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BACE1 encodes for the beta-site amyloid precursor protein cleaving enzyme 1 or β-secretase. Genetic deletion of Bace1 leads to behavioral alterations and affects midbrain dopaminergic signaling and memory processes. In order to further understand the role of BACE1 in brain function and behavior, we performed microarray transcriptome profiling and gene pathway analysis in the hippocampus of BACE1-deficient mice compared to wild type. We identified a total of 91 differentially expressed genes (DEGs), mostly enriched in pathways related to the immune and inflammation systems, particularly IL-9 and NF-κB activation pathways. Serum levels of IL-9 were elevated in BACE1-deficient mice. Our network analysis supports an intimate connection between immune response via NF-κB and BACE1 signaling through the NRG1/Akt1 pathway. Our findings warrant future mechanistic studies to determine if BACE1 signaling and the IL-9 pathway interact to alter behavior and brain function. This study opens new avenues in the investigation of hippocampus-related neuroimmunological and neuroinflammation-associated disorders. [ABSTRACT FROM AUTHOR]

The tomato leaf miner, Tuta absoluta (Lepidoptera: Gelechiidae), is a major invasive pest that has spread throughout many countries in the Mediterranean basin and parts of Asia over the last decade. The control of T. absoluta has relied heavily on the use of chemical insecticides, a strategy that has led to the evolution of resistance. In this study, biological and molecular methods were used to determine the susceptibility of five strains of T. absoluta to the organophosphate chlorpyrifos and to investigate the molecular mechanisms underlying resistance to this class of insecticides. High levels of resistance to chlorpyrifos were observed in all five strains tested. Cloning and sequencing of the gene encoding the organophosphate target site, ace-1, of T. absoluta revealed the presence of an alanine to serine substitution at a position that has been previously linked with organophosphate resistance across a range of different insect and mite species. The presence of this mutation at high frequency in T. absoluta populations originating from various countries further supports the suggestion that the rapid expansion of this species is, in part, mediated by the resistance of this pest to chemical insecticides. [ABSTRACT FROM AUTHOR]

The development of insecticide resistance in insect pests of crops is a growing threat to sustainable food production, and strategies that slow the development of resistance are therefore urgently required. The insecticide synergist piperonyl butoxide (PBO) inhibits certain insect detoxification systems and so may delay the evolution of metabolic resistance. In the current study we characterized resistance development in the silverleaf whitefly, Bemisia tabaci, after selection with either a neonicotinoid (thiacloprid) or pyrethroid ( alpha-cypermethrin) insecticide alone or in combination with PBO. Resistance development was significantly suppressed (> 60%) in the line selected with alpha-cypermethrin + PBO compared to the line selected with alpha-cypermethrin alone. RNA sequencing (RNAseq) analyses revealed an increase in frequency of a knock-down resistance mutation but no differentially expressed genes were identified that could explain the sensitivity shift. No significant difference was observed in the level of resistance between the thiacloprid and thiacloprid + PBO selected lines, and RNA sequencing (RNAseq) analyses revealed that the cytochrome P450 monooxygenase CYP6CM1, known to metabolize neonicotinoids, was significantly upregulated (>10-fold) in both lines. The findings of this study demonstrate that PBO used in combination with certain insecticides can suppress the development of resistance in a laboratory setting; however, the mechanism by which PBO supresses resistance development remains unclear. [ABSTRACT FROM AUTHOR]

Biomechanical headforms are used for helmet certification testing and reconstructing helmeted head impacts; however, their biofidelity and direct applicability to human head and helmet responses remain unclear. Dynamic responses of cadaver heads and three headforms and residual foam liner deformations were compared during motorcycle helmet impacts. Instrumented, helmeted heads/headforms were dropped onto the forehead region against an instrumented flat anvil at 75, 150, and 195 J. Helmets were CT scanned to quantify maximum liner crush depth and crush volume. General linear models were used to quantify the effect of head type and impact energy on linear acceleration, head injury criterion (HIC), force, maximum liner crush depth, and liner crush volume and regression models were used to quantify the relationship between acceleration and both maximum crush depth and crush volume. The cadaver heads generated larger peak accelerations than all three headforms, larger HICs than the International Organization for Standardization (ISO), larger forces than the Hybrid III and ISO, larger maximum crush depth than the ISO, and larger crush volumes than the DOT. These significant differences between the cadaver heads and headforms need to be accounted for when attempting to estimate an impact exposure using a helmet's residual crush depth or volume. [ABSTRACT FROM AUTHOR]

Honey bees, Apis mellifera, are markedly less sensitive to neonicotinoid insecticides containing a cyanoimino pharmacophore than to those with a nitroimino group. Although previous work has suggested that this results from enhanced metabolism of the former by detoxification enzymes, the specific enzyme(s) involved remain to be characterized. In this work, a pretreatment of honey bees with a sublethal dose of thiacloprid resulted in induced insensitivity to the same compound immediately following thiacloprid feeding. A longer pretreatment time resulted in no, or increased, sensitivity. Transcriptome profiling, using microarrays, identified a number of genes encoding detoxification enzymes that were over-expressed significantly in insecticide-treated bees compared with untreated controls. These included five P450s, CYP6BE1, CYP305D1, CYP6AS5, CYP315A1, CYP301A1, and a carboxyl/cholinesterase (CCE) CCE8. Four of these P450s were functionally expressed in Escherichia coli and their ability to metabolize thiacloprid examined by liquid chromatography-mass spectrometry (LC-MS) analysis. [ABSTRACT FROM AUTHOR]

Smith-Kingsmore syndrome (SKS) is a rare autosomal dominant syndrome resulting from mutations in the MTOR gene located on chromosome 1p36. This case outlines the antenatal USS and MR findings of SKS which, to the best of our knowledge, have not been previously reported. MR imaging in children with SKS shows anomalies including dilatation of the ventricular system, callosal anomalies, polymicrogyria and loss of white matter. [Extracted from the article]

β-Site APP-cleaving Enzyme 1 ( BACE1) is a protease that has been linked to schizophrenia, a severe mental illness that is potentially characterized by enhanced dopamine (DA) release in the striatum. Here, we used acute amphetamine administration to stimulate neuronal activity and investigated the neurophysiological and locomotor-activity response in BACE1-deficient ( BACE1−/−) mice. We measured locomotor activity at baseline and after treatment with amphetamine (3.2 and 10 mg/kg). While baseline locomotor activity did not vary between groups, BACE1−/− mice exhibited reduced sensitivity to the locomotor-enhancing effects of amphetamine. Using high-performance liquid chromatography (HPLC) to measure DA and DA metabolites in the striatum, we found no significant differences in BACE1−/− compared with wild-type mice. To determine if DA neuron excitability is altered in BACE1−/− mice, we performed patch-clamp electrophysiology in putative DA neurons from brain slices that contained the substantia nigra. Pacemaker firing rate was slightly increased in slices from BACE1−/− mice. We next measured G protein-coupled potassium currents produced by activation of D2 autoreceptors, which strongly inhibit firing of these neurons. The maximal amplitude and decay times of D2 autoreceptor currents were not altered in BACE1−/− mice, indicating no change in D2 autoreceptor-sensitivity and DA transporter-mediated reuptake. However, amphetamine (30 µ m)-induced potassium currents produced by efflux of DA were enhanced in BACE1−/− mice, perhaps indicating increased vesicular DA content in the midbrain. This suggests a plausible mechanism to explain the decreased sensitivity to amphetamine-induced locomotion, and provides evidence that decreased availability of BACE1 can produce persistent adaptations in the dopaminergic system. [ABSTRACT FROM AUTHOR]

We present the design, description, calibration procedure, and an analysis of systematic effects for an apparatus designed to measure the rotation of the plane of polarization of a transversely polarized slow neutron beam as it passes through unpolarized matter. This device is the neutron optical equivalent of a crossed polarizer/analyzer pair familiar from light optics. This apparatus has been used to search for parity violation in the interaction of polarized slow neutrons in matter. Given the brightness of existing slow neutron sources, this apparatus is capable of measuring a neutron rotary power of dφ/dz = 1 x 10-7 rad/m. [ABSTRACT FROM AUTHOR]

The pollen beetle Meligethes aeneus is the most important coleopteran pest in European oilseed rape cultivation, annually infesting millions of hectares and responsible for substantial yield losses if not kept under economic damage thresholds. This species is primarily controlled with insecticides but has recently developed high levels of resistance to the pyrethroid class. The aim of the present study was to provide a transcriptomic resource to investigate mechanisms of resistance. cDNA was sequenced on both Roche (Indianapolis, IN, USA) and Illumina (LGC Genomics, Berlin, Germany) platforms, resulting in a total of ∼53 m reads which assembled into 43 396 expressed sequence tags ( ESTs). Manual annotation revealed good coverage of genes encoding insecticide target sites and detoxification enzymes. A total of 77 nonredundant cytochrome P450 genes were identified. Mapping of Illumina RNAseq sequences (from susceptible and pyrethroid-resistant strains) against the reference transcriptome identified a cytochrome P450 ( CYP6BQ23) as highly overexpressed in pyrethroid resistance strains. Single-nucleotide polymorphism analysis confirmed the presence of a target-site resistance mutation ( L1014F) in the voltage-gated sodium channel of one resistant strain. Our results provide new insights into the important genes associated with pyrethroid resistance in M. aeneus. Furthermore, a comprehensive EST resource is provided for future studies on insecticide modes of action and resistance mechanisms in pollen beetle. [ABSTRACT FROM AUTHOR]

Objective Childhood maltreatment ( CM) has been associated with several diseases in adult life, including diabetes, obesity and mental disorders. Inflammatory conditions have been postulated as possible mediators of this relationship. The aim was to conduct a systematic review regarding the association between CM and inflammatory markers in adulthood. Method A literature search of the Pub Med, ISI, EMBASE and Psych INFO databases was conducted. The key terms used were as follows: 'Child Maltreatment', 'Childhood Trauma', 'Early Life Stress', 'Psychological Stress', 'Emotional Stress', 'Child Abuse' and 'Child Neglect'. They were cross-referenced separately with the terms: 'C-reactive Protein (CRP)', 'Tumor Necrosis Factor', 'Cytokine', 'Interleukin', 'Inflammatory' and 'Inflammation'. Results Twenty articles remained in the review after exclusion criteria were applied. Studies showed that a history of CM was associated with increased levels of CRP, fibrinogen and proinflammatory cytokines. Increased levels of circulating CRP in individuals with a history of CM were the most robust finding among the studies. Data about anti-inflammatory mediators are still few and inconsistent. Conclusion Childhood maltreatment is associated with a chronic inflammatory state independent of clinical comorbidities. However, studies are heterogeneous regarding CM assessment and definition. Important methodological improvements are needed to better understand the potential impact of CM on inflammatory response. [ABSTRACT FROM AUTHOR]

Bemisia tabaci has developed high levels of resistance to many insecticides including the neonicotinoids and there is strong evidence that for some compounds resistance is stage-specific. To investigate the molecular basis of B. tabaci resistance to the neonicotinoid thiamethoxam we used a custom whitefly microarray to compare gene expression in the egg, nymph and adult stages of a thiamethoxam-resistant strain ( TH- R) with a susceptible strain ( TH- S). Gene ontology and bioinformatic analyses revealed that in all life stages many of the differentially expressed transcripts encoded enzymes involved in metabolic processes and/or metabolism of xenobiotics. Several of these are candidate resistance genes and include the cytochrome P450 CYP6 CM1, which has been shown to confer resistance to several neonicotinoids previously, a P450 belonging to the Cytochrome P450s 4 family and a glutathione S-transferase ( GST) belonging to the sigma class. Finally several ATP-binding cassette transporters of the ABCG subfamily were highly over-expressed in the adult stage of the TH- R strain and may play a role in resistance by active efflux. Here, we evaluated both common and stage-specific gene expression signatures and identified several candidate resistance genes that may underlie B. tabaci resistance to thiamethoxam. [ABSTRACT FROM AUTHOR]

The brown planthopper, Nilaparvata lugens, is an economically significant pest of rice throughout Asia and has evolved resistance to many insecticides including the neonicotinoid imidacloprid. The resistance of field populations of N. lugens to imidacloprid has been attributed to enhanced detoxification by cytochrome P450 monooxygenases (P450s), although, to date, the causative P450(s) has (have) not been identified. In the present study, biochemical assays using the model substrate 7-ethoxycoumarin showed enhanced P450 activity in several resistant N. lugens field strains when compared with a susceptible reference strain. Thirty three cDNA sequences encoding tentative unique P450s were identified from two recent sequencing projects and by degenerate PCR. The mRNA expression level of 32 of these was examined in susceptible, moderately resistant and highly resistant N. lugens strains using quantitative real-time PCR. A single P450 gene ( CYP6ER1) was highly overexpressed in all resistant strains (up to 40-fold) and the level of expression observed in the different N. lugens strains was significantly correlated with the resistance phenotype. These results provide strong evidence for a role of CYP6ER1 in the resistance of N. lugens to imidacloprid. [ABSTRACT FROM AUTHOR]

This research was completed as part of an ongoing effort to characterise human thoracic response to belt loading in a well controlled and repeatable laboratory environment. This paper presents the results of eight tests conducted on three post-mortem human subjects. The sled test environment provides realistic occupant kinematics and restraint interaction in the inertial environment of a vehicle collision, but is too complex for detailed analysis of thoracic deformation under belt loading. To study in more detail the kinematics of the chest when loaded anteriorly by a seat belt, three male post-mortem human surrogates (31-62 years of age) were mounted on a stationary apparatus that supported the spine and shoulder in a configuration comparable to that achieved in a 48 km/h sled test at the time of maximum chest deformation. The belt was positioned across the anterior torso with attachments at D-ring and buckle locations based on the geometry of a mid-sized sedan. The belt was attached to a trolley driven by a hydraulic ram linked to a universal test machine. Ramp experiments were conducted at rates of 0.5 m/s, 0.9 m/s and 1.2 m/s. Average peak sternal displacements ranged from 13% to 23% of chest depth measured at the central sternum. Belt loads and spinal reaction loads were measured along with six degree-of-freedom (DOF) displacement data of the sternum, 4th and 8th ribs anteriorly, 8th and 10th ribs posteriorly, and acromia bilaterally. Three DOF targets were mounted to the distal clavicles, 8th ribs laterally and along the path of the belt. The targets were tracked optically by a high speed 16-camera motion capture system (VICON MX™) in a calibrated space around the torso. Post-test analysis of the target motion included decomposition of the trajectories into Cartesian coordinate displacements with respect to a spine fixed coordinate system. The results showed that the chest deformation closely followed the belt loading regionally with a trough developing where the belt contacted the chest. The anterior rib targets exhibited three-dimensional (3D) translational motion. Displacements in the X direction (anterior-posterior) were the largest, however the Z (vertical) and Y (lateral) displacements comprised nearly 35% and 10% respectively of the total resultant deflection measured at the sternum. Peak posterior deformations were significantly (p < .001) lower than those observed at anterior locations and were below 7 mm except for the final injurious tests in which the peak posterior deformation averaged 13.4 mm (approximately 22% of the average peak anterior ribcage deformation in the injurious tests). Overall, the results provide a detailed 3D mapping of the chest deformation under belt loading, which should be considered in the future development of physical and computational models of the thorax. [ABSTRACT FROM AUTHOR]

Summary: This study reports on the distribution of pyrethroid and DDT resistance and the L1014F knockdown resistance (kdr) mutation in Anopheles gambiae s.l. populations from 21 localities in three different climatic zones of Burkina Faso from August to October 2006. The susceptibility of these populations was assessed by bioassay using DDT (4%), permethrin (1%) and deltamethrin (0.05%). Anopheles gambiae were resistant to both permethrin and DDT in the Sudanian regions but were susceptible in the central and sahelian areas and susceptible to deltamethrin at all sites except Orodara, although mortality values in some populations were close to the resistance threshold. The kdr frequency varied from 0.4 to 0.97 in populations from the Sudanian region and was lower in populations from the Sudano-sahelian and sahelian areas (0.047 to 0.54). Compared to the last survey of kdr in An. gambiae populations conducted in 2000, the kdr frequency did not differ in the S form but had increased in the M form (0.6), with an extended distribution into the Sudano-sahelian region. The frequency of kdr was also found to have increased in An. arabiensis populations (0.28), where it was formerly reported in only a single specimen. These results have practical significance for malaria vector control programs. [Copyright &y& Elsevier]

Copyright of Tropical Medicine & International Health is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fundulus heteroclitus from six sites throughout the Hackensack Meadowlands District in northern NJ, U.S.A., were examined. Differences in behaviour (surfacing, conspicuousness and activity) were compared to gill infection intensity. Fish from populations infected with >1500 digenean metacercariae of Ascocotyle phagicola diminuta and Echinochasmus schwartzi, spent significantly more time at the water surface and exhibited significantly more conspicuous behaviour ( e.g. jerking) than fish from less parasitized populations. This more conspicuous behaviour has the potential to increase trophic transmission of the parasite to its definitive wading-bird host. [ABSTRACT FROM AUTHOR]

Brain tumors are associated with genetic alterations of oncogenes and tumor suppressor genes. Accumulation of reactive oxygen species (ROS) in cells leads to oxidative stress-induced damage, resulting in tumorigenesis. Here, we showed that the nuclear matrix protein nuclear restricted protein in brain (NRP/B) was colocalized and interacted with NF-E2-related factor 2 (Nrf2). During oxidative stress response, NRP/B expression and its interaction with Nrf2 were upregulated in SH-SY5Y cells. Association of NRP/B with Nrf2 was crucial for NAD(P)H:quinone oxidoreductase 1 (NQO1) expression. NRP/B was localized predominantly in the nucleus of normal brain cells, whereas in primary brain tumors NRP/B was almost exclusively contained in the cytoplasm. In addition, unlike wild-type NRP/B, the expression of NRP/B mutants isolated from primary brain tumors was found in the cytoplasm, and these mutants failed to induce Nrf2-dependent NQO1 transcription. Thus, NRP/B mutations and their altered localization resulted in changes in NRP/B function and deregulation of Nrf2-dependent NQO1 activation in brain tumors. This study provides insights into the mechanism by which the NRP/B modulates Nrf2-dependent NQO1 induction in cellular protection against ROS in brain tumors.Oncogene (2009) 28, 378–389; doi:10.1038/onc.2008.396; published online 3 November 2008 [ABSTRACT FROM AUTHOR]

Lateral loading of the pelvis occurs for both vehicle occupants struck during side impacts as well as pedestrians. This research investigated the load distribution through the anterior (i.e. pubic symphysis) and posterior (i.e. sacrum) aspects of the pelvis for both acetabular and iliac loading. Sixteen male post-mortem human surrogate pelves were tested in quasi-static (n = 4) anddynamic (n = 12) conditions. On the basis of finite element model simulations of a pedestrian being struck at 40 km/hr, a velocity profile for the dynamic tests was prescribed that began at rest (v = 0 m/s) and then achieved apeak velocity of the struck pelvis moving relative to the midline at 4.5 m/s. The average anterior load at fracture from a high - rate acetabulumimp act was 1911 ± 929 N compared to the posterior load averaging 1022 ± 630 N. The average anterior load at fracture from a high - rate iliumimpact was 418 ± 388 N compared to the posterior load averaging 3107 ± 1473 N. [ABSTRACT FROM AUTHOR]

The hypothesis that muscle tension protects the spine from injuries in helicopter scenarios was tested using a finite-element model of the human head and neck. It was compared with cadaver crash sled experiment with good correlation. Then, simulations were performed with a sinusoidal velocity (5-22 G) applied at T1 60° to the horizontal plane. The model with relaxed muscle activation had delayed and decreased peak head rotation compared with passive properties only. Full muscle activation decreased the injury risk for the 13.5-22 G impacts. A sensitivity study of the impact angle showed a very slight variation of the resulting neck flexion, and 1° change affected all ligament injury predictions less than 4%. Finally, simulations with helmets resulted in increased ligament and disc strains with increasing helmet mass and with an anterior or inferior shift of the centre of gravity. It is concluded that the hypothesis seems to hold. [ABSTRACT FROM AUTHOR]

Bioassays for insecticide resistance in adult mosquitoes were conducted on samples of Anopheles gambiae Giles s.l. (Diptera: Culicidae) species collected as larvae from breeding sites in the lower Shire Valley, Malawi. The results indicate full susceptibility to permethrin, deltamethrin and malathion, but reduced susceptibility to DDT in one sample from Thom (LT50 of 8.39 min for females and 25.09 min for males). Polymerase chain reaction-based species identification of the mosquitoes assayed revealed a mixture of Anopheles arabiensis Patton and Anopheles quadriannulatus (Theobold). The LT50 did not differ significantly between species. Genotyping of the L1014F and L1014S kdr alleles showed all mosquito specimens to be homozygous wild type; thus the reduced susceptibility detected is not attributable to target site insensitivity and instead is likely to be metabolic in nature. Anopheles quadriannulatus is characteristically zoophagic and exophilic. Indeed, of 82 Anopheles collected through knockdown collections within dwellings, only one was An. quadriannulatus and the rest were An. arabiensis. They are unlikely, therefore, to have been exposed to selection pressure arising from insecticide-treated net usage or to DDT indoor residual spraying. Therefore, it is suggested that this example of reduced susceptibility to DDT in An. quadriannulatus reflects selection in the larval stages. [ABSTRACT FROM AUTHOR]

Aims: Comparison of biochemical vs molecular methods for identification of microbial populations associated with failed loggerhead turtle eggs. Methods and Results: Two biochemical (API and Microgen) and one molecular methods (16s rRNA analysis) were compared in the areas of cost, identification, corroboration of data with other methods, ease of use, resources and software. The molecular method was costly and identified only 66% of the isolates tested compared with 74% for API. A 74% discrepancy in identifications occurred between API and 16s rRNA analysis. The two biochemical methods were comparable in cost, but Microgen was easier to use and yielded the lowest discrepancy among identifications (29%) when compared with both API 20 enteric (API 20E) and API 20 nonenteric (API 20NE) combined. A comparison of API 20E and API 20NE indicated an 83% discrepancy between the two methods. Conclusions: The Microgen identification system appears to be better suited than API or 16s rRNA analysis for identification of environmental isolates associated with failed loggerhead eggs. Significance and Impact of the Study: Most identification methods are not intended for use with environmental isolates. A comparison of identification systems would provide better options for identifying environmental bacteria for ecological studies. [ABSTRACT FROM AUTHOR]

Schizophrenia (SC) and bipolar disorder (BP) share many clinical features, among them psychosis. We previously identified a putative gene locus for psychosis on chromosome 18p in a sample from the Central Valley of Costa Rica (CVCR) population. The present study replicated the association to a specific allele of microsatellite marker D18S63 on 18p11.3, using a newly collected sample from the CVCR. A combined analysis of both samples, plus additional subjects, showed that this specific allele on D18S63, which lies within an intron on the TGFB-induced factor (TGIF) gene, is strongly associated (P-value=0.0005) with psychosis. Eleven additional SNP markers, spanning five genes in the region, were analyzed in the combined sample from the CVCR. Only the four SNPs within the TGIF gene were in strong linkage disequilibrium with D18S63 (D′=1.00). A specific haplotype for all five markers within the TGIF gene showed evidence of association (P-value=0.011) to psychosis. A second, distinct haplotype, containing a newly identified nonsynonymous polymorphism in exon 5 of the TGIF gene, showed a nonsignificant trend towards association to psychosis (P-value=0.077). TGIF is involved in neurodevelopment, neuron survival and controls the expression of dopamine receptors. Altogether, our results point to the possible involvement of TGIF in the pathophysiology of psychotic disorders in the CVCR population.Molecular Psychiatry (2007) 12, 1033–1041; doi:10.1038/sj.mp.4001997; published online 17 April 2007 [ABSTRACT FROM AUTHOR]

Highly significant changes were found in digenean metacercariae infected gills of killifish Fundulus heteroclitus with respect to gill abnormalities. Gills infected with >1000 metacercariae exhibited up to 42 additional gill branches per fish when compared to less parasitized conspecifics. A strong positive correlation was found between abnormal gill morphology (number of branches) and the number of endoparasites present. [ABSTRACT FROM AUTHOR]

In this paper we question the validity of factitious disorder as a meaningful psychiatric diagnosis. When the diagnosis is used there is often the assumption that the person engaging in the 'deception' is not lying in the traditional sense of being deliberately misleading. Moreover, little is known about the aetiology or psychopathology underlying factitious disorder, and the legitimacy of deception as a mental disorder has been questioned. It is argued that while illness deception may be more common that hitherto assumed, factitious disorder as a distinct type of psychiatric disorder is conceptually flawed, diagnostically impractical and clinically unhelpful and should be dropped from existing nosologies. [ABSTRACT FROM AUTHOR]

Copyright of Genome is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: This study used the population of the Central Valley of Costa Rica (CVCR) and phenotyping strategies alternative to DSMIV classifications to investigate the association of neuregulin 1 with schizophrenia. Method: Using 134 family trios with a history of psychosis, we genotyped six of the seven markers originally identified to be associated with schizophrenia in Iceland. Results: The neuregulin Icelandic haplotype was not associated with schizophrenia in the CVCR population. However, a novel haplotype was found to be overrepresented in subjects with functional psychosis (global P-value > 0.05). Stratification of the sample by history of mania suggests that this haplotype may be preferentially over-transmitted to persons with a history of manic psychosis. Conclusion: These results suggest that the neuregulin 1 gene is unlikely to play a major role in predisposing to schizophrenia in the CVCR. Further studies in the CVCR and other Latin American populations should be performed in order to corroborate these findings. [ABSTRACT FROM AUTHOR]

In the meson exchange model of weak nucleon-nucleon (NN) interactions, the exchange of virtual mesons between the nucleons is parameterized by a set of weak meson exchange amplitudes. The strengths of these amplitudes from theoretical calculations are not well known, and experimental measurements of parity-violating (PV) observables in different nuclear systems have not constrained their values. Transversely polarized cold neutrons traveling through liquid helium experience a PV spin rotation due to the weak interaction with an angle proportional to a linear combination of these weak meson exchange amplitudes. A measurement of the PV neutron spin rotation in helium (φPV (n, α)) would provide information about the relative strengths of the weak meson exchange amplitudes, and with the longitudinal analyzing power measurement in the p + α system, allow the first comparison between isospin mirror systems in weak NN interaction. An earlier experiment performed at NIST obtained a result consistent with zero: φPV (n, α) = (8.0 ± 14(stat) ± 2.2(syst)) x 10-7 rad / m[1]. We describe a modified apparatus using a superfluid helium target to increase statistics and reduce systematic effects in an effort to reach a sensitivity goal of 10-7 rad/m. [ABSTRACT FROM AUTHOR]

This study audited 25 patients (21 female) from Oxfordshire who had been referred to either the liaison psychiatry or the neurological disability service between 1992 and 1998, reported a Barthel activities of daily living index score < 20 or a global assessment of functioning score of < or = 30, and had no pathology to explain their neurological disability. Levels of motor impairment, disability, mood, and cognitive status were assessed using standardised scales, and all patients were assigned a psychiatric diagnosis according to the International classification of diseases, 10th revision. Of the 25 patients, 13 had a motor conversion disorder, 8 had diverse somatoform disorders, and 3 had chronic fatigue syndrome. Nine had extensive previous contact with psychiatric services and 11 had experienced physical or sexual abuse. In 6 patients cessation of repeated self harm was closely associated with the onset of wheelchair use. Seven were receiving treatment for depression. The commonest putative diagnoses were multiple sclerosis (6) and epilepsy (5). Twelve were unable to walk and 20 owned a wheelchair but only 3 had formal care packages. The mean (SD) Barthel score was 14.1 (3.3) and the mean (SD) Frenchay activity index score was 12.9 (7.5). All were unemployed and receiving a disability living allowance, and some had benefits of up to pound 1815 a month. This small but significant group of disabled patients had a variety of psychiatric and neurological diagnoses and used considerable health care resources. [ABSTRACT FROM AUTHOR]

Objective: To describe the demographic and clinical characteristics of consecutive referrals to an out-patient liaison psychiatry clinic in a large university hospital in the UK. Method: We studied 900 patients using a standardized proforma. Assessments of functional capacity were made using the Global Assessment of Functioning (GAF) scale, and each patient was assigned a psychiatric diagnosis using ICD-10 criteria. Results: Four of five of all referrals presented with somatic complaints, and 41% had a concurrent physical illness. The most common psychiatric diagnoses were somatoform disorders (55%) and neurasthenia (11%). Although more than half (59%) had no previous psychiatric history, a surprisingly high number (35%) had significant functional impairment (scores of < 50 on the GAF scale). The lack of adequate psychological treatment services often provided a barrier to optimal management of some of the more disabled patients. Conclusion: The general hospital liaison psychiatry clinic provides an acceptable setting in which to assess and manage patients referred from non-psychiatric colleagues. [ABSTRACT FROM AUTHOR]

Background: Somatoform disorders have few peers in terms of personal morbidity and cost to the health service, yet many psychiatrists train without any experience of them.Aims: To review the prevalence, disability and economic burden of somatoform disorders, and to explore the reasons why they are neglected by psychiatrists.Method: A selective review of the key literature.Results: Psychiatrists' current preoccupation with so-called 'serious mental illness' gives somatoform disorders low priority. Some health planners have erroneously equated severity with diagnosis rather than level of need and disability. As a consequence the development of psychiatric services has been neglected.Conclusions: Greater recognition of the importance of somatoform disorders will only occur if high quality research and teaching receive priority, and if the Royal Colleges continue to press for increasing public awareness of their importance. Services should be driven by clinical need rather than diagnosis. [ABSTRACT FROM AUTHOR]

We studied temperature stability in 22 infants of birthweight less than 1500 g in the first four days of life. Infants were nursed in incubators using either air mode control or skin temperature servo control. Data were collected continuously using a computer linked monitoring system. Skin temperature control resulted in a less stable thermal environment than air mode control. Increased thermal stability in the incubator on air mode control may well be beneficial, particularly to sick, very low birthweight infants. [ABSTRACT FROM AUTHOR]

Twenty-five women with somatisation disorder (SD) were compared with matched patient controls for the presence of personality disorders. Personality was assessed with the Personality Assessment Schedule (PAS). Interviewers were unaware of the patients' diagnoses. All controls had DSM-III-R axis I diagnoses of depressive or anxiety disorders. The prevalence of personality disorders among patients with somatisation disorder was 72% compared with 36% among controls. Certain personality disorders, including passive-dependent, histrionic, and sensitive-aggressive, occurred significantly more often in the SD patients than controls. [ABSTRACT FROM AUTHOR]

A postal questionnaire was sent to 195 senior British psychiatrists who were asked about their attitudes towards the DSM-III-R diagnosis of somatisation disorder (SD) and the ICD-10 diagnosis of multiple somatisation disorder. Of the 148 respondents, 98 (66%) had experience of liaison psychiatry, and these psychiatrists used the diagnosis significantly more often than those without liaison sessions. More than half the respondents perceived SD as both a personality disorder and a mental state disorder, although 27% thought that patients with SD had an undiagnosed physical disease. The marked discrepancy between British and North American psychiatrists in diagnostic practices was perceived to be a consequence of both the difference in health care systems and the interest shown in the disorder by North American psychiatrists, rather than a reflection of genuine differences in prevalence. [ABSTRACT FROM AUTHOR]

'Somatisation' is a process in which there is inappropriate focus on physical symptoms and psychosocial problems are denied. In some patients this process becomes chronic (in excess of six months). Special skills and strategies are required by non-psychiatrists to manage these patients, for whom the acceptance of psychiatric treatment should be facilitated. When taking the history, doctors should be aware of psychosocial cues; thereafter they should be consistent and unambiguous in their management. An agenda should be set early on, with limits on investigations. Failure to manage this group of patients is costly, and further intervention studies are required not only to reduce health service and other costs, but also to relieve the non-monetary burden of physical and psychosocial disability on patients and their relatives. [ABSTRACT FROM AUTHOR]

Anxiety states sometimes lead to hyperventilation (HV) which may, in turn, give rise to a variety of physical symptoms. One way in which HV may present is with unilateral somatosensory symptoms, often left-sided. We report nine such cases. The mechanisms of lateralisation was examined using EEG and bilateral somatosensory evoked potentials which were carried out before and after HV. No difference in conduction velocity was found between affected and unaffected arms, but non-specific abnormalities were frequently noted in the EEGs. The results support the role of a central rather than a peripheral mechanism in the production of unilateral symptoms in HV. [ABSTRACT FROM AUTHOR]