psudo: Exploring Multi-Channel Biomedical Image Data with Spatially and Perceptually Optimized Pseudocoloring

Over the past century, multichannel fluorescence imaging has been pivotal in myriad scientific breakthroughs by enabling the spatial visualization of proteins within a biological sample. With the shift to digital methods and visualization software, experts can now flexibly pseudocolor and combine image channels, each corresponding to a different protein, to explore their spatial relationships. We thus propose psudo, an interactive system that allows users to create optimal color palettes for multichannel spatial data. In psudo, a novel optimization method generates palettes that maximize the perceptual differences between channels while mitigating confusing color blending in overlapping channels. We integrate this method into a system that allows users to explore multi-channel image data and compare and evaluate color palettes for their data. An interactive lensing approach provides on-demand feedback on channel overlap and a color confusion metric while giving context to the underlying channel values. Color palettes can be applied globally or, using the lens, to local regions of interest. We evaluate our palette optimization approach using three graphical perception tasks in a crowdsourced user study with 150 participants, showing that users are more accurate at discerning and comparing the underlying data using our approach. Additionally, we showcase psudo in a case study exploring the complex immune responses in cancer tissue data with a biologist.

Neutrophil Extracellular Traps and Neutrophil-Derived Extracellular Vesicles: Common Players in Neutrophil Effector Functions

Neutrophil granulocytes are a central component of the innate immune system. In recent years, they have gained considerable attention due to newly discovered biological effector functions and their involvement in various pathological conditions. They have been shown to trigger mechanisms that can either promote or inhibit the development of autoimmunity, thrombosis, and cancer. One mechanism for their modulatory effect is the release of extracellular vesicles (EVs), that trigger appropriate signaling pathways in immune cells and other target cells. In addition, activated neutrophils can release bactericidal DNA fibers decorated with proteins from neutrophil granules (neutrophil extracellular traps, NETs). While NETs are very effective in limiting pathogens, they can also cause severe damage if released in excess or cleared inefficiently. Since NETs and EVs share a variety of neutrophil molecules and initially act in the same microenvironment, differential biochemical and functional analysis is particularly challenging. This review focuses on the biochemical and functional parallels and the extent to which the overlapping spectrum of effector molecules has an impact on biological and pathological effects.

Automated Measurements of Key Morphological Features of Human Embryos for IVF

A major challenge in clinical In-Vitro Fertilization (IVF) is selecting the highest quality embryo to transfer to the patient in the hopes of achieving a pregnancy. Time-lapse microscopy provides clinicians with a wealth of information for selecting embryos. However, the resulting movies of embryos are currently analyzed manually, which is time consuming and subjective. Here, we automate feature extraction of time-lapse microscopy of human embryos with a machine-learning pipeline of five convolutional neural networks (CNNs). Our pipeline consists of (1) semantic segmentation of the regions of the embryo, (2) regression predictions of fragment severity, (3) classification of the developmental stage, and object instance segmentation of (4) cells and (5) pronuclei. Our approach greatly speeds up the measurement of quantitative, biologically relevant features that may aid in embryo selection.

Pathfinder: Visual Analysis of Paths in Graphs

The analysis of paths in graphs is highly relevant in many domains. Typically, path-related tasks are performed in node-link layouts. Unfortunately, graph layouts often do not scale to the size of many real world networks. Also, many networks are multivariate, i.e., contain rich attribute sets associated with the nodes and edges. These attributes are often critical in judging paths, but directly visualizing attributes in a graph layout exacerbates the scalability problem. In this paper, we present visual analysis solutions dedicated to path-related tasks in large and highly multivariate graphs. We show that by focusing on paths, we can address the scalability problem of multivariate graph visualization, equipping analysts with a powerful tool to explore large graphs. We introduce Pathfinder (Figure 1), a technique that provides visual methods to query paths, while considering various constraints. The resulting set of paths is visualized in both a ranked list and as a node-link diagram. For the paths in the list, we display rich attribute data associated with nodes and edges, and the node-link diagram provides topological context. The paths can be ranked based on topological properties, such as path length or average node degree, and scores derived from attribute data. Pathfinder is designed to scale to graphs with tens of thousands of nodes and edges by employing strategies such as incremental query results. We demonstrate Pathfinder's fitness for use in scenarios with data from a coauthor network and biological pathways.

Recurrent vulvar Buschke-Löwenstein's tumor-like condylomata acuminata and Hodgkin's disease effectively treated with recombinant interferon-alpha 2c gel as adjuvant to electrosurgery

The local application of recombinant interferon-alpha 2c hydrogel (1 x 10(6) IU IFN-alpha 2c per g) given as an adjuvant after electrosurgery led to a complete cure of previously recalcitrant untreatable giant Buschke-Löwenstein's tumor-like condylomata acuminata of a 19-year-old patient suffering from Hodgkin's disease (stage II/II). Interferon-alpha 2c hydrogel given as adjuvant with surgery may have more direct antiproliferative and antiviral activities than immunomodulating defects. This combined topical application is an effective and safe treatment which is recommended especially in immunocompromised individuals suffering from genital HPV disease nonresponsive against systemic interferon and conventional therapy modalities.

Specific behaviour, mood and personality traits may contribute to obesity in patients with craniopharyngioma

INTRODUCTION

Patients with craniopharyngioma (CP) often suffer from obesity, but the underlying causes are still not fully understood. We compared CP to patients with nonfunctioning pituitary adenoma (NFPA) and to a control group (CG) using standardized questionnaires to investigate whether behavioural, mood or personality traits contribute to obesity.

METHODS

We compared 31 patients with CP (42% male, 53 ± 15·1 years) to 26 patients with NFPA (71% male, 63·2 ± 10·3 years) and to age- and gender-matched local CG (ratio 2:1). Normative data from the literature are included for reference. Patients were asked to complete eleven standardized questionnaires. Two questionnaires were used to evaluate eating disorders (FEV, EDE-Q), one depression (BDI), one anxiety (STAI), three health-related quality of life (SF-36, EuroQoL, QoL-AGHDA), one sleepiness (Epworth Sleepiness Scale), two personality (EPQ-RK, TPQ) and one body image (FKB-20).

RESULTS

Patients with CP scored significantly higher in conscious hunger perception (FEV, CP 5·8 ± 3·2 scores, NFPA 3·6 ± 3·3 scores, CG 3·0 ± 2·5, P < 0·001). They had similar scores for BDI compared with NFPA, but higher scores to CG (P < 0·001, CP 10·6 ± 8·3, NFPA 7·5 ± 5·7, CG 4·96 ± 4·2). CP and NFPA scored higher than CG for anxiety and personality traits such as harm avoidance, fatigability and asthenia and slightly higher for neuroticism. No differences were seen for EDE-Q, quality of life, daytime sleepiness and body image between CP and NFPA. However, differences could be observed to normative data from the literature.

CONCLUSION

Obesity in patients with CP might be influenced by eating disorders, negative mood alterations and increased anxiety-related personality traits.

Mittlerer Aktivitätskoeffizient von KCl in Zytoplasma-Fraktionen aus Kalbsleberzellen

Die Kenntnis der chemischen Potentiale der Salze im Zytoplasma gibt Aufschluß darüber, ob die Wechselwirkungen zwischen den Komponenten des Zytoplasmas mit dem Modell einer kompliziert zusammengesetzten, konzentrierten makromolekularen Lösung zu beschreiben sind oder ob im Zytoplasma ein hydratisiertes makromolekulares Netzwerk vorliegt, in dem die Salzionen durch starke Wechselwirkungen zum Teil immobilisiert werden, wie in der Sorptionstheorie von Troshin oder der Association-Induction-Hypothese von Ling angenommen wird.

Als Modell für das Zytoplasma dienten konzentrierte Zytoplasma-Fraktionen aus Kalbsleber, deren Salze vollständig durch KCl in physiologischer lonenstärke ersetzt wurden. Als Maß für das chemische Potential wurde neben den lonenkonzentrationen der mittlere Aktivitätskoeffizient von KCl über EMK-Messungen an einer Dreikompartment-Meßzelle mit einer Kationen- und einer Anionenaustauscher-Membranelektrode bestimmt. Die Ergebnisse zeigen, daß der mittlere Aktivitätskoeffizient von KCl in den Zytoplasma-Fraktionen mit steigender Makromolekülkonzentration abnimmt, aber nur geringfügig gegenüber dem Wert in reinen KCl-Lösungen gleicher Konzentration erniedrigt wird. Das gilt auch dann, wenn man bei der Berechnung der Ionenkonzentrationen etwa 0,4 g gebundenes Wasser pro g Makromolekül-Trockengewicht als non-solvent-Wasser berücksichtigt. Bei einer Bindung oder Immobilisierung der Salzionen in dem makromolekularen System wäre dagegen eine starke Erniedrigung der mittleren Aktivitätskoeffizienten zu erwarten.

Elektronenbestrahlung von p-n-Sperrschichten in GaAs

Es wird der Einfluß einer Elektronenbestrahlung auf p-n-Sperrschichten in Gallium-Arsenid untersucht und der Kurzschlußstrom bzw. die EMK in Abhängigkeit von der Strahlintensität gemessen. Bei Bestrahlung mit 45 kV-Elektronen ist der Kurzschlußstrom um den Faktor 7200 größer als der auffallende Elektronenstrom. Dem entspricht ein mittlerer Energiebedarf pro Ladungsträgerpaar von 6,3 eV. Die bei optimaler Anpassung abgegebene Leistung beträgt 8% der auffallenden Strahlintensität. Als Anwendung wird die Messung der Intensität von Elektronenbeugungs-Diagrammen beschrieben

Anxious and non-anxious forms of major depression: familial, personality and symptom characteristics

BACKGROUND

Earlier clinical studies have suggested consistent differences between anxious and non-anxious depression. The aim of this study was to compare parental pathology, personality and symptom characteristics in three groups of probands from the general population: depression with and without generalized anxiety disorder (GAD) and with other anxiety disorders. Because patients without GAD may have experienced anxious symptoms for up to 5 months, we also considered GAD with a duration of only 1 month to produce a group of depressions largely unaffected by anxiety.

METHOD

Depressive and anxiety disorders were assessed in a 10-year prospective longitudinal community and family study using the DSM-IV/M-CIDI. Regression analyses were used to reveal associations between these variables and with personality using two durations of GAD: 6 months (GAD-6) and 1 month (GAD-1).

RESULTS

Non-anxious depressives had fewer and less severe depressive symptoms, and higher odds for parents with depression alone, whereas those with anxious depression were associated with higher harm avoidance and had parents with a wider range of disorders, including mania.

CONCLUSIONS

Anxious depression is a more severe form of depression than the non-anxious form; this is true even when the symptoms required for an anxiety diagnosis are ignored. Patients with non-anxious depression are different from those with anxious depression in terms of illness severity, family pathology and personality. The association between major depression and bipolar disorder is seen only in anxious forms of depression. Improved knowledge on different forms of depression may provide clues to their differential aetiology, and guide research into the types of treatment that are best suited to each form.

Genetic variation in FKBP5 associated with the extent of stress hormone dysregulation in major depression

The FK506 binding protein 51 or FKBP5 has been implicated in the regulation of glucocorticoid receptor (GR) sensitivity, and genetic variants in this gene have been associated with mood and anxiety disorders. GR resistance and associated stress hormone dysregulation are among the most robust biological findings in major depression, the extent of which may be moderated by FKBP5 polymorphisms. FKBP5 mRNA expression in peripheral blood cells (baseline and following in vivo GR stimulation with 1.5 mg dexamethasone p.o.) was analyzed together with plasma cortisol, ACTH, dexamethasone levels and the FKBP5 polymorphism rs1360780 in 68 depressed patients and 87 healthy controls. We observed a significant (P = 0.02) interaction between disease status and FKBP5 risk allele carrier status (minor allele T) on GR-stimulated FKBP5 mRNA expression. Patients carrying the risk T allele, but not the CC genotype, showed a reduced induction of FKBP5 mRNA. This FKBP5 polymorphism by disease status interaction was paralleled by the extent of plasma cortisol and ACTH suppression following dexamethasone administration, with a reduced suppression only observed in depressed patients carrying the T allele. Only depressed patients carrying the FKBP5 rs1360780 risk allele showed significant GR resistance compared with healthy controls, as measured by dexamethasone-induced FKBP5 mRNA induction in peripheral blood cells and suppression of plasma cortisol and ACTH concentrations. This finding suggests that endocrine alterations in depressed patients are determined by genetic variants and may allow identification of specific subgroups.

Increased prevalence of anxiety-associated personality traits in patients with Cushing's disease: a cross-sectional study

BACKGROUND/AIMS

Chronic hypercortisolism in Cushing's disease (CD) has been suggested to contribute to an altered personality profile in these patients. We aimed to test this hypothesis and attempted to determine the effects of disease- and treatment-related factors that might moderate an altered personality in CD.

METHODS

We assessed 50 patients with CD (74% biochemically controlled) and compared them to 60 patients with non-functioning pituitary adenomas (NFPA) and 100 age- and gender-matched mentally healthy controls. Personality was measured by two standardized personality questionnaires, TPQ (Cloninger personality questionnaire) and EPQ-RK (Eysenck personality questionnaire-RK).

RESULTS

Compared to mentally healthy controls, CD patients reported significantly less novelty-seeking behaviour, including less exploratory excitability and less extravagance. On harm avoidant subscales, they presented with more anticipatory worries and pessimism, higher fear of uncertainty, shyness with strangers, fatigability and asthenia. Moreover, CD patients appeared to be less extraverted, more neurotic and socially desirable. CD patients differed from NFPA patients in terms of higher neuroticism scores, and NFPA patients did not show altered novelty-seeking behaviour or extraversion. In the subgroup analysis, CD patients with persistent hypercortisolism displayed significantly higher fear of uncertainty, fatigability and asthenia, indicating high harm avoidance in total, than those in biochemical remission.

CONCLUSION

Patients with CD showed a distinct pattern of personality traits associated with high anxiety in combination with traits of low externalizing behaviour. Such personality changes should be taken into account in the diagnosis and treatment of CD patients, as they might interfere with the patient-physician communication and/or challenge the patients' social and psychological functioning.

Interactive Volume Exploration of Petascale Microscopy Data Streams Using a Visualization-Driven Virtual Memory Approach

This paper presents the first volume visualization system that scales to petascale volumes imaged as a continuous stream of high-resolution electron microscopy images. Our architecture scales to dense, anisotropic petascale volumes because it: (1) decouples construction of the 3D multi-resolution representation required for visualization from data acquisition, and (2) decouples sample access time during ray-casting from the size of the multi-resolution hierarchy. Our system is designed around a scalable multi-resolution virtual memory architecture that handles missing data naturally, does not pre-compute any 3D multi-resolution representation such as an octree, and can accept a constant stream of 2D image tiles from the microscopes. A novelty of our system design is that it is visualization-driven: we restrict most computations to the visible volume data. Leveraging the virtual memory architecture, missing data are detected during volume ray-casting as cache misses, which are propagated backwards for on-demand out-of-core processing. 3D blocks of volume data are only constructed from 2D microscope image tiles when they have actually been accessed during ray-casting. We extensively evaluate our system design choices with respect to scalability and performance, compare to previous best-of-breed systems, and illustrate the effectiveness of our system for real microscopy data from neuroscience.

Cognitive function in acromegaly: description and brain volumetric correlates

In acromegaly, we reported on increased rates of affective disorders such as dysthymia and depression, as well as structural brain changes. Objective of this study was to determine if cognitive impairments in patients with acromegaly exist and whether such impairments are associated with structural brain alterations defined by magnetic resonance imaging (MRI). In this cross-sectional study, 55 patients with biochemically confirmed acromegaly were enrolled. MRI data were compared with 87 control subjects. Main outcome measures were performance levels in 13 cognitive tests covering the domains of attention, memory and executive function, with performance below the cut-off level of the 16th percentile rated as impaired. In addition, individual global and hippocampal volume changes were defined for each patient in reference to a normative sample. We found that up to 33.3% of the patients were impaired in the attention, up to 24.1% in the memory, and up to 16.7% in the executive function domain. 67.3% of the patients failed to reach the cut-off level in at least one subtest. MRI demonstrated increased global, left and right hippocampal grey matter and white matter, particularly early in the disease course. Rather few positive than expected negative correlations could be established between the hippocampal grey matter gain and cognitive performance. Cognitive dysfunction, particularly attentional deficits, are common in acromegaly, rendering neuropsychological testing essential in the diagnostic work-up.

Distinct dopaminergic personality patterns in patients with prolactinomas: a comparison with nonfunctioning pituitary adenoma patients and age- and gender-matched controls

INTRODUCTION

Personality patterns such as extraversion and novelty seeking have been associated with an altered dopaminergic activity in healthy subjects. Patients with prolactinomas have been described as exhibiting an altered dopaminergic tone and are often treated with dopamine agonists. Little is known about the personality traits of this patient group. Hence, we aimed at examining whether patients with prolactinomas exhibit modified personality patterns compared to patients with nonfunctioning pituitary adenomas and healthy controls.

SUBJECTS/METHODS

In this cross-sectional study, 86 patients with prolactinomas and 58 patients with nonfunctioning pituitary adenomas (NFPA) were compared with 172 mentally healthy age- and gender-matched controls. To assess personality traits, standardized personality questionnaires (Eysenck personality questionnaire-EPQ-RK and Tridimensional Personality Questionnaire devised by Cloninger-TPQ) were administered.

RESULTS

Patients with either prolactinomas or NFPA showed a distinct personality profile compared to the normal population, characterized by increased neuroticism and they also answered in a socially desirable mode. On harm-avoidant total and subscales, they presented with a higher fear of uncertainty and also increased fatigability and asthenia. The prolactinoma patients, when contrasted with the 'clinical' control group of patients with NFPA and after post hoc tests for multiple comparisons following the Bonferroni-Holm procedure showed significantly reduced extraversion (p = 0.044) and increased shyness with strangers (p = 0.044), tending to be more neurotic and present lower scores in the novelty seeking subscale impulsiveness.

CONCLUSION

This is, to our knowledge, the first study providing new evidence of an altered personality profile of prolactinoma patients which might affect the patient-doctor relationship, treatment and patient's quality of life.

Somatization in major depression--clinical features and genetic associations

OBJECTIVE

To identify clinical variables and genetic variations within monoaminergic genes known to be implicated in pain perception that are associated with the occurrence of somatization symptoms in patients with major depression.

METHOD

Somatization was evaluated using the respective subscale of the Symptom Checklist SCL-90-R. Six monoaminergic genes were identified showing an involvement in pain perception and somatization according to the literature: COMT, HTR2A, SLC6A2, SLC6A4, DRD4, and TPH1. One hundred and eighteen single nucleotide polymorphisms (SNPs) within these genes were genotyped using Illumina BeadChips in a sample of 398 at least moderately to severely depressed in-patients participating in the Munich Antidepressant Response Signature (MARS) project.

RESULTS

Thirty SNPs exhibit nominally significant associations with somatization. One SNP (rs9534505) located in intron 2 of the HTR2A gene withstood correction for multiple testing. Clinical data provide further evidence for strong impact of somatization on the presentation of depressive symptoms and description of a patient subgroup with unfavorable clinical outcome.

CONCLUSION

Our results demonstrate the influence of a HTR2A polymorphism on aspects of somatization in major depression, which co-occurs with an unfavorable antidepressant treatment outcome. These results confirm and expand previous findings on somatization as a risk factor for treatment outcome in major depression.

Factors associated with the seroprevalence of 26 cutaneous and two genital human papillomavirus types in organ transplant patients

Viral skin infections are commonly present in organ transplant recipients (OTR). In this study, we aimed to identify factors associated with human papillomavirus (HPV) infections in OTR. Patients with solid-organ transplants were recruited from the outpatient nephrology and dermatology clinics in five European countries. Only patients with no current or past skin cancer were included in this analysis. Serum samples were analysed for antibodies to the L1 proteins of 26 cutaneous and two genital HPV types from five phylogenetic genera (α, β, γ, μ and ν). The most consistent association was found between recreational sun exposure and the seroprevalence of all tested genera, except α. The antibody presence of any β type was higher among people who had been transplanted at least 23 years prior to participation than in those who had been transplanted for less than 7 years. The prevalence of two γ-HPV types (60 and 65) and three β-HPV types (15, 38 and 49) was associated with time since transplantation. The presence of a high number of warts was associated with the presence of any μ-PV or ν-PV types, and having greater than 50 keratotic skin lesions was almost significantly associated with the presence of antibodies to two or more γ-PV. Discrepancies in the results of the present study, as well as in previous reports, may depend on different methodologies and on geographical variations. Our results also indicate that further research with more standardized methods is needed to clarify the role of cutaneous HPV in OTR.

A case-control study of betapapillomavirus infection and cutaneous squamous cell carcinoma in organ transplant recipients

We examined the association between betapapillomavirus (betaPV) infection and cutaneous squamous cell carcinoma (SCC) in organ transplant recipients. A total of 210 organ transplant recipients with previous SCC and 394 controls without skin cancer were included. The presence of 25 betaPV types in plucked eyebrow hairs was determined using a human papillomavirus (HPV) DNA genotyping assay, and antibodies for the 15 most prevalent betaPV types were detected using multiplex serology. We used multivariate logistic regression models to estimate associations between various measures of betaPV infection and SCC. BetaPV DNA was highly prevalent (>94%) with multiple types frequently detected in both groups. We found a significant association between SCC and the concordant detection of both antibodies and DNA for at least one betaPV type (adjusted OR 1.6; 95% CI 1.1;2.5). A borderline-significant association with SCC was found for HPV36 (adjusted OR 2.4; CI 1.0;5.4), with similar associations for HPV5, HPV9 and HPV24. These data provide further evidence of an association between betaPV infection and SCC in organ transplant recipients. Confirmation of a betaPV profile predictive of risk for SCC may pave the way for clinically relevant pretransplant HPV screening and the development of preventive and therapeutic HPV vaccination.

More CLEC16A gene variants associated with multiple sclerosis

OBJECTIVES

Recently, associations of several single-nucleotide polymorphisms (SNPs) within the CLEC16A gene with multiple sclerosis (MS), type-I diabetes, and primary adrenal insufficiency were reported.

METHODS

We performed linkage disequilibrium (LD) fine mapping with 31 SNPs from this gene, searching for the region of highest association with MS in a German sample consisting of 603 patients and 825 controls.

RESULTS

Four SNPs located in intron 19 of the CLEC16A gene were found associated. We could replicate the finding for SNP rs725613 and were able to show for the first time the association of rs2041670, rs2080272 and rs998592 with MS.

CONCLUSION

All described base polymorphisms are mapping to one LD block of approximately 50 kb within intron 19 of the CLEC16A gene, suggesting a pivotal role of this region for susceptibility of MS and possibly also for other autoimmune diseases.

Attachment of a long-tailed Rhizobium bacteriophage to the pili of its host

Bacterial strain 16-12 was isolated from the root nodules of lupines and was found to be mitomycin C-inducible for the production of a bacteriophage ("16-12-1") with a long noncontractile tail. The phage was found to attach with a fork-like terminal tail structure to the pili of strain 16-12. In addition, it was also found adsorbed to the bacterial cell poles. It is suggested that phage 16-12-1 may be pilus dependent.

An analysis of clustering of betapapillomavirus antibodies

Betapapillomaviruses (betaPVs) may contribute to the aetiology of cutaneous squamous cell carcinoma. However, no high-risk types have yet been identified, possibly because the high frequency of co-infection prevents a straightforward analysis of the independent effects of individual viruses. This study aimed to determine whether specific virus types were more likely to co-occur than others, thereby reducing the number of parameters needed in statistical models. Antibody data were analysed from controls who participated in case-control studies in The Netherlands, Italy and Australia and from participants in the German Nutrition Survey. Cluster analysis and two ordination techniques were used to identify patterns. Evidence of clustering was found only according to the number of viruses to which antibodies were detected. The lack of clustering of specific viral types identified suggests that if there are betaPV types that are independently related to skin carcinogenesis, they are unlikely to be identified using standard epidemiological methods.

Anal carcinoma in human immunodeficiency virus-positive men: results of a prospective study from Germany

BACKGROUND

Anal intraepithelial neoplasia (AIN), a human papillomavirus (HPV)-associated potential precursor lesion of anal cancer, is frequent among human immunodeficiency virus (HIV)-positive men who have sex with men (MSM). There is a paucity of data published on the progression of high-grade AIN to invasive cancer as well as on clinical and virological characteristics comparing anal margin and anal canal carcinoma.

OBJECTIVES

To search for anal carcinoma and AIN in a large series of HIV-positive MSM, to assess treatment response of anal carcinoma, and to analyse lesional HPV spectrum of anal cancers.

METHODS

Detection of anal carcinoma and AIN was performed using cytology, high-resolution anoscopy, and histology in case of abnormal findings. Additionally, HPV analyses for 36 high- and low-risk α-HPV types were performed in patients with anal carcinoma.

RESULTS

In total, 446 German HIV-positive MSM were examined within an observation period of 5 years and 10 months. Of these, 116 (26·0%) patients had normal findings, 163 (36·5%) had low-grade AIN, 156 (35·0%) had high-grade AIN, and 11 (2·5%) had anal carcinoma as evidenced by the highest grade of cytology/histology. Five patients with anal cancer, who had refused treatment of their precancerous lesions, had progressed from high-grade AIN to invasive cancer within a median time of 8·6 months. All anal cancers carried high-risk α-HPV types. All five squamous cell carcinomas (SCCs) of the anal canal were HPV16 positive. In contrast, only one of the four anal margin SCCs were HPV16 positive (HPV31, HPV33 and HPV33 + HPV68 were found in the other three anal margin SCCs). HPV59 was found in two adenocarcinomas, one of which additionally carried HPV33. In contrast to the cancer biopsies, a broad spectrum of surface high- and low-risk HPV types was found in anal swabs of the patients. Surgical excision resulted in long-term disease control of all anal margin carcinomas, whereas combined chemoradiotherapy in carcinomas of the anal canal was associated with high recurrence rates, high toxicity, and high mortality.

CONCLUSIONS

Anal carcinoma and AIN are frequent in HIV-positive men, even in patients participating in anal cancer prevention programmes. High-grade dysplasia in these patients can progress to invasive cancer within a short period of time. Anal margin carcinoma and anal canal carcinoma differ substantially in their lesional HPV spectrum, prognosis and treatment response.

Investigation of 17 candidate genes for personality traits confirms effects of the HTR2A gene on novelty seeking

Genes involved in serotonergic and dopaminergic neurotransmission have been hypothesized to affect different aspects of personality, but findings from genetic association studies did not provide conclusive results so far. In previous studies, however, only one or a few polymorphisms within single genes were investigated neglecting the possibility that the genetic associations might be more complex comprising several genes or gene regions. To overcome this limitation, we performed an extended genetic association study analyzing 17 serotonergic (SLC6A4, HTR1A, HTR1B, HTR2A, HTR2C, HTR3A, HTR6, MAOA, TPH1, TPH2) and dopaminergic genes (SLC6A3, DRD2, DRD3, DRD4, COMT, MAOA, TH, DBH), which have been previously reported to be implicated with personality traits. One hundred and ninety-five single nucleotide polymorphisms (SNPs) within these genes were genotyped with the Illumina BeadChip technology (HumanHap300, Human-1) in a sample of 366 mentally healthy Caucasians. Additionally, we tried to replicate our results in an independent sample of further 335 Caucasians. Personality traits in both samples were assessed with the German version of Cloninger's Tridimensional Personality Questionnaire. From 30 SNPs showing associations at a nominal level of significance, two intronic SNPs, rs2770296 and rs927544, both located in the HTR2A gene, withstood correction for multiple testing. These SNPs were associated with the personality trait novelty seeking. The effect of rs927544 could be replicated for the novelty seeking subscale extravagance, and the same SNP was also associated with extravagance in the combined samples. Our results show that HTR2A polymorphisms modulate facets of novelty seeking behaviour in healthy adults suggesting that serotonergic neurotransmission is involved in this phenotype.

Reduced memory and attention performance in a population-based sample of young adults with a moderate lifetime use of cannabis, ecstasy and alcohol

Regular use of illegal drugs is suspected to cause cognitive impairments. Two substances have received heightened attention: 3,4-methylenedioxymethamphetamine (MDMA or 'ecstasy') and delta-9-tetrahydrocannabinol (THC or 'cannabis'). Preclinical evidence, as well as human studies examining regular ecstasy consumers, indicated that ecstasy use may have negative effects on learning, verbal memory and complex attentional functions. Cannabis has also been linked to symptoms of inattention and deficits in learning and memory. Most of the published studies in this field of research recruited participants by means of newspaper advertisements or by using word-of-mouth strategies. Because participants were usually aware that their drug use was critical to the research design, this awareness may have caused selection bias or created expectation effects. Focussing on attention and memory, this study aimed to assess cognitive functioning in a community-based representative sample that was derived from a large-scale epidemiological study. Available data concerning drug use history allowed sampling of subjects with varying degrees of lifetime drug experiences. Cognitive functioning was examined in 284 young participants, between 22 and 34 years. In general, their lifetime drug experience was moderate. Participants completed a neuropsychological test battery, including measures for verbal learning, memory and various attentional functions. Linear regression analysis was performed to investigate the relationship between cognitive functioning and lifetime experience of drug use. Ecstasy and cannabis use were significantly related to poorer episodic memory function in a dose-related manner. For attentional measures, decrements of small effect sizes were found. Error measures in tonic and phasic alertness tasks, selective attention task and vigilance showed small but significant effects, suggesting a stronger tendency to experience lapses of attention. No indication for differences in reaction time was found. The results are consistent with decrements of memory and attentional performance described in previous studies. These effects are relatively small; however, it must be kept in mind that this study focussed on assessing young adults with moderate drug use from a population-based study.

Human papillomavirus-associated induction of human beta-defensins in anal intraepithelial neoplasia

BACKGROUND

Antimicrobial peptides and proteins (AMPs) are widely distributed effector molecules of the innate immune system with well-known antibacterial activity. However, there is a paucity of information regarding antiviral effects of AMPs.

OBJECTIVES

The present study was performed to analyse expression of AMPs in human papillomavirus (HPV)-associated anal skin lesions of human immunodeficiency virus (HIV)-positive men who have sex with men (MSM), a special high-risk group for persistent HPV infections and anal dysplasia.

METHODS

Skin lesions were analysed for the presence of LL-37, RNase 7, and human beta-defensin (hBD)-1, hBD-2 and hBD-3. Moreover, HPV typing and HPV DNA load determination for HPV types 6, 11, 16, 18, 31 and 33 were performed to evaluate possible correlations between expression of AMPs and lesional HPV types.

RESULTS

Skin biopsies of 45 HIV-positive MSM with anal intraepithelial neoplasia (AIN), anal condylomata acuminata or unaffected anal mucosa, as well as condylomata acuminata of eight HIV-negative MSM, were analysed for AMP mRNA expression. Additionally, immunohistochemical analysis for hBD-2 and hBD-3 was performed in a total of 45 samples. hBD-2 and hBD-3 gene and protein expression was significantly increased in both AIN and condyloma, whereas LL-37, RNase 7 and hBD-1 gene expression did not differ significantly from unaffected anal mucosa. AMP expression correlated neither with the number of HPV types nor with the high-risk and low-risk HPV DNA loads of the quantified types. No significant differences in AMP expression were observed in condylomata of HIV-positive and HIV-negative MSM.

CONCLUSIONS

hBD-2 and hBD-3 expression was shown to be significantly upregulated in HPV-associated anal skin lesions of both HIV-positive and HIV-negative MSM. Their biological significance in the innate immunity against these lesions needs further research.