The Metabolomic Signature of the Placenta in Spontaneous Preterm Birth

The placenta is metabolically active and supports the growth of the fetus. We hypothesize that deficits in the capacity of the placenta to maintain bioenergetic and metabolic stability during pregnancy may result in spontaneous preterm birth (SPTB). To explore this hypothesis, we performed a nested cased control study of metabolomic signatures in placentas from women with SPTB (<36 weeks gestation) compared to normal pregnancies (≥38 weeks gestation). To control for the effects of gestational age on placenta metabolism, we also studied a subset of metabolites in non-laboring preterm and term Rhesus monkeys. Comprehensive quantification of metabolites demonstrated a significant elevation in the levels of amino acids, prostaglandins, sphingolipids, lysolipids, and acylcarnitines in SPTB placenta compared to term placenta. Additional quantification of placental acylcarnitines by tandem mass spectrometry confirmed the significant elevation in SPTB human, with no significant differences between midgestation and term placenta in Rhesus macaque. Fatty acid oxidation as measured by the flux of ³H-palmitate in SPTB placenta was lower than term. Collectively, significant and biologically relevant alterations in the placenta metabolome were identified in SPTB placenta. Altered acylcarnitine levels and fatty acid oxidation suggest that disruption in normal substrate metabolism is associated with SPTB.

Treatment of congenital pulmonary lymphangiectasia using ethiodized oil lymphangiography

Historically, congenital pulmonary lymphangiectasia (CPL) has had poor treatment outcomes despite aggressive therapy. There are recent reports of ethiodized oil (Lipiodol) lymphangiography successfully treating lymphatic leakage in adults. In this report, we describe two infants with CPL complicated by chylothoraces successfully treated by instillation of ethiodized oil into the lymphatic system. Congenital atresia of the thoracic duct was demonstrated on the lymphangiogram in both patients before treatment. Both patients have shown good short-term outcomes without supplemental oxygen or fat restricted diets at 9 months of age. Ethiodized oil lymphangiography represents a new treatment modality for some patients with CPL.

A spectrum of phenotypical expression OF Neu-Laxova syndrome: Three case reports and a review of the literature

Neu-Laxova syndrome is a rare autosomal recessive disorder characterized by severe intra-uterine growth restriction, extreme microcephaly, marked edema with skin restriction, ichthyosis, craniofacial anomalies, limb deformities, and a spectrum of central nervous system malformations. Less than 70 cases have been described since the first report in 1971. To this day the etiology and genetic basis remains unknown. Consanguinity has been reported. Some authors have postulated the syndrome to be a form of neuro-ectodermal dysplasia, while others suggest that it is a malformation syndrome secondary to severe skin restriction. Although the outcome of this syndrome is lethal, a single case of longer survival (6 months) has been reported. The majority of cases are stillborn or die shortly after birth. Thus, it is clear that Neu-Laxova exhibits a spectrum of disease, with varying degrees of phenotypic expression. We are presenting three new cases of Neu-Laxova syndrome; two were stillbirths and one lived for eleven weeks. Our microscopic and post-mortem findings in these three cases display the vast spectrum of this rare syndrome.

Targeted transgenic overexpression of mitochondrial thymidine kinase (TK2) alters mitochondrial DNA (mtDNA) and mitochondrial polypeptide abundance: transgenic TK2, mtDNA, and antiretrovirals

Mitochondrial toxicity limits nucleoside reverse transcriptase inhibitors (NRTIs) for acquired immune deficiency syndrome. NRTI triphosphates, the active moieties, inhibit human immunodeficiency virus reverse transcriptase and eukaryotic mitochondrial DNA polymerase pol-gamma. NRTI phosphorylation seems to correlate with mitochondrial toxicity, but experimental evidence is lacking. Transgenic mice (TGs) with cardiac overexpression of thymidine kinase isoforms (mitochondrial TK2 and cytoplasmic TK1) were used to study NRTI mitochondrial toxicity. Echocardiography and nuclear magnetic resonance imaging defined cardiac performance and structure. TK gene copy and enzyme activity, mitochondrial (mt) DNA and polypeptide abundance, succinate dehydrogenase and cytochrome oxidase histochemistry, and electron microscopy correlated with transgenesis, mitochondrial structure, and biogenesis. Antiretroviral combinations simulated therapy. Untreated hTK1 or TK2 TGs exhibited normal left ventricle mass. In TK2 TGs, cardiac TK2 gene copy doubled, activity increased 300-fold, and mtDNA abundance doubled. Abundance of the 17-kd subunit of complex I, succinate dehydrogenase histochemical activity, and cristae density increased. NRTIs increased left ventricle mass 20% in TK2 TGs. TK activity increased 3 logs in hTK1 TGs, but no cardiac phenotype resulted. NRTIs abrogated functional effects of transgenically increased TK2 activity but had no effect on TK2 mtDNA abundance. Thus, NRTI mitochondrial phosphorylation by TK2 is integral to clinical NRTI mitochondrial toxicity.

Health care utilization and expenditures for children with autism: data from U.S. national samples

Little is known about the use of medical services by children who have autism (ASD). Provide nationally representative data for health service utilization and expenditures of children with ASD. Cross-sectional survey using the Medical Expenditure Panel (MEPS), and National (Hospital) Ambulatory Medical Care Surveys (N(H)AMCS). A total of 80 children with ASD were identified from N(H)AMCS (weighted sample size (wss) 186,281), and 31 (wss 340,158) from MEPS. They had more outpatient visits, physician visits, and medications prescribed than children in general. They spent more time during physician visits than other children. Annual expenses for children with autism spectrum disorder (6,132 dollars) were more than for other children (860 dollars). Children with ASD have a substantial burden of medical illness.

Antiretroviral nucleosides, deoxynucleotide carrier and mitochondrial DNA: evidence supporting the DNA pol gamma hypothesis

DESIGN

Nucleoside reverse transcriptase inhibitors (NRTIs) exhibit mitochondrial toxicity. The mitochondrial deoxynucleotide carrier (DNC) transports nucleotide precursors (or phosphorylated NRTIs) into mitochondria for mitochondrial (mt)DNA replication or inhibition of mtDNA replication by NRTIs. Transgenic mice (TG) expressing human DNC targeted to murine myocardium served to define mitochondrial events from NRTIs in vivo and findings were corroborated by biochemical events in vitro.

METHODS

Zidovudine (3'-azido-2',3'-deoxythymidine; ZDV), stavudine (2', 3'-didehydro-2', 3'-deoxythymidine; d4T), or lamivudine ((-)-2'-deoxy-3'-thiacytidine; 3TC) were administered individually to TGs and wild-type (WT) littermates (35 days) at human doses with drug-free vehicle as control. Left ventricle (LV) mass was defined echocardiographically, mitochondrial ultrastructural defects were identified by electron microscopy, the abundance of cardiac mtDNA was quantified by real time polymerase chain reaction, and mtDNA-encoded polypeptides were quantified.

RESULTS

Untreated TGs exhibited normal LV mass with minor mitochondrial damage. NRTI monotherapy (either d4T or ZDV) increased LV mass in TGs and caused significant mitochondrial destruction. Cardiac mtDNA was depleted in ZDV and d4T-treated TG hearts and mtDNA-encoded polypeptides decreased. Changes were absent in 3TC-treated cohorts. In supportive structural observations from molecular modeling, ZDV demonstrated close contacts with K947 and Y951 in the DNA pol gamma active site that were absent in the HIV reverse transcriptase active site.

CONCLUSIONS

NRTIs deplete mtDNA and polypeptides, cause mitochondrial structural and functional defects in vivo, follow inhibition kinetics with DNA pol gamma in vitro, and are corroborated by molecular models. Disrupted pools of nucleotide precursors and inhibition of DNA pol gamma by specific NRTIs are mechanistically important in mitochondrial toxicity.

Transgenic expression of the deoxynucleotide carrier causes mitochondrial damage that is enhanced by NRTIs for AIDS

Nucleoside reverse transcriptase inhibitors (NRTIs) are antiretrovirals for AIDS with limiting mitochondrial side effects. The mitochondrial deoxynucleotide carrier (DNC) transports phosphorylated nucleosides for mitochondrial DNA replication and can transport phosphorylated NRTIs into mitochondria. Transgenic mice (TG) that exclusively overexpress DNC in the heart tested DNC's role in mitochondrial dysfunction from NRTIs. Two TG lines were created that overexpressed the human DNC gene in murine myocardium. Cardiac and mitochondrial structure and function were examined by magnetic resonance imaging, echocardiography, electrocardiography, transmission electron microscopy, and plasma lactate. Antiretroviral combinations (HAART) that contained NRTIs (stavudine (2', 3'-didehydro-2', 3'-deoxythymidine or d4T)/lamivudine/indinavir; or zidovudine (3' azido-3'-deoxythymidine or AZT)/lamivudine/indinavir; 35 days) were administered to simulate AIDS therapy. In parallel, a HAART combination without NRTIs (nevirapine/efavirenz/indinavir; 35 days) served as an NRTI-sparing, control regimen. Untreated DNC TGs exhibited normal cardiac function but abnormal mitochondrial ultrastructure. HAART that contained NRTIs caused cardiomyopathy in TGs with increased left ventricle mass and volume, heart rate variability, and worse mitochondrial ultrastructural defects. In contrast, treatment with an NRTI-sparing HAART regimen caused no cardiac changes. Data suggest the DNC is integral to mitochondrial homeostasis in vivo and may relate mechanistically to mitochondrial dysfunction in patients treated with HAART regimens that contain NRTIs.

HLA-A and HLA-B in Kenya, Africa: allele frequencies and identification of HLA-B*1567 and HLA-B*4426

HLA-A and HLA-B alleles of a population from Kenya, Africa were examined by sequencing exon 2 and exon 3 DNA and typing using a Taxonomy-based Sequence-analysis (TBSA) method. Extensive diversities were observed at both HLA-A and HLA-B loci in this population. Forty-one HLA-A alleles were identified from 159 unrelated individuals. The most frequently observed alleles were A*6802 (11.64%), A*02011/09 (9.75%), A*7401/02 (9.43%), A*3001 (7.86%), A*3002 (7.23%) and A*3601 (6.6%). Forty-nine HLA-B alleles were identified in 161 unrelated individuals, including two novel alleles, B*1567 and B*4426. The most frequently observed HLA-B alleles were B*5301 (9.01%), B*5801 (8.38%), B*4201 (7.76%), B*1503 (7.14%), B*1801 (6.21%), and B*5802 (5.90%). The most frequently observed HLA-A-B haplotypes were A*3601-B*5301 (3.55%) and A*3001-B*4201 (3.19%), followed by A*7401/02-B*5801 (2.84%), A*7401/02-B*5802 (2.84%) and A*02011/09-B*1503 (2.13%). Linkage disequilibrium and chi2 analysis showed the association of these HLA-A-B haplotypes at the antigen level to be significant. The frequencies of HLA-A and HLA-B alleles from the Kenyan population were compared with that of a population from Cameroon. The difference in allele and haplotype frequency distributions partly reflected the different ethnic composition of these two African populations.

Suppression of gonadotropin secretion by a long-acting gonadotropin-releasing hormone analog (leuprolide acetate, Lupron Depot) in children with precocious puberty

The GnRH analog leuprolide acetate has been shown to be effective in the treatment of precocious puberty when given as a daily sc injection. We studied the effectiveness of a single im dose of a new depot form of leuprolide in suppressing estradiol and gonadotropin secretion in children with precocity. Five girls with previously untreated precocity showed significant decreases in basal serum estradiol and FSH levels and in peak LH levels (after GnRH testing) 30 days after a single im dose of leuprolide acetate for depot suspension. Mean peak FSH levels also fell greatly, but the difference was not significant. No adverse effects were noted during the first 4-6 months of monthly im injections. Depot im leuprolide appears to be effective in suppressing estradiol and gonadotropin secretion, and may be a useful method of treating children with central precocious puberty.

Efficacy of leuprolide therapy in children with central precocious puberty

Eight girls with central precocious puberty were treated with the long-acting gonadotropin releasing hormone analogue leuprolide acetate (Lupron) for a period of six to 18 months. Suppression of gonadotropin and estradiol secretion and regression of secondary sexual characteristics and menses were observed while patients received a subcutaneous dose of 35 to 40 micrograms/kg/d. Growth velocity was slowed in all but one patient, and the rate of skeletal maturation was slowed even more, resulting in a stabilization or improvement in predicted adult height. There were no major side effects. Although the long-term effects of leuprolide therapy cannot be determined with this study, it appears to be efficacious in the treatment of central precocious puberty.