Long-term safety of brazikumab in the open-label period of a randomized phase 2a study of patients with Crohn's disease

BACKGROUND

Short-term efficacy and safety of brazikumab (MEDI2070), a human monoclonal antibody and anti-p19 subunit inhibitor of interleukin-23, was demonstrated in a phase 2a trial in patients with moderate-to-severe active Crohn's disease (CD). We report brazikumab long-term safety and tolerability from the open-label period of this phase 2a study.

METHODS

Patients who completed the 12-week, double-blind induction period were eligible for inclusion in an open-label period where all patients received subcutaneous brazikumab (210 mg) every 4 weeks for 100 weeks. Patients had moderate-to-severe active CD and had failed or were intolerant to ≥ 1 anti-tumour necrosis factor alpha (TNFα) agent. Safety assessments included treatment-emergent adverse events (TEAEs); further assessments were pharmacokinetics and immunogenicity.

RESULTS

Of the 104 patients who entered the open-label period, 57 (54.8%) continued to the end of the open-label period and 47 (45.2%) discontinued brazikumab. The most common reasons for discontinuation were lack of response (14.4%), patient decision (12.5%), and TEAEs (11.5%). In total, 44 (84.6%) in the group switching from placebo to brazikumab (placebo/brazikumab) and 43 (82.7%) in the group continuing brazikumab (brazikumab/brazikumab) experienced 1 or more TEAEs. Most TEAEs were mild-to-moderate in severity. Common TEAEs included nasopharyngitis and headache. Numbers of treatment-emergent serious adverse events (TESAEs) were similar between groups. Infections occurred in 40.4% of patients in the placebo/brazikumab group and 50% in the brazikumab/brazikumab group. There were 5 TESAEs of infection, none of which were opportunistic. No major adverse cardiac events, malignancies, or deaths were reported.

CONCLUSIONS

Brazikumab was well tolerated with an acceptable safety profile over a 100-week period in patients with moderate-to-severe active CD who failed or were intolerant to 1 or more anti-TNFα agents.

TRIAL REGISTRATION

NCT01714726; registered October 26, 2012.

A randomised, double-blind, placebo-controlled study of the LAG-3-depleting monoclonal antibody GSK2831781 in patients with active ulcerative colitis

BACKGROUND

Selective depletion of T cells expressing LAG-3, an immune checkpoint receptor that is upregulated on activated T cells, has been investigated in pre-clinical models as a potential therapeutic approach in inflammatory and autoimmune diseases where activated T cells are implicated.

AIMS

GSK2831781, a depleting monoclonal antibody that specifically binds LAG-3 proteins, may deplete activated LAG-3⁺ cells in ulcerative colitis (UC).

METHODS

Patients with moderate to severe UC were randomised to GSK2831781 or placebo. Safety, tolerability, efficacy, pharmacokinetics and pharmacodynamics of GSK2831781 were evaluated.

RESULTS

One hundred four participants across all dose levels were randomised prior to an interim analysis indicating efficacy futility criteria had been met. Efficacy results focus on the double-blind induction phase of the study (GSK2831781 450 mg intravenously [IV], N = 48; placebo, N = 27). Median change from baseline (95% credible interval [CrI]) in complete Mayo score was similar between groups (GSK2831781 450 mg IV: -1.4 [-2.2, -0.7]; placebo: -1.4 [-2.4, -0.5]). Response rates for endoscopic improvement favoured placebo. Clinical remission rates were similar between groups. In the 450-mg IV group, 14 (29%) participants had an adverse event of UC versus 1 (4%) with placebo. LAG-3⁺ cells were depleted to 51% of baseline in blood; however, there was no reduction in LAG-3⁺ cells in the colonic mucosa. Transcriptomic analysis of colon biopsies showed no difference between groups.

CONCLUSION

Despite evidence of target cell depletion in blood, GSK2831781 failed to reduce inflammation in the colonic mucosa suggesting no pharmacological effect. The study was terminated early (NCT03893565).

P3131Evolution of subclinical rheumatic heart disease: a multi-centre retrospective cohort study

Background

Screening echocardiography (echo) detects subclinical rheumatic heart disease (RHD) which is categorised as definite or borderline. The natural history of subclinical RHD is not known. Follow up single centre studies have included a relatively small number of participants, and have shown variable progression rates.

Aim

To determine incidence of and factors associated with progression and regression among a cohort of children with baseline subclinical RHD across multiple countries and regions.

Methods

This is a retrospective cohort study of RHD evolution in children with subclinical RHD. Study sites were Australia, Fiji, Malawi, New Zealand, and Uganda. Progression or regression was determined from echos obtained at baseline and most recent follow-up. Factors associated with echo progression or regression were identified using multivariable logistic regression.

Results

482 participants (131 with definite, 351 with borderline subclinical RHD) from 5 countries were included (mean age 11.5 years, range 5–19 years). Mean follow up was 3.4 yrs (range 0.4–9.5 yrs). Of 482 participating children, 204 (42%) regressed. Among 131 children with definite lesions, 48 (37%) regressed to borderline or normal, and 83 (63%) remained definite. Among 351 children with borderline lesions, 39 (11.1%) progressed, 156 (44.4%) remained borderline, and 156 (44.4%) regressed to normal. World Heart Federation defines subcategories based on characteristics of affected valves. By subcategory, children with definite C (pathological aortic regurgitation and 2 morphologic characteristics of the aortic valve) and borderline A (at least 2 morphologic features of the mitral valve without pathologic mitral regurgitation or stenosis) were less likely to regress, and borderline A was more likely to progress. In univariable analysis, good adherence (>80%) to penicillin prophylaxis (BPG) was associated with more regression among all patients (definite + borderline) (OR 1.9, CI 1, 3.5; p=0.04) but this association did not remain significant after adjustment. With multivariable analysis, borderlines prescribed BPG was the only factor related to progression from borderline to definite (OR 4.1, CI 1.8, 9.3, p<0.01).

Conclusion

This is the largest reported subclinical RHD cohort followed to report outcomes. 42% of definite RHD regressed with subtype C more likely to regress. 11% of borderline RHD progressed. Borderline A was more likely to progress and less likely to regress. We have also identified that being prescribed BPG is associated with borderline progression. This is likely because children with more advanced borderline disease may be more likely to be prescribed BPG. This study highlights that RHD evolution is variable out to 3–4 years post echo detection. While borderline disease is likely, in some cases, to reflect the earliest change of RHD, how this should be monitored and whether it should be treated with BPG should be a priority for future prospective evaluation.

Advanced schemes for underdense plasma photocathode wakefield accelerators: pathways towards ultrahigh brightness electron beams

The 'Trojan Horse' underdense plasma photocathode scheme applied to electron beam-driven plasma wakefield acceleration has opened up a path which promises high controllability and tunability and to reach extremely good quality as regards emittance and five-dimensional beam brightness. This combination has the potential to improve the state-of-the-art in accelerator technology significantly. In this paper, we review the basic concepts of the Trojan Horse scheme and present advanced methods for tailoring both the injector laser pulses and the witness electron bunches and combine them with the Trojan Horse scheme. These new approaches will further enhance the beam qualities, such as transverse emittance and longitudinal energy spread, and may allow, for the first time, to produce ultrahigh six-dimensional brightness electron bunches, which is a necessary requirement for driving advanced radiation sources. This article is part of the Theo Murphy meeting issue 'Directions in particle beam-driven plasma wakefield acceleration'.

Laser-plasma-based Space Radiation Reproduction in the Laboratory

Space radiation is a great danger to electronics and astronauts onboard space vessels. The spectral flux of space electrons, protons and ions for example in the radiation belts is inherently broadband, but this is a feature hard to mimic with conventional radiation sources. Using laser-plasma-accelerators, we reproduced relativistic, broadband radiation belt flux in the laboratory, and used this man-made space radiation to test the radiation hardness of space electronics. Such close mimicking of space radiation in the lab builds on the inherent ability of laser-plasma-accelerators to directly produce broadband Maxwellian-type particle flux, akin to conditions in space. In combination with the established sources, utilisation of the growing number of ever more potent laser-plasma-accelerator facilities worldwide as complementary space radiation sources can help alleviate the shortage of available beamtime and may allow for development of advanced test procedures, paving the way towards higher reliability of space missions.

Transforming Growth Factor Beta Gene Signatures are Spatially Enriched in Keloid Tissue Biopsies and Ex vivo-Cultured Keloid Fibroblasts

The keloid lesion is recognised as a spatially heterogeneous mass both in cellular and acellular composition and biological activity. Here, we have utilised a bioinformatic approach to determine whether this spatial heterogeneity is also evident at the molecular level and to identify key upstream regulators of signalling pathways enriched in the lesion in a spatially-restricted manner. Differentially expressed genes (20% change, p < 0.05) obtained from microarray datasets derived from whole keloid biopsies and ex vivo-cultured keloid fibroblasts, both from distinct regions of the keloid lesion (leading edge, centre, and top) have been analysed to show that the TGFβ family plays a significant but spatially dependent role in regulation of keloid gene expression. Furthermore, we have identified additional upstream signalling molecules involved in driving keloid biology and provide information on therapeutic targets whose modulation might be expected to lead to significant therapeutic efficacy.

Howzat?! Why is there an Over-representation of Left-handed Bowlers in Professional Cricket in the UK?

An analysis of the bowling action of professional cricketers in the UK for four seasons between 1981 and 1991 shows there to be a significant association between handedness and bowling style (seam or spin bowling). Furthermore, there is a significantly higher number of left-handed spin bowlers than would be predicted from the general population, but not left-handed seam bowlers. As the technical differences between left- and right-handed orthodox spin bowlers are much greater than those between left- and right-handed seam bowlers, these data are consistent with the view that the over-representation of left-handed bowlers reported by Wood and Aggleton (1989) is due to strategic rather than neuropsychological factors.

Venous thromboembolism--prophylactic and therapeutic practice guideline

BACKGROUND

Pharmacological prophylactic anticoagulation in many countries, including South Africa, is under-prescribed, which unfortunately results in unacceptable morbidity and mortality in a substantial number of patients.

METHOD

The Southern African Society of Thrombosis and Haemostasis reviewed the available literature as well as guidelines from other societies. Specialties represented on the committees included anaesthetics, cardiology, clinical haematology, critical care, gynaecology, haematopathology, internal medicine, neurology, orthopaedic surgery, pulmonology and vascular surgery. A draft document was produced, which was revised by consensus agreement. To avoid local bias, the guidelines were adjudicated by recognised independent international external experts. RESULTS AND CONCLUSION. A concise, practical guideline for thrombo-prophylaxis and treatment in medical and surgical patients has been produced for South African conditions. These guidelines will hopefully lead to improved anticoagulation practice in this country, which we believe will directly benefit patient outcomes.

Cytokines, matrix metalloproteases, angiogenic and growth factors in tears of normal subjects and vernal keratoconjunctivitis patients

BACKGROUND

To detect the presence of multiple mediators and growth factors in tears of vernal keratoconjunctivitis (VKC) patients with active disease using stationary phase antibody arrays.

METHODS

Tears were collected from 12 normal subjects (CT) and 24 active VKC patients. Tears were centrifuged and successively probed using three microwell plate arrays specific for: (i) cytokines: interleukin (IL)-2, IL-4, IL-5, IL-8, IL-10, IL-12, IL-13, interferon-gamma and tumour necrosis factor-alpha; (ii) growth factors: basic fibroblast growth factor (bFGF), platelet-derived growth factor, thrombopoietin, angiopoietin-2, vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), keratocyte growth factor, tissue inhibitor of metalloprotease (TIMP)-1 and heparin-binding epithelial growth factor (HB-EGF) and (iii) matrix metalloprotease (MMP)-1, MMP-2, MMP-3, MMP-8, MMP-9, MMP-10, MMP-13, TIMP-1 and TIMP-2.

RESULTS

Interleukin-8 signals were detected in all CT and highly detected in all VKC samples. The Th2-type cytokines, IL-4, IL-5 and IL-10 were detected only in tears of VKC patients. Signals for bFGF, HB-EGF, VEGF and HGF were detected in 41-87% of VKC samples and in few CT samples. Only TIMP-1 and TIMP-2 were found in all normal and patient tear samples, whereas MMP-1, MMP-2, MMP-3, MMP-9 and MMP-10 were highly present in all VKC samples.

CONCLUSIONS

Stationary phase antibody array methodology was useful for the screening of various cytokines, growth factors and MMPs in tears. These analyses identified in tears of VKC patients previously unreported factors including MMP-3 and MMP-10 and multiple proteases, growth factors and cytokines, which may all play an important role in the pathogenesis of conjunctival inflammation.

Inhibitors of protein kinase C (PKC) prevent activated transcription: role of events downstream of NF-kappaB DNA binding

In pulmonary A549 cells, the protein kinase C (PKC) inhibitor, Ro 31-8220, and the phosphotidylcholine-specific phospholipase C inhibitor, D609, prevent NF-kappaB-dependent transcription, yet NF-kappaB DNA binding is unaffected (Bergmann, M., Hart, L., Lindsay, M., Barnes, P. J., and Newton, R. (1998) J. Biol. Chem. 273, 6607-6610). We now show that this effect also occurs in BEAS-2B bronchial epithelial cells as well as with other PKC inhibitors (Gö 6976, GF109203X, and calphostin C) in A549 cells. Similarly, phorbol ester, a diacylglycerol mimetic, activates NF-kappaB-dependent transcription and potentiates tumor necrosis factor alpha (TNFalpha)-induced NF-kappaB-dependent transcription, yet unlike TNFalpha, poorly activates IkappaB kinase (IKK) activity, IkappaBalpha degradation, or NF-kappaB DNA binding in both A549 and BEAS-2B cells. As phorbol ester-induced NF-kappaB-dependent transcription was relatively insensitive to the proteasome inhibitor, MG-132, PKC may affect NF-kappaB-dependent transcription via mechanisms other than the core IKK-IkappaB pathway. This is supported by Gal4 one hybrid analysis of p65/RelA transactivation, which was potentiated by TNFalpha and phorbol ester and was inhibited by Ro 31-8220 and D609. Additionally, a number of PKC isoforms, particularly the novel isoform PKCepsilon, induced p65/RelA transactivation. Phosphorylation of p65/RelA and cAMP-responsive element-binding protein (CREB)-binding protein (CBP) was increased by TNFalpha treatment and, in the case of CBP, was prevented by Ro 31-8220 or D609. However, p65/RelA-CBP interactions were unaffected by either compound. As this effect was not limited to NF-kappaB, but was a more general feature of inducible gene transcription, we suggest PKC isoforms may provide a point of intervention in diseases such as inflammation, or cancer, where activated gene expression is prominent.

Thought suppression, intelligence, and working memory capacity

The importance of individual differences in intelligence and working memory capacity in predicting the ability to intentionally suppress thoughts was investigated. Sixty participants completed a thought suppression task, and measures of working memory capacity (OSPAN), fluid intelligence (Raven's Matrices), and crystallised intelligence (the National Adult Reading Test). As predicted, the results indicated that more effective thought suppression was independently related to higher working memory capacity and greater fluid intelligence, but was unrelated to crystallised intelligence. The findings have theoretical implications for understanding the mechanisms underlying a failure to inhibit unwanted intrusions and clinical implications for disorders involving high levels of intrusive thoughts and memories.

Host-defense mechanism of the ocular surfaces

The defense of the ocular surfaces presents an unique challenge in that not only must integrity be maintained against microbial, inflammatory and physical assault, but it must be done while minimizing the risk of loss of corneal transparency. This puts severe limitations on the degree to which scarring or neovascularization can occur in the cornea secondary to any infectious, inflammatory, immunological or wound healing process. Moreover, this defense system must be equally effective under two extremes of conditions: those found in the open eye and the closed eye environments. It is our contention that these constraints have resulted in the evolution of a highly complex fail-safe defense system that utilizes distinctly different strategies in open and closed eye conditions. The extraordinary effectiveness of this system is evidenced by the fact that despite continued exposure to a microbe rich environment, the external ocular surfaces maintain a very low microbial titer and are highly resistant to breaching by all but a few pathogens. It is the intent of this review to provide a working model of this defense system as it operates under both open and closed eye conditions, to provide evidence in support of this model as well as highlight some of the many areas of uncertainty.

Effect of external ocular surgery and mode of post-operative care on plasminogen, plasmin, angiostatins and alpha(2)-macroglobulin in tears

PURPOSE

To determine whether corneal surgery and the mode of post-surgical treatment influence the distribution of plasminogen, plasmin, angiostatins and alpha(2)-macrogobulin in tear fluid.

METHODS

Subjects underwent either photorefractive keratectomy (PRK), insertion of intra-stromal corneal rings (ICR), or cataract ablation followed by insertion of an intra-ocular lens (IOL). Post-surgical treatment consisted of prophylactic use of antibiotic and anti-inflammatory agents followed either by patching for 24 hours, or covering the wounded cornea with a bandage soft contact lens. Open eye tear fluid (OTF) was obtained prior to surgery and 10 minutes after patch removal or 24 hours after surgery and thereafter with the bandage lens still in place. After centrifugation, supernatants and controls were western blot analyzed using a protocol designed to allow the simultaneous semi- quantitative detection of alpha2-macroglobulin, plasminogen, plasmin, angiostatins and interleukin-8 (IL-8).

RESULTS

No obvious differences were apparent in OTF recovered from contralateral control eyes compared to the surgical eyes in individuals who underwent PRK surgery and whose eyes were covered with a bandage contact lens. In contrast, OTF samples recovered 10 minutes after patch removal from all individuals contained elevated levels of alpha2-macroglobulin and a diverse mixture of elevated levels of plasminogen/plasmin, angiostatins and possibly a plasmin-a1-antiplasmin complex. All of these changes were seen, albeit to a lesser extent, in the patched control OTF samples. IL-8 could not be detected in any sample. The composition of the tear film returned to near normal on subsequent sampling 24 hours after patch removal.

CONCLUSIONS

Patching results in a marked increase in the concentration of various proteins which could modulate inflammation and wound healing.

Towards a closed eye model of the pre-ocular tear layer

Although the tear film has been extensively studied as it exists in the open eye state, until recently very little was known as to what happens to the tear film on eye closure. Recent studies have shown that eye closure results in a profound change in the composition, origins, turnover and physiological functions of the tear film. These changes include a shift from an inducible, neurologically controlled, lacrimal secretion containing among other proteins primarily lysozyme, lactoferrin and tear specific lipocalin, to a much slower, constitutive-type of secretion, composed almost exclusively of sIgA. This change is accompanied by the build-up of sialoglycoproteins of epithelial and goblet cell origin, the build-up and activation of complement and the build-up of serum proteins. In addition, various cytokines and proinflammatory mediators accumulate, including some which are potent inducers of angiogenesis and leukochemotaxis. The closed eye also exhibits the recruitment and activation of massive numbers of PMN cells. This results in a stagnant, closed eye layer, which is extremely rich in reactive complement products, PMN cell proteases including protease-3, elastase, capthepsin G, MMP-9 and urokinase. We have postulated that this shift represents a fundamental change in host-defense strategies from a passive-barrier defense to an active immune, inflammatory, phagocyte-mediated process and that this shift is necessitated in order to protect the cornea from entrapped microorganisms. Studies have shown that autologous cell damage is avoided in closed eye tear fluid, by the accumulation of several modulators of complement activation, which shift activation towards opsonization of entrapped microorganisms and the build-up of a wide array of antiproteases. Some of the latter are likely to arise from the ocular surface tissues. Corneal neovascularization may be avoided in part by the build-up of alpha2-macroglobulin and the conversion of plasminogen to angiostatin. It is highly probable that other bioactive protein fragments are produced in the closed eye, which contribute to homeostasis. Areas of future study are indicated.

The Berkeley Drosophila Genome Project gene disruption project: Single P-element insertions mutating 25% of vital Drosophila genes

A fundamental goal of genetics and functional genomics is to identify and mutate every gene in model organisms such as Drosophila melanogaster. The Berkeley Drosophila Genome Project (BDGP) gene disruption project generates single P-element insertion strains that each mutate unique genomic open reading frames. Such strains strongly facilitate further genetic and molecular studies of the disrupted loci, but it has remained unclear if P elements can be used to mutate all Drosophila genes. We now report that the primary collection has grown to contain 1045 strains that disrupt more than 25% of the estimated 3600 Drosophila genes that are essential for adult viability. Of these P insertions, 67% have been verified by genetic tests to cause the associated recessive mutant phenotypes, and the validity of most of the remaining lines is predicted on statistical grounds. Sequences flanking >920 insertions have been determined to exactly position them in the genome and to identify 376 potentially affected transcripts from collections of EST sequences. Strains in the BDGP collection are available from the Bloomington Stock Center and have already assisted the research community in characterizing >250 Drosophila genes. The likely identity of 131 additional genes in the collection is reported here. Our results show that Drosophila genes have a wide range of sensitivity to inactivation by P elements, and provide a rationale for greatly expanding the BDGP primary collection based entirely on insertion site sequencing. We predict that this approach can bring >85% of all Drosophila open reading frames under experimental control.

Lactation-associated and prolactin-responsive changes in protein synthesis in mouse mammary cells

Lactational function in the mammary epithelial cell is subject to complex regulation, most probably involving multiple extracellular and intracellular proteins that act at any of a number of levels. Although some of these proteins have been identified it is likely that additional controllers of lactation exist, but have yet to be discovered. In an effort to identify such proteins, a search was made for non-milk lactation-associated or prolactin-responsive proteins in primary mouse mammary epithelial cells and the mouse mammary epithelial cell line, COMMA-D using two-dimensional electrophoresis on large-format gels. These analyses revealed 12 proteins whose rate of synthesis was dependent on lactation state or on response to prolactin. Two of these (p77 and p63) were lactation-associated in primary cells and prolactin-responsive in COMMA-D cells. These two proteins were identified by amino acid sequencing as glucose-regulated protein 78 (GRP78) and protein disulphide isomerase (PDI). The localization of these proteins in the endoplasmic reticulum and their presence in other secretory cell types and tissues suggests that they have a function in the processing or secretion of milk proteins.

Diurnal variations in tear glycoproteins: evidence for an epithelial origin for the major non-reducible > or = 450 kDa sialoglycoprotein(s)

PURPOSE

To characterize the nature and origin of changes in tear glycoproteins accompanying eye closure.

METHODS

Reflex (R) and overnight closed (C) eye tears collected by capillary tubes were centrifuged with the resulting R pellets (primarily desquamated epithelial cells) and C pellets (primarily PMN and some epithelial cells) extracted in acidic PBS. Extracts and supernatants were separated by size-exclusion HPLC and/or SDS-PAGE. Gels were stained or blotted and immune- or lectin-probed. An HPLC glycoprotein fraction of > or = 450 kDa isolated from all four sources was characterized before and after partial deglycosylation, using antibodies specific to known mucin and carbohydrate epitopes. Immunofluorescence microscopy was carried out on human conjunctiva, using as probe a MAb to salivary mucin specific for a sialyl Lea epitope, which was found to cross-react specifically with the major non-reducible high molecular weight sialoglycoproteins (SGs) in tears. These SGs were immunoprecipitated and blot-probed along with tissue extracts.

RESULTS

R fluid contained minor amounts of numerous glycoproteins, including probably several of inducible lacrimal secretory origin. Results confirmed sIgA as the principal source of the intense reducible glycoprotein bands common to C fluid. Smaller amounts of free secretory component and serum glycoproteins were also visualized. The HPLC fraction (> or = 450 kDa) consisted of four major non-reducible glycoproteins. In R fluid, this fraction (< 1% total protein) consisted primarily of two entities: a 450-500 kDa SG and a larger asialoglycoprotein. The SG accounts for as much as 85% of the total protein in the R pellet extract. C fluid was associated with a selective increase in SGs and a shift in distribution to two SGs > 500 kDa. All SGs exhibited a common antigenicity reacting specifically with the MAb for the sialyl Lea epitope. SGs indistinguishable in size and antigenicity were recovered in epithelial extracts. Immunofluorescence microscopy revealed that reactivity was localized to the epithelial plasma membrane, increasing in intensity from basal to apical cells. Although these SGs exhibited some properties in common with MUC1, immunological and other data suggest a unique SG.

CONCLUSIONS

Tear glycoproteins are derived from four principal sources. In R fluid, an inducible lacrimal secretion predominates. In C fluid, a constitutive sIgA secretion predominates, augmented by a serum exudate and SGs derived at least in part from the epithelium. In R fluid and pellet extracts, the SGs consist primarily of a 450-500 kDa species that is most probably derived from the plasma membrane. Larger antigenically related SGs are prevalent in C fluid.

On the nature of auditory neglect: a reply to Hugdahl and Wester

We respond to the points raised by Hugdahl and Wester (1994) and argue that a definition of auditory neglect must be based not on consideration of lesion location and extension but on a theoretical understanding of the mechanisms held to underlie neglect in the auditory modality. A first requirement is to describe the phenomenon that has to be explained. An ear extinction effect in dichotic listening, even considered along with the site of brain damage, does not provide sufficient justification for the effect to be attributed to "neglect."

Factors affecting the learning of foreign language vocabulary: imagery keyword mediators and phonological short-term memory

In order to investigate the cognitive processes involved in learning Foreign Language (FL) vocabulary, this study evaluates different methods of instruction. It demonstrates that keyword techniques are effective for receptive learning but that repetition is a superior strategy for learning to produce the foreign word. Performance is optimal when learners combine both strategies. The nature of the keyword is crucial--whereas imageable noun keywords promote learning, verb keywords actually impede it. A theoretical analysis of the roles of phonological short-term memory, imagery, and lexical factors in FL vocabulary learning is presented.

"Auditory neglect after right frontal lobe and right pulvinar thalamic lesions": comments on Hugdahl, Wester, and Asbjørnsen (1991) and some preliminary findings

We take issue with the claim recently made in this journal that extinction of left ear input during dichotic, but not monaural, stimulus presentation demonstrates "auditory attentional neglect" (Hugdahl, Wester, & Asbjørnsen, 1991). We also report on a patient suffering from unilateral visual neglect, who shows extinction under dichotic, but not monaural, conditions of stimulus presentation but this is not confined to one ear. Although this patient denies hearing both of two dichotically presented words, he recognizes the extinguished stimulus when given a forced-choice recognition task.

Expression from the adeno-associated virus p5 and p19 promoters is negatively regulated in trans by the rep protein

The leftward two promoters of the adeno-associated virus (AAV) 2 genome were fused to reporter genes, and the constructs were used to transfect HeLa cells. The promoters functioned constitutively but were repressed in trans by the AAV rep gene product(s). The repression was relieved by adenovirus infection. Evidence which indicated an enhancer function for the inverted terminal repeat of the AAV-2 genome was also obtained.

Orientation selectivity of the human visual system as a function of retinal eccentricity and visual hemifield

An adaptation method was used to determine the specificity of orientation-selective channels in the human visual system at different retinal eccentricities (up to 16 deg) in both hemifields of each eye. For a vertical test grating, the elevation in contrast threshold produced by adapting to a high-contrast grating of the same spatial frequency but variable orientation was equated with the contrast levels of a vertical adapting grating that produced equivalent effects (equivalent-contrast transformation). This enabled comparisons to be made between the orientation tuning of the aftereffect at different retinal loci. For the spatial frequency employed (3 cycles deg-1), no systematic change in orientation selectivity was found as a function of either retinal eccentricity or the hemifield (and hence the cerebral hemisphere) stimulated.