Thrombophilia in the young

Venous thromboembolism (VTE) is a rare disease that is being increasingly diagnosed and recognized in paediatrics in the past decade, usually as a secondary complication of primary severe underlying diseases. Apart from acquired thrombophilic risk factors, such as lupus anticoagulants, inherited thrombophilias (IT) have been established as risk factors for venous thromboembolic events in adults. In children with idiopathic VTE and in paediatric populations in which thromboses were associated with underlying medical diseases, IT have been described as additional prothrombotic risk factors. Follow-up data for VTE recurrence in children are available and suggest a recurrence rate of approximately 3% in neonates and 8% in other children. Here we present a review of the impact of IT on early onset of VTE and recurrence in children. Statistically significant associations between the IT traits investigated, e.g. factor V G1691A, factor II G20210A, protein C-, protein S-, antithrombin deficiency, elevated lipoprotein (a), combined IT and VTE onset were reported. In addition, statistically significant associations with recurrent VTE were calculated for protein S-, antithrombin-deficiency, and the factor II variant and combined IT. The absolute risk increase for VTE recurrence associated with IT ranged from 9.8 % for children carrying the factorII variant to 26% and 29% in children with combined IT and protein S-deficiency, respectively. Data obtained gave evidence that the detection of IT is clinically meaningful in children with VTE and underlines the importance of a paediatric thrombophilia screening program. Based on these data treatment algorithms have to be discussed.

Association between single nucleotide polymorphisms in the lysyl oxidase-like 1 gene and spontaneous cervical artery dissection

BACKGROUND

Spontaneous cervical artery dissection (sCAD) is a common cause of stroke in patients below 55 years. Dermal connective tissue abnormalities have been observed in up to 60% of patients. A chromosomal locus for connective tissue abnormalities associated with sCAD has been mapped to chromosome 15q24 to a candidate region containing the lysyl oxidase-like 1 gene (LOXL1). LOXL1 an excellent candidate susceptibility gene for non-familial sCAD was investigated by mutation analysis and a genetic association study.

METHODS

We sequenced the whole coding region of the LOXL1 gene in 15 sCAD patients and performed a genetic association study in 157 sCAD patients using 12 single nucleotide polymorphisms (SNP).

RESULTS

The SNP rs3825942 (Gly153Asp) showed marginal association with sCAD on an allele basis and in the dominant genetic model, and intronic SNP rs893817 under a recessive model only. None of the SNP haplotypes was associated with sCAD.

CONCLUSIONS

Genetic variation in LOXL1 might play a role as a risk factor for sCAD.

[Hospital emergency plan for the management of patients with highly contagious diseases]

Patients with imported highly contagious diseases like viral hemorrhagic fever (VHF), pneumonic plague or anthrax require special preventive measures and strict isolation. In addition, new emerging infections like severe acute respiratory syndrome (SARS) and epidemic influenza also have to be taken into account. At present five high security infectious disease units for patient care are available in Germany. Due to the relatively nonspecific symptoms, a patient with one of these infections may also be admitted to any other hospital. Therefore each hospital should develop a concept for the management and control of these lifethreatening highly contagious diseases. The present article describes the current emergency plan developed for the management of patients with highly contagious diseases at Hannover Medical School.

Prepulse inhibition of the startle reflex and its attentional modulation in the human S-ketamine and N,N-dimethyltryptamine (DMT) models of psychosis

Patients with schizophrenia exhibit diminished prepulse inhibition (PPI) of the acoustic startle reflex and deficits in the attentional modulation of PPI. Pharmacological challenges with hallucinogens are used as models for psychosis in both humans and animals. Remarkably, in contrast to the findings in schizophrenic patients and in animal hallucinogen models of psychosis, previous studies with healthy volunteers demonstrated increased levels of PPI after administration of low to moderate doses of either the antiglutamatergic hallucinogen ketamine or the serotonergic hallucinogen psilocybin. The aim of the present study was to investigate the influence of moderate and high doses of the serotonergic hallucinogen N,N-dimethyltryptamine (DMT) and the N-methyl-D-aspartate antagonist S-ketamine on PPI and its attentional modulation in humans. Fifteen healthy volunteers were included in a double-blind cross-over study with two doses of DMT and S-ketamine. Effects on PPI and its attentional modulation were investigated. Nine subjects completed both experimental days with the two doses of both drugs. S-ketamine increased PPI in both dosages, whereas DMT had no significant effects on PPI. S-ketamine decreased and DMT tended to decrease startle magnitude. There were no significant effects of either drug on the attentional modulation of PPI. In human experimental hallucinogen psychoses, and even with high, clearly psychotogenic doses of DMT or S-ketamine, healthy subjects failed to exhibit the predicted attenuation of PPI. In contrast, PPI was augmented and the startle magnitude was decreased after S-ketamine. These data point to important differences between human hallucinogen models and both animal hallucinogen models of psychosis and naturally occurring schizophrenia.

Consensus recommendation from a group of German experts for the use of enfuvirtide in heavily pretreated HIV patients

BACKGROUND

The EU approval of enfuvirtide (Fuzeon) was granted in May 2003 on the basis of the 48-week data from the TORO 1 and TORO 2 studies. Enfuvirtide is licensed for use in pretreated HIV patients experienced with three classes of drugs who exhibited treatment failure or who have shown intolerance to previous antiretroviral treatment regimens. Recent studies with the new protease inhibitors tipranavir and darunavir (RESIST and POWER studies) showed that a high proportion of heavily pretreated HIV patients achieve a viral load reduction to below the limit of detection when treated with enfuvirtide plus one of these new ritonavir-boosted protease inhibitors and an optimised background treatment regimen. The International AIDS Society (IAS-USA Panel) has recently updated its treatment guidelines in view of these new data and recommends the use of an antiretroviral treatment regimen containing at least two active drugs, one of which that has a new mechanism of action, for HIV patients who have been heavily pretreated. A new treatment goal has also emerged for heavily pretreated patients with advanced HIV disease: reduction of the viral load to below the detection limit of 50 copies/ml. The IAS concluded that the likelihood of achieving this treatment goal is higher when enfuvirtide is selected as one of the two active drugs.

OBJECTIVE

A panel of German experts convened to discuss the currently available data and to incorporate them into the updated German consensus recommendations for the use of enfuvirtide when switching treatment in heavily pretreated HIV patients.

METHODS

The consensus recommendations are based on published data from controlled, randomised clinical studies and on the expert opinions of the discussants.

RESULTS AND CONCLUSIONS

The consensus recommendations were developed to provide practice-relevant standardised recommendations for selecting suitable candidates for enfuvirtide therapy and for their management. Aspects including predictive prognostic factors, disease stage, selection of the optimised background regimen, early indicators of a response to enfuvirtide, as well as accompanying educational measures treatment were considered. New protease inhibitors or other remaining active drugs should be used together with enfuvirtide in heavily pretreated patients in order to enable at least two active drugs to be included in such a salvage regimen.

Differential microglial regulation in the human spinal cord under normal and pathological conditions

As the primary intrinsic immune effector cells of the central nervous system, microglia are involved in virtually all pathological processes of the brain and spinal cord including inflammatory, neurodegenerative, traumatic, neoplastic and vascular diseases. Despite this important role, there is a lack of data concerning microglial distribution and protein expression in the human spinal cord. In this study, we immunohistochemically investigated 10 normal human spinal cords to establish reference data and compared these results with 15 pathological human spinal cords deriving from distinct pathologies. Each spinal cord was evaluated at eight different levels for three white and two grey matter areas for both constitutive (MHC-II, CD68, IL-16, AIF-1, LCA, CD4) and reactive (MRP-8, MRP-14) microglial antigens. Whereas previous studies revealed significant regional differences in microglial distribution and protein expression in human brain, normal spinal cord displayed a uniform expression pattern, reaching levels of up to 17% MHC-II positive cells of the total cell population. This datum formed the basis for the further evaluation of microglia expression levels in pathological spinal cords, where levels of up to 45% positive cells were observed. Our results represent important reference values for future neuropathological diagnostic and therapeutical approaches in spinal cord pathologies.

Differential influence of different hepatitis viruses on quality of life in HIV positive patients

HIV-infected individuals are frequently co-infected with different hepatitis viruses. HCV has been associated with impaired quality of life in non-HIV infected patients. Little is known concerning the quality of life in HIV-infected individuals in relation to the different viral co-infections. -

PATIENTS AND METHODS

We investigated 250 patients who have answered HIV-SELT and EuroQoL (EQ-5D) questionnaires assessing quality of life. Data on HBsAg, anti-HBc, anti-HCV, and GBV-C-RNA were available for 191, 188, 189, 98 patients, respectively. HCV-RNA was tested in 33 of 35 anti-HCV positive patients. -

RESULTS

There was no difference in quality of life in relation to active or past HBV-infection defined by HBsAg (n = 15) and anti-HBc in the absence of HBsAg (n = 84), respectively, for both overall HIV-SELT (p = 0.66, and p = 0.43, respectively) and visual EQ-5D (p = 0.93 and p = 0.64, respectively). However, anti-HCV positivity (n = 35) was associated with significantly impaired quality of life (HIV-SELT overall p<0.001). Importantly, no difference was found in relation to HCV-viraemia in anti-HCV positive patients (p = 0.77). In multivariate analysis anti-HCV positivity, employment status, HIV viral load and GBV-C were relevant to quality of life, with GBV-C being beneficial and HCV being negative. -

CONCLUSIONS

While HBV seems to play no role concerning quality of live in HIV-infected patients, the flavi-viruses HCV and GBV-C display opposing influence on quality of life. As quality of life was similarly impaired in HCV-viraemic and HCV-non-viraemic anti-HCV positive patients but better in GBV-C viraemic patients, this should be taken into account in the indication case of planned interferon therapy.

Evaluation of single nucleotide polymorphisms in the phosphodiesterase 4D gene (PDE4D) and their association with ischaemic stroke in a large German cohort

Genetic fine mapping of the first locus identified for genetically complex forms of stroke, STRK1 (which has been mapped to chromosome 5q12 in Icelandic families), has identified the phosphodiesterase 4D gene (PDE4D) gene as a good candidate gene. Association analysis of single nucleotide polymorphisms (SNPs) in the PDE4D gene in an Icelandic stroke cohort demonstrated genetic association between six SNPs in the 5' region of PDE4D and ischaemic stroke. The present study aimed to test whether the same six SNPs in PDE4D were also associated with stroke in a large stroke cohort from northern Germany (stroke patients with acute completed ischaemic stroke: n = 1181; population based controls: n = 1569). None of the six SNPs showed significant association with ischaemic stroke in the whole stroke sample before and after adjustment for conventional stroke risk factors (age, sex, hypertension, diabetes, and hypercholesterolaemia). Haplotype analysis did also not reveal any significant association. Marginally positive statistical measures of association in the subgroup with cardioembolic stroke did not remain significant after correction for multiple testing. In conclusion, this study was unable to demonstrate an association between the six SNPs which had showed significant single marker association with stroke in the Icelandic stroke cohort and ischaemic stroke in a large German cohort.

Psychological effects of (S)-ketamine and N,N-dimethyltryptamine (DMT): a double-blind, cross-over study in healthy volunteers

INTRODUCTION

Pharmacological challenges with hallucinogens are used as models for psychosis in experimental research. The state induced by glutamate antagonists such as phencyclidine (PCP) is often considered as a more appropriate model of psychosis than the state induced by serotonergic hallucinogens such as lysergic acid diethylamide (LSD), psilocybin and N,N-dimethyltryptamine (DMT). However, so far, the psychological profiles of the two types of hallucinogenic drugs have never been studied directly in an experimental within-subject design.

METHODS

Fifteen healthy volunteers were included in a double-blind, cross-over study with two doses of the serotonin 5-HT2A agonist DMT and the glutamate N-methyl-D-aspartate (NMDA) antagonist (S)-ketamine.

RESULTS

Data are reported for nine subjects who completed both experimental days with both doses of the two drugs. The intensity of global psychological effects was similar for DMT and (S)-ketamine. However, phenomena resembling positive symptoms of schizophrenia, particularly positive formal thought disorder and inappropriate affect, were stronger after DMT. Phenomena resembling negative symptoms of schizophrenia, attention deficits, body perception disturbances and catatonia-like motor phenomena were stronger after (S)-ketamine.

DISCUSSION

The present study suggests that the NMDA antagonist model of psychosis is not overall superior to the serotonin 5-HT2A agonist model. Rather, the two classes of drugs tend to model different aspects or types of schizophrenia. The NMDA antagonist state may be an appropriate model for psychoses with prominent negative and possibly also catatonic features, while the 5-HT2A agonist state may be a better model for psychoses of the paranoid type.

Antimicrobial-finished textile three-dimensional structures

This paper describes the possibilities of antimicrobial finishing of three-dimensional spacer fabrics and its applications, and gives information about the different effects. A research project of the Textilforschungsinstitut Thüringen-Vogtland Greiz is presented in which medical shoe insoles, based on specially manufactured three-dimensional spacer fabrics, made of permanently effective antimicrobial yarns were used for interesting and functional textile products. Furthermore, work of the research institute Forschungsinstitut für Leder und Kunststoffbahnen Freiberg is presented which describes the silver-coating process and application of textile materials using antimicrobial substances. The chemical and mechanical stability is investigated, and proof of the effectiveness is supplied. The results show that in the three-dimensional spacer fabrics both - antimicrobial yarn materials and thin silver films with antimicrobial substances - can achieve an antimicrobial effect, even in low quantities.

Thymidine Analogue Mutation Profiles: Factors Associated with Acquiring Specific Profiles and their Impact on the Virological Response to Therapy

Background

Studies have suggested that HIV-1 may develop thymidine analogue mutations (TAMs) by one of two distinct pathways – the TAM1 pathway (including mutations 41L, 210W and 215Y) or the TAM2 pathway (including mutations 67N, 70R and 219E/Q) – under the pressure of a not fully suppressive thymidine-analogue-containing regimen.

Methods

Frozen plasma samples stored in the EuroSIDA repository were selected and sent to two central laboratories for genotypic analysis. We considered 733 patients with at least one genotypic test showing ≥1 TAMs (the first of these tests in chronological order was used). TAM1 and TAM2 genotypic profiles were defined in accordance with previous literature. Statistical modelling involved logistic regression and linear regression analysis for censored data.

Results

The observed frequencies of patterns classifiable as TAM1 or TAM2 profiles were markedly higher than the probabilities of falling into these classifications by chance alone. The chance of detecting a TAM2 profile increased by 25% per additional year of exposure to zidovudine. We found that mutations 67N and 184V were not associated with a particular TAM profile. In the presence of TAM2 profiles, the adjusted mean difference in the 6-month viral reduction was 0.96 log10 copies/ml (95% confidence interval: 0.20; 1.73) higher in patients who started stavudine-containing regimens instead of zidovudine-containing regimens.

Conclusions

This study provides evidence that the suggested TAM clustering is a real phenomenon and that it may be driven by which thymidine analogue the patients has used. In patients with TAM2-resistant viruses, stavudine appears to retain greater viral activity than zidovudine.

Matter wave diffraction from an inclined transmission grating: searching for the elusive 4He trimer Efimov state

The size of the helium trimer is determined by diffracting a beam of 4He clusters from a 100 nm period grating inclined by 21 degrees. Because of the bar thickness the projected slit width is roughly halved to 27 nm, increasing the sensitivity to the trimer size. The peak intensities measured out to the eighth order are evaluated via a few-body scattering theory. The trimer pair distance is found to be (r) = 1.1(+0.4)(-0.5) nm in agreement with predictions for the ground state. No evidence for a significant amount of Efimov trimers is found. Their concentration is estimated to be under 6%, less than expected.

GB virus C infection and quality of life in HIV-positive patients

It was recently shown that GBV-C infection is associated with prolonged survival of HIV-infected individuals. The GB virus C is the closest known relative of hepatitis C virus in man. The latter has been associated with significant impairment in quality of life, independent from the associated liver disease. We were thus interested in the impact of GB virus C infection on quality of life in HIV-infected individuals. We retrospectively analyzed a cohort of HIV-positive patients who previously answered the 'HIV-SELT' and the 'EQ-5D' questionnaires assessing quality of life and for whom data on GB virus C RNA status were available. In this study we identified no adverse effect of GB virus C on quality of life, but, in contrast, GB virus C viraemic patients showed better quality of life in all parameters for the scores in comparison to GB virus C-negative HIV-infected patients. HIV-positive patients with a GB virus C infection showed superior quality of life. These data further support the favourable course of HIV disease in GB virus C-positive patients.