Environmental Exposure to Dioxins, Dibenzofurans, Bisphenol A, and Phthalates in Children with and without Autism Spectrum Disorder Living near the Gulf of Mexico.

Environmental exposure to organic endocrine disrupting chemicals, including dioxins, dibenzofurans, bisphenol A (BPA), and phthalates has been associated with neurodevelopmental disorders, including autism spectrum disorder (ASD). We conducted a pilot monitoring study of 30 ASD cases and 10 typically developing (TD) controls ages 2-8 years from communities along the Gulf of Mexico near Alabama, which houses 14 Superfund sites, to assess the concentrations of dioxins and dibenzofurans in serum, and BPA and phthalate ester metabolites in urine. Based on General Linear Models, the lipid- or creatinine-adjusted geometric mean concentrations of the aforementioned chemicals did not differ between the ASD case and TD control groups (all p ≥ 0.27). We compared our findings to the adjusted means as reported by the National Health and Nutrition Examination Survey, survey years 2011-2012, and found that TD controls in our study had lower BPA (59%) and MEHHP (26%) concentrations, higher MBP (50%) concentration, and comparable (<20% difference) MEP, MBZP, MEOHP, and MCPP concentrations. We also conducted a preliminary investigation of dietary exposures and found that the consumption of certain types of fish may be associated with higher OCDD concentrations, and the consumption of soft drinks and juices may be associated with lower BPA and MEOHP concentrations, respectively.

Craniofacial dysmorphism and developmental disorders among children with chromosomal microdeletions and duplications of unknown significance.

OBJECTIVE: Microarray comparative genomic hybridization is an extremely sensitive technology that increasingly identifies deletions and duplications of unknown significance. Our objective was to determine whether children with autism and other developmental delays who have genomic imbalances manifest more craniofacial dysmorphism and have lower cognitive scores than children from the same clinic population who have normal microarrays. METHOD: A clinical geneticist, blinded to the history, reviewed photographs for craniofacial dysmorphism. Forty-five (24%) of 187 children who had a microarray had a deletion or duplication >200 kb. Thirty-six of those with abnormal microarrays (11 microdeletions and 25 duplications) had completed their evaluation, which included 3 deletions and 10 duplications of unknown significance. Subjects with and without microarray anomalies did not differ in age, sex, growth parameters, parental age or education level, insurance status, or cognitive scores. RESULTS: Twenty-eight (78%) of the 36 children with microarray anomalies had craniofacial dysmorphism as compared with 45% of those with normal microarrays (p = .0005). Among the 13 children with microarray abnormalities of unknown significance, 10 (77%) were dysmorphic, similar to 18 (78%) of 23 who had a genomic imbalance known to affect development. Among the 10 children with dysmorphism and a microarray anomaly of unknown significance, 7 also had an IQ ≤70 and/or a diagnosis of autism. CONCLUSION: Microdeletions and duplications not previously known to be associated with human disease were strongly associated with craniofacial dysmorphism, cognitive scores ≤70, and a diagnosis of autism in this clinic population, providing presumptive evidence that these genomic imbalances are clinically significant.

Abortion and the risk of subsequent preterm birth: a systematic review with meta-analyses.

OBJECTIVE: To conduct a systematic review and meta-analyses of studies that test the association between induced or spontaneous abortion and subsequent preterm birth. STUDY DESIGN: International databases were reviewed (1995-2007) using the terms preterm, premature, birth, labor, delivery, abortion, induced abortion, miscarriage and spontaneous abortion. Only studies that met prespecified objective criteria for methodologic design and reporting were included in the meta-analyses. RESULTS: Twelve induced and 9 spontaneous abortion studies met inclusion criteria. Common adjusted odds ratios (ORs) for preterm birth following 1 and > or = 2 induced abortions were 1.25 (95% confidence interval [95% CI] 1.03-1.48) and 1.51 (95% CI 1.21-1.75), respectively. Four studies provided a common adjusted OR for < or = 32 weeks' births of 1.64 (95% CI 1.38-1.91). Meta-regression analysis revealed a previously unrecognized inverse relationship between the In OR and the control population preterm birth rate, explaining in part the observed heterogeneity among studies. Analysis of spontaneous abortion and subsequent preterm birth revealed a similar common adjusted OR and inverse meta-regression on the control preterm birth rates. CONCLUSION: Induced and spontaneous abortion are associated with similarly increased ORs for preterm birth in subsequent pregnancies, and they vary inversely with the baseline preterm birth rate, explaining some of the variability among studies.

Deleting Ku70 is milder than deleting Ku80 in p53-mutant mice and cells.

Ku70 forms a heterodimer with Ku80, called Ku that is well known for repairing DNA double-strand breaks through non-homologous end joining. As a result, deletion of either causes a very similar phenotype in mice that includes hypersensitivity to clastogens and early aging. In addition, deletion of Ku80 along with the cell cycle checkpoint protein, p53, dramatically increases the incidence of pro-B-cell lymphoma. Even though Ku70- p53-mutant mice have not been analysed, a logical assumption is they would exhibit the same cancer phenotype. Here, we test this assumption by comparing p53-mutant littermates deleted for either Ku70 or Ku80 or both. We find this assumption to be incorrect as p53-mutants live significantly longer when deleted for Ku70 rather than Ku80 or Ku70+Ku80. We also find the former cohort displays much lower levels of pro-B-cell lymphoma than the latter two cohorts. As pro-B-cell lymphoma is caused by a translocation between chromosomes 12 and 15, we tested fibroblasts for DNA repair capacity, and found that p53-mutant fibroblasts are more sensitive to streptonigrin and paraquat when deleted for Ku80 as compared with Ku70. Thus, Ku80 may function outside the Ku heterodimer to influence DNA damage repair presenting the possibility that Ku80 influenced the open coding ends in a manner that suppressed a cancer-causing translocation.

Signs of myocardial ischaemia after injection of oxytocin: a randomized double-blind comparison of oxytocin and methylergometrine during Caesarean section.

BACKGROUND: ECG changes, similar to those seen during myocardial ischaemia, together with symptoms of chest pain, are common during Caesarean section (CS). We hypothesized that oxytocin administration has cardiovascular effects leading to these symptoms and ECG changes. METHODS: Forty women undergoing elective CS under spinal anaesthesia were given an i.v. bolus of either 10 IU of oxytocin (Group OXY-CS, n=20) or 0.2 mg of methylergometrine (Group MET-CS, n=20), in a double-blind, randomized fashion after delivery. Ten healthy, non-pregnant, non-anaesthetized women were used as normal controls (Group OXY-NC, n=10) and were given 10 IU of oxytocin i.v. Twelve-lead ECG, on-line, computerized vectorcardiography (VCG), and invasive arterial pressure were recorded. RESULTS: Oxytocin produced a significant increase in heart rate, +28 (SD 4) and +52 (3) beats min(-1) [mean (SEM); P<0.001], decreases in mean arterial pressure, -33 (2) and -30 (3) mm Hg (P<0.001), and increases in the spatial ST-change vector magnitude (STC-VM), +77 (12) and +114 (8) microV (P<0.001), in CS patients and controls, respectively. Symptoms of chest pain and subjective discomfort were simultaneously present. Methylergometrine produced mild hypertension and no significant ECG changes. CONCLUSIONS: Oxytocin administered as an i.v. bolus of 10 IU induces chest pain, transient profound tachycardia, hypotension, and concomitant signs of myocardial ischaemia according to marked ECG and STC-VM changes. The effects are related to oxytocin administration and not to pregnancy, surgical procedure, delivery, or sympathetic block from spinal anaesthesia.

Barriers to children having a medical home in Johnson County, Iowa: notes from the field.

BACKGROUND: In Iowa 70.7% of children who qualify for Title XIX and/or Title V services have a medical home, but in Johnson County, Iowa only 54.0% of such children have one. Objectives Identify barriers to access to a medical home for children who use Johnson County Public Health (JCPH) services and recommend strategies to overcome these barriers. METHODS: Families with children attending JCPH well-child and WIC clinics were randomly selected to be interviewed using a semi-structured, 38-item questionnaire. Data analysis used qualitative and quantitative methodologies. RESULTS: Among 71 families interviewed, 41 had children without a medical home and 85% of these families cited financial barriers. Lack of U.S. citizenship accounted for 59% without health insurance. A recent move contributed to 29% not having medical homes. Nine different languages were spoken among the 41 families without a medical home. Forty-one percent of all parents interviewed had never had a medical home themselves. Many parents perceived emergency departments as more convenient than doctors' offices. CONCLUSIONS: Lack of health insurance, due primarily to citizenship status, is the greatest barrier to access to a medical home in this population. The migratory nature of the U.S. population, marked cultural diversity, and parental attitudes were additional barriers to children's access to a medical home. Strategies to overcome these barriers are discussed.

Long-term neurodevelopmental outcome and brain volume after treatment for hydrops fetalis by in utero intravascular transfusion.

OBJECTIVE: We tested the hypothesis that long-term neurodevelopmental outcomes of successfully treated fetuses with immune hydrops are similar to their unaffected siblings according to a protocol that addresses the underlying pathophysiologic condition. STUDY DESIGN: Sixteen of 18 consecutive hydropic fetuses (89%) who were treated in a dedicated fetal medicine unit between July 1985 and October 1995 survived. The transfusion protocol used a 2-step correction over a 2 to 4 day interval, combined with umbilical venous pressure measurements to avoid over transfusion and bicarbonate administration to assure a posttransfusion UV pH of >7.30. Survivors were evaluated at a mean age of 10 years. Statistical analyses included t-test, Wilcoxon rank-sum test, Fisher's exact test, and Pearson coefficients. RESULTS: Overall, death or major neurologic morbidity occurred in 4 of 18 of the fetuses (22%) who were treated (2/16 of survivors [12.5%]). Among the survivors, the children with immune hydrops had physical, neurologic, and cognitive outcomes statistically similar to their siblings, except for a measure of visual attention. Two of the children (12%) had major neurologic sequelae. Brain volumes were statistically smaller than unrelated control subjects by 8.8%, but these control subjects were not matched for height at testing or gestational age at birth. Both groups had brain volumes within the normal range. CONCLUSION: Intravascular transfusion of fetuses with profoundly anemic immune hydrops results in high survival rates and favorable long-term neuropsychological outcomes.

Behavioral management of a long-term survivor with tetrasomy 18p.

We report on a 41-year-old male with dysmorphic features, marked obesity, profound mental retardation, and aggressive behavior who was recently diagnosed with tetrasomy of the short arm of chromosome 18, [47, XY, i(18)(p10)]. His initial diagnosis, based upon chromosomal analysis at 6 years of age in 1969, was "trisomy F syndrome." Approximately 60 cases of tetrasomy 18p are reported in the literature, with little information regarding their long-term behavioral profiles or outcomes from therapy. We describe the behavioral management as well as the medical and genetic evaluation for this older patient with tetrasomy. With improved preventive care and intervention, patients with rare chromosomal abnormalities are living longer and, therefore, provide insight into the natural history of their disorders. Efforts need to be directed toward behavior management, social skills training, and augmentation of communication if the quality of life of these individuals is to continue to improve.

A comparative analysis of bone and cartilage metabolism in two strains of guinea-pig with varying degrees of naturally occurring osteoarthritis.

OBJECTIVE: To evaluate the interaction of bone and cartilage in knee osteoarthritis (OA) pathogenesis in two guinea-pig strains with appreciable differences in bone metabolism. DESIGN: Two guinea-pig strains were evaluated for their susceptibilities to OA using semi-quantitative histological grading of knee joints and quantification of biomarkers including urinary excretion of hydroxylysyl-pyridinoline (HP) and lysyl-pyridinoline (LP) collagen cross-links, serum osteocalcin (OC), and synovial fluid levels of keratan sulfate (KS). RESULTS: At 12 months of age, Strain 13 guinea-pigs had minimal to mild histological evidence of OA compared to the Hartley strain guinea-pigs. The Hartley strain, with more severe OA, had a higher rate of bone formation (serum osteocalcin) and bone resorption (HP and LP) evident at a young age with persistence of a greater rate of bone formation at 12 months of age. The Strain 13 possessed much thicker subchondral bone at the outset (2 months) compared to the Hartley; however, the Hartley strain showed the greatest increase in subchondral bone thickness coincident with the development of cartilage degeneration. Thus, the process of subchondral bone thickening, in contrast to the absolute initial subchondral bone thickness, was a hallmark of OA in the guinea-pig. Moreover, Strain 13 had lower intraarticular proteoglycan turnover. Levels of synovial fluid keratan sulfate were positively correlated with the severity of histological OA. CONCLUSIONS: This pilot study represents the first evidence of differential susceptibility to OA in guinea-pigs. Comparison of these two strains of guinea-pig has revealed that increased metabolism within the affected tissues, cartilage and bone, is associated with the development and progression of OA. This work demonstrates that the Strain 13 is a viable age-matched control to the Hartley strain and merits a more in depth evaluation of the contribution of bone and bone metabolism to OA.

Spontaneous hepatocellular carcinoma is reduced in transgenic mice overexpressing human O6- methylguanine-DNA methyltransferase.

O(6)-methylguanine (O(6)mG) is a potent mutagenic and procarcinogenic DNA lesion. Organisms have evolved with a DNA repair mechanism that largely ameliorates the deleterious effects of O(6)mG through a direct reversal mechanism by a protein termed O(6)-methylguanine-DNA methyltransferase (MGMT). However, the contribution of O(6)mG to carcinogenesis, in the absence of known exposure to agents that produce it, has not been defined. Nontransgenic C3HeB male mice have a high frequency of spontaneous liver tumors. Transgenic CeHeB/FeJ mice expressing human MGMT (hMGMT) were generated that had elevated hepatic MGMT activity. The spontaneous development of hepatocellular carcinoma was significantly reduced in those mice expressing hMGMT compared with nontransgenic C3HeB/FeJ male mice. No differences were detected in spontaneous mutant frequencies in lacI transgenes in mice carrying hMGMT compared with that without hMGMT but the proportion of GC to AT transition mutations was lower in the transgenic mice carrying hMGMT as well as lacI. Tumors that arose in C3HeB/FeJ transgenic mice were largely deficient in hMGMT protein as determined by immunohistochemistry with a monoclonal antibody directed against hMGMT. Together these data indicate that spontaneous O(6)mG lesions induced hepatocellular carcinogenesis in C3HeB/FeJ male mice. These transgenic mice represent a rare example of reduced spontaneous carcinogenesis.

Health span and life span in transgenic mice with modulated DNA repair.

One way to better understand the contribution of DNA repair, DNA damage, and mutagenesis in aging would be to enhance DNA repair activity, lower DNA damage, and lower mutagenesis. Because the repair protein O6-methylguanine-DNA methyltransferase (MGMT) acts alone and stoichiometrically, the human MGMT (hMGMT) cDNA was selected to test the feasibility of enhancing DNA repair activity in transgenic mice. MGMT activity is largely responsible for ameliorating the deleterious effects of O6-methylguanine (O6mG) lesions in DNA in a direct reversal mechanism. A transgene was constructed consisting of a portion of the human transferrin (TF) promoter and hMGMT cDNA such that hMGMT is expressed in transgenic mouse brain and liver. Expression of hMGMT was associated with a significant reduction in the occurrence of an age-related hepatocellular carcinoma in male mice at 15 months of age. Longitudinal and cross-sectional studies were initiated to determine whether the reduced incidence of hepatocellular carcinoma would impact median or maximum life span. The cross-sectional study performed on 15-month-old male animals confirmed the reduced occurrence of spontaneous hepatocellular carcinoma. At 30 months of age, however, the occurrence of hepatocellular carcinoma in at least one transgenic line was similar to that for nontransgenic animals. The longitudinal study is ongoing; however, at present no significant differences in life span have been detected. Tissues expressing the MGMT transgene also displayed greater resistance to alkylation-induced tumor formation. These results suggest that transgenes can be used to direct enhanced DNA repair gene expression and that enhanced expression can protect animals from certain spontaneous and induced tumors.

High physiological levels of melatonin in the bile of mammals.

Bile is an important physiological bodily fluid which functions in the regulation of cholesterol metabolism, promotes the absorption of lipid and fat-soluble vitamins by the gut and serves in the excretion of toxic substances from the liver. Conversely, due to autooxidative processes bile is highly toxic to the hepatocyte and gastrointestinal epithelium. In this investigation, extremely high day time physiological levels of the endogenous antioxidant, melatonin, were measured in the bile of several mammals including rat, guinea pig, rabbit, pig, monkey and humans. Melatonin concentrations in the bile samples ranged from 2,000 to 11,000 pg/ml when measured by radioimmunoassay (RIA). These melatonin levels in bile are 2 to 3 orders of magnitude higher than those in day time serum. The presence of melatonin in bile was confirmed by HPLC with an electrochemical detector. This method, like the RIA, also documented very high levels of melatonin in bile. The presence of high levels of melatonin in bile may be essential to prevent oxidative damage to biliary and small intestinal epithelium induced by bile acids and oxidized cholesterol derivatives.

Microbial pathogenesis in cystic fibrosis: pulmonary clearance of mucoid Pseudomonas aeruginosa and inflammation in a mouse model of repeated respiratory challenge.

Chronic endobronchiolitis compounded by recurring Pseudomonas aeruginosa infections is the major cause of morbidity and mortality in patients with cystic fibrosis (CF). In this study, a mouse model of repeated respiratory exposure to P. aeruginosa was established to facilitate investigations of factors contributing to P. aeruginosa persistence and associated inflammatory processes in the lung. While a single exposure to P. aeruginosa aerosols resulted in only mild histopathological changes, repeated exposure caused significant lung pathology in C57BL/6J mice. The peak of histopathological changes and inflammation in C57BL/6J mice was characterized by subacute lymphohistiocytic bronchopneumonia and persistent elevation of tumor necrosis factor alpha and macrophage inflammatory protein 2 in the lung but not in the serum. When isogenic nonmucoid (mucA+) and mucoid (mucA22) P. aeruginosa strains were compared, the mucoid cells were cleared several-fold less efficiently than the parental nonmucoid strain during the initial stages of the aerosol exposure regimen. However, the microscopic pathology findings and proinflammatory cytokine levels were similar in mice exposed to nonmucoid and mucoid P. aeruginosa throughout the infection. We also tested lung histopathology and proinflammatory cytokines in interleukin 10 (IL-10)-deficient transgenic (IL-10T) mice. Significant mortality was seen in IL-10T mice on initial challenge with P. aeruginosa, although no histopathological differences could be observed in the lungs of C57BL/6J and surviving IL-10T mice after a single exposure. However, increased pathology was detected in IL-10T mice relative to C57BL/6J after repeated challenge with P. aeruginosa. This observation supports the proposals that anti-inflammatory cytokines may play a role in suppressing P. aeruginosa-induced tissue damage during chronic infection.

Cadmium toxicity and distribution in metallothionein-I and -II deficient transgenic mice.

To date, numerous correlative studies have implicated metallothionein in the detoxification of heavy metals and in the regulation of metal distribution within an organism. In the present study cadmium-binding proteins (metallothionein equivalents), cadmium acute toxicity, and cadmium distribution in tissues and subcellular fractions were compared in metallothionein-I and -II deficient (MT-/-) mice and the parental strain carrying intact metallothionein genes (MT+/+) to determine if the absence of metallothionein altered any of these parameters. In an uninduced state, MT-/- mice expressed lower levels of cadmium-binding proteins relative to MT+/+ mice in several tissues. Administration of zinc enhanced the levels of cadmium-binding proteins in liver, small intestine, kidney, pancreas, and male sex organs, but not in cecum or brain of MT+/+ mice compared to zinc pretreated MT-/- mice. The cadmium LD50 was similar for MT-/-, MT+/+, and zinc-pretreated MT-/- mice (15-17 mumol CdCl2/kg body weight delivered i.p.). However, zinc-pretreated MT+/+ mice had a cadmium LD50 of 58-63 mumol CdCl2/kg body weight. Over two-thirds of cadmium was found in liver, cecum, small intestine, and kidney in both MT+/+ and MT-/- mice; therefore, metallothionein levels do not appear to play a major role in the tissue distribution of cadmium. However, after zinc pretreatment, MT+/+ mice accumulated more cadmium in the liver and less in other tissues, whereas the amount of cadmium in the liver was not altered by zinc pretreatment in MT-/- mice. In general, the cytosolic/particulate ratio of cadmium was significantly higher in tissues of noninduced MT+/+ mice relative to MT-/- mice. This difference was accentuated after zinc pretreatment. Together these results indicate that basal levels of metallothionein do not protect from the acute toxicity of a single i.p. cadmium challenge. Furthermore, it does not appear that the cytosolic compartmentalization of cadmium is correlated with reduced toxicity.

Experimental infection of cynomolgus macaques with Ebola-Reston filoviruses from the 1989-1990 U.S. epizootic.

This study describes the pathogenesis of the Ebola-Reston (EBO-R) subtype of Ebola virus for experimentally infected cynomolgus monkeys. The disease course of EBO-R in macaques was very similar to human disease and to experimental diseases in macaques following EBO-Zaire and EBO-Sudan infections. Cynomolgus monkeys infected with EBO-R in this experiment developed anorexia, occasional nasal discharge, and splenomegaly, petechial facial hemorrhages and severe subcutaneous hemorrhages in venipuncture sites, similar to human Ebola fever. Five of the six EBO-R infected monkeys died, 8 to 14 days after inoculation. One survived and developed high titered neutralizing antibodies specific for EBO-R. The five acutely ill monkeys shed infectious virus in various bodily secretions. Further, abundant virus was visualized in alveolar interstitial cells and free in the alveoli suggesting the potential for generating infectious aerosols. Thus, taking precautions against aerosol exposures to filovirus infected primates, including humans, seems prudent. This experiment demonstrated that EBO-R was lethal for macaques and was capable of initiating and sustaining the monkey epizootic. Further investigation of this animal model should facilitate development of effective immunization, treatment, and control strategies for Ebola hemorrhagic fever.

Fibrosarcomas in two rats arising from hepatic cysts of Cysticercus fasciolaris.

Two of five male Sprague-Dawley rats with hepatic tapeworm cysts developed large multinodular fibrosarcomas. Fibrosarcomas envelope tapeworm cysts, invaded the serosa of multiple organs, and extended through the diaphragm into the pleural cavity. Light microscopy, immunohistochemistry, and electron microscopy supported the diagnosis of fibrosarcoma. The parasites were identified as Cysticercus fasciolaris, the larval stage of Taenia taeniaeformis. The development of sarcomas in rats induced by Taenia sp. is thought to be attributable to the chronic inflammatory reaction of the capsule. There are parallels between these and other tumors occurring in mice and cats with suggested chronic inflammatory etiologies.