Anxiety and error-related brain activity

Error-related negativity (ERN/Ne) is a component of the event-related brain potential (ERP) associated with monitoring action and detecting errors. It is a sharp negative deflection that generally occurs from 50 to 150 ms following response execution and has been associated with anterior cingulate cortex (ACC) activity. An enhanced ERN has been observed in patients with obsessive-compulsive disorder (OCD)--reflecting abnormal ACC activity hypothesized as part of the pathophysiology of OCD. We recently reported that the ERN is also enhanced in a group of college students with OC characteristics. The present study extended these findings by measuring the ERN in college undergraduates who scored high on either the Penn State Worry Questionnaire (PSWQ) or a combined version of the Snake (SNAQ) and Spider (SPQ) Questionnaires. Results indicate that, like OC subjects, subjects who score high on a measure of general anxiety and worry have enhanced error-related brain activity relative to both phobic and non-anxious control subjects. The enhanced ERN was found to generalize beyond OCD within the anxiety spectrum disorders but also shows some specificity within these disorders.     

Immunohistochemical study of the vaginal inflammatory response in experimental trichomoniasis

In the present paper, the acute and subchronical inflammatory processes of the vaginal epithelial were studied in mice experimentally infected with two Trichomonas vaginalis strains of different pathogenicity, by means of histological and immunological methods. There was an increase in the stratified epithelium layers as well as edema produced by the increase of vascularization in the propia submucosa and infiltration of leukocytes. The proliferation of the vaginal epithelium favors the settlement and persistence of the parasitic infection. All of the findings corresponded with signs of a systemic disease being observed in the animals, including significant weight loss and also intestinal invasion. The entire inflammatory process has been corroborated by studies of adhesion molecules such as E-Selectin, VCAM-1 and PECAM-1. A correlation between the time of appearance and the perseverance of the inflammatory process with E-Selectin and VCAM-1 expression was observed, but not with PECAM-1. The strain with a higher pathogenicity was able to invade deep vaginal tissues and thus, parasites could not be detected by vaginal washings. This may be an important cause of diagnosis and treatment failure. Also, by the different localization of trichomonads, it appeared that the battle between host and parasite took place in different areas dependent upon the characteristics of the strain.     

Safety of levocetirizine treatment in young atopic children: An 18-month study

There are more than 40 H(1)-antihistamines available worldwide. Most of these medications have never been optimally studied in prospective, randomized, double-masked, placebo-controlled trials in children. The aim was to perform a long-term study of levocetirizine safety in young atopic children. In the randomized, double-masked Early Prevention of Asthma in Atopic Children Study, 510 atopic children who were age 12-24 months at entry received either levocetirizine 0.125 mg/kg or placebo twice daily for 18 months. Safety was assessed by: reporting of adverse events, numbers of children discontinuing the study because of adverse events, height and body mass measurements, assessment of developmental milestones, and hematology and biochemistry tests. The population evaluated for safety consisted of 255 children given levocetirizine and 255 children given placebo. The treatment groups were similar demographically, and with regard to number of children with: one or more adverse events (levocetirizine, 96.9%; placebo, 95.7%); serious adverse events (levocetirizine, 12.2%; placebo, 14.5%); medication-attributed adverse events (levocetirizine, 5.1%; placebo, 6.3%); and adverse events that led to permanent discontinuation of study medication (levocetirizine, 2.0%; placebo, 1.2%). The most frequent adverse events related to: upper respiratory tract infections, transient gastroenteritis symptoms, or exacerbations of allergic diseases. There were no significant differences between the treatment groups in height, mass, attainment of developmental milestones, and hematology and biochemistry tests. The long-term safety of levocetirizine has been confirmed in young atopic children.     

On the ERN and the significance of errors

The error-related negativity (ERN) is an event-related brain potential observed when subjects commit errors. To examine whether the ERN is sensitive to the value of errors, the motivational significance of errors was manipulated in two experiments. In Experiment 1, low and high monetary value errors were compared to evaluate the effect of trial value on the ERN. In Experiment 2, subjects performed a flanker task both while their performance was being evaluated and during a control condition. Consistent with the notion that the error-detection system is sensitive to the significance of errors, the ERN was significantly larger on high-value trials in Experiment 1 and during evaluation in Experiment 2. There were no corresponding effects on the correct response negativity, and no behavioral differences between conditions were evident in either experiment. These results are discussed in terms of the functional role of the ERN in response monitoring.     

High-resolution computed tomography study of the cranium of a fossil anthropoid primate, Parapithecus grangeri: new insights into the evolutionary history of primate sensory systems

Extant anthropoids have large brains, small olfactory bulbs, and high-acuity vision compared with other primates. The relative timing of the evolution of these characteristics may have important implications for brain evolution. Here computed tomography is used to examine the cranium of a fossil anthropoid, Parapithecus grangeri. It is found that P. grangeri had a relatively small brain compared with living primates. In addition, it had an olfactory bulb in the middle of the range for living primates. Methods for relating optic foramen area and other cranial measurements to acuity are discussed. Multiple regression is used to estimate retinal ganglion cell number in P. grangeri. Given currently available comparative data, P. grangeri seems to have had retinal ganglion cell counts intermediate for living primates, overlapping with the upper end of the range for strepsirrhines and possibly with the lower end for anthropoids.     

Immune responses to mosquito saliva in 14 individuals with acute systemic allergic reactions to mosquito bites

BACKGROUND: Mosquito bite-induced acute systemic allergic reactions are an increasing clinical concern and have not been optimally characterized immunologically. OBJECTIVE: We wanted to study the immunologic basis of these reactions. METHODS: Sera were received from 14 individuals with a history of acute systemic allergic reactions to mosquito bites, defined as the presence of one or more of the following: urticaria, angioedema, wheezing, dyspnea, hypotension, and decrease or loss of consciousness. Ten individuals were from the United States and one each was from Canada, Germany, Japan, and Switzerland. An indirect ELISA was developed to measure specific IgE and IgG antibodies to saliva from 5 common mosquito species with different geographic distributions: Aedes aegypti, Aedes vexans, Aedes albopictus, Anopheles sinensis, and Culex quinquefasciatus. Twenty-nine individuals with negative bite test results from laboratory-reared mosquitoes served as control subjects. RESULTS: Mosquito saliva-specific IgE levels to all 5 species were significantly increased in the individuals with systemic allergic reactions compared with the control subjects ( P < .061 for Aedes vexans and P < .008 for the remaining 4 species). By using the mean of the control subjects plus 1 SD as a cut-off level, 11 individuals had positive results to Aedes albopictus and up to 4 additional species; 3 individuals had positive results to only one species. Saliva-specific IgG levels were not significantly increased in the individuals with systemic allergic reactions compared with levels seen in the control subjects ( P > .05). CONCLUSION: Acute systemic allergic reactions to mosquito bites involve mosquito saliva-specific IgE and can be characterized immunologically. Aedes albopictus is the most common species associated with systemic allergic reactions to mosquito bites.     

Egg-sharing in assisted conception: ethical and practical considerations

The present acute shortage of eggs for donation cannot be overcomeunless adequate guidelines are set to alleviate the anxietiesregarding payments, in cash or kind, to donors. The currentHuman Fertilisation and Embryology Authority (HFEA) guidelinesdo not allow direct payment to donors but accept the provisionof lower cost or free in-vitro fertilization (IVF) treatmentto women in recognition of oocyte donation to anonymous recipients.Egg-sharing achieved in this way enables two infertile couplesto benefit from a single surgical procedure. However, the practicalguidelines related to this approach are ill-defined at the presenttime leading to some justifiable uncertainty. A pilot studywas therefore undertaken in order to establish the place ofegg-sharing in an assisted conception programme. The currentHFEA guidelines on medical screening of patients, counselling,age and rigid anonymity between the donor and recipient werefollowed. The study involved 55 women (25 donors and 30 recipients)in 73 treatment cycles involving fresh and frozen-thawed embryos.Donors were previous IVF patients who, regardless of their abilityto pay, shared their eggs equally with matched anonymous recipients.They paid only for their consultations and tests right up tothe point of being matched with a recipient The sole recipientpaid the cost applicable in egg donation of a single egg collection,although both received embryo transfers. The results indicatethat although the recipients were older than the donors (41.4± 0.9 versus 31.6 ± 0.5 years), and there wasno difference in the mean number of eggs allocated, the percentagefertilization rates, or the mean number of embryos transferred,there were more births per patient amongst recipients than amongstdonors (30 versus 20%). We conclude that providing the donorsare selected carefully, this scheme whereby a sub-fertile donorhelps a sub-fertile recipient is a very constructive way ofsolving the problem of the shortage of eggs for donation. Thereare also the advantages of including a group of women who wouldotherwise be denied treatment Problems related to ‘patientcoercion’ can, in our view, be fully overcome by the applicationof strict common-sense safeguards. The ideal of pure altruismis not without its medical and moral risk. The success of egg-sharingdepends on shared interests and a degree of altruism betweenthe donor, the recipient and the centre. The current HFEA guidelinesshould be applauded for enabling a highly effective conceptof mutual help to develop.     

Sequence and genomic organization of GBV-C: A novel member of the flaviviridae associated with human non-A-E hepatitis

Recently, sequences from a novel virus, termed GB virus C (GBV-C), were identified in serum from several patients with cryptogenic hepatitis. In the present study, the nucleotide sequence of this virus has been extended to near-genome length. GBV-C encodes a putative single large polyprotein in which the structural proteins are positioned at the N-terminal end, with the nonstructural proteins located at the C-terminal end. Amino acid sequence analysis of this large polyprotein reveals the presence of protease, helicase, and replicase motifs. Sequence alignments of the polyprotein followed by phylogenetic analyses suggest that GBV-C is a member of the Flaviviridae, most closely related to the recently described GB virus A. © 1996 Wiley-Liss, Inc.