Demonstrating Agreement between Radio and Fluorescence Measurements of the Depth of Maximum of Extensive Air Showers at the Pierre Auger Observatory

We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.

Limits to Gauge Coupling in the Dark Sector Set by the Nonobservation of Instanton-Induced Decay of Super-Heavy Dark Matter in the Pierre Auger Observatory Data

Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α_{X}≲0.09, for 10^{9}≲M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}≳3×10^{13}  GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.

Biological Impact on the Stability and Reliability of Acute and Chronic Platinum based Thin Film Neural Interfaces in Vivo

Reliability, stability and biocompatibility of an im-plant are the keys to transferring a preclinical study into the re-ality of clinical applications for diagnostics and therapy of pa-tients. Amongst the smallest and most critical components of neuroprostheses are the neural interfaces to the tissue. These could be seen as the most functional and yet most sensitive parts to connect to and interact with the nervous system. Thin film systems in the submicro- to nanometers range with a high num-ber of channels record biological signals and excite nerves aspiring high spatial sensitivity at the scale of few neurons. The im-pairments of the technical material caused by the harsh environ-ment of the human body and potential damage to the tissue by the foreign body state the greatest obstacle to overcome. Here, we present an analysis on impact of acutely and chronically im-planted subdural electrocorticography (ECoG) recording arrays on the neural tissue and the accompanied material failure mechanisms of the thin film neural interfaces in vivo.

Plasma concentration of proneurotensin and prediction of cause-specific mortality in a middle aged cohort during long-term follow-up

Purpose

To examine the prediction of proneurotensin (Pro-NT) on total and cause-specific mortality in a middle-aged cohort.

Methods

In the population-based middle-aged cohort (n=4632 participants, mean age 57 years) of the Malmo Diet and Cancer (MDC) study, Pro-NT was assessed and total- as well as cause-specific mortality were studied. Main cause of death were based on the International Classification of Diseases (ICD). Assessments were done using Cox proportional hazards models adjusted for age and sex.

Results

During a mean follow-up of 20±3 years, 950 men and 956 women died. There was a significantly increased risk of total mortality in subjects belonging to quartile 4 of Pro-NT (Pro-NT ≥149 pmol/L) compared with quartiles 1–3 (Pro-NT &lt;149 pmol/L), hazard ratio (HR) of 1.29 (95% confidence interval [CI] 1.17–1.42; P&lt;0.001) after adjustment for age and sex. No significant interaction was observed between Pro-NT and gender on total mortality. Individuals within quartile 4 vs. quartiles 1–3 had a HR of 1.41 (95% CI 1.18–1.68; P&lt;0.001) for death due to cardiovascular diseases (n=595/4632), 2.53 (95% CI 1.37–4.67; P=0.003) due to digestive tract diseases (n=42/4632), 1.62 (95% CI 1.04–2.52; P=0.032) due to mental and behavioural diseases (n=90/4632), and 1.91 (95% CI 1.15–3.19; P=0.013) due to unspecific causes of death (n=64/4632). No significant relationships between Pro-NT and deaths due to cancer, infections, neurological or other causes were observed. Adjustments for cardiovascular risk factors only marginally changed these results.

Conclusions

Pro-NT is a predictor of total mortality and the increased risk is driven by deaths due to cardiovascular- digestive tract- mental and behavioural diseases, as well as deaths attributed to unspecific causes.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Knut and Alice Wallenberg Foundationthe Swedish Heart and Lung Foundation.

The impact of site-specific digital histology signatures on deep learning model accuracy and bias

The Cancer Genome Atlas (TCGA) is one of the largest biorepositories of digital histology. Deep learning (DL) models have been trained on TCGA to predict numerous features directly from histology, including survival, gene expression patterns, and driver mutations. However, we demonstrate that these features vary substantially across tissue submitting sites in TCGA for over 3,000 patients with six cancer subtypes. Additionally, we show that histologic image differences between submitting sites can easily be identified with DL. Site detection remains possible despite commonly used color normalization and augmentation methods, and we quantify the image characteristics constituting this site-specific digital histology signature. We demonstrate that these site-specific signatures lead to biased accuracy for prediction of features including survival, genomic mutations, and tumor stage. Furthermore, ethnicity can also be inferred from site-specific signatures, which must be accounted for to ensure equitable application of DL. These site-specific signatures can lead to overoptimistic estimates of model performance, and we propose a quadratic programming method that abrogates this bias by ensuring models are not trained and validated on samples from the same site.

Measurement of the Fluctuations in the Number of Muons in Extensive Air Showers with the Pierre Auger Observatory

We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower simulations. This observation provides new insights into the origin of the previously reported deficit of muons in air shower simulations and constrains models of hadronic interactions at ultrahigh energies. Our measurement is compatible with the muon deficit originating from small deviations in the predictions from hadronic interaction models of particle production that accumulate as the showers develop.

Downregulation of growth hormone in postural orthostatic tachycardia syndrome: insights from the SYSTEMA cohort

Background

Postural orthostatic tachycardia syndrome (POTS) is a variant of cardiovascular autonomic disorder occurring predominantly in young women. POTS is characterized by an excessive heart rate increase when assuming upright posture accompanied by symptoms of orthostatic intolerance. The pathophysiology of POTS has not been fully established and is believed to be multifactorial.

Purpose

We aimed to investigate the alterations in circulating growth hormone level in POTS.

Methods

We conducted an age-matched case-control study enrolling 42 patients with POTS (age 31±9 years; 36 women) verified by positive head-up tilt testing and cardiovascular autonomic tests, and 46 controls (32±9 years; 35 women) with negative active standing test and no history of syncope, orthostatic intolerance and endocrine disease. We measured plasma levels of growth hormone using a high-sensitivity chemiluminescence immunoassay in relation to presence of POTS diagnosis. All study participants completed the validated Orthostatic Hypotension Questionnaire (OHQ), consisting of two components: the symptoms assessment scale (OHSA) and daily activity scale (OHDAS) to evaluate the burden of symptoms. We applied standard statistical tests for group differences. Growth hormone values were log-transformed and standardized before the group comparison.

Results

POTS patients had significantly lower plasma levels of growth hormone (ng/mL) (median=0.53, IQR, 0.10–2.83 vs. median=2.33, IQR, 0.26–7.2, p=0.04) than controls. Levels of growth hormone were reversely related to OHDAS (p=0.049) among POTS patients. Supine heart rate was significantly higher in POTS patients (69.0±11.1 beats/min vs. 63.3±10.8 beats/min, p=0.02), as well as diastolic blood pressure (72.9±9.1 mmHg vs. 69.0±8.5 mmHg, p=0.04). We observed no significant difference in supine systolic blood pressure (116.6±13.3 mmHg vs. 115.2±10.0 mmHg, p=0.60). POTS patients had a significantly higher composite OHQ score than controls (60.0±18.6 vs. 4.2±7.5, p&lt;0.001), as well as OHSA (36.2±10.0 vs. 3.6±6.4, p&lt;0.001) and OHDAS (23.8±9.7 vs. 0.6±1.3, p&lt;0.001).

Conclusion(s)

Our study shows that patients with POTS have significantly reduced plasma levels of circulating growth hormone. Lower growth hormone levels among POTS patients are associated with increased impairment of daily life activities. Further studies are necessary to confirm our findings in the independent populations and explain the mechanisms behind this alteration.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Crafoord Foundation, Swedish Heart and Lung Foundation

Scalable 30 fs laser source with 530 W average power

We present a power-scalable laser source with 30 fs pulse duration, 530 W average power at 500 kHz repetition rate, and beam quality M²<1.2. The compact and efficient setup consists of ytterbium-based Innoslab amplifiers and subsequent nonlinear pulse compression with an argon-filled Herriott cell.

High-flux ultrafast extreme-ultraviolet photoemission spectroscopy at 18.4 MHz pulse repetition rate

Laser-dressed photoelectron spectroscopy, employing extreme-ultraviolet attosecond pulses obtained by femtosecond-laser-driven high-order harmonic generation, grants access to atomic-scale electron dynamics. Limited by space charge effects determining the admissible number of photoelectrons ejected during each laser pulse, multidimensional (i.e. spatially or angle-resolved) attosecond photoelectron spectroscopy of solids and nanostructures requires high-photon-energy, broadband high harmonic sources operating at high repetition rates. Here, we present a high-conversion-efficiency, 18.4-MHz-repetition-rate cavity-enhanced high harmonic source emitting 5 × 105 photons per pulse in the 25-to-60-eV range, releasing 1 × 1010 photoelectrons per second from a 10-µm-diameter spot on tungsten, at space charge distortions of only a few tens of meV. Broadband, time-of-flight photoelectron detection with nearly 100% temporal duty cycle evidences a count rate improvement between two and three orders of magnitude over state-of-the-art attosecond photoelectron spectroscopy experiments under identical space charge conditions. The measurement time reduction and the photon energy scalability render this technology viable for next-generation, high-repetition-rate, multidimensional attosecond metrology.

Laryngotracheal Involvement in Systemic Light Chain Amyloidosis

Laryngotracheal amyloid deposition is an uncommon manifestation of systemic light chain amyloidosis. Diagnostic imaging, such as CT, is useful for suggesting the possibility of amyloidosis and delineating the extent of the lesions for surgical management; however, the diagnosis is confirmed with the histologic finding of amorphous eosinophilic material which stains positively for Congo red and may show apple green birefringence on polarization. These features are exemplified in this sine qua non radiology-pathology correlation article.

Probabilistic Algorithms and the Interactive Museum Tour-Guide Robot Minerva

This paper describes Minerva, an interactive tour-guide robot that was successfully deployed in a Smithsonian museum. Minerva’s software is pervasively probabilistic, relying on explicit representations of uncertainty in perception and control. During 2 weeks of operation, the robot interacted with thousands of people, both in the museum and through the Web, traversing more than 44 km at speeds of up to 163 cm/sec in the unmodified museum.

Hairy Polyp of the Nasopharynx Arising from the Eustachian Tube

Hairy polyps of the nasopharynx display characteristic radiological imaging findings, including the presence of fat in the polypoid mass. Furthermore, diagnostic imaging is useful for delineating the site of origin of these lesions, which can facilitate surgical planning. For instance hairy polyps that arise from the right Eustachian tube can be amputated via a trans-nasal approach with endoscopy, but may necessitate a two stage approach in order to avoid injury to critical structures, such as the internal carotid artery. On histology, hairy polyps comprise an outer keratinizing squamous epithelium with adnexal tissue, including hair follicles, and central fibroadipose and cartilaginous tissue. These features are exemplified in this sine qua non radiology-pathology correlation article.

Seroprevalence of HSV-1 and HSV-2 antibodies in Canadian women screened for enrolment in a herpes simplex virus vaccine trial

Herpes simplex virus 1 and 2 (HSV-1 and HSV-2) infections continue to be among the most common and unrecognized sexually transmitted infections in the world. Although treatable, HSV-1 and HSV-2 infections remain incurable. Hence, there is interest in the development of a vaccine to prevent genital herpes. As part of a multicentre, randomized, placebo-controlled trial to test such a vaccine, healthy women 18-30 years were enrolled as volunteers in several Canadian centres between 2005 and 2007. This study reports the seroprevalence of HSV-1 and HSV-2 antibodies in this group. A total of 2694 adult female volunteers in Canada with no known history of herpes simplex were screened for HSV antibodies using Western blot assay (the gold standard for diagnosis of HSV) for potential participation in a randomized, double-blind efficacy field trial of a herpes simplex vaccine. This trial provides a unique opportunity to examine the prevalence of antibodies to HSV-1 and of antibodies to HSV-2 in women with no known history of herpes simplex infection. The prevalence of antibodies to HSV-1 and to HSV-2 is compared with that found in previous Canadian studies that focused on a more general population. The overall seroprevalence of antibody to HSV-1 was 43%; that of HSV-2 was 2.5% and seropositivity to both was 2%. The prevalence of antibody to both HSV-1 and to HSV-2 increased with age. Seronegativity to both HSV-1 and HSV-2 was 56% in participating centres with populations under 250,000 and 46% in participating centres with populations over 250,000. Significant racial differences in seropositivity to HSV-1 and to HSV-2 were noted. The likelihood of participants being seropositive to HSV-1 and to HSV-2 was found to increase with age and to positively correlate with the population of the city in which they resided. Hypotheses are proposed to account for differences in racial seropositivity to HSV-1 and to HSV-2.

Technology and Performance of TFA (Thin Film on ASIC-Sensors

A TFA image sensor consists of an amorphous silicon based multilayer structure on top of a crystalline ASIC. The Multilayer acts as the optical detector, whereas the ASIC performs analog or digital signal processing for each individual pixel. Depending on the operation Mode, the dynamic range of the detector exceeds the performance of conventional CCDs by far. Pixel electronics which is adapted to the requirements of the detector can thereby maximize the dynamic range of the complete sensor array. Crosstalk among adjacent pixels can be eliminated by technological or electronic Means.

Antiretroviral therapy and preterm delivery-a pooled analysis of data from the United States and Europe

OBJECTIVE

 To investigate reported differences in the association between highly active antiretroviral therapy (HAART) in pregnancy and the risk of preterm delivery among HIV-infected women.

DESIGN

  Combined analysis of data from three observational studies.

SETTING

 USA and Europe.

POPULATION

  A total of 19, 585 singleton infants born to HIV-infected women, 1990-2006.

METHODS

  Data from the Pediatric Spectrum of HIV Disease project (PSD), a US monitoring study, the European Collaborative Study (ECS), a consented cohort study, and the National Study of HIV in Pregnancy and Childhood (NSHPC), the United Kingdom and Ireland surveillance study.

MAIN OUTCOME MEASURE

  Preterm delivery rate (<37 weeks of gestation).

RESULTS

  Compared with monotherapy, HAART was associated with increased preterm delivery risk in the ECS (adjusted odds ratio [AOR] 2.40, 95% CI 1.49-3.86) and NSHPC (AOR 1.43, 95% CI 1.10-1.86), but not in the PSD (AOR 0.92, 95% CI 0.67-1.26), after adjusting for relevant covariates. Because of heterogeneity, data were not pooled for this comparison, but heterogeneity disappeared when HAART was compared with dual therapy (P = 0.26). In a pooled analysis, HAART was associated with 1.5-fold increased odds of preterm delivery compared with dual therapy (95% CI 1.19-1.87, P=0.001), after adjusting for covariates.

CONCLUSIONS

  Heterogeneity in the association between HAART and preterm delivery was not explained by study design, adjustment for confounders or a standard analytical approach, but may have been the result of substantial differences in populations and data collected. The pooled analysis comparing HAART with dual therapy showed an increased risk of preterm delivery associated with HAART.

An integrative genomics screen uncovers ncRNA T-UCR functions in neuroblastoma tumours

Different classes of non-coding RNAs, including microRNAs, have recently been implicated in the process of tumourigenesis. In this study, we examined the expression and putative functions of a novel class of non-coding RNAs known as transcribed ultraconserved regions (T-UCRs) in neuroblastoma. Genome-wide expression profiling revealed correlations between specific T-UCR expression levels and important clinicogenetic parameters such as MYCN amplification status. A functional genomics approach based on the integration of multi-level transcriptome data was adapted to gain insights into T-UCR functions. Assignments of T-UCRs to cellular processes such as TP53 response, differentiation and proliferation were verified using various cellular model systems. For the first time, our results define a T-UCR expression landscape in neuroblastoma and suggest widespread T-UCR involvement in diverse cellular processes that are deregulated in the process of tumourigenesis.

Atorvastatin interferes with activation of human CD4(+) T cells via inhibition of small guanosine triphosphatase (GTPase) activity and caspase-independent apoptosis

Although a beneficial effect of hydroxy-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, i.e. statins, on cell-mediated immunity has been suggested in vivo and in vitro, little is known about the molecular and biochemical events by which statins inhibit T cell proliferation. To address this question, we investigated the effects of atorvastatin (AT) on intracellular cytokine production, T cell activation markers, cell cycle progression and apoptosis in human CD4(+) T cells. AT did not influence intracellular cytokine production after short-term stimulation of whole blood with phorbol myristate acetate (PMA)/ionomycin or superantigen (SEB). In contrast, AT influenced CD45RA to RO switching dose-dependently, as well as CD25 expression, and caused cell cycle arrest in the G1 phase after long-term T cell stimulation. This occurred in conjunction with a reduced expression of cyclin-dependent kinases 2 and 4 and p21(wav1/cip1) and was paralleled by an increased protein expression of p27(kip1). In addition to G1 arrest, increased apoptosis was observed in AT-treated cells. In line with this, the expression of Bcl-xl and pBad were decreased by AT. Apoptosis was independent of caspases 3 and 9 activation. The inhibitory effect of AT on T cell proliferation could be overcome by addition of mevalonic acid or geranylgeranyl pyrophosphate, but not by farnesyl pyrophosphate or squalen, suggesting reduced protein prenylation. Activation of Rho, Rac and Ras were strongly reduced in AT-treated T cells, suggesting that impaired geranylation of these molecules might underlie the inhibitory effect of AT on T cell proliferation.

Heterogeneity in lipopolysaccharide responsiveness of endothelial cells identified by gene expression profiling: role of transcription factors

Interindividual differences of endothelial cells in response to endotoxins might contribute to the diversity in clinical outcome among septic patients. The present study was conducted to test the hypothesis that endothelial cells (EC) with high and low proinflammatory potential exist and to dissect the molecular basis underlying this phenomenon. Thirty human umbilical vein endothelial cell (HUVEC) lines were stimulated for 24 h with lipopolysaccharide (LPS) and screened for interleukin (IL)-8 production. Based on IL-8 production five low and five high producers, tentatively called types I and II responders, respectively, were selected for genome-wide gene expression profiling. From the 74 genes that were modulated by LPS in all type II responders, 33 genes were not influenced in type I responders. Among the 41 genes that were increased in both responders, 17 were expressed significantly stronger in type II responders. Apart from IL-8, significant differences in the expression of proinflammatory related genes between types I and II responders were found for adhesion molecules [intercellular adhesion molecule (ICAM-1), E-selectin)], chemokines [monocyte chemoattractant protein (MCP-1), granulocyte chemotactic protein (GCP-2)], cytokines (IL-6) and the transcription factor CCAAT/enhancer binding protein-delta (C/EBP-delta). Type I responders also displayed a low response towards tumour necrosis factor (TNF)-alpha. In general, maximal activation of nuclear factor (NF)-kappaB was achieved in type I responders at higher concentrations of LPS compared to type II responders. In the present study we demonstrate that LPS-mediated gene expression differs quantitatively and qualitatively in types I and II responders. Our results suggest a pivotal role for common transcription factors as a low inflammatory response was also observed after TNF-alpha stimulation. Further studies are required to elucidate the relevance of these findings in terms of clinical outcome in septic patients.

Subchronic alpha- and beta-adrenergic regulation of cardiac gap junction protein expression

Gap junction channels are essential for intercellular electrical communication in the heart. The most important cardiac gap junction proteins are connexin43 (predominantly) (Cx43), connexin40 (Cx40), and in early developmental stages connexin45. Since catecholamines play an important role in cardiac (patho)physiology, we wanted to elucidate whether catecholamines may affect expression of Cx43 and Cx40. Cultured neonatal rat cardiomyocytes were exposed for 24 h to increasing concentrations of noradrenaline (1-10000 nM) (physiological agonist at alpha and beta-adrenoceptors), resulting in significantly increased Cx43-expression, while Cx40 was unaffected. In further experiments cells were incubated with either phenylephrine (alpha-adrenergic agonist) or isoproterenol (beta-adrenergic agonist) (0.1-1000 nM) for 24 h. Both catecholamines lead to a concentration-dependent increase in Cx43 protein and mRNA expression (EC50: 10-20 nM). Inhibition experiments showed that the phenylephrine effect was transduced via PKC, while the isoproterenol effect was mediated by PKA. Dual whole-cell voltage clamp demonstrated that increased Cx43-expression was accompanied by significant increases in gap junction current. In additional in vivo experiments, adult rats were subjected to 24-h infusion of isoproterenol or phenylephrine showing again significant increase in Cx43 but not Cx40. Adrenergic stimulation of cardiomyocytes can enhance Cx43 expression thereby increasing cellular coupling, indicating a possible role for catecholamines in the regulation of cardiac gap junction expression in cardiac disease.

Effekte von Dopamin auf die zelluläre und humorale Immunantwort von Patienten mit Sepsis

In vitro and in vivo studies have demonstrated that apart from its hemodynamic action dopamine can modulate immune responses. Dopamine reduces the synthesis of proinflammatory and induces the synthesis of anti-inflammatory mediators. Dopamine inhibits neurohormone synthesis, lymphocyte proliferation and platelet aggregation. It reduces the phagocytic activity of neutrophils and induces apoptosis. Particularly with regard to sepsis, where high serum dopamine levels are reached by enhanced endogenous production, exogenous application and impaired clearance, this immunomodulation may have a clinical impact. This review summarizes dopamine-mediated immunomodulating effects to advance the knowledge regarding dopamine as an immune regulator under septic conditions.

Spike timing in CA3 pyramidal cells during behavior: implications for synaptic transmission

Spike timing is thought to be an important mechanism for transmitting information in the CNS. Recent studies have emphasized millisecond precision in spike timing to allow temporal summation of rapid synaptic signals. However, spike timing over slower time scales could also be important, through mechanisms including activity-dependent synaptic plasticity or temporal summation of slow postsynaptic potentials (PSPs) such as those mediated by kainate receptors. To determine the extent to which these slower mechanisms contribute to information processing, it is first necessary to understand the properties of behaviorally relevant spike timing over this slow time scale. In this study, we examine the activity of CA3 pyramidal cells during the performance of a complex behavioral task in rats. Sustained firing rates vary over a wide range, and the firing rate of a cell is poorly correlated with the behavioral cues to which the cell responds. Nonrandom interactions between successive spikes can last for several seconds, but the nonrandom distribution of interspike intervals (ISIs) can account for the majority of nonrandom multi-spike patterns. During a stimulus, cellular responses are temporally complex, causing a shift in spike timing that favors intermediate ISIs over short and long ISIs. Response discrimination between related stimuli occurs through changes in both response time-course and response intensity. Precise synchrony between cells is limited, but loosely correlated firing between cells is common. This study indicates that spike timing is regulated over long time scales and suggests that slow synaptic mechanisms could play a substantial role in information processing in the CNS.

Large-scale analysis of 73 329 physcomitrella plants transformed with different gene disruption libraries: production parameters and mutant phenotypes

Gene targeting in the moss Physcomitrella patens has created a new platform for plant functional genomics. We produced a mutant collection of 73 329 Physcomitrella plants and evaluated the phenotype of each transformant in comparison to wild type Physcomitrella. Production parameters and morphological changes in 16 categories, such as plant structure, colour, coverage with gametophores, cell shape, etc., were listed and all data were compiled in a database (mossDB). Our mutant collection consists of at least 1804 auxotrophic mutants which showed growth defects on minimal Knop medium but were rescued on supplemented medium. 8129 haploid and 11 068 polyploid transformants had morphological alterations. 9 % of the haploid transformants had deviations in the leaf shape, 7 % developed less gametophores or had a different leaf cell shape. Other morphological deviations in plant structure, colour, and uniformity of leaves on a moss colony were less frequently observed. Preculture conditions of the plant material and the cDNA library (representing genes from either protonema, gametophore or sporophyte tissue) used to transform Physcomitrella had an effect on the number of transformants per transformation. We found correlations between ploidy level and plant morphology and growth rate on Knop medium. In haploid transformants correlations between the percentage of plants with specific phenotypes and the cDNA library used for transformation were detected. The number of different cDNAs present during transformation had no effect on the number of transformants per transformation, but it had an effect on the overall percentage of plants with phenotypic deviations. We conclude that by linking incoming molecular, proteome, and metabolome data of the transformants in the future, the database mossDB will be a valuable biological resource for systems biology.

Developmental outcome of the use of etamsylate for prevention of periventricular haemorrhage in a randomised controlled trial

OBJECTIVE

To compare neurodevelopmental outcome of survivors of the multicentre trial of etamsylate (the iRNN for ethamsylate) for prevention of periventricular haemorrhage in very low birthweight infants.

DESIGN

Double blind, single observer, prospective follow up of placebo controlled study.

SETTING

Six neonatal intensive care units in the United Kingdom. Neurodevelopmental outcome was assessed in health premises or children's homes.

SUBJECTS

268 of 276 survivors of the original study were seen between 3.5 and 4.2 years of age. All were inborn and weighed 1500 g or less at birth.

INTERVENTION

Etamsylate 12.5 mg/kg or placebo six hourly from within one hour of delivery for four days.

MAIN OUTCOME MEASURES

McCarthy scales of children's abilities, standardised neurological examination, full physical examination, functional assessment, seven letter Stycar vision test, and audiometry.

RESULTS

There was no difference between the groups in neuromotor outcome (cerebral palsy) or in the general cognitive index (GCI) of the McCarthy scales (mean GCI was 93.3 for the etamsylate group (n = 133) and 89.7 for the placebo group (n = 131); p = 0.10). There were more children with GCI < 70 (9 v 19; p = 0.047) or </= 50 (3 v 11; p = 0.03) in the placebo group. Fewer children in the etamsylate group had squints (17 v 30; p = 0.042) or required surgery for patent ductus arteriosus (1 v 8; p = 0.036).

CONCLUSIONS

Etamsylate was not associated with a reduction in cerebral palsy. Severe cognitive impairment was reduced, but more children died and the improvement may be because fewer survived with low GCI.

Newborn screening for biotinidase deficiency in Brazil: biochemical and molecular characterizations

Biotinidase deficiency is an inherited metabolic disorder characterized by neurological and cutaneous symptoms. Fortunately, it can be treated and the symptoms prevented by oral administration of the vitamin biotin. Using dried blood-soaked filter paper cards, biotinidase activity was determined in the sera of 225,136 newborns in Brazil. Mutation analysis performed on DNA from 21 babies with low serum biotinidase activity confirmed that 3 had profound biotinidase deficiency (less than 10% of mean normal sera biotinidase activity), 10 had partial biotinidase deficiency (10 to 30% of mean normal serum activity), 1 was homozygous for partial biotinidase deficiency, 4 were heterozygous for either profound or partial deficiency, and 3 were normal. Variability in serum enzyme activities and discrepancies with mutation analyses were probably due to inappropriate handling and storage of samples sent to the laboratory. Obtaining an appropriate control serum at the same time as that of the suspected child will undoubtedly decrease the false-positive rate (0.09%). Mutation analysis can be used to confirm the genotype of these children. The estimated incidence of biotinidase deficiency in Brazil is about 1 in 9,000, higher than in most other countries. Screening and treatment of biotinidase deficiency are effective and warranted. These results strongly suggest that biotinidase deficiency should be included in the newborn mass screening program of Brazil.

High throughput cryopreservation of 140,000 Physcomitrella patens mutants

A high throughput protocol was established to preserve 140,000 mutants of a moss, Physcomitrella patens, a model plant for functional genomics studies, over liquid nitrogen. Regarding the reliable long-term storage of diverse mutant phenotypes, as well as time and cost effectiveness, each working step was optimized: 1) plant preparation, 2) freezing regime, cryogenic conditions, 3) regrowth after thawing. A prerequisite for maximum regrowth was a 1-week preculture of chopped plant material on a supplemented medium prior to freezing. Cryo vials as preculture vessels resulted in identical regrowth rates, compared to petri dishes. The cryo vial type had a significant influence on regrowth rates. A cooling rate of - 1 degrees C/min down to - 35 degrees C with a 10 min holding time before transferring plants to - 152 degrees C was the most suitable freezing regime. This protocol allows a cryopreservation of 1100 plants during a 5-day working week, practicable by one person. For more than 650 cryopreserved mutants a maximum regrowth rate of 100 % was obtained, independently of mutant phenotypes.

Fractalkine is not a major chemoattractant for the migration of neutrophils across microvascular endothelium

Inflammatory responses during sepsis are determined by leucocyte recruitment into inflamed tissues. Both chemokines and adhesion molecules are believed to be involved in this process. As fractalkine exists as transmembrane protein with cell adhesion properties and as soluble chemotactic factor, the present study was conducted to study the role of fractalkine, produced by microvascular and macrovascular endothelial cells, in neutrophil recruitment. Lung microvascular endothelial cells (LMVECs) stimulated with lipopolysaccharide, tumour necrosis factor-alpha or interleukin-1 (IL-1) produced much more fractalkine compared with the macrovascular human umbilical vein endothelial cells (HUVECs). No differences were found between microvascular endothelial cells of different organs. Chemotactic activity in supernatants was significantly stronger in stimulated LMVEC when compared with HUVEC. Although recombinant fractalkine induced migration of neutrophils, IL-8 and monocyte chemoattractant protein-1 were found to be more strictly required. In vivo fractalkine was strongly upregulated in septic lung and kidney. Our data suggest that fractalkine production per se does not explain the preference for inflammation in the lung of septic patients.

Inhibition of LPS-induced chemokine production in human lung endothelial cells by lipid conjugates anchored to the membrane

1. In acute respiratory distress syndrome (ARDS) induced by endotoxins, a high production of inflammatory mediators by microvascular lung endothelial cells (LMVEC) can be observed. Activation of cells by endotoxins may result in elevated secretion of phospholipase A(2) (sPLA(2)) which is thought to contribute to tissue damage. The present study was undertaken to investigate the role of sPLA(2) in chemokine production in human lung microvascular endothelial cells (LMVEC) stimulated with the endotoxins lipopolysaccharide (LPS) and lipoteichoic acid (LTA). In particular, we investigated the effects of sPLA(2) inhibitors, specifically, the extracellular PLA(2) inhibitors (ExPLIs), composed of N-derivatized phosphatidyl-ethanolamine linked to polymeric carriers, and LY311727, a specific inhibitor of non-pancreatic sPLA(2). 2. ExPLIs markedly inhibited LPS and LTA induced production and mRNA expression of the neutrophile attracting chemokines IL-8, Gro-alpha and ENA-78, as well as of the adhesion molecules ICAM-1 and E-selectin. Concomitantly, ExPLIs inhibited the LPS-induced activation of NF-kappaB by LPS but not its activation by TNF-alpha or IL-1. 3. Endotoxin mediated chemokine production in LMVEC seems not to involve PLA(2) activity, since LPS stimulation was not associated with activation of intracellular or secreted PLA(2). It therefore seems that the inhibitory effect of the ExPLIs was not due to their PLA(2) inhibiting capacity. This was supported by the finding that the LPS-induced chemokine production was not affected by the selective sPLA(2) inhibitor LY311727. 4. It is proposed that the ExPLIs may be considered a prototype of potent suppressors of specific endotoxin-induced inflammatory responses, with potential implications for the therapy of subsequent severe inflammation.

Median nerve evoked responses: stimulation modalities for midlatency cortical components

PURPOSE

Median nerve somatosensory evoked responses (MnSSER) are frequently used clinically and scientifically. However, the stimulus-response interrelationship has not been documented for the midlatency components. Therefore we investigated the spinal and cortical midlatency MnSSER, to document the effect of different stimulus intensities.

METHODS

Spinal and midlatency MnSSER were recorded following percutaneous electrical stimulation of the median nerve at the wrist in 32 neurological healthy females. Three different stimulation intensities were applied: threefold sensory threshold (INT 1), motor plus sensory threshold (INT 2), individual level of tolerance (INT 3).

STATISTICS

Multivariate analyses of variance (independent variable: stimulation intensity).

RESULTS

Three negative and two positive midlatency components were identified after median nerve stimulation. At INT 1 the early waves N20, P25 and N35 were identified in all of the patients. In contrast, the component P45 was identifiable in 23% of the sample at the lowest intensity level and N55, respectively, in 32%. At INT 2 the spinal and the midlatency cortical amplitudes (except amplitude N35P45) were significantly increased (p < 0.014). At INT 3 the amplitudes of the primary cortical complex did not increase further, but the components > 35 ms became identifiable in the whole sample except in one subject. In contrast, there was no change in the MnSSER latencies. The intensity was comfortable for all subjects.

CONCLUSION

For monitoring the midlatency MnSSER components > 35 ms the authors suggest a stimulation intensity close to individual tolerance level for optimal cortical responses.

Vocal development of 9-month-old babies with cleft palate

This study compared the prelinguistic vocal development of 9-month-old babies with unrepaired cleft palate (n = 30) and age-matched peers (n = 15). Samples of the babies' spontaneous vocalizations were obtained while they interacted with their primary caregiver during play. The groups were compared on a number of variables including (a) canonical babbling ratios, (b) percentage of babies who reached the canonical babbling stage by 9 months, (c) syllable and segmental aspects of babbling, and (d) vocal frequency. Results indicated that the babies with cleft palate had smaller canonical babbling ratios than their age-matched peers, with just 57% of the babies with cleft palate reaching the canonical babbling stage by 9 months compared to 93% of the noncleft babies. Although syllable types and length were similar for the two groups, differences were noted for consonant characteristics. The babies with cleft palate had smaller consonant inventories, with fewer stops, glides, and velars noted. Glottals occurred more frequently in the vocalizations of the babies with cleft palate. Finally, no statistically significant difference was noted in the number of vocalizations produced by the two groups. Some possible explanations for why babies with cleft palate are delayed in babbling are explored.

Modulation of chemokine production in lung microvascular endothelial cells by dopamine is mediated via an oxidative mechanism

Serum concentrations of catecholamines are high in patients with sepsis or acute respiratory distress syndrome (ARDS). Because chemokines mediate the recruitment of neutrophils into inflammatory sites, we addressed the question of whether dopamine (DA) is able to influence chemokine production in endothelial cells under basal and proinflammatory conditions. To this end, lung microvascular endothelial cells (LMVEC) were stimulated or not for 24 h with the bacterial toxins lipopolysaccharide (LPS) (1 microg/ml) or lipoteichonic acid (LTA) (10 microg/ml) in the presence or absence of various concentrations of DA (1-100 microg/ml). Whereas under basal and stimulatory conditions, the addition of DA to endothelial cells dose-dependently increased IL-8 production, the production of ENA-78 and Gro-alpha was significantly inhibited (P < 0.01). This effect could still be demonstrated when the cells were stimulated for up to 3 h with LPS before DA administration. Similar findings were detected for the mRNA expression of these chemokines. The influence of DA on chemokine production was not receptor mediated and could be prevented by antioxidants or radical scavengers. Moreover, addition of H(2)O(2) to endothelial cells gave results similar to those observed with DA stimulation, suggesting a pivotal role for reactive oxygen species in DA-mediated modulation of chemokine production in endothelial cells. Our data thus demonstrate that DA administration results in the induction of oxidative stress, with profound effects on endothelial chemokine production.