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Thermodynamics, microscopic structure and (single molecule and collective) dynamics in Xe-N2 supercritical mixtures were studied using Molecular Dynamics simulations at a temperature of T = 323 K. The results agree well with previous experimental work on PVT-data and depolarized Rayleigh light scattering (DRLS). By using the corresponding DRLS time-correlation functions (TCFs), the contribution of orientational, interaction-induced and cross terms in the total DRLS TCF were evaluated. At all densities studied, the orientational part was found to be the most dominant. The Molecular Dynamics interaction potential model was compared with the most recent ab initio interaction potential energy surface (PES). Furthermore, quantum mechanical scattering calculations on the ab initio PES were used to provide integral and differential cross sections.

In this paper, the ordering in concentrated charge stabilized colloidal dispersions is considered. Despite the impressive Bragg reflections obtained for shear ordered dispersions by light (LS), small-angle neutron (SANS), and small-angle X-ray scattering (SAXS), a number of open questions remain. Sheared dispersions are usually ordered in layers. For such systems, two questions arise: (1) What is the structure in a layer? (2) What is the stacking structure perpendicular to the layers? The second question requires a method to determine the structure perpendicular to the layers. Although originally interested only in structural aspects, we were forced to consider different methods. Two methods are treated both applicable to neutron and X-ray scattering from concentrated dispersions. One has been used by physicists and chemists for many years to determine the structure of crystals by sample rotation. In colloid science, we have used it previously in neutron and X-ray scattering. A second method is treated here which can be applied in small-angle scattering from a Couette cell. It gives the scattering intensity in a certain direction without sample rotation. Although very useful with the Couette cell, it cannot be found in any of the well-known references on colloid science. A theoretical explanation and experimental examples obtained by synchrotron X-ray scattering from a Couette cell are given in the paper.

In this contribution small-angle scattering from layered systems is considered. When a colloidal dispersion is stirred it usually decomposes into layers. There are two important questions concerning these layers: What is the structure in a layer? What is the stacking structure between such layers? For concentrated colloidal dispersions both these questions can be investigated by small-angle scattering experiments. It will become apparent that the answer is also important for technical applications. Both a theoretical description as well as an experimental verification are given in the paper.

The present paper is concerned with the structure of dispersions made from charged polymer particles. First, the determination of important properties of single particles is discussed. It follows a typical phase diagram of charge stabilized dispersions. Their structure and possibilities to manipulate the structure are considered in the following sections. For the understanding of scattering experiments, as light scattering (LS), small angle neutron (SANS) and small angle synchrotron x-ray scattering (SAXS) the reciprocal lattice is of fundamental importance. A separate chapter, therefore, is dedicated to it. The application of shear has been found to be a particularly successful method for manipulating the structure of dispersions. It is possible to generate one-dimensional (1D) strings as well as plane (2D) layers which become (3D) crystals with time. The phenomena and structures generated by shear are in part surprising and at present not fully understood.

We report our experience of pacemaker treatment in a premature infant of 832 grams with congenital complete atrioventricular block due to maternal Sjogren's Syndrome. She was delivered by cesarean section at an estimated gestational age of 26 weeks because of fetal bradycardia, decreasing fetal movements and hydrops. Immediate postnatal transesophageal ventricular pacing was not successful, whereas transthoracic pacing with self-adhesive patch electrodes adapted to body size resulted in an effective increase of the infant's heart rate until operative application of temporary epimyocardial pacing wires ensured the external stimulation of the heart.

The influence of shear on the Bragg scattering of concentrated colloidal dispersions made from charged particles is considered in this paper. First, the reciprocal space of a layered sample at rest and under the influence of a disordering torque is considered. Next, the commonly used Couette cell and our disk shear cell are compared in view of the Ewald construction. An introduction of α- and β-rotation axes follows. The first experimental example is concerned with the neutron scattering from a layered colloidal sample at rest. As a second experimental example from the same sample the dependence of synchrotron X-ray scattering on the shear rate is considered. It turns out that the sample does not achieve a microcrystalline state as claimed previously but remains in an orientationally disordered layered state. Finally, the intensity distribution I(l) along the two types of Bragg rods as obtained with remarkable precision by synchrotron X-ray scattering is presented.

In this work the Couette cell is compared with a more recently constructed disk shear cell. There are distinct advantages of the disk over the Couette cell, in particular, when it comes to the determination of the intensity along certain Bragg rods.

Objectives We review the efficacy of oral sugar solutions for treating procedural pain in neonates and address the following questions: Do newborns need analgesic therapy for procedural pain during blood sampling? How do sugars influence pain-reactions of neonates? What is the efficacy of sugar solutions in clinical practice? Methods We searched for relevant articles in the PubMed database from 1990 to September 2000. Results Treatment of procedural pain in newborns is desirable because they are more sensitive to pain than adults, they show marked pain reactions during blood sampling and repeated acute pain in the newborn period results in longterm behavioural changes. Oral sugar solutions have been studied for treatment of procedural pain in neonates. Their initial effect is the result of orotactile stimulation by the intraoral fluid. The orogustatory stimulation by the sweet taste prolongs the effect for up to 10 minutes through endorphin release. In randomized-controlled trials oral sugar solutions (2 ml of 25% sucrose or 30% glucose) reduced pain reactions and crying and attenuated the heart rate increase after capillary and venous blood sampling in term and preterm neonates. They are more effective than traditional calming strategies, like cuddling by parents, use of a pacifier, or breast feeding. Yet, sugar solutions provide no adequate analgesia for more severe pain, e.g. during circumcision. Conclusions Sugar solutions effectively relieve procedural pain during blood sampling in neonates. Additional studies are needed to determine the minimal effective dose and the efficacy and side effects of repeated sugar doses in the same patient.

A study is reported on the final stage of sedimentation of colloidal particles using Brownian dynamics simulation. For mono- and bidisperse systems at two different densities confined between two walls there was pronounced layering and a wealth of different states of order which were strongly height dependent. Also, phase separation in the bidisperse models could occur. In each system the layers were investigated individually by defining planar observables and comparing them with a dynamic freezing criterion.

The structure and dynamics of colloidal particles confined between two parallel walls is studied using Brownian dynamics simulation. The particle-particle interaction is modelled as a screened Coulomb potential and the particle-wall interaction is assumed to follow a simple exponential law. Static and dynamic observables are defined and computed for layers parallel to the walls. The numerical values are comparable qualitatively to results from microscopy experiments. It is found that the influence of the wall leads to a higher ordering of the suspension near to it and to an anisotropic diffusion. The corresponding mean-square displacement is described well by the Cichocki–Felderhof model.

This paper is concerned with video microscopy, an analytical method of growing importance for the studies of colloid suspensions. Particular emphasis of this work will be laid on the derivation of simple recipes for the computation of static and dynamic pair correlation functions from the microscopic images. The strengths and also the weaknesses of the method will be discussed in detail. We will also present a selection of results gained by this method to demonstrate, that video microscopy is a valuable addition to the well established analytical methods like neutron and laser light scattering in colloid science.

Kossel rings of colloidal dispersions obtained with colloids at rest and under flowing conditions are described. When flowing only Kossel rings of planes with a component in the direction of the flow do not vanish. Compared with the dispersion at rest the number of Kossel rings of the dispersions under flow is reduced. Experimental examples are presented.

Through modern reproductive techniques Hellin's rule, approximating multiple births, is no longer applicable. Consequently perinatal centres have been facing an increasing number of multifoetal pregnancies during the last 15 years. The foetal outcome of 81 multifoetal pregnancies, delivered between January 1, 1980 and June 30, 1995 at the Klinik und Poliklinik fur Frauenheilkunde und Geburtshilfe im Klinikum Grosshadern, Munich, Germany, illustrates both the risk as well as the chance for healthy survival under the applied management protocol. Mean gestational ages at delivery were 221 days (31 + 4 weeks) for triplets, 213 days (30 + 3 weeks) for quadruplets and 200 days (28 + 4 weeks) for quintuplets, mean birth weight was 1400 g, 1100g and 1080 g respectively. 96.4% of the triplets survived (188/195), 70% (137/195) could be discharged home without medical problems. 98.1% (51/52) of the quadruplets and 80% (12/15) of the quintuplets survived, 67% (35/52) and 53% (8/15) respectively without health impairment. Respiratory distress syndrome, intracranial hemorrhage, retinopathy of prematurity, persistent Ductus arteriosus, necrotising enterocolitis and hydrocephalus are primary causes of neonatal morbidity. Serious neurological sequels such as developmental retardation and cerebral palsy were noted in 4 (6%) and 5 (8%) of the quadruplets and quintuplets. Health impairment and mortality show a clear association to gestational age under 30 weeks but do not differ significantly in frequency or distribution from single or twin neonates of equal gestational age and management. A threshold regarding prognosis seems to be the number of foetuses 4 versus 5 and the gestational age before or after 210 days (30 weeks). Before 32 weeks of gestation the indication for delivery was most often due to foetal problems. With progressing duration of pregnancy the risk for maternal complications rises and may warrant termination of pregnancy in the face of a usually uncomplicated postnatal course of foetuses born after 32 weeks of gestation at a perinatal centre. The presented data suggest that an individually adapted, liberal indication for delivery by caesarean section after 32 weeks is the safest management scheme for mother and foetuses.

Des suspensions aqueuses de particules de bromopolystyrene ont ete caracterisees par diffusion de lumiere, diffusion de rayons X aux petits angles et par des mesures de pression osmotique. Nous avons ainsi etudie leur structure et les interactions interparticulaires en fonction de la fraction volumique a salinite constante de l'ordre de la micromole/1. Lorsque la cristallisation est lente, nous observons des cristaux parfaits cubiques centres par diffusion de lumiere pour des fractions volumiques comprises entre 0,04 et 0,7 % et cubiques faces centrees par diffusion de rayons X aux petits angles pour des fractions volumiques plus elevees (2-12 %). Apres cisaillement, des defauts apparaissent dans les cristaux ; ils sont caracterises par la disparition de certaines raies de Bragg en diffusion de lumiere pour des echantillons de fraction volumique comprise entre 0,1 et 0,3 % et par la presence d'un pre-pic observe par diffusion de rayons X aux petits angles avant le premier pic de Bragg, pour des echantillons plus concentres (2-12 %). Les pressions osmotiques ont ete mesurees par difference de pression hydrostatique entre la solution et le reservoir separes par une membrane hemipermeable. Les donnees experimentales sont bien reproduites par la theorie Poisson Boltzmann Reseau (PBR) qui montre que les interactions sont purement repulsives. Aucune force attractive faible de longue portee n'a ete detectee experimentalement. En calculant le deplacement moyen d'une particule a l'interieur de sa cage a l'aide du modele PBR excentre, nous avons verifie que le critere de Lindemann etait satisfait pour tous les cristaux observes. Cette etude a permis de determiner l'equation d'etat d'un cristal colloidal electrostatique. Les resultats sont equivalents a une mesure de force ultraprecise puisque les forces d'interaction mesurees entre particules sont de l'ordre de 10 -12 N pour des distances centre a centre de l'ordre de 4000 A.

Das Management der Hyperbilirubinamie bei reifen gesunden Neugeborenen ohne Hamolyse ist noch immer eine Angelegenheit von Interesse wegen Haufigkeit und Nebenwirkungen der Phototherapie, wie die Trennung der Mutter von ihren Kindern. Neue Daten uber Bilirubin und das Outcome der Kinder in dieser Gruppe in bezug auf Kernikterus, intellektuelle, neurologische und Horstorungen rechtfertigen ein weniger aggressives Management und Toleranz hoherer Bilirubingrenzwerte. Die Arbeitsgemeinschaft Berliner Neonatologen schlos sich den neuen Richtlinien der ”American Academy of Pediatrics„ an, Phototherapie erfolgt ab einem Gesamtbilirubin von 340 μmol/l (20 mg/dl) im Alter von > 72 h und 310 μmol/l (18 mg/dl) im Alter von 48–72 h. Die Phototherapiehaufigkeit konnte so von 9,7 auf 2,5% und die Haufigkeit von Blutentnahmen von 27,0 auf 14,5% gesenkt werden.

Mortality, Mode of Delivery, Pneumothorax and Intracranial Haemorrhage in 859 Very Low Birth-Weight Infants Between 1984-1992: In a retrospective study we investigated the mortality and the most important complications of all very low birth-weight infants (VLBW; ≤ 1500 g and/or ≤ 32 weeks) born with vital signs between 1984 and 1992 at the Klinikum Grosshadern, Munich University Hospital. During this period 859 premature infants fulfilled the entrance criteria. The perinatal mortality rate was 174/859 infants (20%). During the study period the mortality rate dropped significantly from 25% (1984-1986) to 15% (1990-1992). Premature infants born after 26 gestational weeks showed the most significant decrease in mortality. Excluding non viable infants with extreme immaturity (< 24 weeks of gestation) or lethal malformations, the mean corrected mortality rate was 11 %, decreasing over the years from 16% (1984-1986) to 5% (1990-1992). Caesarean section was performed in 70% of all children (602/859), vaginal delivery in 28% (239/859), delivery by forceps in 1% (7/859), and the mode of delivery was not clearly registrated in 1% (11/859). The incidence of Caesarean section increased significantly from 55% (1984-86) to 79% (1990-92). Evaluating the mode of delivery in relation to mortality, a significant difference was found between the infants delivered vaginally (40%, 95/239) and those delivered by Caesarean section (11 %, 67/602). This improved survival after Caesarean section was statistically significant for the group with a birth weight of less than 1500 g. The rate of pneumothorax also declined significantly from 19% to 9%. The rate of intracranial haemorrhage (ICH) remained almost constant during these years, but the incidence of ICH grade 3 and 4 decreased from 15% (1984-1986) to 6% (1990-1992). Probably because of improved antenatal care and the progress in neonatal intensive care, the chance of survival for VLBW infants has substantially improved over the last decade. Estimations of the prognosis of VLBW infants based on data from the 1980 s are out of date.

In this paper we investigated the single particle dynamics in a colloidal crystal by means of video microscopy and digital imaging methods. To obtain the self term of the van Hove function Gs(x,τ) with a reasonable good statistical accuracy we analyzed up to two million particle displacements per time channel τ of Gs(x,τ), which corresponds to the analysis of 3000 video frames, each with approximately 1000 particles. It was found that the Gaussian approximation almost perfectly accounts for the experimental results, so that the time evolution of Gs(x,τ) can solely be described by the mean square displacement 〈x2(τ)〉. The measured mean square displacements were compared with the model of a Brownian particle bound in a harmonic potential [Physica A 157, 705 (1989)]. The experimental curves approach the plateau value 〈x2(τ→∞)〉 of the mean square displacement much slower than is predicted by the model. From the plateau value of the mean square displacement the Lindemann parameter was determined for various sa...

Depolarized Rayleigh and Raman scattering from fluids is composed of orientational (OR), collision induced (CI), and cross (X) contributions. In order to investigate the influence of the interaction induced terms (CI and X) on allowed spectra (OR), C2H6, a molecule with a small ratio of the anisotropic part γ to the isotropic part α of the polarizability is considered. Both Rayleigh and ν3 Raman correlation functions were determined by molecular dynamics (MD) computer simulation and compared with experiment. The investigations extend over a wide range of densities (0.67ρc–2.85ρc, where ρc is the critical density, ρc=0.206 g/cm3). The different contributions to the time correlation functions (TCFs) were simulated within the frame of a first‐order center–center dipole–induced‐dipole polarizability model. The potential model used was a standard two‐site Lennard‐Jones potential. Details concerning partial OR, CI, and X correlation functions and second moments for Rayleigh and Raman scattering are presented. A...

In the last three years an interdisciplinary ECMO (extracorporeal membrane oxygenation) team has been set up at the Free University of Berlin in the Steglitz clinic. With this form of management, newborns only a few hours or days old who present with pulmonary failure can temporarily be managed with extracorporeal oxygenation until normal lung function is restored. The set up of this ECMO team, starting with experimental training in animal models, to the bedside clinical use is discussed. The following presentation of the first four cases managed here with ECMO aims to clarify the problems which may be encountered as well as amplifying its use as a life-saving measure.

Before the entry criteria for extracorporeal membrane oxygenation (ECMO) are met, newborns may require aggressive mechanical ventilation which may result in lung injury. The question arises whether the presence of a pneumothorax in these infants plays a role in the prognosis. Of the 21 newborns transferred to our hospital for ECMO, 8 were treated with ECMO. 9 of the 21 newborns developed a pneumothorax with conventional ventilation and 6 of these 9 newborns subsequently required ECMO. Infants who developed a pneumothorax but did not meet ECMO criteria and remained in the oxygenation index (01) range between 25 and 40 for more than 2 days had a poorer prognosis. If adequate oxygenation cannot be attained with acceptable mechanical ventilation and a more aggressive ventilation results in a pneumothorax, ECMO should be considered even if the oxygenation index is below 40.

Experimental and computer simulation values of the zeroth and second moments of the depolarized Rayleigh and Raman spectra of N2 are reported. A wide range of density at a fixed temperature of 50°C was covered. The density dependence of the spectral moments is due primarily to interaction-induced effects which are successfully modelled here assuming a first-order dipole-induced-dipole mechanism. The agreement between experiment and simulation is good, with the exception of spectra at state points where it appears that the ‘distinct’ term (i.e., the contribution from orientationally correlated pairs of molecules) is significant.

Dynamic and static light scattering is applied to concentrated suspensions of a new species of charged colloidal suspensions with a low refractive index. The polymer colloids which were obtained by polymerizing perfluorobutylacrylate could be index matched in a water/glycerol mixture. At volume fractions Φ greater than 0.22 a glass transition can be observed, which is manifested by the nondecaying components of the intermediate scattering functions. The intermediate scattering functions for a supercooled liquid sample and the predictions of the mode‐coupling theory for the β relaxation are compared over a large Q range. By using an exponent parameter λ=0.76 a good agreement between theory and experiment can be obtained.

In this paper depolarized Rayleigh and Raman spectra from N2 in the density range ρr = 0·007 to 2·43 (ρr = ρ/ρc) are reported. The main goal of our comparison of the two types of spectra is to demonstrate that rotation-vibration spectra over this range of fluid densities can be influenced by a change of the molecular moment of inertia on vibrational excitation. The effect is different from vibrational relaxation, self and distinct rotation, interaction induced, and other contributions usually considered as broadening or narrowing mechanisms of condensed phase Rayleigh and Raman bands. Although the mechanism is well established for gas phase rotation-vibration IR, Raman and electronic spectra [14], to the best of our knowledge it has been neglected so far in the context of rotation-vibration spectra at high densities. For comparison of experiments with classical molecular dynamics simulations, classical spectra are required. It is shown that in order to obtain classical spectra from rotation-vibration spec...

Computer simulations of the Rayleigh and Raman spectral time‐correlation functions (TCFs) are reported for N2 at 323 K and densities ranging from 0.48 to 2.5 times the critical value. The results are compared with experiment. Particular attention is paid to the density dependence of the spectral intensity due to the correlated permanent polarizability and to the interaction‐induced contributions to the polarizability. The partial cancellations that occur between various two‐, three‐, and four‐body terms in the cross and collision induced (CI) parts of the spectral TCFs are evaluated. It is shown that these terms are significant in both the Raman and the Rayleigh spectra, but cancellation greatly reduces their net contribution at all densities studied. The weak but uncancelled TCFs that are associated with orientational correlations of the molecular polarizability anisotropies are shown to be a significant part of the high density Rayleigh TCFs. It is argued that the long‐range nature of this TCF means tha...

A new, fast, and reproducible method of preparing ordered colloidal suspensions at very low salt concentrations is reported. Preparation times are reduced by 2 orders of magnitude compared to those for the usual methods. Particle concentration and salt contents can be monitored and controlled by optical and conductivity measurements. Transient effects appearing during continuous deionization of the sample are reported, and qualitative explanations of these effects are suggested

Static and dynamic light scattering experiments with crystal- and fluid-like ordered colloidal suspensions are reported. The systems were composed of two electrostatically interacting particle species of similar size and effective particle charge but different refractive index. The refractive index of the abundant species was matched to the index of the dispersing medium. The incoherent scattering from the mismatched second species was used to investigate the self-diffusion in the ordered suspension. Leakage of coherent scattering due to a slight mismatch was used to monitor simultaneously the structure factor S(Q) of the suspensions. – The self-dynamic structure factor Fs(Q,t) at several ionic strength of the suspension is analyzed in terms of mean-square displacements 〈R(t)2〉 and velocity autocorrelation functions v(0) v(t). The long time self-diffusion coefficient is determined as a function of the effective hard sphere volume fraction Φ.

Mixtures of liquid-like ordered polymer colloid suspensions made from particles with diameters 50 and 99 nm are investigated by polarized light scattering. The experimental results are compared with two theoretical approaches: the substitutional model with rescaled mean spherical approximation (RMSA) and the two-particle model with hypernetted chain (HNC) approximation. Although the two-particle model with HNC approximation provides a slightly better representation of the data than the substitutional model with RMSA, neither of the two approaches is in satisfactory agreement with the experiments. An improved theory should take into account the intrinsic polydispersity of the polymer particle species. Further, a systematic theoretical investigation, in which both the substitutional and the two-particle model are each combined with any of the available statistical methods as RMSA, HNC, PY and a mixture of the HNC and the PY closures, would be very useful.

In this paper, scattering from Bragg rods is considered. For layered colloidal structures, the intensity along Bragg rods reflects the stacking order of the layers. It is described how the small angle neutron (SANS) scattering intensity can be used to characterize layered systems. Scattering examples are presented for colloidal layers at rest and under sheared (flowing) conditions.

Preterm infants with very low birth weight1500 g (VLBW) have a higher risk of developmental disorders. In addition to the common estimation of the mean intelligence values, we studied the distribution of intelligence at preschool age in VLBW infants and the risk factors influencing this distribution.A prospective cohort study of 277 VLBW infants32 weeks born in 1991-1995 and treated according to a standardized regimen in one Perinatal Center was carried out, including measurement of intelligence (Kaufman-Assessment Battery for Children) at age 5. Statistical methods employed were: explorative data analysis, correlation, chi (2)- and t-tests; the tested variables were: small for gestational age (third percentile), perinatal acidemia (umbilical arterial pH7.10), perinatal hypoxia (BE- 10), hypothermia (36 degrees C), hypoglycemia after the first day of life (30 mg / dL), bronchopulmonary dysplasia (FiO (2)0.21or = 36 weeks), intraventricular hemorrhage, ventricular dilation, periventricular leukomalacia, seizures, abnormal acoustic evoked potentials, and hyperexcitability at discharge.The distribution of intelligence in 137 VLBW infants32 weeks (60 % follow-up rate) was similar to a symmetrical Gaussian bell curve. The intelligence increased very slightly with birth weight (Pearson correlation: 0.172; p = 0.045) and was significantly lower in children with hypoglycemia after the first day of life (- 13.35; 95 % confidence interval: - 20.08 to - 6.63; p = 0.002), hyperexcitability at discharge (- 16.28; 95 % confidence interval: - 25.26 to - 7.31; p = 0.005), and bronchopulmonary dysplasia (- 7.00; 95 % confidence interval - 11.71 to - 2.29; p = 0.039).At preschool age, the intelligence of VLBW infants is normally distributed and correlates only slightly with the very low birth weight. Hypoglycemia after the first day of life and bronchopulmonary dysplasia are risk factors for lower intelligence. Hyperexcitability at discharge seemed to represent a promising prognostic factor for a later intelligence reduction.

Electrophoretic/electroosmotic light scattering experiments are reported. Particular emphasis is attributed to the various effects resulting from (a) the electro-osmotic mobility μ eo due to added indifferent electrolyte, (b) the dependence of μ eo on the pH, (c) the influence of coating the cell walls and particles with the macromolecule poly-DADMAC, (d) contracting the double layers, (e) the duration of the coating process and (f) the switching frequency of the external electric field.

For three different types of polymer latex particles with widely different particle charges the structure of suspensions before and after crystallization is investigated. A liquid-like ordered state was achieved by shear melting crystal-like ordered samples. The structure factors S(Q) of the liquid-like suspensions are analyzed in terms of the resealed mean spherical approximation (RMSA) of Hansen and Hayter. The Bragg diffraction pattern of the crystallized samples shows that the structure is b.c.c. It is found that the particle number concentration n and the distance of nearest neighbours in corresponding liquid- and crystal-like states differ by less than 4 %. In the second part of the paper, Bragg diffraction was used to determine the crystallite size distribution in samples of different particle concentration.

Differentiation of non-haemorrhagic subependymal pseudocysts from subependymal pseudocysts after cerebral haemorrhage in the preterm infant.Selective ultrasonographic screening in 2200 neonates and retrospective analysis in 72 infants with subependymal pseudocysts, the full-term infants being analysed from birth, and the preterm infants after the second week of life, thus avoiding the gestational age at which cerebral haemorrhage occurs in the preterm infant.Three variants of pseudocysts were identified: the caudothalamic germinolysis is a leukomalacic and pseudocystic gliosis. Pseudocysts in the anterior choroid plexus of the lateral ventricle could be distinguished from caudothalamic germinolysis by their location, form and movement. Pseudocysts lateral of the frontal horns are the result of regression of germinal matrix remains.Differentiation of non-haemorrhagic from post-haemorrhagic germinolysis is necessary to clarify the aetiology and pathogenesis of non-haemorrhagic pseudocysts. Caudothalamic germinolysis possibly is the result of infection with stenotic intima proliferation following vasculitis. The results are thalamostriatal vasculopathy and germinal necrosis. Anterior plexus cysts might be the result of folding faults of the ependyma in the growth period of the choroid plexus. Pseudocysts lateral of the frontal horns should not be mistaken for ventricular ligaments.

In this contribution we investigate whether the structure of concentrated shear-ordered dispersions as determined by small angle synchrotron x-ray or neutron scattering can be rationalized in terms of viscoelastic flow behavior as in rheological investigations. Although so far scattering experiments have contributed little to the understanding of rheological systems we are convinced that rheological investigations will profit considerably from a better knowledge of the micro-structure of the dispersions. Sheared dispersions are usually ordered in layers. There are two kinds of ordering of interest: (a) The structure in a layer (b) The structure between the layers. One interesting point of mesogenic systems is their viscoelastic nature. There is strong evidence that the structure in a layer (a) can be treated as elastic or solid-like, whereas the structure (b) between the layers seems to be fluid-like. With scattering experiments one is in the excellent position that two experiments exist with which the two effects can be investigated separately: The solid-like microstructure (a) can be determined at perpendicular incidence. The fluid-like microstructure (b) is given by the scattering intensity along certain Bragg rods (3n±1-rods). In particular this second micro-structure may change in time by aging.

We report our experience of pacemaker treatment in a premature infant of 832 grams with congenital complete atrioventricular block due to maternal Sjögren's Syndrome. She was delivered by cesarean section at an estimated gestational age of 26 weeks because of fetal bradycardia, decreasing fetal movements and hydrops. Immediate postnatal transesophageal ventricular pacing was not successful, whereas transthoracic pacing with self-adhesive patch electrodes adapted to body size resulted in an effective increase of the infant's heart rate until operative application of temporary epimyocardial pacing wires ensured the external stimulation of the heart.

Although nonoliguric hyperkalemia of the premature infant is a common problem, in many hospitals it is not observed. It is characterized by an excessive increase in serum potassium concentration (serum-[K (+)]) at 24 hours after birth. Recently, salbutamol has been recommended to treat hyperkalemia. There are no controlled trials in premature infants. During the first minutes of salbutamol infusions paradoxical increases in serum-[K (+)] may occur. We asked for possible reasons for the variable incidence of the disorder. We wanted to know if salbutamol is currently applied and if initial increases in serum-[K (+)] during salbutamol infusions have been observed.National survey in Germany.Questionnaires of 132 hospitals caring for premature infants30 gestational weeks. The incidence of hyperkalemia was 0 - 40 %. At least 25 % of all hospitals measured serum-[K (+)] not before the second day after birth. 52 hospitals had applied salbutamol. Nine hospitals reported increases in serum-[K (+)] associated with salbutamol therapy. However, it was common practice to measure serum-[K (+)] 1 hour (median, range 0.25 - 12 hours) after the start of the infusion. Two cases of cardiac arrhythmias during salbutamol infusion were reported.The variable incidence of hyperkalemia may result from the fact that many hospitals do not measure serum-[K (+)] on the first day after birth. Common practice made it potentially impossible to determine the frequency of initial increases in serum-[K (+)] during salbutamol infusion. However, these data should be available, before controlled trials on salbutamol treatment in premature infants can be initiated.

Autoantibodies against 52/60kD-Ro proteins, frequently present in patients with Sjoegren's Syndrome or systemic lupus erythematosus, are transmitted to the fetus during pregnancy. These autoantibodies can damage the cardiac conductive system of the fetus and cause a complete atrioventricular block, with a mortality of 30 %. We report the intrauterine therapy during four pregnancies of the same mother with high 52/60kD-Ro autoantibodies and the outcome of her infants. Our patient with primary Sjoegren's Syndrome suffered an early miscarriage during her first pregnancy. During the second pregnancy, a fetal atrioventricular block was observed at 23 weeks of gestation. Although subsequently dexamethasone therapy and daily plasmaphereses were started, a cesarean section was necessary at 26 weeks due to hydrops fetalis. The girl died from the atrioventricular block after two days. During the third and fourth pregnancies, dexamethasone therapy was begun already at 7 weeks, and regular plasmaphereses at 15 weeks. The children were delivered by cesarean section at 32 and 36 weeks because of growth retardation. Both had normal electrocardiograms after birth and after 2 and 4 years. In pregnant women with connective tissue diseases, monitoring of anti Ro-autoantibodies and fetal heart function is important. Intrauterine therapeutic options are dexamethasone therapy to suppress maternal and fetal inflammatory reactions and repeated plasmaphereses to reduce autoantibody levels. Postnatal follow up of the infants for atrioventricular block and rheumatic manifestations is necessary.

We review the efficacy of oral sugar solutions for treating procedural pain in neonates and address the following questions: Do newborns need analgesic therapy for procedural pain during blood sampling? How do sugars influence pain-reactions of neonates? What is the efficacy of sugar solutions in clinical practice?We searched for relevant articles in the PubMed database from 1990 to September 2000.Treatment of procedural pain in newborns is desirable because they are more sensitive to pain than adults, they show marked pain reactions during blood sampling and repeated acute pain in the newborn period results in longterm behavioural changes. Oral sugar solutions have been studied for treatment of procedural pain in neonates. Their initial effect is the result of orotactile stimulation by the intraoral fluid. The orogustatory stimulation by the sweet taste prolongs the effect for up to 10 minutes through endorphin release. In randomized-controlled trials oral sugar solutions (2 ml of 25% sucrose or 30% glucose) reduced pain reactions and crying and attenuated the heart rate increase after capillary and venous blood sampling in term and preterm neonates. They are more effective than traditional calming strategies, like cuddling by parents, use of a pacifier, or breast feeding. Yet, sugar solutions provide no adequate analgesia for more severe pain, e.g. during circumcision.Sugar solutions effectively relieve procedural pain during blood sampling in neonates. Additional studies are needed to determine the minimal effective dose and the efficacy and side effects of repeated sugar doses in the same patient.

This prospective study reports on the prevalence of hearing impairment in an at-risk neonatal intensive care unit (NICU) population.From 1990 to 1998, 1062 neonates were screened with the use of transitory evoked otoacoustic emissions (TEOAE) and brainstem evoked response audiometry (BERA).934 infants passed the primary screen for both ears, 75 for one ear, adding up to 95%. 17 infants (1.6%) were lost to follow-up. In fourteen infants (1.3%), bilateral hearing impairment above 30 dB was confirmed. While all children with hearing impairment belonged to the group of 862 children receiving aminoglycosides, only one of them presented no other risk factors. In twelve of the hearing impaired children other anamnestic factors, i.e. dysmorphism, prenatal rubella or cytomegaly, family history of hearing loss or severe peri- and postnatal complications seem to be more probable causes of the identified hearing loss. In one of these children, delayed onset or progression of hearing loss is suspected.From our data, aminoglycosides are not an important risk factor for hearing impairment, when serum levels are continuously monitored, as in our cohort. After adjustment for other risk factors, birth weight between 1000 gr and 1500 gr and a gestational age between 29 and 31 weeks were no predictive markers for hearing impairment. It might be speculated that the improved medical treatment in a NICU reduces the probability of hearing impairment for those two groups. Conductive hearing loss as a possible additional cause for hearing impairment was not studied in detail, but the high percentage of malformations detected (four out of fourteen hearing impaired infants) demands further monitoring, close follow-up, adequate treatment and counselling.

Mothers are offered skin-to-skin contact with their preterm infants with the intention to promote bonding. But it is not known if the mother of a very immature fragile infant perceives skin-to-skin contact as a helpful intervention or a stressful situation.Mothers of singleton preterm infants (gestational age 27-30 weeks) began skin-to-skin contact as soon as the infant was breathing spontaneously. They prospectively documented frequency and duration of skin-to-skin contact, they rated their anxiety or confidence and their attachment to the infant and described their observations of the infant daily for 14 days in a semi-structured questionnaire.17 of 25 mother-infant-pairs in the observation period fulfilled the entry criteria, 14 questionnaires about 196 skin-to-skin periods could be analyzed (median gestational age 27.5 weeks (27-30), median birth weight 1130 g (695-1300). Skin-to-skin contact began at a median age of 3 days [2-7]. The median duration of the skin-to-skin periods was increased at maternal request from 60 to 120 minutes between day 1 and 14 (p = 0.004). Even then 21% of the mothers wanted a still longer duration of skin-to-skin contact. Mothers reported anxiety only 5 times. 82% of the mothers reported positive own feelings during skin-to-skin contact and 78% felt that skin-to-skin contact increased their attachment to their infant.The mothers studied perceived skin-to-skin contact with their very immature infants as a positive and helpful intervention. Skin-to-skin contact took place regularly and for increasing periods of time.