Development and demonstration of a new SANEX Partitioning Process for selective actinide(III)/lanthanide(III) separation using a mixture of CyMe4BTBP and TODGA

Within the framework of the European collaborative project ACSEPT, a new SANEX partitioning process was developed at Forschungszentrum Jülich for the separation of the trivalent minor actinides americium, curium and californium from lanthanide fission products in spent nuclear fuels. The development is based on batch solvent extraction studies, single-centrifugal contactor tests and on flow-sheet design by computer code calculations. The used solvent is composed of 6,6´-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydrobenzo-[1,2-4]trizazin-3-yl)-[2,2´]-bipyridine (CyMe4BTBP) and N,N,N´,N´-tetraoctyldiglycolamide (TODGA) dissolved in n-octanol. A spiked continuous counter-current test was carried out in miniature centrifugal contactors with the aid of a 20-stage flow-sheet consisting of 12 extraction, 4 scrubbing and 4 stripping stages. A product fraction containing more than 99.9% of the trivalent actinides Am(III), Cm(III) and Cf(III) was obtained. High product/feed decontamination factors >1000 were achieved for these actinides. The trivalent lanthanides were directed to the raffinate of the process with the actinide (III) product stream being contaminated with less than 0.5 mass-% in the initial lanthanides.

School-based intervention to reduce anxiety in children: study protocol for a randomized controlled trial (PACES)

Background

Emotional problems such as anxiety and low mood in children are common, impair everyday functioning and increase the risk of severe mental health disorders in adulthood. Relatively few children with emotional health problems are identified and referred for treatment indicating the need to investigate preventive approaches.

Methods/Design

The study is designed to be a pragmatic cluster randomized controlled trial evaluating the effectiveness of an efficacious school-based cognitive behavior therapy (CBT) prevention program (FRIENDS) on symptoms of anxiety and low mood in children 9 to 10 years of age. The unit of allocation is schools which are assigned to one of three conditions: school-led FRIENDS, health-led FRIENDS or treatment as usual. Assessments will be undertaken at baseline, 6 months and 12 months. The primary outcome measure is change on the Revised Child Anxiety and Depression Scale. Secondary outcome measures assess changes in self-esteem, worries, bullying and life satisfaction. An economic evaluation will be undertaken.

Discussion

As of September 2011, 41 schools have been recruited and randomized. Final 12-month assessments are scheduled to be completed by May 2013.

Trial Registration

ISRCTN23563048

Analysing trajectories of professional learning in changing workplaces

In order to study the mutual shaping of action and institutional setting there is a need for a method of analysing data which provides a window on the contingent and sequential emergence of new ways of thinking and speaking in specific institutional contexts. This paper addresses this challenge through a consideration of the developments that were made during a 4-year study of professional learning in settings which were subject to new legal requirements for multiagency working in children’s services in England.

Turning principles into practice in Alzheimer's disease

The prevalence of dementia is reaching epidemic proportions globally, but there remain a number of issues that prevent people with dementia, their families and caregivers, from taking control of their condition. In 2008, Alzheimer's Disease International (ADI) launched a Global Alzheimer's Disease Charter, which comprises six principles that underscore the urgency for a more ambitious approach to diagnosis, treatment and care. This review highlights some of the most important aspects and challenges of dementia diagnosis and treatment. These issues are reviewed in light of the six principles of the recent ADI Charter: promoting dementia awareness and understanding; respecting human rights; recognizing the key role of families and caregivers; providing access to health and social care; stressing the importance of optimal diagnosis and treatment; and preventing dementia through improvements in public health. The authors continue to hope that, one day, a cure for Alzheimer's disease will be found. Meanwhile, healthcare professionals need to unite in rising to the challenge of managing all cases of dementia, using the tools available to us now to work toward improved patient care.

A Study of Information Seeking by Cancer Patients and their Carers

AIMS

To examine cancer patients' and carers' use of, and attitudes to, the Internet as an information source compared with other media.

MATERIALS AND METHODS

The study was carried out in two phases: in phase I, interviews were used to construct a suitable instrument. In phase II, interviews were completed with 800 recently diagnosed patients and 200 carers.

RESULTS

Relatively few patients (4.8%), but a high proportion of carers (48%), accessed the Internet directly for cancer information. However, around half of the patients used Internet information provided by someone else, generally a family member. The use of Internet information was uniformly low among ethnic minorities. Those who accessed Internet information reported high levels of satisfaction and generally rated it higher than booklets or leaflets. When asked who they would like to provide Internet information, overwhelmingly patients wanted the hospital doctor to do so. When this was done, there was very high compliance. Carers were much more proactive information seekers than patients.

CONCLUSIONS

The Internet is an effective means of information provision in those who use it. Facilitated Internet access and directed use by health professionals would be effective ways of broadening access to this medium.

Cardiorespiratory events recorded on home monitors: the effect of prematurity on later serious events

OBJECTIVE

To describe severe alarms on home-documented monitoring in infants born prematurely.

METHODS

In infants born at a post-menstrual age (PMA) less than 35 weeks, a polysomnography was performed before discharge. A heart rate less than 50 beats per minute (bpm) for more than 3 seconds or an apnea lasting for more than 15 seconds with a heart rate less than 60 bpm were defined as abnormal. These babies were given cardiorespiratory home monitoring with memory. Serious alarms on the home monitor were defined as heart rate less than 50 bpm for more than 3 seconds.

RESULTS

Of 1058 infants, 96 infants needed cardiorespiratory home monitoring. Sixty-one infants showed alarms at home. The mean post-conceptional age (PCA) when alarms stopped was 46 weeks. Seventeen patients had serious alarms above the PCA of 50 weeks. There was a significant negative correlation (r = -0.46 and p = 0.0002 by Spearman's rank correlation) between the PMA at birth and the PCA at which the last alarm was noted

CONCLUSION

Prematurely born infants with an abnormal polysomnography at discharge are at high risk for developing acute events at home. A younger PMA at birth correlates with a higher risk of alarms at a later PCA.

Nutrient Composition of Larval Nectar Secretions from Three Species of Myrmecophilous Butterflies

A comparative chemical analysis of the larval nectar secretions and hemolymph from three unspecifically and facultatively ant-attended lycaenid species (Polyommatus coridon, P. icarus, and Zizeeria knysna) was performed by using high-performance liquid chromatography techniques. Sucrose was the main sugar component in all three species. In half of the samples of P. coridon, it was accompanied by glucose, whereas other sugars occurred only rarely. In P. icarus and Z. knysna, melezitose was the second-most important component, followed by fructose and glucose. Total sugar contents were 43.6 +/- 14.8 g/l (mean +/- SD) for P. coridon, 74.2 g/l for P. icarus, and 68.3 +/- 22.6 g/l for Z. knysna. Up to 14 different identified amino acids were found in P. coridon nectar, with a total content of 9.7 +/- 3.4 g/l. Leucine was always the major component (contributing 50% of overall amino acid content). Other important amino acids were tyrosine, proline, arginine, and phenylalanine. P. icarus nectar contained up to six amino acids with a total content of 1.2 g/l, dominated by tyrosine and phenylalanine. Z. knysna nectar contained alanine and proline, with only 0.3 +/- 0.17 g/l total content. In the hemolymph of all species, up to 16 different amino acids occurred relatively regularly, with histidine dominating, followed by serine and proline. The amino acid pattern in hemolymph was considerably different from that of the nectar secretions. Larval diet weakly influenced P. coridon nectar sugars, and with a semisynthetic diet, a more homogeneous amino acid pattern was detected. Comparison with reports from other lycaenid species shows that secretions rich in amino acids are related to intimate, often obligate ant associations, whereas facultative, unspecific myrmecophiles rely on carbohydrates.

Characteristics of respiratory syncytial virus-related apnoea in three infants

Apnoea is a common sign in respiratory syncytial virus (RSV) infections in young infants and can be the first presentation of an acquired RSV infection. We describe polysomnographic recordings of three infants revealing prolonged RSV-related apnoea before RSV infection was diagnosed. The apnoeas were of central origin. The caregivers had not noted any apparent life-threatening events (ALTE) prior to the polysomnography. Cardiorespiratory monitoring after the acute infection did not reveal any further apnoeas.

CONCLUSION

Central, prolonged apnoea can be the first sign of an acquired RSV infection in young infants in the absence of other respiratory symptoms and without any previous observation of apnoea by the caregivers.

The influence of school culture on smoking among pupils

School factors and not solely pupil composition probably cause variation in smoking prevalence amongst schools, but there are no theoretical models to explain why. In this paper we propose a hypothesis to explain schools' influence on pupils' smoking and test this using an existing cross-sectional survey of 23,282 pupils from 166 secondary schools in the West Midlands, UK. We hypothesise that school-level educational achievement scores would not be associated with smoking prevalence, but schools providing value-added education given the social background of pupils (authoritative schools) would provide effective support and control, have a relatively strong influence on pupils' lives and be associated with lower than average smoking prevalence. Schools providing value-denuded education (laissez-faire schools) would have a relatively weak influence on pupils' lives and be associated with higher than average smoking prevalence. The school achievement measures were the proportion of pupils achieving 5A-C General Certificates of Secondary Education (5A-Cs) grades and the proportion of half days lost to truancy. Value-added/denuded terms were created by regressing 5A-Cs and truancy on five markers of the social profile of pupils at the school. Authoritative schools achieved better than expected rates on both measures. Laissez-faire schools achieved worse than expected rates on both measures. All other schools were classed as indeterminate. Multilevel logistic regression was used to relate the risk of regular smoking to school culture in both achievement and authoritative/laissez-faire terms, both with and without adjustment for pupil-level risk factors for smoking. As predicted, schools' achievement measures were unrelated to pupils' smoking. The odds ratios (95% confidence intervals) for smoking in authoritative and laissez-faire schools relative to indeterminate schools were 0.80 (0.70-0.91) and 1.16 (1.07-1.27), respectively. Adjustment for pupil-level smoking risk factors had little effect. School culture is an independent risk factor for adolescent smoking. Schools providing effective support and control might protect pupils from smoking.

Iron supplementation in preterm infants: a study comparing the effect and tolerance of a Fe2+ and a nonionic FeIII compound

The more widely used divalent forms of iron (Fe2+) supplementation often lead to gastrointestinal symptoms in preterm infants although little is known about the use of nonionic trivalent iron preparations (FeIII) in these patients. It is especially under this nonionic form that dietary iron is available. For this reason, a randomized controlled study was undertaken to compare the efficacy and the extent of possible side effects in two groups of preterm infants. In one group, the elemental iron was given in the Fe2+ form, while the other group received a nonionic trivalent iron (FeIII) complexed with polysaccharides of low molecular weight. Both groups received 7.5 mg elemental iron daily. Measured parameters in the two study groups did not differ significantly throughout the study period of 14 weeks. Both forms of iron supplementation were well tolerated. However, vomiting, diarrhea, or constipation occurred slightly more often in the group receiving iron supplementation in the Fe2+ form without reaching statistical difference. The authors found a nonionic trivalent polysaccharide-iron complex given as iron supplementation as effective as the generally more favored ferrous sulphate. Since iron therapy is mandatory in the preterm infant, the use of trivalent iron complexes can be considered as a good alternative.

Three-dimensional imaging of acetabular dysplasia: diagnostic value and impact on surgical type classification

OBJECTIVE

To investigate the diagnostic value and the impact on surgical type classification of three-dimensional (3D) images for pre-surgical evaluation of dysplastic hips.

MATERIALS AND METHODS

Three children with a different surgical type of hip dysplasia were investigated with helical computed tomography. For each patient, two-dimensional (2D) images, 3D, and a stereolithographic model of the dysplastic hip were generated. In two separate sessions, 40 medical observers independently analyzed the 2D images (session 1), the 2D and 3D images (session 2), and tried to identify the corresponding stereolithographic hip model. The influence of both image presentation (2D versus 3D images) and observer (degree of experience, radiologist versus orthopedic surgeon) were statistically analyzed. The SL model choice reflected the impact on surgical type classification.

RESULTS

Image presentation was a significant factor whereas the individual observer was not. Three-dimensional images scored significantly better than 2D images (P=0.0003). Three-dimensional imaging increased the correct surgical type classification by 35%.

CONCLUSION

Three-dimensional images significantly improve the pre-surgical diagnostic assessment and surgical type classification of dysplastic hips.

Lymphoblastoid interferon alfa with or without steroid pretreatment in children with chronic hepatitis B: a multicenter controlled trial

The comparative efficacy of prednisolone followed by interferon alfa (IFN-alpha) versus IFN-alpha alone in enhancing the rate of antibody to hepatitis B e antigen (anti-HBe) seroconversion has not been evaluated in a large cohort of white children. To determine this, a multicenter-controlled trial was conducted in 95 hepatitis B virus (HBV)-DNA/hepatitis B e antigen (HBeAg)-positive children (median age, 9 years [range, 2-16 years]; 56 boys; 84 [89 percent] white), all having inflammatory changes on liver biopsy. Patients were randomized to receive either prednisolone followed by IFN-alpha (n = 34); placebo followed by IFN-alpha (n = 30); or no treatment (n = 31). The prednisolone/placebo was given on a double-blind basis. Lymphoblastoid IFN-alpha was given at 5 MU/m(2) three times a week for 12 weeks. Baseline clinical, biochemical, and histological features were similar for the three groups. The majority (85 percent) had a baseline aspartate aminotransferase (AST) level < or = 100 IU/L. On follow-up between 12 and 18 months (median, 15 months) after treatment, the loss of HBeAg with anti-HBe seroconversion was more common in patients pretreated with steroids (12 of 34 [35 percent]) or placebo [12 of 30 (40 percent)] as against controls (4 of 31 [13 percent], P< .05). Factors predictive of anti-HBe seroconversion were baseline HBV-DNA concentration of < or = 1,000 pg/mL and a greater degree of portal tract inflammation on pretrial biopsy. Our results show that in white children treatment with IFN-alpha, at the dose and duration used in this study, improves the rate of anti-HBe seroconversion. Steroid priming does not potentiate the effect of IFN-alpha.

Birth weight and early lung compliance as predictors of short-term outcome in premature infants with respiratory distress syndrome

In addition to birth weight (BW), respiratory mechanics during the first week of life have been reported to predict outcome in ventilated newborn infants with respiratory distress syndrome (RDS). Most measuring techniques are invasive, requiring the placement of an oesophageal tube or balloon. In the present study the compliance (Crs) and resistance (Rrs) of the total respiratory system were measured without an oesophageal tube , using a commercially available system (PEDS; MAS Inc., Hatfield, Pa.) . The Crs and Rrs were determined once, within 24 hours of birth, in 28 preterm infants requiring mechanical ventilation for RDS. Variables such as gestational age (GA) and BW were also evaluated for their predictive role in outcome. Poor outcome was defined as death from respiratory failure or the development of bronchopulmonary dysplasia (BPD) at 28 days. All non-survivors died of refractory respiratory failure, at a median of age of 6 days. The median Crs of the 21 survivors was 0.5 ml/cm H2O and of the non-survivors 0.21 ml/cm H2O (P = 0.01). Crs below 0.45 ml/cm H2O predicted 15 of the 16 infants who either developed BPD or died (positive predictive value 100%; negative predictive value 92%; sensitivity 94%; specificity 100%). Nine survivors, who subsequently developed B PD, had a median Crs of 0.38 ml/cm H2O. Their Crs was significantly lowe r than that of the infants without evidence of BPD (Crs = 0.61 ml/cm H2O ) (P = 0.01). All of the 12 babies without BPD who survived had median C rs values above 0.45 ml/cm H2O. The median Rrs of the 9 infants with BPD (96 cm H2O/l/s) was also significantly higher than the Rrs value of the non-BPD group (59 cm H2O/l/s) (P = 0.05). When stepwise multiple logistic regression was applied to predict outcome, the only variable that could be entered at a 0.05 level of significance was BW. Uncorrected compliance entered the second step, but did not reach statistical significance. We conclude that in premature infants with RDS, BW is a strong predictor of outcome. Although determination of the Crs within the first 24 hours after birth did not add significance to this predictive model, it was nevertheless a useful parameter to determine respiratory morbidity and mortality.

Photodynamic action of ultraviolet A: induction of cellular hydroperoxides

Long-wavelength ultraviolet radiation (UVA) can cause cancer. A carcinogenic mechanism involved may be the induction of harmful reactive oxygen species resulting from photodynamic effects. UVA is generally assumed to induce photodynamic effects, but evidence from experiments with viable biological materials has been indirect until present. Here we measured the induction of (lipid) hydroperoxides as direct indicators of photodynamic reactions. Cultured human fibroblasts were irradiated with 10J UVA/cm2. The induced hydroperoxides were measured by an enzymatic method using glutathione peroxidase and glutathione reductase (GR). Additionally, reduced glutathione (GSH) was determined as parameter for the constitutive antioxidant defense. UVA was found to increase lipid hydroperoxides in fibroblasts by 116% (p < 0.001), when compared to nonirradiated controls. Conversely GSH was decreased in the irradiated cells by 51% (p < 0.001). Because of the induced hydroperoxides, it is concluded that the UVA effects were mediated by a photodynamic mechanism. The photodynamic mechanism resulted in the formation of reactive oxygen species and the consumption of constitutive antioxidants. This suggests a role for antioxidants during the photodynamic mechanism. Photodynamic mechanisms may play a crucial role in carcinogenic events, especially after UVA.

Chronic ethanol alters CNS cholinergic and cerebellar development in chick embryos

Chick embryos were given daily injections of ethanol (approximately 30 mg/day) either chronically from embryonic days 4 to 15 (E4-E15) or E18, or acutely from E15 to E18. Untreated and saline-injected embryos served as controls. Although morphological indicators of developmental age were not different among groups, chronic ethanol reduced weights of several brain regions. Similar to rodent models of prenatal ethanol exposure, chronic ethanol treatment reduced cerebellar Purkinje cell numbers compared to controls. Chronic but not acute ethanol exposure resulted in a significant reduction in choline acetyltransferase activity in the optic tectum (OT) and forebrain (FB) compared with controls. This study demonstrates that the chick embryo is a viable model to investigate the effects of ethanol exposure on CNS development. Unlike the mammalian fetus, the avian embryo is isolated from maternal interactions and may prove more useful in investigating the mechanisms by which ethanol directly influences brain development.

Cerebral hyperperfusion following episodes of bradycardia in the preterm infant

The alterations in cerebral hemodynamics during and following 39 episodes with bradycardia of different severity have been studied by analysis of Doppler flow velocity waveforms amongst 16 stable preterm infants (range of conceptional age at the time of study 33-39 weeks; weight 1730-2820 g). Each episode with bradycardia has been classified as mild on seven occasions (heart rate between 100-120 beats/min), moderate on 15 occasions (80-100), or severe on 17 occasions (heart rate below 80) Depending on the severity of the bradycardia, the time-averaged mean flow velocity (V) could decrease by 80% below the preexistent baseline value and the end-diastolic velocity (D) dropped towards the zero line, whereas peak systolic velocities did not change The magnitude of the percentage decrease of V correlated positively with the severity of bradycardia, indicating a progressive decline of cerebral blood flow (CBF). Following bradycardia, V could increase up to 75% above the preexistent baseline value. Simultaneously, an increase of mean arterial blood pressure and D could be documented. Peak systolic velocities remained unaltered. The magnitude of the percentage increase of V following bradycardia depended both on the severity of bradycardia as well as on the drop in transcutaneous oxygen during the preceding bradycardia. Interpretation of these findings suggested that the transient cerebral hyperperfusion following bradycardia compensates for the hypoxic-ischemic episode, sustained during the preceding epoch of apnea and bradycardia.

The "deterministic simple epidemic" unmasked

We derive a simple but surprising connection between the "deterministic epidemic with recovery" and the spatial birth-and-death process, and discuss its implications for the use of nonlinear differential equation models for the spatial spread of epidemics. This paper consists of a manuscript dating back to 1977, which has been widely referred to in the literature but not previously published, and its more recent extension to include recovery/death in the processes considered, with some additional comments. To aid reference, we retain the original title.

The influence of blood transfusion on brain blood flow autoregulation among stable preterm infants

Prior to and 24 h following blood transfusion serial determinations of both cerebral artery flow velocity waveforms and mean arterial blood pressure have been used to reconstruct the autoregulatory curve and its upper blood pressure limit among five stable preterm infants. Prior to transfusion the autoregulatory range of cerebral blood flow (CBF) was narrow due to a relatively low-set upper blood pressure limit. At 24 h after transfusion each individual has been re-examined. Following correction of anemia both a significant reduction of CBF velocities as well as a concomitant rise of the Pulsatility Index (PI) occurred over the entire range of blood pressures indicating a reduction of CBF after transfusion. In addition a right-sided shift of the upper limit towards higher mean blood pressures occurred after transfusion and resulted in an extension of the autoregulatory plateau of CBF. These favourable effects of blood transfusion ameliorating autoregulation of brain blood flow particularly at higher blood pressures might well bear important therapeutic perspectives in our effort to prevent intracranial haemorrhage among sick preterm infants.

Prediction of neurodevelopmental outcome in the preterm infant: short latency cortical somatosensory evoked potentials compared with cranial ultrasound

One hundred and twenty six preterm infants, with a gestational age of 34 weeks or less, were studied to compare the predictive value of somatosensory evoked potentials (SEPs) with that of cranial ultrasound. A normal N1 latency was no guarantee of a normal outcome, nor did a persistently delayed N1 latency always correlate with a poor outcome. As a predictor of cerebral palsy, SEPs had a sensitivity of 44% and a specificity of 92%. The presence of a large haemorrhage (grade IIb/III) or cystic leukomalacia on cranial ultrasound predicted cerebral palsy with a sensitivity of 73.6% and a specificity of 83.1%. These results demonstrate that the role of SEPs recorded after median nerve stimulation is limited in preterm infants.

Effect of prenatal betamethasone/thyrotropin releasing hormone treatment on somatosensory evoked potentials in preterm newborns

The maternal administration of betamethasone and thyrotropin releasing hormone (TRH) to accelerate the maturation of the fetus is an increasingly adopted strategy to prevent neonatal morbidity in preterm infants. The effect of this prenatal treatment on the neural maturation of the infant was assessed by measuring somatosensory evoked potentials (SEP) in preterm infants (gestational age 29-36 wk) on the 1st postnatal day, at the age of 1 wk, and before discharge. The N1 latency values of the SEP obtained in 14 infants who were exposed prenatally to betamethasone/TRH were compared with the N1 latencies measured in 12 control infants. On the 1st postnatal day, the N1 latencies in the betamethasone/TRH-treated infants were strikingly shorter (p less than 0.01) than in the controls. However, at the age of 1 wk and at discharge, the N1 latency values of both groups were similar. In conclusion, the present study provides the first solid evidence for the concept that the prenatal exposure to betamethasone/TRH accelerates the SEP-assessed neural maturation of the human fetus, that this prenatal acceleration is followed by a compensatory relative deceleration during the early neonatal period, and that the subsequent SEP-assessed neural maturation proceeds at a normal velocity.

Brain oxygen transport related to levels of fetal haemoglobin in stable preterm infants

The relative amount of regional cerebral oxygen transport was compared between different preterm infants by performing measurements of cerebral blood flow velocity, mean arterial blood pressure, whole blood viscosity and haemoglobin content for each individual. In addition the percentage of fetal haemoglobin was determined. On 25 occasions measurements of fetal haemoglobin and cerebral oxygen transport have been performed prior to and following a blood transfusion with adult red blood cells. Comparison of the data for cerebral oxygen transport suggests that the actual amount of cerebral oxygen transport is lowest at fetal haemoglobin levels below 30% and will increase progressively as soon as the percentage of fetal haemoglobin rises about 30%. Thus, at increasing fetal haemoglobin levels, cerebral haemodynamic mechanisms in the human neonate cause elevations of regional cerebral blood flow and oxygen transport. The found increase of cerebral blood flow and oxygen transport at high fetal haemoglobin levels will minimize the impeded dissociation and delivery of oxygen to brain tissues.

The diaphragm of the newborn infant: anatomical and ultrasonographic studies

In the newborn infant, the diaphragm seems badly adapted to perform the burden of respiratory work. Indeed, due to the large angle of insertion on the rib cage and the small area of apposition, the flat diaphragm of the newborn infant seems better designed to suck in the rib cage rather than air. To better understand this paradox, and get insight in the structure-function relationship, the anatomical connections between the diaphragm and the rib cage were studied in 16 infants of various postmenstrual and postnatal ages. It was concluded (1) that the diaphragm inserts on the rib cage border only in the anterior costo-diaphragmatic triangle. From antero-laterally to posteriorly it inserts at increasingly greater distance from the rib cage border; (2) that the dorsal diaphragm ends its free course at the 11th rib and continues caudally as a spur ending between the 12th rib and the crista iliaca. From echographic studies of the right diaphragm with simultaneous measurement of the caudad displacement of the diaphragm and abdominal circumference change, the dynamics of the diaphragmatic movements could be better understood. It was concluded that, in contrast with the adult diaphragm, acting as a piston within the rib cage, the diaphragm of the newborn infant acts as a below moving mainly in the posterior part.(ABSTRACT TRUNCATED AT 250 WORDS)

Prognostic value of early somatosensory evoked potentials for adverse outcome in full-term infants with birth asphyxia

SEPs were examined during the first weeks of life in 34 infants with mild to severe birth asphyxia, in an attempt to provide a more accurate prediction of neurodevelopmental outcome. Normal, delayed and absent responses were compared with the infant's acute clinical condition, imaging findings using different imaging techniques and neurodevelopmental outcome. All infants with normal SEPs were normal at follow-up. All but two of the infants with a delayed or absent response died or suffered from severe neurological sequelae. A delayed or absent N1 latency carried a risk for death or severe handicap of 71 and 100%, respectively, compared with 25 and 89% for moderate or severe encephalopathy on neurological assessment, and 29 and 85% for moderate or severe changes seen using different imaging techniques. SEPs may provide useful additional information when assessing the infant with birth asphyxia.

T lymphocyte activation is associated with viral replication in chronic hepatitis B virus infection of childhood

Activated circulating T lymphocytes expressing HLA-DR (mean +/- s.d. 11.0 +/- 5.2%) or interleukin-2 receptor (IL-2R) (2.1 +/- 1.7%) were significantly increased in 63 children with chronic hepatitis B virus (HBV) infection when compared with 33 age-matched healthy controls (3.0 +/- 1.3%, P less than 0.01, and 0.1 +/- 0.4%, P less than 0.01). HBeAg-positive patients had higher percentage of DR (11.9 +/- 5.1%) or IL-2R (2.4 +/- 1.7%) positive T lymphocytes than anti-HBe-positive children (7.4 +/- 3.6% and 1.1 +/- 1.5%, P less than 0.01 and P = 0.02 respectively). Similarly, HBV DNA-positive patients had higher percentage of DR (10.5 +/- 3.3) or IL-2R (3.2 +/- 1.7%) positive T cells than HBV DNA-negative children (6.6 +/- 2.8% and 1.2 +/- 1.5%, P less than 0.01 for both). There was a positive correlation between percentage of DR positive T lymphocytes and levels of HBV DNA. Sixty-two per cent of the DR-positive T lymphocytes were cytotoxic/suppressor and 35% helper/inducer. The relationship between viral replication and T lymphocyte activation is discussed.

Influence of virginiamycin on growth and efficiency of large white turkeys

Efficacy of virginiamycin (22 mg/kg) in combination with no drug, amprolium, carbarsone, halofuginone, or monensin, was studied. Male and female turkeys were raised to market age in five experiments conducted from 1983 to 1987. Body weights and feed:gain responses to virginiamycin for males and females were positive and significant (P less than .05). Virginiamycin resulted in mean 5.2 and 6.3% body weight responses and 3.3 and 2.2% feed:gain responses for males at 19 or 20 wk of age and for females at 16 or 17 wk of age, respectively. Mortality rates were low in all studies, and were not influenced by virginiamycin. In a processing study, virginiamycin in combination with halofuginone did not affect shrinkage, yield, or market grade. Feed was utilized by males and females 3.9 and 3.0%, respectively, more efficiently than expected with dietary virginiamycin, compared with results predicted by a simulation modeling technique. Profitability was considerably greater with dietary virginiamycin using actual data than with simulated feed consumption data.

Increased production of tumour necrosis factor alpha in chronic hepatitis B virus infection

Plasma tumour necrosis factor alpha (TNF) and in-vitro TNF production by peripheral blood mononuclear cells (PBMC) were studied in 22 HBsAg seropositive patients and compared with 23 normal and 10 disease controls. Plasma TNF and unstimulated TNF production correlated (Rs = 0.55, p = 0.012) and were significantly elevated in HBsAg and HBeAg seropositive patients (p less than 0.001, p = 0.006) compared with normal controls. TNF production was also elevated in these patients when PBMC were stimulated with interferon-gamma (p less than 0.05) or LPS (p = 0.035). Plasma TNF and TNF production in HBsAg anti-HBe seropositive subjects were not elevated. TNF production in unstimulated cells correlated with serum HBV DNA level (R = 0.53, p = 0.02) but not with serum aspartate transaminase (AST) or histological activity. It is concluded that PBMC are activated to produce TNF both spontaneously and in response to second stimuli in chronic hepatitis B virus infection and that this activity is related to the presence of viral replication.

Upper limits of brain blood flow autoregulation in stable infants of various conceptional age

In healthy adults cerebral blood flow is autoregulated and kept constant over a wide range of mean arterial blood pressures (MAP) between 60 and 150 mmHg. In 27 stable infants with different conceptional ages ranging from 33 to 50 weeks, Doppler measurements of mean flow velocity at the anterior cerebral artery have been recorded simultaneously with mean arterial blood pressures (MAP) during a period of 6 h. The range of autoregulation and its upper limit could thus be determined. The upper limit was found to increase with advancing age. In the infants with conceptional ages between 33 and 35 weeks, the upper limit of autoregulation varied between 45 and 60 mmHg, while the upper limit shifted to a MAP of 100 mmHg at 47 weeks conceptional age. A significant positive linear relationship existed between the upper limit of autoregulation and conceptional age.