Parental inconsistency, impulsive choice and neural value representations in healthy adolescents

A well-characterized potential marker for addiction is impulsive choice, stably measured by delay discounting (DD) paradigms. While genetic influences partly account for inter-individual variance in impulsivity, environmental factors such as parenting practices may have an important role. The present study investigates how inconsistent fulfillment of delayed reward promises impacts on DD. A combined correlational and experimental functional magnetic resonance imaging (fMRI) design was performed in a sample of 48 healthy adolescents (13-15 years). More specifically, neural activation during a DD task was investigated at two assessment points (T0 and T1). Adolescents' self-reports of parenting and substance use were assessed at T0. Between assessment points, we experimentally varied the reliability of delayed reward promises, measuring the impact of this intervention on DD and neural value processing at T1. In the correlational part, same-sex parent reward inconsistency was associated with steeper DD and an attenuated subjective value (SV) representation in the nucleus accumbens (NAcc) and ventromedial prefrontal cortex (vmPFC). Steeper DD was in turn associated with alcohol use during the past year. In the experimental part, the reward inconsistency manipulation resulted in an attenuation of the NAcc SV representation, similar to the parental inconsistency effect. Together, our correlational and experimental findings raise new light on how parents may influence their children's degree of impulsivity, making parenting a potential target in addiction prevention.

[Mass maritime casualty incidents in German waters: structures and resources]

The Central Command for Maritime Emergencies was founded in Germany in 2003 triggered by the fire on board of the cargo ship "Pallas" in 1998. Its mission is to coordinate and direct measures at or above state level in maritime emergency situations in the North Sea and the Baltic Sea. A special task in this case is to provide firefighting and medical care. To face these challenges at sea emergency doctors and firemen have been specially trained. This form of organization provides a concept to counter mass casualty incidents and peril situations at sea. Since the foundation of the Central Command for Maritime Emergencies there have been 5 operations for firefighting units and 4 for medical response teams. Assignments and structure of the Central Command for Maritime Emergencies are unique in Europe.

Rasmussen's encephalitis presenting as focal cortical dysplasia

Rasmussen's encephalitis is a rare syndrome characterized by intractable seizures, often associated with epilepsia partialis continua and symptoms of progressive hemispheric dysfunction. Seizures are usually the hallmark of presentation, but antiepileptic drug treatment fails in most patients and is ineffective against epilepsia partialis continua, which often requires surgical intervention. Co-occurrence of focal cortical dysplasia has only rarely been described and may have implications regarding pathophysiology and management. We describe a rare case of dual pathology of Rasmussen's encephalitis presenting as a focal cortical dysplasia (FCD) and discuss the literature on this topic.

Prevalence of antibodies against influenza A and B viruses in children in Germany, 2008 to 2010

The prevalence of influenza A and B virus-specific IgG was determined in sera taken between 2008 and 2010 from 1,665 children aged 0-17 years and 400 blood donors in Germany. ELISA on the basis of whole virus antigens was applied. Nearly all children aged nine years and older had antibodies against influenza A. In contrast, 40% of children aged 0-4 years did not have any influenza A virus-specific IgG antibodies. Eightysix percent of 0-6 year-olds, 47% of 7-12 year-olds and 20% of 13-17 year-olds were serologically naïve to influenza B viruses. By the age of 18 years, influenza B seroprevalence reached approximately 90%. There were obvious regional differences in the seroprevalence of influenza B in Germany. In conclusion, seroprevalences of influenza A and influenza B increase gradually during childhood. The majority of children older than eight years have basal immunity to influenza A, while comparable immunity against influenza B is only acquired at the age of 18 years. Children aged 0-6 years, showing an overall seroprevalence of 67% for influenza A and of 14% for influenza B, are especially at risk for primary infections during influenza B seasons.

Phenotypic spectrum of epidermolysis bullosa associated with α6β4 integrin mutations

BACKGROUND

Integrin α6β4 is a transmembrane receptor and a key component of the hemidesmosome anchoring complex. It is involved in cell-matrix adhesion and signalling in various tissues. Mutations in the ITGA6 and ITGB4 genes coding for α6β4 integrin compromise dermal-epidermal adhesion and are associated with skin blistering and pyloric atresia (PA), a disorder known as epidermolysis bullosa with PA (EB-PA).

OBJECTIVES

To elucidate the molecular pathology of skin fragility in eight cases, disclose the underlying ITGA6 and ITGB4 mutations and study genotype-phenotype correlations.

METHODS

DNA was isolated from ethylenediaminetetraacetic acid-blood samples, and the coding exons and exon-intron boundaries of ITGA6 and ITGB4 were amplified by polymerase chain reaction (PCR), and directly sequenced. Skin samples were submitted to immunofluorescence mapping with antibodies to adhesion proteins of the dermal-epidermal junction. Primary keratinocytes were isolated, and used for RNA and protein extraction, reverse transcription PCR and immunoblotting. Ultrastructural analysis of the skin was performed in one patient.

RESULTS

We disclose 10 novel mutations, one in ITGA6 and nine in ITGB4. Skin cleavage was either intraepidermal or junctional. Lethal outcome and PA correlated with loss-of-function mutations in two cases. Solely mild skin involvement was associated with deletion of the C-terminus of β4 integrin. Combinations of missense, nonsense or frameshift mutations caused severe urinary tract involvement in addition to skin fragility in five cases.

CONCLUSIONS

The present study reveals novel ITGA6 and ITGB4 gene mutations and supports previous reports showing that the phenotype may lack PA and be limited to skin and nail involvement. In four out of six cases of EB-PA, life expectancy was not impaired. A high frequency of urinary tract involvement was found in this study, and represented the main cause of morbidity. Low levels of β4 integrin expression were compatible with hemidesmosomal integrity and a mild skin phenotype.

Rapid enzymatic hydrolysis of masked deoxynivalenol and zearalenone prior to liquid chromatography mass spectrometry or immunoassay analysis

Recently it has been shown that conjugates (‘masked mycotoxins’) may contribute to the total daily intake of hazardous mycotoxins. Therefore, there is an urgent need for rapid analysis methods that assess the level of both free and masked mycotoxins in food and feed. However, the analysis of masked mycotoxins by either immunoassays or instrumental methods, such as liquid chromatography tandem mass spectrometry (LC-MS/MS), is severely hindered by the lack of standards and the unpredictable cross-reactivity profiles of the available antibodies. In this work, 26 enzymes were explored for rapid hydrolysis of masked mycotoxins using deoxynivalenol-3-glucoside (DON-3G) as model compound. Following initial screening, the most promising enzyme, a fungal 1,3-β-glucanase (laminarinase), was investigated in detail and found to be fit-for-purpose, providing complete conversions in minutes rather than hours according to LC-MS/MS analyses. As a proof of concept, the enzymatic pretreatment was applied to an extract of beer containing DON-3G. In addition, the feasibility of a fully automated enzymatic pretreatment of masked mycotoxin standards in an autosampler was demonstrated in an imaging surface plasmon resonance immunoassay set-up. Such an automated pretreatment was found to be equally applicable to other mycotoxin conjugates, as shown by the conversion of zearalenone-14-β-D-glucopyranoside and zearalenone-14-sulphate, in the latter case using a sulphatase enzyme. It is envisaged that laminarinase could be useful for other masked mycotoxins as well.

The clinical effectiveness and cost-effectiveness of cetuximab (mono- or combination chemotherapy), bevacizumab (combination with non-oxaliplatin chemotherapy) and panitumumab (monotherapy) for the treatment of metastatic colorectal cancer after first-line chemotherapy (review of technology appraisal No.150 and part review of technology appraisal No. 118): a systematic review and economic model

BACKGROUND

Colorectal cancer is the third most commonly diagnosed cancer in the UK after breast and lung cancer. People with metastatic disease who are sufficiently fit are usually treated with active chemotherapy as first- or second-line therapy. Recently, targeted agents have become available including anti-epidermal growth factor receptor (EGFR) agents, for example cetuximab and panitumumab, and anti-vascular endothelial growth factor (VEGF) receptor agents, for example bevacizumab.

OBJECTIVE

To investigate the clinical effectiveness and cost-effectiveness of panitumumab monotherapy and cetuximab (mono- or combination chemotherapy) for Kirsten rat sarcoma (KRAS) wild-type (WT) patients, and bevacizumab in combination with non-oxaliplatin chemotherapy, for the treatment of metastatic colorectal cancer after first-line chemotherapy.

DATA SOURCES

The assessment comprises a systematic review of clinical effectiveness and cost-effectiveness studies, a review and critique of manufacturer submissions and a de novo cohort-based economic analysis. For the assessment of effectiveness, a literature search was conducted in a range of electronic databases, including MEDLINE, EMBASE and The Cochrane Library, from 2005 to November 2010.

REVIEW METHODS

Studies were included if they were randomised controlled trials (RCTs) or systematic reviews of RCTs of cetuximab, bevacizumab or panitumumab in participants with EGFR-expressing metastatic colorectal cancer with KRAS WT status that has progressed after first-line chemotherapy (for cetuximab and panitumumab) or participants with metastatic colorectal cancer that has progressed after first-line chemotherapy (bevacizumab). All steps in the review were performed by one reviewer and checked independently by a second. Synthesis was mainly narrative. An economic model was developed focusing on third-line and subsequent lines of treatment. Costs and benefits were discounted at 3.5% per annum. Probabilistic and univariate deterministic sensitivity analyses were performed.

RESULTS

The searches identified 7745 titles and abstracts. Two clinical trials (reported in 12 papers) were included. No data were available for bevacizumab in combination with non-oxaliplatin-based chemotherapy in previously treated patients. Neither of the included studies had KRAS status performed prospectively, but the studies did report retrospective analyses of the results for the KRAS WT subgroups. Third-line treatment with cetuximab plus best supportive care or panitumumab plus best supportive care appears to have statistically significant advantages over treatment with best supportive care alone in patients with KRAS WT status. For the economic evaluation, five studies met the inclusion criteria. The base-case incremental cost-effectiveness ratio (ICER) for KRAS WT patients for cetuximab compared with best supportive care is £98,000 per quality-adjusted life-year (QALY), for panitumumab compared with best supportive care is £150,000 per QALY and for cetuximab plus irinotecan compared with best supportive care is £88,000 per QALY. All ICERs are sensitive to treatment duration.

LIMITATIONS

In the specific populations of interest, there is a lack of evidence on bevacizumab, cetuximab and cetuximab plus irinotecan used second line and on bevacizumab and cetuximab plus irinotecan used third line. For cetuximab plus irinotecan treatment for KRAS WT people, there is no direct evidence on progression-free survival, overall survival and duration of treatment.

CONCLUSIONS

Although cetuximab and panitumumab appear to be clinically beneficial for KRAS WT patients compared with best supportive care, they are likely to represent poor value for money when judged by cost-effectiveness criteria currently used in the UK. It would be useful to conduct a RCT for patients with KRAS WT status receiving cetuximab plus irinotecan.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Dynamics measured by neutron scattering correlates with the organization of bioenergetics complexes in natural membranes from hyperthermophile and mesophile bacteria

Various models on membrane structure and organization of proteins and complexes in natural membranes emerged during the last years. However, the lack of systematic dynamical studies to complement structural investigations hindered the establishment of a more complete picture of these systems. Elastic incoherent neutron scattering gives access to the dynamics on a molecular level and was applied to natural membranes extracted from the hyperthermophile Aquifex aeolicus and the mesophile Wolinella succinogenes bacteria. The results permitted to extract a hierarchy of dynamic flexibility and atomic resilience within the samples, which correlated with the organization of proteins in bioenergetics complexes and the functionality of the membranes.