Thesis (MCurr)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Intraventricular haemorrhage is associated with neurological morbidity and mortality in low birth weight infants. In spite of improvements in treatment to reduce the incidence of the haemorrhage, the condition continues to remain a major cause of long term morbidity in low birth weight infants. The evidence from the literature has shown that low birth weight infants might benefit from delayed cord clamping particularly in reducing the risk of intraventricular haemorrhage and its neurological consequences. The primary objective of this review was to assess the effects of delayed versus early cord clamping on intraventricular haemorrhage amongst low birth weight infants. The secondary objectives were to evaluate the effects of delayed versus early cord clamping on the Apgar scores, hyperbilirubinaemia and polycythaemia in infants. The following electronic databases were searched: CINAHL, MEDLINE (searched via PubMed) and Cochrane Central Register of Controlled Trials (CENTRAL). Other information was gathered from the reference lists of retrieved articles and relevant experts. The selection criteria entailed all randomised controlled trials comparing delayed versus early cord clamping following birth in infants with low birth weight. Two reviewers independently extracted the data and assessed the quality of the trials. Disagreements on studies for inclusion were resolved by discussion with the third reviewer. The review included five randomised controlled trials with 215 participants. The risk of intraventricular haemorrhage was significantly reduced in the delayed compared with early cord clamping (RR0.52, 95% CI 0.33 to 0.82, P=0.005). No statistically significant difference was shown between delayed versus early cord clamping for the risk of hyperbilirubinaemia (RR O.48, 95% CI -0.43 to 1.39, P=0.30). There was no data available for other comparisons: Polycythaemia and Apgar scores. There is growing evidence that delayed cord clamping might benefit low birth weight infants. In the included studies, delayed cord clamping for at least 30 seconds appear to have a potential in reducing the risk of intraventricular haemorrhage. The results of this review should however be interpreted with caution due to a limited number of studies with the absence of clinically important secondary outcomes in the included trials. Further research is required on large scale randomised controlled trials. / AFRIKAANSE OPSOMMING: Intraventrikulêre bloeding word geassosieer met neurologiese morbiditeit en mortaliteit in suigelinge met ’n lae geboortegewig. Ten spyte van die verbetering in die behandeling om die gevalle van bloeding te verminder, duur die toestand voort as ’n belangrike oorsaak van langtermyn morbiditeit in lae gewig geboortes. Bewyse uit die literatuur toon dat suigelinge met ’n lae geboortegewig voordeel mag trek uit vertraagde afklemming, veral deur die vermindering van die risiko van intraventrikulêre bloeding en die neurologiese gevolge daarvan. Die primêre doelwit van hierdie navorsing was om die effek van vertraagde, versus vroeë afklemming op intraventrikulêre bloeding onder suigelinge met ’n lae geboortegewig te bepaal. Die sekondêre doelwit is om die effekte van vertraagde, versus vroeë afklemming op die Apgar uitslae, hiperbilirubinaemia en polisitaemia by suigelinge te evalueer. Die volgende elektroniese databasisse is nagegaan: CINAHL, MEDLINE (soektog via PubMed); Cochrane Central Register of Controlled Trials (CENTRAL). Ander inligting is verkry uit die bronnelyste van nagevorsde artikels en van relevante deskundiges. Die seleksie kriteria behels alle ewekansige beheerde toetsing, insluitende toekomstige studies wat vertraagde, versus vroeë afklemming vergelyk by suigelinge met ’n lae geboortegewig. Twee resensente het onafhanklik data geneem en die kwalititeit van die toetse bepaal. Verskille oor insluiting van navorsing, is met ’n derde resensent deur middel van bespreking opgelos. Die navorsing het vyf ewekansige beheerde steekproewe met 215 deelnemers ingesluit. Die risiko van intraventrikulêre bloeding is beduidend verminder in die vertraagde gevalle, in teenstelling met vroeë afklemming (RR0.52, 95% CI 0.33 tot 0.82, P=0.005). Geen statistiese beduidende verskil is bewys tussen vertraagde teenoor vroeë afklemming ten opsigte van hiperbilirubinaemia nie (RR 0.48, 95% CI – 0.43 tot 1.39, P=0.30). Daar was geen data beskikbaar vir ander vergelykings nie: Polisytaemia en Apgar uitslae. Daar is groeiende bewyse dat vertraagde afklemming lae geboortegewig suigelinge mag beïnvloed. Dit wil in die ingeslote studies voor kom dat vertraagde afklemming van ten minste 30 sekondes die potensiaal het om die risiko van intraventrikulêre bloeding te verminder. Die uitslae van hierdie beskouing sal nietemin met omsigtigheid geïnterpreteer moet word, weens die beperkte aantal studies met die afwesigheid van klinies belangrike sekondêre uitkomste in die ingeslote proewe. Verdere navorsing word benodig op grootskaalse ewekansige beheerde proewe.

Haemorrhage within the germinal matrix with extension into the ventricle is commonly seen in very low birth weight babies. Outcome following severe haemorrhage, in particular when associated with post haemorrhagic hydrocephalus and congestive venous infarction is poor, whilst outcome following moderate degrees of haemorrhage remains variable. The Neural Stem Progenitor Cells (NSPC) within the GM have been shown to be exquisitely sensitive to micro-environmental cues, as such, haemorrhage within the GM is postulated to impact on neurological outcome through aberration of normal NSPC behaviour. Here we have developed a stereotactic model of autologous blood injection which recapitulates key features of Papile grade II/III Germinal Matrix Haemorrhage / Intraventricular Haemorrhage (GMH/IVH). This model demonstrates that GMH/IVH causes an activation of the NSPC within the wall of the lateral ventricle and increases the number of transient amplifying cells within the transcallosal pathway. Further to this RNA extraction from the NSPC (selected using a CD133 MACS protocol) revealed that GMH/IVH causes a significant down regulation of the transmembrane receptor Notch, a finding that was validated using Hes5 in situ hybridisation (ISH). Using a battery of behavioural tests including assessment of developmental landmarks, neuromotor and reflex development we found that GMH/IVH causes subtle but significant impacts on early neonatal development. GMH/IVH in transgenic mice overexpressing the polycomb group gene Bmi1 in NSC (Nestin+ve) revealed increased self-renewal and resistance to oxidative stress (properties of Bmi1 overexpression) reduced the impact of GMH on the oligodendrocyte population, it also revealed a unique behavioural phenotype. We propose that GMH/IVH down regulates Notch in the NSPC causing a burst of precocious proliferation and depleting the NSPC pool, which impacts on neurological outcome due to altered cortical architecture. Further we suggest that modulation of NSPC properties may play role in determining outcome and should be further explored for its therapeutic potential.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22882号 / 医博第4676号 / 新制||医||1047(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 髙折 晃史, 教授 濵﨑 洋子, 教授 羽賀 博典 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Left ventricular diastolic dysfunction (LVDD) is any abnormality in the filling of the left ventricle (LV).  Despite the prevalence of this disease, it remains difficult to diagnose, mainly due to inherent compensatory mechanisms and a limited physical understanding of the filling process.  LV filling can be non-invasively imaged using color m-mode echocardiography which provides a spatio-temporal map of inflow velocity.  These filling patterns, or waves, are conventionally used to qualitatively assess the filling pattern, however, this work aims to physically quantify the filling waves to improve understanding of diastole and develop robust, reliable, and quantitative parameters. This work reveals that LV filling waves in a normal ventricle act as dispersive waves and not only propagate along the length of the LV but also spread and disperse in the direction of the apex.  In certain diseased ventricles, this dispersion is limited due to changes in LV geometry and wall motion.  This improved understanding could aid LVDD diagnostics not only for determining health and disease, but also for distinguishing between progressing disease states. This work also identifies a limitation in a current LVDD parameter, intra ventricular pressure difference (IVPD), and presents a new methodology to address this limitation.  This methodology is also capable of synthesizing velocity information from a series of heartbeats to generating one representative heartbeat, addressing inaccuracies due to beat-to-beat variations.  This single beat gives a comprehensive picture of that specific patient's filling pattern.  Together, these methods improve the clinical utility of IVPD, making it more robust and limiting the chance for a misdiagnosis. / Master of Science

Purpose: This study sought to determine the previously undescribed cytologic and metabolic alterations that accompany endoscopic third ventriculostomy with choroid plexus cauterization (ETV/CPC). Methods: Cerebrospinal fluid (CSF) samples were collected from infant patients with hydrocephalus at the time of index ETV/CPC and again at each reintervention for persistent hydrocephalus. Basic CSF parameters, including glucose, protein, and cell counts, were documented. A multivariable regression model, incorporating known predictors of ETV/CPC outcome, was constructed for each parameter to inform time-dependent normative values. Results: A total of 187 infants were treated via ETV/CPC for hydrocephalus; initial laboratory values were available for 164 patients. Etiology of hydrocephalus included myelomeningocele (53, 32%), intraventricular hemorrhage of prematurity (43, 26%), aqueductal stenosis (24, 15%), and others (44, 27%). CSF parameters did not differ significantly with age or etiology. Glucose levels initially drop below population average (36 to 32 mg/dL) post-operatively before slowly rising to normal levels (42 mg/dL) by 3 months. Dramatically elevated protein levels post-ETV/CPC (baseline of 59 mg/dL up to roughly 200 mg/dL at 1 month) also normalized over 3 months. No significant changes were appreciated in WBC. RBC counts were very elevated following ETV/CPC and quickly declined over the subsequent month. Conclusion: CSF glucose and protein deviate significantly from normal ranges following ETV/CPC before normalizing over 3 months. High RBC values immediately post-ETV/CPC decline rapidly. Age at time of procedure and etiology have little influence on common clinical CSF laboratory parameters. Of note, the retrospective study design necessitates ETV/CPC failure, which could introduce bias in the results.

The regulation of surface tension (ST) by surfactants plays an important role in the human respiratory system but is largely unexplored in brain homeostasis. The aim of this study was to evaluate changes in ST in relation to surfactant proteins (SPs) in children with intraventricular hemorrhage (IVH). CSF samples from 93 patients were analyzed for ST with a force tensiometer and SP-A-D and -G with ELISA assays. Patients belonged to six groups: (i) IVH before primary intervention (PI), (ii) IVH 4–28 days after PI, (iii) IVH 44–357 days after PI, (iv) hydrocephalus, (v) sepsis and (vi) controls. We found indirect correlations and significant differences in ST and SPs (all p < 0.001; except for SP-C, p = 0.007). Post hoc analyses showed significantly decreased ST in IVH patients before PI compared with patients with hydrocephalus, sepsis or controls (p < 0.001), but it increased in IVH patients over time. All SPs were significantly elevated when comparing IVH patients before PI with controls (all p < 0.001; except for SP-C, p = 0.003). Children suffering from IVH displayed an increase in SPs and a decrease in ST as coping mechanisms to preserve CSF flow. The increase in ST over time could serve as prognostic marker for the healing process.

The regulation of surface tension (ST) by surfactants plays an important role in the human respiratory system but is largely unexplored in brain homeostasis. The aim of this study was to evaluate changes in ST in relation to surfactant proteins (SPs) in children with intraventricular hemorrhage (IVH). CSF samples from 93 patients were analyzed for ST with a force tensiometer and SP-A-D and -G with ELISA assays. Patients belonged to six groups: (i) IVH before primary intervention (PI), (ii) IVH 4–28 days after PI, (iii) IVH 44–357 days after PI, (iv) hydrocephalus, (v) sepsis and (vi) controls. We found indirect correlations and significant differences in ST and SPs (all p < 0.001; except for SP-C, p = 0.007). Post hoc analyses showed significantly decreased ST in IVH patients before PI compared with patients with hydrocephalus, sepsis or controls (p < 0.001), but it increased in IVH patients over time. All SPs were significantly elevated when comparing IVH patients before PI with controls (all p < 0.001; except for SP-C, p = 0.003). Children suffering from IVH displayed an increase in SPs and a decrease in ST as coping mechanisms to preserve CSF flow. The increase in ST over time could serve as prognostic marker for the healing process.:1. Einführung 3 1.1 Intraventrikuläre Hämorrhagie 3 1.1.1 Allgemeiner Überblick 3 1.1.2 Pathogenese 3 1.1.3 Risikofaktoren und Prävention 4 1.1.4 Klinik 5 1.1.5 Komplikationen 6 1.1.6 Behandlungsoptionen bei IVH und PHVD 7 1.1.6.1 Medikamente 7 1.1.6.2 Interventionen 7 1.2 Surfactant und Surfactant-Proteine 8 1.3 Zusammenfassung der IVH-Problematik und Fragestellungen der Dissertation 11 2. Publikationsmanuskript 13 3. Zusammenfassung der Arbeit 28 4. Literaturverzeichnis 32 5. Abkürzungsverzeichnis 39 6. Anlagen der Originalpublikation 41 7. Darstellung des eigenen Beitrags 48 8. Erklärung über die eigenständige Abfassung der Arbeit 49 9. Lebenslauf 50 10. Publikationen 51 11. Danksagung 52

Abstract The aim of the study was to evaluate the efficacy and safety of antenatal and postnatal corticosteroids in the prevention for mortality and acute and long-term morbidity in preterm infants. Altogether 109 eligible preterm infants participated in a randomized, multi-center, double-blinded controlled trial studying the efficacy of early dexamethasone (DX) treatment. The infants received either four doses of DX or placebo. DX treatment did not have a detectable influence on survival without bronchopulmonary dysplasia (BPD), severe intracranial hemorrhage, or periventricular leukomalacia. In a meta-analysis of 15 trials, we found that early prolonged DX treatment (> 96 h, n = 1594 infants) decreased the risk of BPD (RR 0.72 95% CI 0.61–0.87), whereas early short DX course did not (n = 1069 infants). However, prolonged DX increased the risk of gastrointestinal (GI) complications (RR 1.59 95% CI 1.02–2.46). Fifty-one very preterm infants participated in a randomized placebo-controlled trial studying early hydrocortisone (HC) started before 36 hours of age and continued for 10 days. The basal and stimulated serum cortisol levels were measured before the intervention. The study was interrupted because of GI perforations in the HC group. HC decreased the risk of patent ductus arteriosus. HC-treated infants with serum cortisol concentrations above the median had a high risk of GI perforation. HC increased survival without BPD among infants with low endogenous cortisol levels. Altogether 45 surviving infants were enrolled in the follow-up of the early HC trial at 2 years of age. None of the study patients had died after discharge. There was no difference in the recorded rehospitalization rate, growth characteristics, or neurological development between HC and placebo-treated children. Altogether 249 women pregnant at less than 34.0 gestational weeks participated in a randomized trial studying the efficacy of a single additional dose of betamethasone (BM). All of the 159 infants in the BM group and 167 in the placebo group were born before 36 weeks of gestation. Intact survival was comparable between the BM and placebo groups, whereas the need for surfactant therapy in RDS was increased in the BM group. According to a post hoc analysis of 206 infants delivered within 1–24 hours, the BM booster tended to increase the risk of RDS and to decrease intact survival.

No description available.

Human mesenchymal stem cell (MSC) therapy has shown neuroprotective effects and improvement on recovery from neonatal intraventricular hemorrhage (IVH). This study focused on histological evaluations of human amniotic fluid MSC therapy during early prenatal life in a preterm IVH rabbit model. IVH was diagnosed at 24 h of age with ultrasound and animals were randomized into subgroups with confirmed IVH and an IVH negative control group. Animals with confirmed IVH received vehicle only or MSCs at two different doses via intraperitoneal administration. The animals were sacrificed at 48 h post administration. The severity of IVH was histologically analyzed via staining of endogenous peroxidase activity in cryosections and the distribution of red blood cells and cell-free hemoglobin was scored. Primary antibodies targeting human epitopes were validated in IHC assays of frozen MSC pellet. An anti-human nuclear mitotic apparatus (hNuMA) antibody labeled the majority of cells in the MSC pellet and did not cross-react with rabbit NuMA when tested in the nontreated rabbit brain. Significant levels of red blood cells and cell-free hemoglobin were found in the IVH confirmed group, whereas the control group showed no hemorrhage. The MSC therapy groups showed similar scoring results as the IVH-vehicle group. Anti-hNuMA immunolabeling did not detect any cells in the brain of MSC treated rabbits. However, extracellular (nonnuclear) immunolabeling was detected, located in the midbrain of the animals that received MSCs, indicating the presence of MSC nuclear debris. The preterm rabbit model was proven successful for inducing IVH, whereas MSC treatment did not affect the degree of hemorrhage. To increase the possibility to detect the MSCs post administration, future studies should include prelabeling of the MSCs with a suitable cell tracker and analyses at time points closer to the administration of MSCs. / Human mesenkymal stamcellsterapi har visat neuroprotektiva effekter samt förbättring av återhämtning efter neonatal intraventrikulär blödning (IVH). Denna studie fokuserade på histologiska utvärderingar av stamcellsterapi med humana mesenkymala stamceller (MSC) från fostervatten under tidigt prenatalt liv i en prematur IVH-kaninmodell. IVH diagnostiserades med ultraljud vid 24 tim. ålder och djuren delades slumpmässigt in i undergrupper med konfirmerad IVH och en IVH-negativ kontrollgrupp. Djur med konfirmerad IVH mottog endast bärmedel eller MSC i två olika doser via intraperitoneal administration. Djuren avlivades 48 tim. post administration. Graden av IVH analyserades histologiskt genom färgning av peroxidasaktivitet i kryosnitt av hjärna och distributionen av erytrocyter samt fritt hemoglobin graderades. Primärantikroppar riktade mot humana epitop validerades i immunhistokemiska analyser av fryst MSC-pellet. En anti-human nukleär mitotisk apparat (hNuMA) antikropp märkte majoriteten av cellerna i MSC-pelleten och korsreagerade inte med kanin-NuMA under försök i obehandlad kaninhjärna. Signifikanta nivåer av erytrocyter och fritt hemoglobin påvisades i gruppen med konfirmerad IVH, medan kontrollgruppen inte visade någon blödning. Samtliga IVH-grupper; IVH-vehicle och de som mottog MSC- terapi, visade liknande blödningsgrad. Anti-hNuMA-immuninmärkning kunde inte detektera några celler i de MSC-behandlade kaninhjärnorna. Dock detekterades extracellulär (icke-nukleär) immuninmärkning lokaliserad i mitthjärnan hos de djur som mottog MSC, vilket indikerar närvaro av nukleär MSC-debris. Den prematura kaninmodellen bevisades vara framgångsrik för induktion av IVH, men MSC-terapi påverkade inte blödningsgraden. För att öka sannolikheten att detektera MSC efter administration, borde framtida studier inkludera förmärkning av MSC med en lämplig cellmarkör samt analyser vid tidpunkter närmare administrationen av MSC.