Eine Erhöhung des Bilirubins über 2 mg/dl betrifft 90 % aller Neugeborenen. Sie ist meist physiologisch und tritt optisch sichtbar bei 60-70 % dieses Kollektivs auf. In der pathologischen, exzessiv erhöhten Form ist sie der häufigste Grund für eine stationäre Wiederaufnahme während der ersten sieben Lebenstage. Ihre schwerste Komplikation, der Kernikterus, scheint - trotz allgemein verfügbarer, preiswerter und sicherer Therapiemöglichkeiten - wieder vermehrt aufzutreten. Die Gründe liegen im Überwachungsdefizit bei früher Entlassung von schlecht aufgeklärten Eltern, Nichtbeachtung der Besonderheiten der Neugeborenen ≤ 38 Schwangerschaftswochen und der zunehmenden Tendenz zum Stillen bei häufig unzureichender Anleitung. Ferner werden ikterische Kinder nur zu oft lediglich visuell bezüglich des Grades der Bilirubinämie eingeschätzt und die Therapie somit erheblich verzögert. Gegenstand dieser Arbeit ist die Frage, ob aus der Dynamik des Serumbilirubinspiegels von der Geburt bis zum 3. Lebenstag die Wahrscheinlichkeit des Auftretens einer phototherapiepflichtigen Hyperbilirubinämie abgeschätzt werden kann. Dazu wurde der Serumbilirubinspiegel direkt postnatal aus dem Nabelschnurblut, bzw. am 3. Lebenstag gleichzeitig mit dem Stoffwechselscreening ermittelt und der Phototherapiebedarf im Verlauf festgehalten. Um die Aussage zu präzisieren, wurde die Studienpopulation aus 2573 Kindern weiter unterteilt in 2180 reife tAGA- (hier Eu- und Hypertrophe), 267 reife tSGA-Kinder (Hypotrophe) und 126 FG (Frühgeborene). In allen 3 Gruppen korrelierten das Nabelschnurbilirubin und der Serumbilirubinwert vom 3. Lebenstag positiv mit der Entwicklung einer Hyperbilirubinämie. Anhand dieser Ausgangswerte konnten Grenzen für Hoch-, Mittelhoch-, Mittelniedrig- und Niedrigrisikogruppen definiert werden, welche die Entwicklung einer Hyperbilirubinämie mit einer Wahrscheinlichkeit von ≥ 20 %, 5-20 %, 0 < x <5 % und 0 % voraussagen. Damit kann man bereits früh eine Vorabselektion entsprechend dem Gefährdungspotential treffen und die Verlaufskontrollen entsprechend terminieren. Als Risikofaktoren einer therapiepflichtigen Hyperbilirubinämie wurden außerdem Frühgeburtlichkeit, seltener tSGA, geringes Geburtsgewicht und niedriges Gestationsalter (in der vorliegenden FG-Gruppe nicht signifikant) gefunden. Im Falle einer Sectiogeburt und bei Zuhilfenahme von Hilfsmitteln im Rahmen einer vaginalen Entbindung nahm der Bedarf an Phototherapie in der tAGA- und tSGA-Gruppe zu.:Bibliographische Beschreibung……………………………………………………………………….1 Abkürzungsverzeichnis………………………………………………………………………………..2 1. Einleitung…………………………………………………………………………………...3 1.1. Geschichtliche Entwicklung……………………………………………………………………...3 1.2. Wandel der Anschauungen zu den Therapiegrenzen…..…………………………….................4 1.3. Hyperbilirubinämie……………………………………………………………………………….7 1.4. Kernikterusregister………………………………………………………………………………..8 1.5. Problemstellung…………………………………………………………………………………...9 2. Patienten und Methoden………………………………………………………………..11 2.1. Patientenkollektiv………………………………………………………………………………...11 2.2. Ausschlusskriterien………………………………………………………………………………11 2.3. Datenerfassung………………………………………………………………………………...…11 2.4. Phototherapie (PT)………………………………………………………………………………12 2.5. statistische Analyse………………………………………………………………………………13 2.5.1. konkrete Fragestellung………………………………………………………………………………...…13 2.6. Signifikanzniveau……………………………………………………..………………………….13 3. Ergebnisse………………………………………………………………………………..14 3.1. Gesamtpopulation…………………………………………………………….………………….14 3.2. Charakteristika der Studienpopulation…………………………….…………………………..14 3.3. tAGA (reife eu- und hypertrophe Neugeborene)………………………………………………16 3.4. tSGA (reife hypotrophe Neugeborene).……….……………………………………………….18 3.5. Frühgeborene (FG)………………………………..…………………………….……………….20 3.6. direkter Vergleich der 3 Untergruppen (tAGA, tSGA und FG)…………………………...…22 3.7. Charakteristika der Population der zweiten Studienphase…………………………………...28 3.8. tAGA-Kinder in der zweiten Studienphase (TSB3-tAGA)……………………………………30 3.9. tSGA in der zweiten Studienphase (TSB3-tSGA)….…………………………………………..32 3.10. Frühgeborene in der zweiten Studienphase (TSB3-FG)……………….…………………….35 3.11. direkter Vergleich der drei Untergruppen der zweiten Studienphase…………….………..37 3.12. Vergleich der retro- und prospektiven Teile der Studie…….……………………………….43 3.13. Die Phototherapiegruppe………………………………………………………………………45 3.13.5. Zusammenhang zwischen Phototherapie und Geburtsmodus………………………………………..47 3.13.6. Zusammenhang zwischen Phototherapie und Nabelschnurbilirubin………………………………..48 3.13.7. Zusammenhang zwischen Phototherapie und Serumbilirubin vom 3.LT (TSB3)…………………..51 3.14. Vorhersage der therapiepflichtigen Hyperbilirubinämie anhand der Nabelschnurbilirubin-Werte…..………………………………………………….…………………………………….……..54 3.14.1. statistische Begriffe………………………………………………………………………………………54 3.14.2. Vorhersage der therapiepflichtigen Hyperbilirubinämie anhand der Nabelschurbilirubin-Werte.54 3.15. Vorhersage der therapiepflichtigen Hyperbilirubinämie anhand TSB3 (Serumbilirubin vom 3. Lebenstag)……………………...………………………………………..……………………56 3.16. Zusammenhang zwischen NS-Bili und TSB3(Serumbilirubin vom 3. Lebenstag)…………58 3.17. Regressionsanalyse…………………………………...…………………………………………59 3.17.1. univariate Regressionsanalyse………………………………………………………………………….59 3.17.2. multivariate Regressionsanalyse………………………………………………………………………..59 3.18. Odds Ratio einer therapiepflichtigen Hyperbilirubinämie………………………………….61 3.19. Beginn und Dauer der Phototherapie…………………………………………………………62 4. Diskussion……………………………………….…………………………………..…….64 Nabelschnurbilirubin und Phototherapie………………………………………………….……….64 Serumbilirubin vom 3. Lebenstag und Phototherapie….………………………………………….67 Kombination aus Nabelschnurbilirubin und Serumbilirubin vom 3.Lebenstag…………………71 Phototherapiegruppe…………………………………………………………………………………73 Schlussfolgerung…………………………...…………………………………………………………76 5. Zusammenfassung der Arbeit……………………………………………………………78 6. Literaturverzeichnis………………………………………………………………………82 7. Abbildungsverzeichnis……………………………………………………………………98 8. Tabellenverzeichnis……………………………………………………………………….99 Erklärung über die eigenständige Abfassung der Arbeit…………………………..……101 Danksagung…………………...…………………………………………………..………..102 Lebenslauf……………………………………………………………………………………………103

No description available.

In order to investigate the effect of food restriction on fat mobilization in horses with impaction in left ventral colon during treatment, serum triglycerides, NEFA and total bilirubine (TB) were measured before and after treatment. On another side, the determination of alcohol dehydrogenase (ADH) activity in serum could facilitate the distinguishing of the non-strangulating intestinal obstruction from the potential fatal strangulation obstruction and could submit a new prognostic biochemical parameter for intestinal strangulation. With the intention of giving a highlight over the analgesic effect of Buscopan® compositum in horses with colic, it was attempted to investigate the effect of Buscopan® compositum on the intestinal motility of healthy conscious horses in different regions of intestine. A significant elevation of NEFA and TB was observed in horses with impaction in left ventral colon at admission. By relieving the impaction, there was a significant elevation of triglycerides in comparison to its level at admission. There was a significant increase in ADH activity in all horses with acute intestinal obstruction. ADH activity was significantly higher in horses with strangulation in comparison to non-strangulation obstruction. There was only a significant correlation between ADH and lactate in horses with non-strangulation obstruction and colon torsion. Only AST and GLDH were significantly increased in horses with colon torsion. ADH activity > 20 U/l had 80.56% specificity and 80.49% sensitivity for discriminating horses with intestinal strangulation from non-strangulation obstruction. ADH activity < 80 U/l had 94.44% specificity and 66.67% sensitivity for survival. Buscopan® compositum had an immediate, rapid and significant (p< 0.05) reduction of duodenal, cecal and left ventral colon contractions after application. Cecal and left ventral colon contractions restored rapidly their normal contractions after 30 min, while duodenal contractions returned to the normal rate after 120 min of Buscopan® compositum administration. The horses with impaction in left ventral colon are susceptible to fat mobilization during the period of treatment as a result of food restriction. It was characterized by a revisable hypertri-glyceridemia and hyperbililrubinemia. Serum ADH activity could have a useful clinical value in detecting the intestinal strangulation and predicting the prognosis in horses with intestinal strangulation. Buscopan® compositum at its therapeutic dosage has an immediate, potent, short-lived reductive effect on cecum and left ventral colon contractions but a minor, longer effect on the duodenal contractions. Therefore, it is thought to be more effective in treatment of spasmodic colic than in large colon impaction.:Contents I List of Abbreviations II 1 Introduction and Literature 1 2 Results 4 2.1 Publication 1: Triglyceride, free fatty acids and total bilirubin in horses with left ventral large colon impaction 4 2.2 Publication 2: Clinical evaluation of serum alcohol dehydrogenase activity in horses with acute intestinal obstruction 9 2.3 Publication 3: Effect of Buscopan® compositum on the motility of the duodenum, cecum and left ventral colon in healthy conscious horses 43 3 Discussion 60 4 Summary 68 5 Zusammenfassung 70 6 References 72 7 Acknowledgement 81 / Um den Effekt der Nahrungskarenz auf die Fettmobilisation bei Pferden mit Verstopfung der linken ventralen Längslagen des Kolons während der Behandlung zu untersuchen, wurden Triglyceride (TG), freie Fettsäuren (FFS) und Gesamtbilirubin (GB) bestimmt. Andererseits ermöglicht die Bestimmung der Aktivität der Alkoholdehydrogenase (ADH) im Serum die Unterscheidung zwischen einer nichtstrangulierenden intestinalen Obstruktion und einer potentiell tödlichen Strangulation. ADH kann somit als ein neuer prognostischer biochemischer Parameter für die intestinale Strangulation eingesetzt werden. Um den spasmolytischen Effekt von Buscopan compositum bei Pferden mit Kolik zu untersuchen, wurde der Effekt von Buscopan compositum auf die intestinale Kontraktion von gesunden Pferden in verschiedenen Regionen des Darmes getestet. Eine signifikante Erhöhung der FFS und des GB wurde bei Aufnahme von Pferden mit einer Verstopfung in der linken ventralen Längslagen festgestellt. Nach der Behandlung der Verstopfung konnte eine signifikante Erhöhung der Konzentration von TG, bezogen auf die TG Konzentration bei Aufnahme in die Klinik, festgestellt werden. Bei Pferden mit akuter intestinaler Obstruktion wurde eine signifikante Erhöhung der Aktivität der ADH beobachtet. Die Aktivität der ADH war bei Pferden mit einer Strangulation signifikant höher als bei Pferden, die eine nichtstrangulierende Obstruktion des Darmes hatten. Bei Pferden mit einer nichtstrangulierenden Obstruktion oder einer Kolontorsion wurde eine positive Korrelation zwischen der ADH-Aktivität und der Laktatkonzentration im Serum festgestellt. Nur bei Pferden mit Kolontorsion waren die Aktivitäten von AST und GLDH signifikant erhöht. Für die Unterscheidung zwischen Pferden mit einer intestinalen Strangulation oder einer nichtstrangulierenden Obstruktion wurde für die ADH- Aktivität größer als 20 U/l eine Spezifität von 80,56% und eine Sensitivität von 80,49% ermittelt. Eine ADH-Aktivität kleiner 80 U/l zeigt, mit einer Spezifität von 94,44% und einer Sensitivität von 66,67%, eine günstige Prognose für das Überleben des Pferdes an. Nach Gabe von Buscopan® compositum trat eine sofortige schnelle und signifikante (p<0,05) Reduktion der Kontraktionen im Duodenum, Zäkum und den linken ventralen Längslagen ein. Die Kontraktionen des Zäkums und der linken ventralen Längslagen normalisierten sich schnell innerhalb von 30 min, wogegen die Kontraktionen des Duodenums erst 120 min nach der Applikation von Buscopan® compositum den Normalzustand erreichten. Pferde mit einer Verstopfung in der linken ventralen Längslagen des Kolons sind während der medizinischen Behandlung anfällig für Fettmobilisation aufgrund der reduzierten Futter-aufnahme. Dies ist gekennzeichnet durch eine reversible Hypertriglyceridämie und eine Hyperbilirubinämie. Die Aktivität von ADH im Serum kann ein nützlicher klinischer Parameter sein, um eine intestinale Strangulation zu identifizieren und bietet sich auch als prognostischer Marker bei intestinaler Strangulation an. Die Applikation von Buscopan® compositum in der therapeutischen Dosierung hat eine sofortige, potente und kurzzeitige Reduktion der Kontraktionen des Zäkums und der linken ventralen Längslage aber einen geringen und länger anhaltenden Effekt auf die duodenalen Kontraktionen zur Folge. Daraus folgt, dass Buscopan® compositum bei der Behandlung von Krampfkoliken effektiver ist als bei Verstopfungen des großen Kolons.:Contents I List of Abbreviations II 1 Introduction and Literature 1 2 Results 4 2.1 Publication 1: Triglyceride, free fatty acids and total bilirubin in horses with left ventral large colon impaction 4 2.2 Publication 2: Clinical evaluation of serum alcohol dehydrogenase activity in horses with acute intestinal obstruction 9 2.3 Publication 3: Effect of Buscopan® compositum on the motility of the duodenum, cecum and left ventral colon in healthy conscious horses 43 3 Discussion 60 4 Summary 68 5 Zusammenfassung 70 6 References 72 7 Acknowledgement 81

Background Cardiovascular diseases, including myocardial infarction and stroke, are the main reason of death in Sweden and Western Europe. High iron stores are believed to produce oxygen radicals, which is the presumed putative mechanism behind lipid peroxidation, atherosclerosis and subsequent cardiovascular disease. Iron levels are associated with the hemochromatosis associated HFE single nucleotide polymorphisms C282Y and H63D. Bilirubin is an antioxidant present in relatively high levels in the human body. Several previous studies have found an association between high bilirubin levels and a lower risk for cardiovascular disease. Bilirubin levels are highly influenced by the common promoter polymorphism TA-insertion UGT1A1*28, the main reason for benign hyperbilirubinemia in Caucasians. There is a lack of prospective studies on both the association of iron and bilirubin levels, and the risk for myocardial infarction and ischemic stroke. Material and methods Iron, transferrin iron saturation, TIBC, ferritin and bilirubin were analyzed and HFE C282Y, HFE H63D and UGT1A1*28 were determined in myocardial infarction and stroke cases, and their double matched referents within the Northern Sweden Health and Disease Study Cohort. Results There were no associations between iron levels in the upper normal range and risk for myocardial infarction or stroke. No associations were seen for HFE-genotypes, except for a near fivefold increase in risk for myocardial infarction in HFE H63D homozygous women. Plasma bilirubin was lower in cases vs. referents both in the myocardial infarction and the stroke cohort. Despite a strong gene-dosage effect on bilirubin levels in both cases and referents, the UGT1A1*28 polymorphism did not influence the risk for myocardial infarction or stroke. Conclusion High iron stores are not associated with increased risk for neither myocardial infarction, nor stroke. There was no association between UGT1A1*28 and the risk for myocardial infarction or stroke. Consequently data suggests that other factors, which also may lower bilirubin, are responsible for the elevated risk observed in conjunction with lower bilirubin levels.

Inherited disorders of bilirubin metabolism - hereditary hyperbilirubinemias - are metabolic disorders manifested in early childhood. Unconjugated hyperbilirubinemias result from the defect of the enzyme uridine diphosphoglucuronosyltransferase (UGT1A1). UGT1A1 mediates the conjugation of bilirubin with glucuronid acid in hepatocytes and its elimination to water soluble compound. In the next step of bilirubin degradation the transport of conjugated bilirubin from hepatocyte into the bile occure. It is caused by the ATP dependent transporters ABCC2, ATP1B1 and OATP1B3. Mutations in the genes coding the bilirubin transporters results in conjugated hyperbilirubinemia Dubin-Johnson or Rotor syndrome. This study is focused on unconjugated hyperbilirubinemia in adolescents including the non-typical manifestations and the defects of ABCC2 transporter and their phenotype in humans.

La puissance de la biopile enzymatique à glucose/oxygène est limitée par sa partiecathodique. Afin de contourner cette limitation, nous avons étudié les enzymescathodiques : les Bilirubine oxydases (BODs). Dans le but de mieux appréhender ces BODs, lemécanisme réactionnel, la nature de l’étape limitante et l’effet des sels ont alors été étudiés.Deux mécanismes différents sont retrouvés en fonction du mode de transfert des protons etdes électrons (4 fois 1H+/1e- ou 2 fois 2H+/2e-). De plus, nous avons démontré que l’étapelimitante est l’oxydation du substrat pour les trois substrats testés et que les sels agissent auniveau du cuivre T1. Les principales limitations des BODs sont leur stabilité à 37 °C ainsi queleur inhibition par le NaCl. Deux techniques ont alors été utilisées pour identifier des BODsplus résistantes. La première méthode est l’extraction de nouvelles enzymes à partird’organismes extremophiles. Elle a permis d’isoler la BOD d’Anaerophaga thermohalophilaqui possède une bonne résistance au NaCl mais une densité de courant faible. Dans unsecond temps, afin de reconstruire des séquences ancestrales, la phylogénie de la familledes Bacillus Bacterium a été effectuée. Cette technique a permis l’identification de troisBODs possédant des caractéristiques très intéressantes : la BOD de Bacillus nakamurai etdeux BODs ancestrales (Noeud 10 et Noeud 13). Par exemple, après une heure à 37°C et 140mM de NaCl, le Noeud 10 possède une meilleure densité de courant que la BOD de Bacilluspumilus, qui est l’enzyme utilisée comme base de la phylogénie. La seconde technique estdonc une méthode de choix permettant la découverte de nouvelles enzymes à la fois plusstables et plus résistantes que les enzymes actuelles. Elle ouvre de grandes perspectivespour l’utilisation des BODs comme enzymes cathodiques ou pour d’autres applicationsbiotechnologiques. Enfin, nous avons montré que l’immobilisation de la BOD de B. pumilusdans le matériau Si-(HIPE) permet la décoloration cyclique de colorants chimiques surplusieurs mois. / Power of glucose/oxygen enzymatic biofuel cell is limited by the cathodic part. In order to prevent this limitation, we studied cathodic enzymes: Bilirubin oxidases (BODs). For this purpose, the kinetic mechanism, rate-limiting step and salts effect were determined. Two different mechanisms are observed depending on the electron/proton transfer (4 times1H+/1e- or 2 times 2H+/2e-). We also demonstrated that the rate-limiting step is the substrate oxidation for the three substrates tested and salts act around the T1 copper. Main BODs limitations are their stability at 37°C and their inhibition by NaCl. Two methods were used toidentify the most resistant BODs. The first one was the identification of new enzymes from extremophile organisms. It allows to isolate BOD from Anaerophaga thermohalophila whichhas good NaCl resistance but low current density. In addition, in order to reconstructancestral sequences, phylogeny of Bacillus Bacterium family was performed. This methodidentified three BODs with interesting features: BOD from Bacillus nakamurai and twoancestral BODs (Noeud 10 and Noeud 13). For example, after one hour at 37°C and 140 mMNaCl, Noeud 10 has a better current density than the BOD from Bacillus pumilus, which is theenzyme used as basis for the phylogeny. This second method allowed the discovery of newenzymes that were both more stable and more resistant than actual enzymes. Thistechnique opens up valuable prospects for the use of BODs as cathodic enzymes or for otherbiotechnological applications. In the end, we demonstrated that BOD from B. pumilusimmobilization in Si-(HIPE) materials allows cyclic discoloration of chemical dyes duringseveral months.

INTRODUÇÃO: nos recém-nascidos, diversos componentes das defesas antioxidantes têm se mostrado deficientes. A bilirrubina possui potente ação antioxidante podendo compensar a deficiência dos demais componentes. Essa ação é potencializada pela biliverdina redutase. Esse estudo teve como objetivo identificar o efeito protetor da bilirrubina sobre a sepse neonatal em recém nascidos prematuros. MÉTODOS: estudo de coorte realizado em duas UTI neonatais. Participaram recém-nascidos com idade gestacional inferior a 36 semanas e peso de nascimento entre 750 e 1750 g. As determinações da bilirrubina e da carbonil proteína fizeram-se: a) ao nascimento b) com três dias c) com sete dias e d) com 14 dias de vida. Utilizou-se o teste t de Student nas comparações entre médias. Com as medidas de bilirrubina com três dias foi construída curva ROC. O ponto de inflexão dessa curva separou um grupo exposto a níveis altos de outro (controle) com níveis baixos de bilirrubina. Determinou-se Risco Relativo e intervalo de confiança de 95%. Para variáveis categóricas, utilizou-se o teste do Qui quadrado. A significância estatística foi &#945;=5%. RESULTADOS: o estudo incluiu 53 pacientes. Sepse foi confirmada por hemocultura em 24 pacientes (45,3%). Foram 12 (22,6%) os pacientes com sepse clínica perfazendo 36 (67,9%) pacientes com todas formas de sepse. Sepse grave foi diagnosticada em 21 pacientes (39,6%). Nas comparações entre os valores de bilirrubina nos pacientes que apresentaram cada uma das três formas de sepse e nos pacientes sem sepse houve diferença significante na maioria das situações. Não houve diferença significante nas medidas ao nascimento em todas as formas de sepse e nas medidas aos 14 dias para os pacientes com sepse grave. Ótimos resultados estatísticos ocorreram nas comparações com três dias de vida entre pacientes com sepse comprovada e pacientes sem sepse com p= 0,0009. O ponto de inflexão da curva ROC, com bilirrubina em 9,8mg% separou os pacientes em grupo exposto e não exposto. Comparação quanto à presença ou não de sepse entre os grupos mostrou diferença estatisticamente significante, considerando-se cada uma das formas de sepse analisadas. Para sepse confirmada encontrou-se RR=0,39 (IC95% 0,22- 0,71) e p=0,0008. Nas curvas padrão para bilirrubina, houve diferença significante entre as áreas das duas curvas, com os pacientes sem sepse apresentando área maior. A correlação entre os valores máximos de bilirrubina e os valores máximos da carbonil proteína foi inversa e estatisticamente significante (p=0,016). A diferença entre os valores da carbonil proteína nos pacientes com cada uma das formas de sepse analisadas e os dos pacientes sem sepse, não atingiu significância estatística. O conjunto dos resultados do estudo mostra uma relação estatisticamente significante entre níveis mais elevados de bilirrubina e menor incidência e gravidade da sepse neonatal e uma correlação significante entre bilirrubina e carbonil proteína. CONCLUSÃO: maiores níveis séricos de bilirrubina protegem os prematuros da ocorrência e gravidade da sepse devido as suas propriedades antioxidantes. / INTRODUCTION: several components of the antioxidative defenses are deficient in the newborn. Bilirubin is a potent antioxidant and can counterbalance the deficiency of those components. This antioxidant action is potencialized by biliverdin reductase. The present study aimed at identifying the protective effect of bilirubin on neonatal sepsis in premature babies. METHODS: cohort study, carried out in two neonatal intensive care unities. Newborns younger than 36 gestational age weeks and birth weight between 750 and 1750g were included in the study. Bilirubin and protein carbonyl measurements were performed: a) at birth, b) at day three, c) at day seven, d) at day fourteen. Student t test was used for mean comparisons. Bilirubin measurements at day three were used to build a ROC curve. The inflection point of this curve separated the high bilirubin from the low bilirubin group. Relative risk and 95% confidence interval were determined. Chi-square test was applied for categorical variables and the significance level was set at &#945;=5%. RESULTS: fifty-three patients were included in the study. Twenty-four patients (45.3%) had proven sepsis, twelve (22.6%) had clinical sepsis, totaling 36 (67.9%) patients with all forms of sepsis and 21 (39.6%) patients with severe sepsis. Comparisons between bilirubin values in patients with each form of sepsis and patients without sepsis showed significant differences in most of the situations. There was no statistically significant difference in birth measures in all forms of sepsis as well as in day 14 measurements for severe sepsis. Very good statistical results were found on day three comparisons between proven sepsis and no sepsis patients p=0.0009. The ROC curve inflection point, with bilirubin level at 9.8 mg%, identified an exposed and a non-exposed group. Comparisons regarding the presence of sepsis between groups showed a statistically significant difference, considering each of the analyzed sepsis forms. For proven sepsis RR=0.39 (95%CI 0.22-0.71) p=0.0008. Bilirubin curves showed a significant difference between the areas of the two curves, with patients without sepsis displaying a larger area. The correlation between bilirubin maximum values and protein carbonyl maximum values was inverse and significant (p=0.016). The difference regarding protein carbonyl values between patients with each form of sepsis and patients without sepsis did not reach statistical significance. These results show a statistical significant relation between higher bilirubin levels and a lower incidence and severity of neonatal sepsis and a significant correlation between bilirubin and protein carbonyl. CONCLUSION: higher bilirubin levels protect premature babies from the occurrence and severity of sepsis due to its antioxidative properties.

Biocélulas a combustível (BFCs) são definidas como dispositivos bioeletroquímicos que utilizam componentes biológicos, como enzimas ou microrganismos, para converter energia química em energia elétrica. Neste estudo, reporta-se o desenvolvimento de um bioeletrodo composto por fibras flexíveis de carbono (FFC) modificadas com a enzima álcool desidrogenase (ADH), o qual foi utilizado juntamente com a levedura Saccharomyces cerevisiae , sendo enzima e microrganismos usados como biocatalisadores cooperativos para bioprodução e oxidação de etanol. A glicose é oxidada pelas células de levedura sob condições anaeróbias, e o etanol formado pela fermentação alcóolica é, em seguida, oxidado a acetaldeído pela enzima ADH. A oxidação de etanol pela ADH resulta ainda, na redução da molécula de nicotinamida adenina dinucleotídeo, NAD+ a NADH. Posteriormente, o NADH formado nessa reação é eletroquimicamente oxidado a NAD+ na superfície do bioeletrodo de FFC baseado em ADH (FFC-ADH). Avaliou-se a influência da temperatura e do pH na bioeletrocatálise de etanol pela ADH e a melhor resposta obtida foi em 40 ºC e pH 8,5. Além disso, obteve-se uma excelente correlação linear entre os valores de concentração de etanol e densidade de corrente, indicando que a resposta bioeletrocatalítica da ADH é diretamente proporcional à concentração de etanol produzido a partir da fermentação. O conceito de que microrganismos e enzimas podem trabalhar cooperativamente para produzir uma nova classe de bioeletrodos, foi introduzido nesse trabalho. Por fim, demonstrou-se, que o bioeletrodo cooperativo pode ser aplicado com sucesso em uma BFC, utilizando o biocátodo de difusão de gás contendo a enzima bilirrubina oxidase (BOx) imobilizada em sua superfície. / Biofuel cells (BFCs) are defined as bioelectrochemical devices that use biological components, such as enzymes or microorganisms, to convert chemical energy into electric energy. In this study, we report the development of a bioelectrode composed of flexible carbon fibers (FCF) modified with the enzyme alcohol dehydrogenase (ADH) together with Saccharomyces cerevisiae yeast, being enzyme and microorganisms used as cooperative biocatalysts for bioproduction and oxidation of ethanol. Glucose is oxidized by the yeast cells in anaerobic conditions, and ethanol is produced through alcoholic fermentation and then it is oxidized to acetaldehyde by the ADH enzyme. The ethanol oxidation by ADH also results in the reduction of the nicotinamide adenine dinucleotide molecule, NAD+ to NADH. Subsequently, the NADH produced in this reaction is electrochemically oxidized to NAD+ on the surface of the FCF bioelectrode based on ADH (FCF-ADH). The influence of temperature and pH on the bioelectrocatalysis of ethanol was evaluated and the best performance was found at 40 ºC and pH 8.5. Additionally, the results demonstrated an excellent linear correlation between the ethanol concentration and the current generated, which indicates that the bioelectrocatalytic response of ADH is directly proportional to concentration of ethanol produced from the fermentation. The present study has introduced the concept that microorganisms and enzymes can work cooperatively to produce a new class of bioelectrodes. Finally, it has been demonstrated that the cooperative bioelectrode can be applied successfully to BFC using a gas-diffusion biocathode containing the bilirubin oxidase enzyme (BOx) immobilized on its surface.

INTRODUÇÃO: nos recém-nascidos, diversos componentes das defesas antioxidantes têm se mostrado deficientes. A bilirrubina possui potente ação antioxidante podendo compensar a deficiência dos demais componentes. Essa ação é potencializada pela biliverdina redutase. Esse estudo teve como objetivo identificar o efeito protetor da bilirrubina sobre a sepse neonatal em recém nascidos prematuros. MÉTODOS: estudo de coorte realizado em duas UTI neonatais. Participaram recém-nascidos com idade gestacional inferior a 36 semanas e peso de nascimento entre 750 e 1750 g. As determinações da bilirrubina e da carbonil proteína fizeram-se: a) ao nascimento b) com três dias c) com sete dias e d) com 14 dias de vida. Utilizou-se o teste t de Student nas comparações entre médias. Com as medidas de bilirrubina com três dias foi construída curva ROC. O ponto de inflexão dessa curva separou um grupo exposto a níveis altos de outro (controle) com níveis baixos de bilirrubina. Determinou-se Risco Relativo e intervalo de confiança de 95%. Para variáveis categóricas, utilizou-se o teste do Qui quadrado. A significância estatística foi &#945;=5%. RESULTADOS: o estudo incluiu 53 pacientes. Sepse foi confirmada por hemocultura em 24 pacientes (45,3%). Foram 12 (22,6%) os pacientes com sepse clínica perfazendo 36 (67,9%) pacientes com todas formas de sepse. Sepse grave foi diagnosticada em 21 pacientes (39,6%). Nas comparações entre os valores de bilirrubina nos pacientes que apresentaram cada uma das três formas de sepse e nos pacientes sem sepse houve diferença significante na maioria das situações. Não houve diferença significante nas medidas ao nascimento em todas as formas de sepse e nas medidas aos 14 dias para os pacientes com sepse grave. Ótimos resultados estatísticos ocorreram nas comparações com três dias de vida entre pacientes com sepse comprovada e pacientes sem sepse com p= 0,0009. O ponto de inflexão da curva ROC, com bilirrubina em 9,8mg% separou os pacientes em grupo exposto e não exposto. Comparação quanto à presença ou não de sepse entre os grupos mostrou diferença estatisticamente significante, considerando-se cada uma das formas de sepse analisadas. Para sepse confirmada encontrou-se RR=0,39 (IC95% 0,22- 0,71) e p=0,0008. Nas curvas padrão para bilirrubina, houve diferença significante entre as áreas das duas curvas, com os pacientes sem sepse apresentando área maior. A correlação entre os valores máximos de bilirrubina e os valores máximos da carbonil proteína foi inversa e estatisticamente significante (p=0,016). A diferença entre os valores da carbonil proteína nos pacientes com cada uma das formas de sepse analisadas e os dos pacientes sem sepse, não atingiu significância estatística. O conjunto dos resultados do estudo mostra uma relação estatisticamente significante entre níveis mais elevados de bilirrubina e menor incidência e gravidade da sepse neonatal e uma correlação significante entre bilirrubina e carbonil proteína. CONCLUSÃO: maiores níveis séricos de bilirrubina protegem os prematuros da ocorrência e gravidade da sepse devido as suas propriedades antioxidantes. / INTRODUCTION: several components of the antioxidative defenses are deficient in the newborn. Bilirubin is a potent antioxidant and can counterbalance the deficiency of those components. This antioxidant action is potencialized by biliverdin reductase. The present study aimed at identifying the protective effect of bilirubin on neonatal sepsis in premature babies. METHODS: cohort study, carried out in two neonatal intensive care unities. Newborns younger than 36 gestational age weeks and birth weight between 750 and 1750g were included in the study. Bilirubin and protein carbonyl measurements were performed: a) at birth, b) at day three, c) at day seven, d) at day fourteen. Student t test was used for mean comparisons. Bilirubin measurements at day three were used to build a ROC curve. The inflection point of this curve separated the high bilirubin from the low bilirubin group. Relative risk and 95% confidence interval were determined. Chi-square test was applied for categorical variables and the significance level was set at &#945;=5%. RESULTS: fifty-three patients were included in the study. Twenty-four patients (45.3%) had proven sepsis, twelve (22.6%) had clinical sepsis, totaling 36 (67.9%) patients with all forms of sepsis and 21 (39.6%) patients with severe sepsis. Comparisons between bilirubin values in patients with each form of sepsis and patients without sepsis showed significant differences in most of the situations. There was no statistically significant difference in birth measures in all forms of sepsis as well as in day 14 measurements for severe sepsis. Very good statistical results were found on day three comparisons between proven sepsis and no sepsis patients p=0.0009. The ROC curve inflection point, with bilirubin level at 9.8 mg%, identified an exposed and a non-exposed group. Comparisons regarding the presence of sepsis between groups showed a statistically significant difference, considering each of the analyzed sepsis forms. For proven sepsis RR=0.39 (95%CI 0.22-0.71) p=0.0008. Bilirubin curves showed a significant difference between the areas of the two curves, with patients without sepsis displaying a larger area. The correlation between bilirubin maximum values and protein carbonyl maximum values was inverse and significant (p=0.016). The difference regarding protein carbonyl values between patients with each form of sepsis and patients without sepsis did not reach statistical significance. These results show a statistical significant relation between higher bilirubin levels and a lower incidence and severity of neonatal sepsis and a significant correlation between bilirubin and protein carbonyl. CONCLUSION: higher bilirubin levels protect premature babies from the occurrence and severity of sepsis due to its antioxidative properties.

Dans la nature, la réduction du dioxygène est catalysée par des enzymes de la famille des oxydoréductases. A l’heure actuelle, ces protéines spécifiques et efficaces sont envisagés comme biocatalyseurs au sein de biopile enzymatique. Dans ce contexte, l’optimisation de l’orientation et de la connexion d’oxydases multi-cuivre (MCOs) pour la réduction d’O2 sur des matrices de nanotubes carbone (CNTs) fonctionnalisées a été étudiée. Dans un premier temps, le transfert électronique direct de la laccase est optimisé par la fonctionnalisation non covalente de CNTs par divers dérivés hydrophobes. La dynamique moléculaire ainsi que la modélisation électrochimique ont permis la rationalisation des performances des différentes biocathodes développées. Dans une seconde approche, la modification spécifique par des groupements pyrène de la surface de laccases modifiées par mutagénèse a également été envisagée. La fonctionnalisation supramoléculaire de CNTs par des feuillets de graphène fonctionnalisés d’une part, et par des nanoparticules d’or d’autre part, a également permis de favoriser la connexion de laccases. La seconde partie présente l’élaboration d’autres types de biocathodes basées sur la connexion directe de bilirubines oxydases. Plusieurs stratégies de fonctionnalisation covalente et non covalente de CNTs ont été envisagées. Les différentes biocathodes élaborées par l’assemblage supramoléculaire de MCOs et de matériaux nanostructurés délivrent des densités de courant de réduction du dioxygène de plusieurs mA cm-2. Ces nouvelles bioélectrodes combinées à une bioanode qui catalyse l’oxydation du glucose ont permis le développement de biopiles enzymatiques glucose/O2 délivrant des densités maximales de puissances allant de 250 µW cm-2 à 750 µW cm-2 selon les conditions expérimentales. Enfin une bioanode à base d’une hydrogénase hyperthermophile a été développée et associée à une biocathode à base de bilirubine oxydase pour former un nouveau design de biopile H2/O2. Au sein de ce dispositif, la biocathode à diffusion de gaz réduit directement l’oxygène provenant de l’air, ce qui permet de s’affranchir de l’utilisation d’une membrane séparatrice tout en protégeant l’hydrogénase de sa désactivation en présence d’oxygène. Cette nouvelle biopile délivre une densité maximale de puissance de 750 µW cm-2. / The reduction of oxygen is realized in nature by oxidoreductase enzymes. Currently, these highly specific and efficient proteins are considered as biocatalysts for the development of biofuel cells. In this context, optimizing the orientation and the connection of multicopper oxidase (MCOs) for the reduction of O2 on functionalized carbon nanotubes was studied. In the first part of this manuscript, direct electron transfer of laccase is assessed and optimized by the non-covalent functionalization of CNTs by various hydrophobic derivatives. Electrochemical modeling and molecular dynamics enabled the rationalization of the developed biocathodes efficiency. In a second approach, the specific modification by pyrene moieties of laccases surface modified by protein engineered has also been considered. Additionally, supramolecular functionalization of CNTs by modified graphene sheets and gold nanoparticles also helped to promote laccase connection. The second part presents the development of other types of biocathodes based on the direct connection of bilirubin oxidase. Several strategies of covalent and non-covalent CNTs functionalization have been considered. The different biocathodes developed by the supramolecular assembly of nanostructured materials and MCOs delivered current density of several mA cm-2 for oxygen reduction. These new bioelectrodes combined with a bioanode which catalyzes the glucose oxidation have enabled the development of glucose/O2 enzymatic biofuel cells; delivering maximum power densities from 250 µW cm-2 to 750 µW cm-2 depending on the experimental conditions. Finally a hyperthermophilic hydrogenase based bioanode was developed and associated with a bilirubin oxidase-based biocathode to form a new design of H2/O2 biofuel cell. Within this device, the gas diffusion biocathode directly reduces oxygen from the air, which eliminates the use of a separation membrane while protecting the hydrogenase from its deactivation in the presence oxygen. This new biofuel cell delivers a maximum power density of 750 µW cm-2.