Antenatal causes of cerebral palsy: associations between inherited thrombophilias, viral and bacterial infection, and inherited susceptibility to infection

Bioinformatics-based discovery of biomarkers and immunoinflammatory targets in children with cerebral palsy: An observational study

Cerebral palsy (CP) is the most common disabling disease in children, and motor dysfunction is the core symptom of CP. Although relevant risk factors have been found to be closely associated with CP: congenital malformations, multiple gestation, prematurity, intrauterine inflammation and infection, birth asphyxia, thrombophilia, and perinatal stroke. Its important pathophysiological mechanism is amniotic fluid infection and intraamniotic inflammation leading to fetal developing brain damage, which may last for many years. However, the molecular mechanism of CP is still not well explained. This study aimed to use bioinformatics to identify key biomarker-related signaling pathways in CP. The expression profile of children with CP was selected from the Gene Expression Comprehensive Database, and the CP disease gene data set was obtained from GeneCards. A protein-protein interaction network was established and functional enrichment analysis was performed using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases. A total of 144 differential key intersection genes and 10 hub genes were identified through molecular biology. Gene Ontology functional enrichment analysis results show that differentially expressed genes are mainly concentrated in biological processes, such as immune response and neurogenesis. The cellular components involved mainly include axons, postsynaptic membranes, etc, and their molecular functions mainly involve proteoglycan binding, collagen binding, etc. Kyoto Encyclopedia of Genes and Genomes analysis shows that the intersection genes are mainly in signaling pathways related to the immune system, inflammatory response, and nervous system, such as Th17 cell differentiation, Toll-like receptor signaling pathway, tumor necrosis factor signaling pathway, NF-κB signaling pathway, axon guidance, PI3K-Akt signaling pathway, HIF-1 signaling pathway, gap junction, etc. Jak-STAT signaling pathway, mTOR signaling pathway, and related hub genes regulate immune cells and inflammatory factors and play an important role in the development and progression of CP.

Fetal heart rate monitoring in labor: from pattern recognition to fetal physiology

The journey of human labor involves hypoxic and mechanical stresses as a result of progressively increasing frequency, duration and strength of uterine contractions and resultant compression of the umbilical cord. In addition, occlusion of the spiral arteries during myometrial contractions also leads to repetitive interruptions in the utero-placental circulation, predisposing a fetus to progressively worsening hypoxic stress as labor progresses. The vast majority of fetuses are equipped with compensatory mechanisms to withstand these hypoxic and mechanical stresses. They emerge unharmed at birth. However, some fetuses may sustain an antenatal injury or experience a chronic utero-placental insufficiency prior to the onset of labor. These may impair the fetus to compensate for the ongoing hypoxic stress secondary to ongoing uterine contractions. Non-hypoxic pathways of neurological damage such as chorioamnionitis, fetal anemia or an acute fetal hypovolemia may potentiate fetal neurological injury, especially in the presence of a super-imposed, additional hypoxic stress. The use of utero-tonic agents to induce or augment labor may increase the risk of hypoxic-ischemic injury. Clinicians need to move away from "pattern recognition" guidelines ("normal," "suspicious," "pathological"), and apply the knowledge of fetal physiology to differentiate fetal compensation from decompensation. Individualization of care is essential to optimize outcomes.

TNF-α and MTHFR Polymorphisms Associated with Cerebral Palsy in Chinese Infants

This study aims to examine whether the presence of polymorphisms in TNF-α (rs361525 and rs1799724) and MTHFR (rs1476413 and rs9651118) genes is associated with the pathogenesis of cerebral palsy (CP). A total of 105 CP patients and 114 age-, gender-, and ethnicity-matched healthy controls were genotyped for the selected polymorphisms, using TaqMan allelic discrimination assay. Odds ratios (OR) and 95 % confidence intervals (CI) were determined to measure the strength of associations of TNF-α and MTHFR polymorphisms with CP. The proportion of subjects with the gestational age more than 37 weeks or asphyxia was much larger in cases compared with controls (gestational age 63.8 vs. 34.2 %; asphyxia 25.7 vs. 7.9 %). The genotype frequencies of TNF-α rs1799724 were similar between groups (P > 0.05), yet the allele distributions were significantly different (P < 0.05). Both the allele and genotype distributions of MTHFR rs9651118 polymorphism varied significantly between the groups (P < 0.05). Subgroup analysis based on gestational age indicated a significant association between rs361525 and rs9651118 and CP with or without premature. TNF-α protein concentrations were significantly increased among patients with rs361525 GG genotype compared with controls. Also, a significant increase in the risk of CP was observed to be associated with the interactions of TNF-α rs1799724 and MTHFR rs9651118 (OR 2.75, 95 % CI 1.23-6.13). These data suggest that polymorphisms in TNF-α and MTHFR genes might be involved in the pathogenesis of CP in Chinese infants.

Chorioamnionitis and cerebral palsy: lessons from a patient registry

AIM

The fetal neuroinflammatory response has been linked to the development of brain injury in newborns and subsequent neurologic impairment. We aimed to explore the maternal and child factors associated with histologic chorioamnionitis in cerebral palsy.

METHODS

We conducted an observational study on a cohort of children with cerebral palsy who were identified from the Quebec Cerebral Palsy Registry. Placental pathology was reported prospectively. Maternal and child factors associated with histological chorioamnionitis were explored.

RESULTS

Placental reports were available in 455 of 534 (85%) children with cerebral palsy, and of these 12% had histological signs of chorioamnionitis on reports. These children were more likely to have large placentas over 90th percentile for gestational age (53.7% versus 30.7%, p = 0.001) and were born significantly more prematurely (<32 weeks in 51.9% vs 24.1%, p = 0.007) than children without chorioamnionitis. A clinical sign of perinatal infection was reported in 61.1% of children with chorioamnionitis, however each clinical sign was seen in a minority of these children. Children with chorioamnionitis were more likely to have spastic diplegic cerebral palsy subtype (37% vs 19.2%, p = 0.003) and periventricular white matter injury on neuroimaging (52.9% vs 35.8%, p = 0.004). However no differences in neuroimaging or subtypes were seen when stratified by prematurity.

DISCUSSION

Histological chorioamnionitis was a frequent pathological finding in children with cerebral palsy born prematurely, with larger placentas relative to gestation and birth weight. Future case control studies are needed to shed light on the role of inflammatory placental findings in pregnancy outcomes.

Pathophysiology of cerebral palsy

Cerebral palsy (CP), defined as a group of nonprogressive disorders of movement and posture, is the most common cause of severe neurodisability in children. Understanding its physiopathology is crucial to developing some protective strategies. Interruption of oxygen supply to the fetus or brain asphyxia was classically considered to be the main causal factor explaining later CP. However several ante-, peri-, and postnatal factors could be involved in the origins of CP syndromes. Congenital malformations are rarely identified. CP is most often the result of environmental factors, which might interact with genetic vulnerabilities, and could be severe enough to cause the destructive injuries visible with standard imaging (i.e., ultrasonographic study or MRI), predominantly in the white matter in preterm infants and in the gray matter and the brainstem nuclei in full-term newborns. Moreover they act on an immature brain and could alter the remarkable series of developmental events. Biochemical key factors originating in cell death or cell process loss, observed in hypoxic-ischemic as well as inflammatory conditions, are excessive production of proinflammatory cytokines, oxidative stress, maternal growth factor deprivation, extracellular matrix modifications, and excessive release of glutamate, triggering the excitotoxic cascade. Only two strategies have succeeded in decreasing CP in 2-year-old children: hypothermia in full-term newborns with moderate neonatal encephalopathy and administration of magnesium sulfate to mothers in preterm labor.

Postpartum care of a woman with cerebral palsy and deep vein thrombosis: a case study

Pregnancy can be challenging for women with cerebral palsy. Physical limitations and comorbidities can predispose them to complications during pregnancy, such as deep vein thrombosis and pulmonary embolism, making their care needs more complex. A multidisciplinary care plan, as well as clear and effective communication among different health care providers, will help ensure safe and optimal postpartum care of women with cerebral palsy and their newborns.

Candidate genes and risk for CP: a population-based study

Studies suggest that genetic polymorphisms may increase an individual's susceptibility to CP. Most findings have yet to be corroborated in an independent cohort. This case-control study is nested within all 334,333 infants ≥36 wk gestation born at Kaiser Permanente Medical Care Program, 1991-2002. We included only non-Hispanic whites who had a neonatal blood sample available. Case patients (n = 138) were identified from medical records to have spastic or dyskinetic CP. Controls (n = 165) were randomly selected from the population. We genotyped polymorphisms previously associated with CP: inducible NOS (iNOS)-231, apolipoprotein E (apoE) ε2 and ε4 alleles, TNF-α-308, IL-8 -251, lymphotoxin 60, endothelial NOS -922, endothelial protein C receptor 219, mannose-binding lectin 54 and 52, factor V Leiden, methyltetrahydrofolate reductase 1298 and 667, prothrombin 20210, and platelet activator inhibitor 11053. Similar to previous reports, the iNOS-231 T allele (25.7 versus 18.9%, p = 0.04) and the apoE ε4 allele (19.3 versus 13.2%, p = 0.04) were more common in patients with CP than in controls. However, there was no statistically significant association between any genetic polymorphism and CP after correction for multiple comparisons.

[Chorio-amnionitis: clinical and biological aspects--medicolegal implications]

The authors present fetal and maternal risks in chorio-amnionitis diseases. Major fetal risk is the increase of the rate of cerebral palsy which is growing to five. The protocol of 2011 is presented for the prevention and treatment of chorio-amnionitis in premature rupture of the membranes in relation with gestational age. A French statistical survey, period 2001 to 2006, indicates maternal risks of chorio-amnionitis. Medicolegal implications of the chorio-amnionitis diseases emphasize the importance of placental investigations and bacteriological tests.

Chronic fetal hypoxia produces selective brain injury associated with altered nitric oxide synthases

OBJECTIVE

The purpose of this study was to investigate the impact of chronic hypoxia on the nitric oxide synthase isoenzymes in specific brain structures.

STUDY DESIGN

Time-mated pregnant guinea pigs were exposed to 10.5% molecular oxygen for 14 days (animals with chronic fetal hypoxia; HPX) or room air (control animals; NMX); L-N6-(1-iminoethyl)-lysine (L-NIL; an inducible nitric oxide synthase inhibitor, 1 mg/kg/d) was administered to HPX group for 14 days (L-NIL + HPX). Fetal brains were harvested at term. Multilabeled immunofluorescence was used to generate a brain injury map. Laser capture microdissection and quantitative polymerase chain reaction were applied; cell injury markers, apoptosis activation, neuron loss, total nitric oxide, and the levels of individual nitric oxide synthase isoenzymes were quantified.

RESULTS

Chronic hypoxia causes selective fetal brain injury rather than global. Injury is associated with differentially affected nitric oxide synthases in both neurons and glial cells, with inducible macrophage-type nitric oxide synthase up-regulated at all injury sites. L-NIL attenuated the injury, despite continued hypoxia.

CONCLUSION

These studies demonstrate that chronic hypoxia selectively injures the fetal brain in part by the differential regulation of nitric oxide synthase isoenzymes in an anatomic- and cell-specific manner.

Familial recurrence of cerebral palsy with multiple risk factors

The recurrence of cerebral palsy in the same family is uncommon. We, however, report on two families with two or more affected siblings. In both families, numerous potential risk factors were identified including environmental, obstetric, and possible maternal effects. We hypothesize that multiple risk factors may lead to the increased risk of recurrence of cerebral palsy in families. Intrinsic and maternal risk factors should be investigated in all cases of cerebral palsy to properly counsel families on the risk of recurrence. Recent studies of genetic polymorphisms associated with cerebral palsy are considered with reference to our observations in these two families.

Cerebral palsy in eastern Denmark: declining birth prevalence but increasing numbers of unilateral cerebral palsy in birth year period 1986-1998

The Cerebral Palsy Registry in eastern Denmark has been collecting cases using a uniform data sampling procedure since birth year 1979. Children are included by two child neurologists and an obstetrician. Information on pregnancy, birth, neonatal period, impairments and demographic data are registered. The total cerebral palsy birth prevalence has been significantly decreasing since the birth period 1983-1986 with 3.0 per 1000 live births until the period 1995-1998 with 2.1 per 1000 live births. The overall decrease was seen in preterm infants (<31 weeks) as well as in term infants and despite a simultaneous fall in perinatal and early neonatal mortality in the preterm group. Analysing the subtypes of CP we found a significant increase in the numbers as well as the rate of unilateral CP with a simultaneous fall in the numbers as well as the rate of bilateral CP. The explanation of this rise is not obvious. A change from bilateral periventricular lesions to unilateral is a possibility, but no major change in the neonatal handling could be documented. Regarding associated impairments, developmental delay/learning disabilities as well as motor function assessed by ability to walk (unassisted/assisted), both have changed toward higher percentage of children with unassisted walking and in need of special education.

Brain injury caused by chronic fetal hypoxemia is mediated by inflammatory cascade activation

The prevalence of cerebral palsy (CP) shows little temporal or geographic variation and is associated with preterm birth, maternal/fetal infection/inflammation, and fetal growth restriction (IUGR), a potential surrogate for chronic fetal hypoxemia (CHX). We previously demonstrated CHX causes a fetal inflammatory response syndrome (FIRS). Herein, we test the hypothesis that CHX may cause fetal brain injury by upregulating inflammatory cytokine cascades, culminating in apoptosis pathway activation. Time-mated guinea pigs were housed in 12% or 10.5% O(2) for the last 21% of gestation. Chronic fetal hypoxemia increased the lactate/pyruvate and decreased the glutathione (GSH)/oxidized glutathione (GSSH) ratios, confirming a shift to a prooxidant state. The end result was a >30% decrease in hippocampal neuron density. Based on a microarray spotted with 113 cytokines and receptors, 22 genes were upregulated by CHX in proportion to the degree of hypoxia; the findings were confirmed by quantitative polymerase chain reaction (PCR). Thus, CHX triggers fetal brain inflammation inversely proportional to its severity characterized by increased apoptosis and neuronal loss. We suggest CHX fetal brain injury is not directly caused by oxygen deprivation but rather is an adaptive response that becomes maladaptive.

Integrated review of cytokines in maternal, cord, and newborn blood: part II-- associations with early infection and increased risk of neurologic damage in preterm infants

A growing body of literature supports the relationship of maternal inflammation with preterm birth and adverse neonatal outcomes, including infection and central nervous system (CNS) dysfunction. Mediators of inflammation, most notably proinflammatory cytokines, have been implicated as having an association with and perhaps playing a causal role in the pathogenesis, leading to adverse neonatal outcomes. Even though the association of cytokines with early adverse neonatal outcomes has been actively pursued as a line of research, there has been little integration of diverse findings across studies. Therefore, the purpose of this systematic review was to appraise and classify empirical evidence from human studies for the association of cytokine levels in blood (serum, plasma, or cells; maternal, cord, or neonatal) with two adverse early outcomes in preterm infants: early infection and increased risk of neurologic damage. The review revealed that the proinflammatory cytokines most frequently linked with sepsis are in the interleukin (IL) 1 family as well as tumor necrosis factor alpha (TNF-alpha) and IL-6. The proinflammatory cytokines most frequently linked to neurologic insult in the reviewed studies were IL-1beta, IL-6, and IL-8. In all cases where IL-1beta was studied, the levels were increased when there was neurologic insult. A better understanding of the relationship of these inflammatory substances with these adverse conditions is needed for the future development of maternal and neonatal biobehavioral nursing research.

Methodologic issues in the study of the relationship between histologic indicators of intraamniotic infection and clinical outcomes

GOAL

To determine the structure of the relationships of the histology scores for acute intraamniotic infection collected in the Collaborative Perinatal Project (CPP).

MATERIALS AND METHODS

44,427 subjects of the CPP had complete histology scores available for the 9 measures that related to acute intraamniotic infection (i.e., neutrophil infiltrates in umbilical cord, amnion of extraplacental membranes and chorionic plate, decidua, chorionic plate and fetal chorionic vessels). Confirmatory factor analysis was used to determine the relationships among the different markers of maternal inflammatory responses (in amnion, chorion and decidua) and fetal inflammatory responses (in umbilical cord and fetal chorionic vessels).

RESULTS

A single CFA model could not be developed across all CPP sites. A well-fit model was developed from the Boston site (N=10,803) and the factor loadings applied to the histology scores from the other CPP sites. The resultant scores for the latent variables (maternal and fetal inflammatory responses) were compared across sites. There was not only considerable variability in factor loadings, and the signs of factor loadings were also inconsistent across sites.

CONCLUSION

Histopathology scores of neutrophil infiltrates performed by different observers do not have the same interrelationships and, by extension, the latent variables they are supposed to reflect may not be equivalent. The lack of measurement invariance renders their use as indicators of the underlying processes of maternal and fetal inflammatory responses problematic in analysis with any clinical outcome.

Hyperthermia during anaesthesia and intensive care unit stay

Nosocomial hyperthermia (fever) occurs in about 30% of all medical patients at some time during their hospital stay. In patients admitted to the intensive care unit with severe sepsis the incidence of hyperthermia is greater than 90%, while in a specialized neurological critical care unit the incidence is reported as 47%. In contrast, hyperthermia during anaesthesia is rare owing to the impairment of thermoregulation by anaesthetic agents. This article is designed to give an overview on the various causes of hyperthermia with special emphasis on fever during general and regional anaesthesia in general and neurological critical care patients.

Fetal exposure to herpesviruses may be associated with pregnancy-induced hypertensive disorders and preterm birth in a Caucasian population

OBJECTIVE

To investigate the role of fetal viral infection in the development of a range of adverse pregnancy outcomes (APOs), including pregnancy-induced hypertensive disorders (PIHD), antepartum haemorrhage (APH), birthweight <10th percentile (small for gestational age, SGA) and preterm birth (PTB).

DESIGN

Population-based case-control study.

SETTING

Laboratory-based study.

POPULATION

The newborn screening cards of 717 adverse pregnancy cases and 609 controls.

METHODS

Newborn screening cards were tested for RNA from enteroviruses and DNA from herpesviruses using polymerase chain reaction (PCR). The herpesviruses were detected using two PCRs, one detecting nucleic acids from herpes simplex virus (HSV)-1, HSV-2, Epstein-Barr virus (EBV), cytomegalovirus (CMV) and human herpesvirus (HHV)-8, hereafter designated Herpes PCR group A viruses, and the other detecting nucleic acids from varicella-zoster virus (VZV), HHV-6 and HHV-7, hereafter designated Herpes PCR group B viruses.

MAIN OUTCOME MEASURE

Odds ratios and 95% CIs for specific APOs.

RESULTS

For both term and PTBs, the risk of developing PIHD was increased in the presence of DNA from Herpes PCR group B viruses (OR 3.57, 95% CI 1.10-11.70), CMV (OR 3.89, 95% CI 1.67-9.06), any herpesvirus (OR 5.70, 95% CI 1.85-17.57) and any virus (OR 5.17, 95% CI 1.68-15.94). The presence of CMV was associated with PTB (OR 1.61, 95% CI 1.14-2.27). No significant association was observed between SGA or APH and exposure to viral infection.

CONCLUSIONS

Fetal exposure to herpesvirus infection was associated with PIHD for both term and PTBs in this exploratory study. Exposure to CMV may also be associated with PTB. These findings need confirmation in future studies.

Cerebral palsy: introduction and diagnosis (part I)

Cerebral palsy (CP), a static, nonprogressive disorder caused by brain insult or injury in the prenatal, perinatal, and postnatal time period, is the major developmental disability affecting function in children. It is characterized by the inability to normally control motor functions, and it has the potential to have an effect on the overall development of a child by affecting the child's ability to explore, speak, learn, and become independent. Effective management can improve the quality of life for the child and family. The first step for the nurse practitioner is to understand the definition of CP and how to make the diagnosis. This article is part one of two articles on CP. The first article will focus on the diagnosis of CP, and the second will focus on a review of systems approach for management as well as resources for the family and practitioner.

Gestational age at preterm premature rupture of membranes: a risk factor for neonatal white matter damage

OBJECTIVE

Gestational age at delivery and spontaneous prematurity are independent risk factors for white matter damage (WMD). However, among infants delivered spontaneously after preterm premature rupture of membranes (PPROM), latency of PPROM has been inconsistently correlated with risk of WMD. We have explored whether gestational age at membrane rupture is independently associated with WMD.

STUDY DESIGN

Using a cohort of 196 liveborn singleton nonanomalous neonates born at 24.0 to 33.6 weeks from January 1993 to December 2002 after pPROM and who survived 7 days, we compared the characteristics of those who developed WMD (n = 15) with those who did not (n = 181) using Fisher exact test, Student t test, and logistic regression analysis, with a 2-tailed P < .05 or odds ratio (OR) with 95% CI not inclusive of the unity considered significant.

RESULTS

Stepwise logistic regression analysis demonstrated that gestational age at PPROM (P < .001, OR 0.79) was significantly associated with WMD. The association was independent of corticosteroid administration (P = .016), latency interval (P = .69), gestational age at delivery (P = .99), and birth weight (P = .62).

CONCLUSION

Among premature infants born at <34 weeks after pPROM, gestational age at diagnosis is independently associated with WMD.

Can obstetric care provide further improvement in the outcome of preterm infants?

Reducing the incidence of cerebral damage in preterm infants has become a major objective of perinatal medicine. Recent studies have shown that intrapartum hypoxia is implicated in only 10% of cases, whereas prenatal factors are significantly linked with such damage. The main risk factors associated with cerebral palsy are preterm birth, multiple pregnancy, intrauterine infection, serious hypoxaemic and haemodynamic disorders and, possibly, thrombophilic disorders. Recent progress in recognition of the pathogenesis of cerebral white matter damage has underlined the roles of cytokines, including interleukins 1 and 6 and tumour necrosis factor alpha (TNFalpha), and of a massive release of glutamate, which leads to the excitotoxic cascade. Three measures have had demonstrable benefits in improving neonatal outcome in preterm infants: a policy of prenatal transfers to tertiary level care units, antenatal corticosteroid therapy, and administration of antibiotics to women with preterm premature rupture of membranes. The influence of tocolysis is usually considered to be relatively minor, but further studies in very preterm pregnancies may be required. The recent development of tocolytics without major adverse effects will probably facilitate such studies. The mode of delivery of early preterm infants is another important area of controversy. Recent studies have suggested that a policy of elective caesarean section in PPROM and in the case of breech presentation of fetuses weighing less than 1000-1500 g would be beneficial. Lastly, in vitro and animal studies have shown that several pharmacological agents can prevent white matter disease by interacting with cytokine and the excitotoxic cascade. This will probably constitute an important area of research in the future.

Theories of schizophrenia: a genetic-inflammatory-vascular synthesis

BACKGROUND

Schizophrenia, a relatively common psychiatric syndrome, affects virtually all brain functions yet has eluded explanation for more than 100 years. Whether by developmental and/or degenerative processes, abnormalities of neurons and their synaptic connections have been the recent focus of attention. However, our inability to fathom the pathophysiology of schizophrenia forces us to challenge our theoretical models and beliefs. A search for a more satisfying model to explain aspects of schizophrenia uncovers clues pointing to genetically mediated CNS microvascular inflammatory disease.

DISCUSSION

A vascular component to a theory of schizophrenia posits that the physiologic abnormalities leading to illness involve disruption of the exquisitely precise regulation of the delivery of energy and oxygen required for normal brain function. The theory further proposes that abnormalities of CNS metabolism arise because genetically modulated inflammatory reactions damage the microvascular system of the brain in reaction to environmental agents, including infections, hypoxia, and physical trauma. Damage may accumulate with repeated exposure to triggering agents resulting in exacerbation and deterioration, or healing with their removal. There are clear examples of genetic polymorphisms in inflammatory regulators leading to exaggerated inflammatory responses. There is also ample evidence that inflammatory vascular disease of the brain can lead to psychosis, often waxing and waning, and exhibiting a fluctuating course, as seen in schizophrenia. Disturbances of CNS blood flow have repeatedly been observed in people with schizophrenia using old and new technologies. To account for the myriad of behavioral and other curious findings in schizophrenia such as minor physical anomalies, or reported decreased rates of rheumatoid arthritis and highly visible nail fold capillaries, we would have to evoke a process that is systemic such as the vascular and immune/inflammatory systems.

SUMMARY

A vascular-inflammatory theory of schizophrenia brings together environmental and genetic factors in a way that can explain the diversity of symptoms and outcomes observed. If these ideas are confirmed, they would lead in new directions for treatments or preventions by avoiding inducers of inflammation or by way of inflammatory modulating agents, thus preventing exaggerated inflammation and consequent triggering of a psychotic episode in genetically predisposed persons.

Identification of kynurenine pathway enzyme mRNAs and metabolites in human placenta: up-regulation by inflammatory stimuli and with clinical infection

OBJECTIVE

The purpose of this study was to determine whether placental-derived kynurenines (neuroactive metabolites that are derived from tryptophan) contributes to infection-mediated fetal cerebral injury.

STUDY DESIGN

Placentae and cord blood were obtained from term deliveries (n = 16) and preterm deliveries with or without intrauterine bacterial infection (n = 8 per group). We investigated whether the placenta expressed messenger RNAs of kynurenine metabolite-forming enzymes, the effects of infection in vivo on the expression of these enzymes by the placenta, the in vitro effects of bacterial endotoxin lipopolysaccharide on expression and kynurenine metabolite output by the placenta, and the kynurenine metabolite levels in umbilical cord blood.

RESULTS

Placentae expressed messenger RNA of tryptophan-degrading enzymes and synthesized several compounds. The expression of several enzymes increased significantly in placentae that were exposed to infection and/or lipopolysaccharide. Lipopolysaccharide also induced significant increases in placental kynurenine and quinolinic acid output. Kynurenine and quinolinic acid in cord blood of fetuses who were exposed to infection were elevated significantly.

CONCLUSION

Inflammatory mediated release of kynurenines from placentae exposes the fetus to significant amounts of potentially neurotoxic substances.

Genetic thrombophilia

The genetic thrombophilias are an important cause of venous thrombotic events. Much has been learned about the natural history of these disorders, their genetics, and, to a lesser degree, their treatment. This article provides an overview of the genetics of thrombophilia. Specific information on the factor V Leiden mutation;the prothrombin G20210A mutation; and protein C, proteinS, and antithrombin deficiency is reviewed. Current testing and treatment options for the genetic thrombophilias also are discussed.