results indicate that not only FFMs of mature and newly emerged adults are affected by the rsd genotype. Synthesis of actin III is not detectable in rsd FFMs which corresponds to the heavy structural defects. In addition to the lack of actin III synthesis in rsd FFMs, three unidentified proteins (52 kDa, 80 kDa, 90 kDa) which are specific for wildtype FFMs are also not synthesized in rsd flies. Among all other muscle types studied, all of which are morphologically unaffected, only adult tubular muscle of rsd genotype showed no biochemical effect. Larval supercontracting muscle as well as embryo cells differentiating in culture failed to synthesize actin III in the case of rsd cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Lower-extremity rotational problems in children. Normal values to guide management

We studied 1,000 normal lower extremities of children and adults in order to establish normal values for the rotational profile. The intrauterine position of the fetus molds the femur by rotating it laterally and molds the tibia by rotating it medially. These molding effects usually resolve spontaneously during infancy, and then genetically determined individual differences are unmasked. Rotational problems should be clinically evaluated and the findings compared with the normal values provided by this study. Out-toeing in infants, medial tibial torsion in toddlers, and medial femoral torsion in young children are extremes of a normal developmental pattern. In the vast majority, these rotational variations fall within the broad range of normal and require no treatment.

Pattern of peptide synthesis in Drosophila cell lines and their hybrids

Significant changes occurred in the rate of synthesis of several polypeptides in two different Drosophila cell lines following exposure to the steroid hormone, beta-ecdysone. For peptide 7/8, the synthetic rate increased by a factor of 10 in line S3 and by a factor of 1.3 in line MDR. In hormone-sensitive hybrids the rate increased by a factor of 3-4.5. For peptide 10 the synthetic rate decreased by a factor of 8 in line S3 but increased by a factor of 2 in line MDR. In hormone-sensitive hybrids the synthetic rate increased by a factor of 2-3. In hormone-insensitive cell lines no change in the rate of peptide synthesis occurred in the presence of hormone.

Acetylcholinesterase induction by beta-ecdysone in Drosophila cell lines and their hybrids

Drosophila S3 line cells maintain a high basal level of acetylcholinesterase (AChE) activity, which is lost and then reinduced following exposure to the steroid, beta-ecdysone. Electrophoretic studies indicate that the basal and reinduced AChE activities may be different isozymes. In contrast, MDR line cells have a low basal AChE activity which is induced to a modest level by hormone. In S3/MDR hybrids the high basal level phenotype is extinguished, and the hormone-induced AChE level is modest. MDER line cells, which continue to grow in the presence of beta-ecdysone and are therefore termed resistant, show a low basal AChE level that is not further elevated by hormone. This phenotype and response also occurred in beta-ecdysone-resistant S3/MDER hybrids.

Localization of arginine kinase in muscles fibres of Drosophila melanogaster

Arginine kinase (AK), a monomeric protein of mol. wt. 40 000, was purified from adult Drosophila melanogaster. Antiserum to AK was raised in rabbits; its specificity was established by immunodiffusion tests and by immunoreplicas of electropherograms. After electrophoresis in non-denaturing conditions, the immunoreactive material was shown to possess enzymatic activity. Localization of AK by indirect immunofluorescence on washed myofibrils showed that at least a fraction of the total cellular AK is bound to the contractile apparatus. In muscle fibres of third instar larvae and in isolated adult fibrillar flight muscle myofibrils, AK was localized within the Z-line region. Adult tubular muscle fibres (tergal depressor of the trochanter) showed fluorescence in the A-band. In all cases, the localization was independent of the state of contraction. Vertebrate B- and M-type creatine kinases have previously been localized at the Z-line and A-band (M-line) regions, respectively. Isoenzymic forms of AK have not been detected in Drosophila, however.