Carriage and Subtypes of Foodborne Pathogens Identified in Wild Birds Residing near Agricultural Lands in California: a Repeated Cross-Sectional Study.

Current California agricultural practices strive to comanage food safety and habitat conservation on farmland. However, the ecology of foodborne pathogens in wild bird populations, especially those avian species residing in proximity to fresh produce production fields, is not fully understood. In this repeated cross-sectional study, avifauna within agricultural lands in California were sampled over 1 year. Feces, oral swabs, and foot/feather swabs were cultured for zoonotic Salmonella spp., Escherichia coli O157:H7, and non-O157 Shiga toxin-producing E. coli (STEC) and characterized by serotyping and pulsed-field gel electrophoresis. Of 60 avian species sampled, 8 species (13.3%, bird groups of sparrows, icterids, geese, wrens, and kinglets) were positive for at least one of these foodborne pathogens. At the individual bird level, the detection of foodborne pathogens was infrequent in feces (n = 583; 0.5% Salmonella, 0.34% E. coli O157:H7, and 0.5% non-O157 STEC) and in feet/feathers (n = 401; 0.5% non-O157 STEC), and it was absent from oral swabs (n = 353). Several subtypes of public health importance were identified, including Salmonella enterica serotype Newport, E. coli O157:H7, and STEC serogroups O103 and O26. In late summer and autumn, the same STEC subtype was episodically found in several individuals of the same and different avian species, suggesting a common source of contamination in the environment. Sympatric free-range cattle shared subtypes of STEC O26 and O163 with wild geese. A limited rate of positive detection in wild birds provides insights into broad risk profile for contamination considerations but cannot preclude or predict risk on an individual farm.IMPORTANCE The shedding dynamics of foodborne pathogens by wild birds on farmland are not well characterized. This yearlong study sampled wild birds for foodborne pathogens within agricultural lands in northern California. There was a low prevalence of Salmonella spp., Escherichia coli O157:H7, and non-O157 Shiga-toxin producing E. coli (prevalence, 0.34% to 0.50%) identified in bird populations in this study. However, pathogens of public health importance (such as Salmonella Newport, E. coli O157:H7, and STEC O103 and O26) were identified in fecal samples, and two birds carried STEC on their feet or feathers. Identical pathogen strains were shared episodically among birds and between wild geese and free-range cattle. This result suggests a common source of contamination in the environment and potential transmission between species. These findings can be used to assess the risk posed by bird intrusions in produce fields and enhance policy decisions toward the comanagement of food safety and farmland habitat conservation.

Effect of soil type and temperature on survival of Salmonella enterica in poultry manure-amended soils.

The effects of soil type and temperature on the survival of a cocktail of five Salmonella enterica serotypes (Enteritidis, Infantis, Montevideo, Typhimurium and Zanzibar) in manure-amended soils under controlled laboratory conditions was assessed. Containers of clay loam or sandy soil, unaltered or amended with 2% (w/w) poultry manure, were inoculated with S. enterica (~5 log10 CFU per gram) and held at 5, 21 or 37°C for 6 weeks. Statistical analysis of the persistence of S. enterica identified a significant three-way interaction between soil type, manure amendment and temperature. Clay loam soils and lower temperatures tended to support S. enterica persistence over 6 weeks with only 1- and 2-log reductions respectively. In contrast, sand and higher temperatures resulted in a 4-log and either 3- to 4-log reductions respectively. Manure amendment had an overarching effect of reducing die-off of S. enterica in comparison with unamended soils. This study highlights that a large component of variation of the rate of S. enterica reduction in soils may be attributed to combinations of environmental factors, in particular, soil type and temperature. It further underscores the importance of risk management strategies and industry guidelines based on local data and that reflect the diversity of prevailing horticultural production environments. SIGNIFICANCE AND IMPACT OF THE STUDY: The persistence of Salmonella enterica in soil environments was shown to be significantly influenced by a range of individual and interacting environmental effects, including temperature, soil type and amendment addition. This indicates that current horticultural food safety management systems which employ a uniform prescribed exclusion period between application of manure and time of harvest may be unfit for purpose under certain conditions by either underestimating or overestimating pathogen die-off. These findings support exclusion periods that account for a range of environmental factors including temperature, soil type and growing region that may be more appropriate to manage microbiological risks associated with soil which has been amended with manure.

Multimodal imaging of a tescalcin (TESC)-regulating polymorphism (rs7294919)-specific effects on hippocampal gray matter structure.

In two large genome-wide association studies, an intergenic single-nucleotide polymorphism (SNP; rs7294919) involved in TESC gene regulation has been associated with hippocampus volume. Further characterization of neurobiological effects of the TESC gene is warranted using multimodal brain-wide structural and functional imaging. Voxel-based morphometry (VBM8) was used in two large, well-characterized samples of healthy individuals of West-European ancestry (Münster sample, N=503; SHIP-TREND, N=721) to analyze associations between rs7294919 and local gray matter volume. In subsamples, white matter fiber structure was investigated using diffusion tensor imaging (DTI) and limbic responsiveness was measured by means of functional magnetic resonance imaging (fMRI) during facial emotion processing (N=220 and N=264, respectively). Furthermore, gene x environment (G × E) interaction and gene x gene interaction with SNPs from genes previously found to be associated with hippocampal size (FKBP5, Reelin, IL-6, TNF-α, BDNF and 5-HTTLPR/rs25531) were explored. We demonstrated highly significant effects of rs7294919 on hippocampal gray matter volumes in both samples. In whole-brain analyses, no other brain areas except the hippocampal formation and adjacent temporal structures were associated with rs7294919. There were no genotype effects on DTI and fMRI results, including functional connectivity measures. No G × E interaction with childhood maltreatment was found in both samples. However, an interaction between rs7294919 and rs2299403 in the Reelin gene was found that withstood correction for multiple comparisons. We conclude that rs7294919 exerts highly robust and regionally specific effects on hippocampal gray matter structures, but not on other neuropsychiatrically relevant imaging markers. The biological interaction between TESC and RELN pointing to a neurodevelopmental origin of the observed findings warrants further mechanistic investigations.

Identification of a biological signature for schizophrenia in serum.

Biomarkers are now used in many areas of medicine but are still lacking for psychiatric conditions such as schizophrenia (SCZ). We have used a multiplex molecular profiling approach to measure serum concentrations of 181 proteins and small molecules in 250 first and recent onset SCZ, 35 major depressive disorder (MDD), 32 euthymic bipolar disorder (BPD), 45 Asperger syndrome and 280 control subjects. Preliminary analysis resulted in identification of a signature comprised of 34 analytes in a cohort of closely matched SCZ (n=71) and control (n=59) subjects. Partial least squares discriminant analysis using this signature gave a separation of 60-75% of SCZ subjects from controls across five independent cohorts. The same analysis also gave a separation of ~50% of MDD patients and 10-20% of BPD and Asperger syndrome subjects from controls. These results demonstrate for the first time that a biological signature for SCZ can be identified in blood serum. This study lays the groundwork for development of a diagnostic test that can be used as an aid for distinguishing SCZ subjects from healthy controls and from those affected by related psychiatric illnesses with overlapping symptoms.

Growth of Salmonella enterica in foliar pesticide solutions and its survival during field production and postharvest handling of fresh market tomato.

AIMS: To evaluate in vitro the growth kinetics of Salmonella enterica in pesticide solutions labelled for fresh market tomato and the effect of ag-chemical application with contaminated water to tomatoes during field production. METHODS AND RESULTS: The capacity of pesticide formulations in the survival of S. enterica was evaluated in vitro and on tomato surfaces during field production. Most pesticides had ability to maintain the growth of Salmonella, however, specific pesticides can also support its growth, which was also dependent on the water composition and temperature to which pesticide solutions were held. Salmonella applied to field grown tomatoes through pesticide application was able to survive up to 15 days in up to 80% of the collected samples, even more postharvest washing with sodium hypochlorite was insufficient to completely mitigate the presence of Salmonella on tomato surfaces. CONCLUSIONS: This study provides further evidence that pesticides may support the growth of Salmonella, if introduced with source water and may elevate risk during foliar contact application beyond that of the water source alone. SIGNIFICANCE AND IMPACT OF STUDY: The study points out the importance of the microbiological quality of foliar contact water as a critical point to prevent contamination of fruits and vegetables from early stages of field production.

Detection of Salmonella spp. from large volumes of water by modified Moore swabs and tangential flow filtration.

This study compares the use of tangential flow filtration (TFF), normal flow filtration and modified Moore swabs (MMS) for the concentration and detection of Salmonella, spiked at 1-760 CFU l(-1), from 10 l of surface water. Two immunomagnetic separation (IMS) methods, Pathatrix and Dynabeads, for further concentration of Salmonella were compared following filtration and overnight enrichment. Detection of Salmonella by PCR, qPCR or culture-based methods was compared. TFF and MMS preformed equally well in concentrating Salmonella. MMS was able to consistently concentrate Escherichia coli O157:H7 for culture-based detection; only at the higher concentrations tested was the TFF able to consistently concentrate E. coli O157:H7 for culture-based detection. Salmonella, at population densities <10 CFU l(-1) in 10 l of spiked surface water, could be reliably (6/6) detected within 2 days by combining TFF or MMS, with IMS Pathatrix and qPCR. The theoretical limit of detection for Salmonella is considered to be sufficiently sensitive to meet all the practical screening purposes for surface waters in an agricultural setting intended for application to edible horticultural crops.

Neuropeptide S receptor gene -- converging evidence for a role in panic disorder.

Animal studies have suggested neuropeptide S (NPS) and its receptor (NPSR) to be involved in the pathogenesis of anxiety-related behavior. In this study, a multilevel approach was applied to further elucidate the role of NPS in the etiology of human anxiety. The functional NPSR A/T (Asn¹°7Ile) variant (rs324981) was investigated for association with (1) panic disorder with and without agoraphobia in two large, independent case-control studies, (2) dimensional anxiety traits, (3) autonomic arousal level during a behavioral avoidance test and (4) brain activation correlates of anxiety-related emotional processing in panic disorder. The more active NPSR rs324981 T allele was found to be associated with panic disorder in the female subgroup of patients in both samples as well as in a meta-analytic approach. The T risk allele was further related to elevated anxiety sensitivity, increased heart rate and higher symptom reports during a behavioral avoidance test as well as decreased activity in the dorsolateral prefrontal, lateral orbitofrontal and anterior cingulate cortex during processing of fearful faces in patients with panic disorder. The present results provide converging evidence for a female-dominant role of NPSR gene variation in panic disorder potentially through heightened autonomic arousal and distorted processing of anxiety-relevant emotional stimuli.

Variable agronomic practices, cultivar, strain source and initial contamination dose differentially affect survival of Escherichia coli on spinach.

AIMS: Greenhouse and field trials were conducted under different agronomic practices and inoculum doses of environmental Escherichia coli and attenuated E. coli O157:H7, to comparatively determine whether these factors influence their survival on leaves and within the rhizosphere. METHODS AND RESULTS: Hydroponic conditions: E. coli spray-inoculated at log 4 CFU ml(-1) was recovered from leaf surfaces at a mean population of 1·6 log CFU g(-1) at 15 days. E. coli O157:H7 sprayed at log 2 or 4 CFU ml(-1) levelled off on spinach leaf surfaces at a mean average population of 1·4 log CFU g(-1) after 14 days, regardless of initial dose. Quantitative recovery was inconsistent across leaf developmental age. Field conditions: Average populations of E. coli O157:H7 spray-inoculated at log 1·45 or 3·4 CFU m(-2) levelled off at log 1·2 CFU g(-1) over a 14-day period. Pathogen recovery from leaves was inconsistent when compared to regularly positive detection on basal shoot tissue. Pathogen recovery from soil was inconsistent among sampling locations. Moisture content varied up to 40% DW and was associated with 50% (P < 0·05) decrease in positive locations for E. coli O157:H7 but not for E. coli. CONCLUSIONS: Overall, similar populations of environmental E. coli and E. coli O157:H7 were recovered from plants despite differences in inoculum dose and agronomic conditions. Strain source had a significant impact on the quantitative level and duration of survival on leaves and in soil. Water availability appeared to be the determinant factor in survival of E. coli and E. coli O157:H7; however, E. coli showed greater environmental fitness. SIGNIFICANCE AND IMPACT OF THE STUDY: Persistence of surrogate, indicator E. coli and E. coli O157:H7, irrespective of variable growing conditions in spinach is predominantly limited by water availability, strain source and localization within the plant. These findings are anticipated to ultimately be adopted into routine and investigative pathogen testing protocols and mechanical harvest practices of spinach.

[Neurogenetics of emotional processes. Neuroimaging findings as endophenotypes for depression]. / Neurogenetik emotionaler Prozesse. Neuroimaging-Befunde als Endophänotypen der Depression.

Major depression is one of the most frequent and serious psychiatric diseases. Although the disease is highly heritable, the search for candidate genes has been of limited success hitherto. The complex, polygenetic hereditary transmissions coding for heterogeneous, clinically defined phenotypes such as major depression may be better identified using the endophenotype approach. A recent study, reporting an association of the risk allele in a serotonin transporter polymorphism (5-HTTLPR) with increased amygdala responsiveness to aversive stimuli, stimulated the new research field of imaging genetics, which is characterized by the choice of neurobiological activity patterns as endophenotypes. This review discusses recent studies from this rapidly growing research field, focussing on genetic effects on cortico-limbic circuitries during emotion processing. Evidence is reviewed suggesting that potential risk-alleles for depression are associated with functional cortico-limbic abnormalities, which frequently occur in patients with major depression.

Gene-splicing experiment.

In the article "Windows on a new cosmology" by George Lake (18 May, p. 675), the caption for figure 4(b) on page 680 was incorrect. The photograph shows the electric dipole moment apparatus at the Institute Laue-Langevin in Grenoble, France [courtesy of N. Ramsey].

Comparative evaluation of practical functionality of rapid test format kits for detection of Escherichia coli O157:H7 on lettuce and leafy greens.

Multistate outbreaks of Escherichia coli O157:H7 infection in 2005 and 2006 associated with fresh and especially minimally processed produce greatly escalated the application of rapid pathogen detection systems to safety management in this food category. Pathogen testing was rapidly integrated into preharvest qualification for field lots, incoming raw produce, or final product. The raw produce and final product were incorporated into test-and-hold programs, typically within a 10-h time frame. To enhance consumer safety and provide guidance for the industry, an assessment of selected kits in comparison to a culture-based method was undertaken. Four primary kits were compared: the Neogen Reveal, SDI RapidChek, BioControl GDS O157, and Qualicon BAX O157 MP. Nine different leafy greens were freshly harvested and inoculated with a five-isolate mixture of E. coli O157:H7 at 10 CFU/25 g of sample, and cultures were enriched following the specified protocol. The PCR method was most consistent for identifying the presence of the inoculated pathogen in the shortest period of time. For the red-pigmented leafy vegetables red butter lettuce, curly endive, red lettuce, and lollo rosa, 13, 38, 88, and 100% false-negative results, respectively, were obtained with the immunoassays, but PCR detection was minimally affected. Immunoassays were negatively affected by delays in achieving critical threshold populations during the allowed enrichment period. Leafy green type, temperature abuse, and preharvest environment were unlikely to affect the results of PCR-based kits. Findings strongly suggest that product testing systems using 8-h detection cutoffs may give false-negative results. These issues become very important in high-throughput testing and retest protocols for presumptive pathogen-positive lots of produce.

[Schizophrenia-like personality disorders]. / Schizophrenienahe Persönlichkeitsstörungen.

According to DSM-IV the cluster A personality disorders include paranoid, schizoid, and schizotypal personality disorders. There exists a phenomenological similarity between the experience and behaviour of the so-called odd or eccentric personality disorders and the symptoms of schizophrenia. Evidence of common etiological factors is still the best for the schizotypal personality disorder. The cluster A personality disorders are among the less common personality disorders with a high co-occurrence. Present findings about the neurobiological substrate of the schizotypal personality disorder are discussed also taking neuropsychological results into consideration. A central prerequisite of psychotherapeutic and pharmacological treatment of cluster A personality disorders is a strong therapeutic patient relationship.

Serotonergic genes modulate amygdala activity in major depression.

Serotonergic genes have been implicated in the pathogenesis of depression probably via their influence on neural activity during emotion processing. This study used an imaging genomics approach to investigate amygdala activity in major depression as a function of common functional polymorphisms in the serotonin transporter gene (5-HTTLPR) and the serotonin receptor 1A gene (5-HT(1A)-1019C/G). In 27 medicated patients with major depression, amygdala responses to happy, sad and angry faces were assessed using functional magnetic resonance imaging at 3 Tesla. Patients were genotyped for the 5-HT(1A)-1019C/G and the 5-HTTLPR polymorphism, including the newly described 5-HTT-rs25531 single nucleotide polymorphism. Risk allele carriers for either gene showed significantly increased bilateral amygdala activation in response to emotional stimuli, implicating an additive effect of both genotypes. Our data suggest that the genetic susceptibility for major depression might be transported via dysfunctional neural activity in brain regions critical for emotion processing.

N-acetylaspartate levels of left frontal cortex are associated with verbal intelligence in women but not in men: a proton magnetic resonance spectroscopy study.

The left frontal cortex plays an important role in executive function and complex language processing inclusive of spoken language. The purpose of this work was to assess metabolite levels in the left and right prefrontal cortex and left anterior cingulum by proton magnetic resonance spectroscopy and relate results to verbal intelligence (Wechsler Adult Intelligence Scale revised) in a sample of college-educated healthy volunteers (dorsolateral prefrontal cortex [DLPFC]: n=52, 23 females, and left anterior cingulum: n=62, 22 females; age range: 20-75 years). In women only, N-acetylaspartate in the DLPFC and in the left anterior cingulate cortex was positively correlated with vocabulary scores. Our data support the hypothesis of existing gender differences regarding the involvement of the left frontal cortex in verbal processing as reflected in different correlations of specific metabolites with verbal scores.

Backward masking in schizophrenia: time course of visual processing deficits during task performance.

Backward masking deficits have been put forward as potential psychological markers for vulnerability to schizophrenia. This study was conducted to investigate whether schizophrenic patients improve their performance on a backward masking task during a single test session. The ability of a degraded stimulus version of the masking task to act as a specific diagnostic marker for paranoid schizophrenia (versus affective disorder) was also investigated. The backward masking task was performed on 18 paranoid schizophrenic patients, 18 unipolar depressed patients, and 18 non-psychiatric controls. Paranoid schizophrenic patients were included because they tend to show normal performance with traditional masking protocols. Schizophrenic patients made significantly more detection errors compared to depressives and non-psychiatric controls where interstimulus intervals (ISIs) longer than 14 ms were used. Unlike depressed patients and non-psychiatric controls, schizophrenic patients showed no reduction in error rate during the entire period over which the backward masking task was performed. The constant error rate which was observed at an ISI of 114 ms suggests that schizophrenic patients cannot attenuate the disruption effect due to deflection of attention from the target to the mask. The backward masking deficit in schizophrenia appears to arise from a temporarily stable visual processing impairment in performance within a single test session.

Paranoid schizophrenia: non-specificity of neuropsychological vulnerability markers.

During stages of remission, patients with paranoid schizophrenia seldom show severe attentional or information-processing dysfunctions, except in cases of long-term chronicity. The diagnostic specificity of four putative psychological vulnerability indicators of schizophrenia - the Span of Apprehension, the degraded stimulus Continuous Performance Test (dsCPT), the degraded stimulus visual backward masking task and the Wisconsin Card Sorting Test (WCST) - was examined in a group of patients with paranoid schizophrenia. Since no single test seems to identify all patients, the use of a combination of measures may be a useful strategy. Accordingly, the four tests were administered to 18 paranoid schizophrenic patients, 18 depressed patients and 18 normal subjects. Paranoid schizophrenic patients could be distinguished from normal subjects primarily on the basis of their performance on the backward masking task and secondarily by the dsCPT and the WCST. Paranoid schizophrenic and depressed patients could be differentiated to some extent by their performance on an information-mask condition of the backward masking task. Thus, of the four measures studied, only the degraded stimulus backward masking appeared to be a specific indicator of paranoid schizophrenia.

Standardization of a method to determine the efficacy of sanitizers in inactivating human pathogenic microorganisms on raw fruits and vegetables.

The efficacy of sanitizers in killing human pathogenic microorganisms on a wide range of whole and fresh-cut fruits and vegetables has been studied extensively. Numerous challenge studies to determine the effects of storage conditions on survival and growth of pathogens on raw produce have also been reported. Results of these studies are often difficult to assess because of the lack of sufficient reporting of methods or, comparatively, because of variations in procedures for preparing and applying inocula to produce, conditions for treatment and storage, and procedures for enumerating pathogens. There is a need for a standard method to accurately determine the presence and populations of pathogenic microorganisms on produce. The adoption of standard, well-characterized reference strains would benefit a comparative assessment of a basic method among laboratories. A single protocol will not be suitable for all fruits and vegetables. Modifications of a basic method will be necessary to achieve maximum recovery of pathogens on various types of produce subjected to different sanitizer or storage treatments. This article discusses parameters that must be considered in the course of developing a basic standard method against which these modifications could be made.

[A critique of the construct "alexithymia" and its measurement--the weakness of self-report and the opportunities of an objective assessment approach]. / Eine Kritik des Konstruktes "Alexithymie" und seiner Erfassung--Von der Schwäche der Selbstbeschreibung und den Möglichkeiten eines objektiven Untersuchungsansatzes.

Approximately thirty years ago the term alexithymia was coined but it is still open which characteristics have to be considered core symptoms of alexithymia. A selective review of recent expert definitions reveals dynamism in defining the alexithymia construct. At present, the self-report Toronto-Alexithymia-Scales (TAS) are the most frequently used measures of alexithymia. Empirical findings regarding various aspects of validity (factorial, concurrent, and experimental construct validity data) question the validity of the Toronto-Alexithymia-Scales. Alexithymia as measured by the TAS appears not to be consistently related to physiological, affect decoding or affective vigilance characteristics. The heterogeneity of the results could be due to the fact that non-alexithymic persons such as depressed or socially anxious individuals yield high scores on the TAS; on the other hand self-report appears to be in principle a methodologically inadequate approach for the assessment of alexithymia. Objective or direct measures of alexithymic characteristics as the Levels of Emotional Awareness Scale or the prototypicity analysis of mood diaries based on adjective checklists seem to be promising assessment methods for future research.

Detection of facial expressions of emotions in depression.

Research on perceptual and attentional processes in depression has shown that depressed as opposed to nondepressed individuals do not exhibit a positive perceptual bias in multistimulus representations. In the present study a face-in-the-crowd task was applied to examine the relationship between depression and spatial detection of facial expression of positive and negative emotions. A face-in-the-crowd task was administered to 30 subjects (15 clinically stabilized depressed inpatients and 15 normal subjects) using displays of schematic faces. Depressed subjects showed no performance differences in the detection of negative faces and no differences in decision latency for the control condition (all neutral faces) compared to normal subjects. Depressed subjects, however, were significantly slower in responding to positive faces than normal subjects. Our data suggest that depressive mood is associated with a reduced spatial attention to positive facial expression and not with an abnormal spatial processing of negative facial expression. An implication is that lowered vigilance for facial expressions of joy and happiness may affect adversely interpersonal relationships in depressed subjects.